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Dong Z, Xu Y, Liu S, Li G, Ye M, Ma X, Li S. Water uptake patterns and rooting depths of Tamarix ramosissima in the coppice dunes of the Gurbantünggüt Desert, China: a stable isotope analysis. PLANT BIOLOGY (STUTTGART, GERMANY) 2024. [PMID: 39012225 DOI: 10.1111/plb.13695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 06/24/2024] [Indexed: 07/17/2024]
Abstract
Tamarix ramosissima has an important role in stabilizing sand dunes in desert ecosystems. Understanding the water use strategies of T. ramosissima is essential to understand its adaptations on coppice dunes. We utilized the stable isotopes δ2H and δ18O in soil water, groundwater, and xylem water to identify monthly differences in water sources. Additionally. we explored rooting depth using 2H2O as an artificial tracer. In May, T. ramosissima derived 75% of its water from shallow and middle soil layers. In July, it absorbed 90% water from middle and deep soil layers. In August and September, it acquired approximately 80% of its water from deep soil layers. The labelling using 2H as an artificial tracer indicated that the root system of T. ramosissima could reach depths >500 cm in the coppice dunes. 2H absorption was observed at depths of 100, 200, 300 and 400 cm. Soil water is the dominant water source for T. ramosissima in the coppice dunes because groundwater is at depths >30 m. The flexible water-use strategies of T. ramosissima enable it to effectively utilize different available water sources to adapt to the arid environment. These findings improve our understanding of water uptake patterns and drought adaptation strategies of T. ramosissima in the coppice dunes of desert ecosystems.
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Affiliation(s)
- Z Dong
- College of Life Science, Xinjiang Normal University, Urumqi, China
- Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Urumqi, China
| | - Y Xu
- College of Life Science, Xinjiang Normal University, Urumqi, China
- Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Urumqi, China
| | - S Liu
- College of Life Science, Xinjiang Normal University, Urumqi, China
| | - G Li
- College of Life Science, Xinjiang Normal University, Urumqi, China
- Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Urumqi, China
| | - M Ye
- College of Geographic Science and Tourism, Xinjiang Normal University, Urumqi, China
| | - X Ma
- College of Life Science, Xinjiang Normal University, Urumqi, China
| | - S Li
- Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
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Bachofen C, Tumber-Dávila SJ, Mackay DS, McDowell NG, Carminati A, Klein T, Stocker BD, Mencuccini M, Grossiord C. Tree water uptake patterns across the globe. THE NEW PHYTOLOGIST 2024. [PMID: 38649790 DOI: 10.1111/nph.19762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 03/13/2024] [Indexed: 04/25/2024]
Abstract
Plant water uptake from the soil is a crucial element of the global hydrological cycle and essential for vegetation drought resilience. Yet, knowledge of how the distribution of water uptake depth (WUD) varies across species, climates, and seasons is scarce relative to our knowledge of aboveground plant functions. With a global literature review, we found that average WUD varied more among biomes than plant functional types (i.e. deciduous/evergreen broadleaves and conifers), illustrating the importance of the hydroclimate, especially precipitation seasonality, on WUD. By combining records of rooting depth with WUD, we observed a consistently deeper maximum rooting depth than WUD with the largest differences in arid regions - indicating that deep taproots act as lifelines while not contributing to the majority of water uptake. The most ubiquitous observation across the literature was that woody plants switch water sources to soil layers with the highest water availability within short timescales. Hence, seasonal shifts to deep soil layers occur across the globe when shallow soils are drying out, allowing continued transpiration and hydraulic safety. While there are still significant gaps in our understanding of WUD, the consistency across global ecosystems allows integration of existing knowledge into the next generation of vegetation process models.
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Affiliation(s)
- Christoph Bachofen
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, 1015, Lausanne, Switzerland
- Functional Plant Ecology, Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, 1015, Lausanne, Switzerland
| | - Shersingh Joseph Tumber-Dávila
- Department of Environmental Studies, Dartmouth College, Hanover, NH, 03755, USA
- Harvard Forest, Harvard University, Petersham, MA, 01316, USA
| | - D Scott Mackay
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Nate G McDowell
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
- School of Biological Sciences, Washington State University, Pullman, WA, 99163, USA
| | - Andrea Carminati
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland
| | - Tamir Klein
- Plant & Environmental Sciences Department, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Benjamin D Stocker
- Institute of Geography, University of Bern, Bern, 3013, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, 3013, Bern, Switzerland
| | - Maurizio Mencuccini
- CREAF, Cerdanyola del Vallès, Barcelona, 08193, Spain
- ICREA at CREAF, Cerdanyola del Vallès, Barcelona, 08193, Spain
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, 1015, Lausanne, Switzerland
- Functional Plant Ecology, Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, 1015, Lausanne, Switzerland
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Zhang J, Lin G, Zeng DH. Long-term nitrogen addition modifies fine root growth and vertical distribution by affecting soil nutrient availability in a Mongolian pine plantation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:171168. [PMID: 38401734 DOI: 10.1016/j.scitotenv.2024.171168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
Fine roots are the primary organ of tree species in water and nutrient acquisition, and are the major contributor of forest soil organic carbon (C). However, it remains largely unknown how fine root growth dynamics and vertical distribution respond to long-term nitrogen (N) enrichment, which prevents us from accurately evaluating forest C sequestration potential under N deposition. Here, we investigated the effects of nine-year N addition (0 and 10 g N m-2 year-1) on fine root nutrients, biomass, production, turnover rate and vertical distribution in three soil layers (0-10, 10-20 and 20-40 cm) of a Mongolian pine (Pinus sylvestris var. mongolica) plantation in the Keerqin Sandy Lands, Northeast China. We found that soil inorganic N was increased and Olsen-P was decreased by N addition. N addition increased fine root N, C:P and N:P ratios, but reduced fine root P and C:N ratio across all soil layers. N addition reduced fine root biomass in 0-10 cm soil layer but increased it in 20-40 cm soil layer. N addition accelerated fine root turnover rate in 0-10 cm soil layer, and increased fine root necromass across all soil layers. Moreover, N addition significantly enhanced biomass of ectomycorrhizal extraradical hyphae in the 0-10 cm soil layer. Redundancy analysis showed that variations of fine root traits were well explained by soil NO3--N in 0-10 and 10-20 cm soil layers, and by soil NH4+-N and Olsen-P in 20-40 cm soil layer. Collectively, our results highlight the shift from N limitation to P limitation of Mongolian pine plantations under long-term N addition, and suggest that changes in fine root growth and vertical distribution induced by N addition could accelerate belowground C allocation in Mongolian pine plantations.
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Affiliation(s)
- Jingling Zhang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guigang Lin
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin 150040, China; Northeast Asia Ecosystem Carbon Sink Research Center, School of Forestry, Northeast Forestry University, Harbin 150040, China.
| | - De-Hui Zeng
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; Daqinggou Ecological Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
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Zhang Y, Gu T, He S, Cheng F, Wang J, Ye H, Zhang Y, Su H, Li Q. Extreme drought along the tropic of cancer (Yunnan section) and its impact on vegetation. Sci Rep 2024; 14:7508. [PMID: 38553545 PMCID: PMC10980812 DOI: 10.1038/s41598-024-58068-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/25/2024] [Indexed: 04/02/2024] Open
Abstract
The frequent occurrence of extreme weather events is one of the future prospects of climate change, and how ecosystems respond to extreme drought is crucial for response to climate change. Taking the extreme drought event in the Tropic of Cancer (Yunnan section) during 2009-2010 as a case study, used the standardized precipitation evapotranspiration index to analyse the impact of extreme drought on enhanced vegetation index (EVI), leaf area index (LAI) and gross primary productivity (GPP), and to analyzed the post extreme drought vegetation recovery status. The results indicate the following: (1) Due to the cumulative effects of drought and vegetation phenology, vegetation growth in the months of March to May in 2010 was more severely affected. (2) Compared to EVI and LAI, GPP is more sensitive to drought and can accurately indicate areas where drought has impacted vegetation. (3) Following an extreme drought event, 70% of the vegetation can recover within 3 months, while 2.87-6.57% of the vegetation will remain unrecovered after 6 months. (4) Cropland and grassland show the strongest response, with longer recovery times, while woodland and shrubland exhibit weaker responses and shorter recovery times. This study provides a reference for the effects of extreme drought on vegetation.
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Affiliation(s)
- Yanke Zhang
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China
- Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan Kunming, Kunming, 650500, China
- Center for Geospatial Information Engineering and Technology of Yunnan Province, Kunming, 650500, China
- Wuhan Tianjihang Information Technology Co., Ltd., Wuhan, 430074, China
| | - Tengfei Gu
- Badong National Observation and Research Station of Geohazards, China University of Geosciences (Wuhan), Wuhan, 430074, China
| | - Suling He
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China
- Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan Kunming, Kunming, 650500, China
- Center for Geospatial Information Engineering and Technology of Yunnan Province, Kunming, 650500, China
| | - Feng Cheng
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China
- Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan Kunming, Kunming, 650500, China
- Center for Geospatial Information Engineering and Technology of Yunnan Province, Kunming, 650500, China
| | - Jinliang Wang
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China.
- Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan Kunming, Kunming, 650500, China.
- Center for Geospatial Information Engineering and Technology of Yunnan Province, Kunming, 650500, China.
| | - Hui Ye
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China
- Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan Kunming, Kunming, 650500, China
- Center for Geospatial Information Engineering and Technology of Yunnan Province, Kunming, 650500, China
| | - Yunfeng Zhang
- School of Life Sciences, Yunnan Normal University, Kunming, 650500, China
| | - Huai Su
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China
| | - Qinglei Li
- Faculty of Geography, Yunnan Normal University, Kunming, 650500, China
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He S, Zhang C, Meng FR, Bourque CPA, Huang Z, Li X. Impacts of re-vegetation on soil water dynamics in a semiarid region of Northwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 911:168496. [PMID: 37996020 DOI: 10.1016/j.scitotenv.2023.168496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 11/01/2023] [Accepted: 11/09/2023] [Indexed: 11/25/2023]
Abstract
Understanding how vegetation (shrub) cover in drylands affects local-to-regional soil water dynamics and associated water balances is of immense importance because of the abundance of afforestation projects worldwide. Vegetation's role in the control of soil water presents a particular challenge to soil water storage (SWS) management in the drylands of China. To address this knowledge gap, we conducted a two-year study in the Mu Us Desert of northwest China. The study involved the acquisition of in-situ soil water measurements within the first 180 cm of soil at three sand dune sites characterized by their differences in % shrub cover. The sand dunes varied from a vegetation-free, bare-ground sand dune site (BF) and two partly vegetated sites, one with medium-level (40 %) and another with high shrub cover (80 %; MF and HF, respectively). Results revealed that the site with the high shrub cover (HF) suffered a net reduction in soil water content (SWC) by up to 32.7 and 39.8 % in the shallow and deep subsoil (0-100 and 100-180 cm), respectively, when compared to corresponding changes at the BF site. Soil water content was shown to be largely influenced by site properties, namely shrub biomass and litter density (p < 0.05). Due to aboveground vegetation and rainfall interception by the litter, 32.2 mm of effective rainfall was reduced to the soil for every 10 %-increase in shrub cover. Bands of soil water depletion during the dry year did not fully recover during the following wet year, resulting in the development of a dried soil layer with an average SWC of 4.6-7.8 %. Increased evapotranspiration (ETtotal) led to a decrease in SWS and relative extractable soil water (REW), which caused ETtotal at HF to be lower than the rate observed at MF. These findings highlight the need for improvements in current restoration strategies, meant at striking a balance between vegetation restoration and SWC by developing optimal plant-community cover and mosaicked vegetation systems.
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Affiliation(s)
- Shuai He
- College of Desert Control Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, People's Republic of China
| | - Chengfu Zhang
- College of Desert Control Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, People's Republic of China.
| | - Fan-Rui Meng
- Faculty of Forestry and Environmental Management, University of New Brunswick, 28 Dineen Drive, PO Box 4400, Fredericton, New Brunswick E3B 5A3, Canada
| | - Charles P-A Bourque
- Faculty of Forestry and Environmental Management, University of New Brunswick, 28 Dineen Drive, PO Box 4400, Fredericton, New Brunswick E3B 5A3, Canada
| | - Zhenying Huang
- Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, People's Republic of China
| | - Xiang Li
- College of Desert Control Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, People's Republic of China
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Chen Z, Wang G, Pan Y, Shen Y, Yang X. Determination of the water-use patterns for two xerophyte shrubs by hydrogen isotope offset correction. TREE PHYSIOLOGY 2024; 44:tpad124. [PMID: 37769327 DOI: 10.1093/treephys/tpad124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/11/2023] [Accepted: 09/24/2023] [Indexed: 09/30/2023]
Abstract
The stable hydrogen and oxygen isotope technique is typically used to explore plant water uptake; however, the accuracy of the technique has been challenged by hydrogen isotope offsets between plant xylem water and its potential source water. In this study, the soil hydrogen and oxygen isotope waterline was used to correct the hydrogen isotope offsets for Salix psammophila and Caragana korshinskii, two typical shrub species on the Chinese Loess Plateau. Five different types of isotopic data [(i) δ18O, (ii) δ2H, (iii) combination δ18O with δ2H, (iv) corrected δ2H and (v) combination δ18O with corrected δ2H] were separately used to determine the water-use patterns of the two shrubs. The δ2H offset values of S. psammophila and C. korshinskii did not show significant temporal variation among the sampling months (May, July and September) but showed notable differences between the two shrubs (-0.4 ± 0.5‰ in S. psammophila vs -4.3 ± 0.9‰ in C. korshinskii). The obtained water absorption proportion (WAP) of S. psammophila in the different soil layers (0-20, 20-60 and 60-200 cm) did not differ significantly among the five different input data types. However, compared with the input data types (iii) and (v), the data types (i), (ii) and (iv) overestimated the WAP of C. korshinskii in the 0-20 cm soil layer and underestimated that in the 60-200 cm layer. The data type (iii) overestimated the WAP of C. korshinskii in 0-20 cm soil layer (25.9 ± 0.8%) in July in comparison with the WAP calculated based on data type (v) (19.1 ± 1.1%). The combination of δ18O and corrected δ2H, i.e., data type (v), was identified as the best data type to determine the water use patterns of C. korshinskii due to the strong correlation between the calculated WAP and soil water content and soil sand content. In general, S. psammophila mainly used (57.9-62.1%) shallow soil water (0-60 cm), whereas C. korshinskii mainly absorbed (52.7-63.5%) deep soil water (60-200 cm). We confirm that the hydrogen isotope offsets can cause significant errors in determining plant water uptake of C. korshinskii, and provide valuable insights for accurately quantifying plant water uptake in the presence of hydrogen isotope offsets between xylem and source water. This study is significant for facilitating the application of the stable hydrogen and oxygen isotope technique worldwide, and for revealing the response mechanism of shrub key ecohydrological and physiological processes to the drought environment in similar climate regions.
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Affiliation(s)
- Zhixue Chen
- College of Pastoral Agriculture Science and Technology, Lanzhou University, No. 768 Jiayuguanxi Road, Lanzhou, Gansu, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, Lanzhou University, No. 768 Jiayuguanxi Road, Lanzhou, Gansu, China
| | - Guohui Wang
- Key Laboratory for Model Innovation in Forage Production Efficiency, Ministry of Agriculture and Rural Affairs, Ningxia University, No. 489 Helan West Road, Yinchuan, Ningxia, China
| | - Yanhui Pan
- Key Laboratory of Western China's Environmental Systems, Ministry of Education, Lanzhou University, No. 222 Tianshui South Road, Lanzhou, Gansu, China
| | - Yuying Shen
- College of Pastoral Agriculture Science and Technology, Lanzhou University, No. 768 Jiayuguanxi Road, Lanzhou, Gansu, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, Lanzhou University, No. 768 Jiayuguanxi Road, Lanzhou, Gansu, China
| | - Xianlong Yang
- College of Pastoral Agriculture Science and Technology, Lanzhou University, No. 768 Jiayuguanxi Road, Lanzhou, Gansu, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, Lanzhou University, No. 768 Jiayuguanxi Road, Lanzhou, Gansu, China
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Huynh A, Aguirre BA, English J, Guzman D, Wright AJ. Atmospheric drying and soil drying: Differential effects on grass community composition. GLOBAL CHANGE BIOLOGY 2024; 30:e17106. [PMID: 38273553 DOI: 10.1111/gcb.17106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 12/01/2023] [Accepted: 12/08/2023] [Indexed: 01/27/2024]
Abstract
Global surface temperatures are projected to increase in the future; this will modify regional precipitation regimes and increase global atmospheric drying. Despite many drought studies examining the consequences of reduced precipitation, there are few experimental studies exploring plant responses to atmospheric drying via relative humidity and vapor pressure deficit (VPD). We examined eight native California perennial grass species grown in pots in a greenhouse in Los Angeles, California for 34 weeks. All pots were well-watered for 21 weeks, at which point we reduced watering to zero and recorded daily growth and dormancy for 3 weeks. We used this information to better understand the drought tolerance of our species in a larger soil drying × atmospheric drying experiment. In this larger experiment, we grew all eight species together in outdoor mesocosms and measured changes in community composition after 4 years of growth. Soil drying in our small pot experiment mirrored compositional shifts in the larger experiment. Namely, our most drought-tolerant species in our pot experiment was Poa secunda, due to a summer dormancy strategy. Similarly, the grass community shifted toward P. secunda in the driest soils as P. secunda was mostly unaffected by either soil drying or atmospheric drying. We found that some species responded strongly to soil drying (Elymus glaucus, Festuca idahoensis, and Hordeum b. californicum), while others responded strongly to atmospheric drying (Bromus carinatus and Stipa cernua). As result, community composition shifted in different and interacting ways in response to soil drying, atmospheric drying, and their combination. Further study of community responses to increasing atmospheric aridity is an essential next step to predicting the future consequences of climate change.
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Affiliation(s)
- A Huynh
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA
| | - B A Aguirre
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
| | - J English
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - D Guzman
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA
| | - A J Wright
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA
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Huang F, Liu L, Gao J, Yin Z, Zhang Y, Jiang Y, Zuo L, Fang W. Effects of extreme drought events on vegetation activity from the perspectives of meteorological and soil droughts in southwestern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166562. [PMID: 37633390 DOI: 10.1016/j.scitotenv.2023.166562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/20/2023] [Accepted: 08/23/2023] [Indexed: 08/28/2023]
Abstract
Under climate warming, extreme drought events (EDEs) in southwestern China have become more frequent and severe and have had significant impacts on vegetation growth. Clarifying the influence of soil and meteorological droughts on the vegetation photosynthetic rate (PHR) and respiration rate (RER) can help policymakers to anticipate the impacts of drought on vegetation and take measures to reduce losses. In this study, the frequency and features of EDEs from 1990 to 2021 were analyzed using the standardized precipitation evapotranspiration index, and the longest-lasting and most severe EDE was chosen to assess the effects of drought on vegetation activity. Then, a land surface model was used to simulate the vegetation PHR and RER. Finally, the effects of the EDE on the vegetation PHR and RER were analyzed from the perspectives of soil and meteorological droughts. The results revealed that from 1990 to 2021, a total of 11 EDEs were observed in southwestern China, and the longest-lasting and most severe EDE occurred in 2009-2010 (EDE2009/2010). EDE2009/2010 significantly reduced the monthly mean PHR and RER by 9.82 g C m-2 month-1 and 0.80 g C m-2 month-1, respectively, causing a cumulative reduction of approximately 5.61 × 1013 g C. Soil and meteorological droughts had a driving force of 39 % on the PHR changes and an explanatory force of 42 % on the RER reduction. In particular, the soil drought had an average explanatory force of 25 % on the PHR and made a contribution of 24 % to the RER. The drought affected different types of vegetation differently, and crops were more susceptible than grassland and forests on the monthly time scale. The vegetation exhibited resilience to drought, returning to normal PHR and RER levels 2 months after the end of EDE2009/2010. This research contributes to understanding and predicting the impact of EDEs on vegetation growth in southwestern China.
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Affiliation(s)
- Fengxian Huang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lulu Liu
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Jiangbo Gao
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Academy of Plateau Science and Sustainability, People's Government of Qinghai Province & Beijing Normal University, Qinghai Normal University, Xining 810008, China.
| | - Ziying Yin
- China University of Geosciences (Beijing), Beijing 100083, China
| | - Yibo Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuan Jiang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liyuan Zuo
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenguo Fang
- School of Geographic Science, Qinghai Normal University, Xining 810016, China
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Hao L, Liu X, Ji R, Ma Y, Wu P, Cao Q, Xin Y. Indirect regulation of topsoil nutrient cycling by groundwater depth: impacts on sand-fixing vegetation and rhizosphere bacterial communities. Front Microbiol 2023; 14:1285922. [PMID: 38143862 PMCID: PMC10746847 DOI: 10.3389/fmicb.2023.1285922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/09/2023] [Indexed: 12/26/2023] Open
Abstract
Introduction The impact of groundwater table depth (GTD) on bacterial communities and soil nutrition in revegetated areas remains unclear. Methods We investigated the impacts of plant growth and soil physicochemical factors on rhizosphere bacterial communities under different GTD. Results The four plant growth indices (Pielou, Margalef, Simpson, and Shannon-Wiener indices) and soil water content (SWC) at the Artem and Salix sites all showed a decreasing trend with increasing GTD. Salix had a higher nutrient content than Artem. The response of plant rhizosphere bacterial communities to GTD changes were as follows. Rhizosphere bacteria at the Artem and Salix sites exhibited higher relative abundance and alpha diversity in SW (GTD < 5 m) compared than in DW (GTD > 5 m). Functional microbial predictions indicated that the rhizosphere bacterial communities of Artem and Salix promoted carbon metabolism in the SW. In contrast, Artem facilitated nitrogen cycling, whereas Salix enhanced both nitrogen cycling and phototrophic metabolism in the DW. Discussion Mantel test analysis revealed that in the SW of Artem sites, SWC primarily governed the diversity of rhizosphere and functional bacteria involved in the nitrogen cycle by affecting plant growth. In DW, functional bacteria increase soil organic carbon (SOC) to meet nutrient demands. However, higher carbon and nitrogen availability in the rhizosphere soil was observed in the SW of the Salix sites, whereas in DW, carbon nutrient availability correlated with keystone bacteria, and changes in nitrogen content could be attributed to nitrogen mineralization. This indicates that fluctuations in the groundwater table play a role in regulating microbes and the distribution of soil carbon and nitrogen nutrients in arid environments.
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Affiliation(s)
- Lianyi Hao
- School of Water and Environment, Chang’an University, Xi’an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang’an University, Xi’an, China
- Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Region of Ministry of Water Resources, Chang’an University, Xi’an, China
| | - Xiuhua Liu
- School of Water and Environment, Chang’an University, Xi’an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang’an University, Xi’an, China
- Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Region of Ministry of Water Resources, Chang’an University, Xi’an, China
| | - Ruiqing Ji
- School of Water and Environment, Chang’an University, Xi’an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang’an University, Xi’an, China
- Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Region of Ministry of Water Resources, Chang’an University, Xi’an, China
| | - Yandong Ma
- Key Laboratory of State Forest Administration on Soil and Water Conservation & Ecological Restoration of Loess Plateau, Shaanxi Academy of Forestry, Xi’an, China
| | - Puxia Wu
- Key Laboratory of State Forest Administration on Soil and Water Conservation & Ecological Restoration of Loess Plateau, Shaanxi Academy of Forestry, Xi’an, China
| | - Qingxi Cao
- Key Laboratory of State Forest Administration on Soil and Water Conservation & Ecological Restoration of Loess Plateau, Shaanxi Academy of Forestry, Xi’an, China
| | - Yunling Xin
- Key Laboratory of State Forest Administration on Soil and Water Conservation & Ecological Restoration of Loess Plateau, Shaanxi Academy of Forestry, Xi’an, China
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El-Hokayem L, De Vita P, Usman M, Link A, Conrad C. Mapping potentially groundwater-dependent vegetation in the Mediterranean biome using global geodata targeting site conditions and vegetation characteristics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:166397. [PMID: 37598963 DOI: 10.1016/j.scitotenv.2023.166397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/25/2023] [Accepted: 08/15/2023] [Indexed: 08/22/2023]
Abstract
Groundwater-dependent vegetation (GDV) is essential for maintaining ecosystem functions and services, providing critical habitat for species, and sustaining human livelihoods. However, climate and land-use change are threatening GDV, highlighting the need for harmonised, global mapping of the distribution and extent of GDV. This need is particularly crucial in vulnerable biodiversity hotspots such as the Mediterranean biome. This study presents a novel multicriteria index to identify areas in the Mediterranean biome that provide suitable environmental conditions to support potentially groundwater-dependent vegetation (pGDV) where vegetation behaviour is also indicative of groundwater use. Global datasets targeting 1) groundwater vegetation interaction; 2) soil water holding capacity; 3) topographical landscape wetness potential; 4) land use land cover and 5) hydraulic conductivity of rocks have been combined for the first time in an easy-to-use index. Layer weightings from Analytical Hierarchy Process and Random Forest showed limited applicability on biome scale, but an unweighted overlay of eleven thematic layers produced plausible results. The final pGDV map indicates that 31 % of the natural vegetation in the Mediterranean biome likely depend on groundwater. Moreover, moderate to good agreement was found compared to actual GDV locations in Campania, Italy (91 % with at least moderate potential) and California, USA (87 % with at least moderate potential). The results provide valuable information for identifying regions with a substantial presence of pGDV in the Mediterranean biome and can be used for decision making, e.g. to prioritise field surveys and high-resolution remote sensing for GDV mapping. It can therefore support effective groundwater resource management and the conservation of biodiversity hotspots.
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Affiliation(s)
- Léonard El-Hokayem
- Institute of Geosciences and Geography, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig 04103, Germany.
| | - Pantaleone De Vita
- Department of Earth, Environmental and Resources Sciences, University of Naples Federico II, Naples 80126, Italy
| | - Muhammad Usman
- Institute of Geosciences and Geography, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany
| | - Andreas Link
- Chair of Sustainable Engineering, Technical University of Berlin, Berlin 10623, Germany
| | - Christopher Conrad
- Institute of Geosciences and Geography, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig 04103, Germany
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11
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Chen L, Li M, Li C, Zheng W, Liu R. Different Physiological Responses to Continuous Drought between Seedlings and Younger Individuals of Haloxylon ammodendron. PLANTS (BASEL, SWITZERLAND) 2023; 12:3683. [PMID: 37960040 PMCID: PMC10647405 DOI: 10.3390/plants12213683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/18/2023] [Accepted: 10/18/2023] [Indexed: 11/15/2023]
Abstract
Drought is an important environmental factor that influences physiological processes in plants; however, few studies have examined the physiological mechanisms underlying plants' responses to continuous drought. In this study, the seedlings and younger individuals of Haloxylon ammodendron were experimentally planted in the southern part of the Gurbantunggut Desert. We measured their photosynthetic traits, functional traits and non-structural carbohydrate contents (NSCs) in order to assess the effects of continuous drought (at 15-day and 30-day drought points) on the plants' physiological responses. The results showed that at the 15-day (15 d) drought point, the leaf light-saturated net photosynthetic rate (An) values of both the seedlings and the younger individuals were decreased (by -68.9% and -45.2%, respectively). The intrinsic water use efficiency (iWUE) of the seedlings was significantly lower than that of the control group (-52.2%), but there was no diffenrence of iWUE observed in younger individuals. At the 30-day (30 d) drought point, a decrease in the An (-129.8%) of the seedlings was induced via biochemical inhibition, with a lower potential maximum photochemical rate (Fv/Fm, 0.42) compared with the control group, while a decrease in the An (-52.3%) of the younger individuals was induced due to lower stomatal conductance (gs, -50.5%). Our results indicated that prolonged drought induced a greater risk of seedling mortality as the relatively limited ability of stomatal regulation may increase the possibility of massive embolism, resulting in hydraulic failure.
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Affiliation(s)
- Lidan Chen
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (L.C.); (M.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Fukang 831505, China
| | - Minqing Li
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (L.C.); (M.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- Fukang National Station of Observation and Research for Desert Ecosystem, Fukang 831505, China
| | - Congjuan Li
- National Engineering Technology Research Center for Desert-Oasis Ecological Construction, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China;
| | - Weihua Zheng
- Institute of Agricultural Quality Standards and Testing Technology, Xinjiang Academy of Agricultural Sciecnes, Urumuqi 830091, China;
| | - Ran Liu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; (L.C.); (M.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Li Q, Liu X, Sun X, Zhao M, Liu L, Wang N, Gao Q, Fan P, Du N, Wang H, Wang R. Effects of drought hardening on the carbohydrate dynamics of Quercus acutissima seedlings under successional drought. FRONTIERS IN PLANT SCIENCE 2023; 14:1184584. [PMID: 37692418 PMCID: PMC10485557 DOI: 10.3389/fpls.2023.1184584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023]
Abstract
Introduction As precipitation patterns are predicted to become increasingly erratic, the functional maintenance of warm-temperate forests constitutes a key challenge for forest managers. In this study, 2-year-old Quercus acutissima seedlings were selected to elucidate the mechanisms whereby they respond to soil water fluctuations and the drought hardening effects on plant carbohydrate dynamics. Methods Seedlings were trained under different soil water conditions for 2 months: drought (D), well-watered (W), 1-month drought and then 1-month well-watered (D-W), and 1-month well-watered and then 1-month drought (W-D). The functional traits involved in water- and carbon-use strategies were explored at the end of the hardening period. Compared with seedlings in group W, seedlings in groups D, D-W, and W-D had increased potential for carbon uptake (i.e., light saturated point, maximum ribulose-1,5-bisphosphate (RuBP) saturated rate, and electron transport rate) and water uptake (i.e., fine root-to-coarse root ratio) and downregulated growth and mitochondrial respiration to decrease carbon consumption. After water fluctuation hardening, we performed a successional dry-down experiment for 1 month to detect carbohydrate dynamics and explore the acclimation caused by prior hardening. Results and discussion Our results revealed that there were more soluble sugars allocated in the leaves and more starch allocated in the stems and roots of seedlings hardened in the D, W-D, and D-W treatments than that of seedlings hardened in the W treatment. No significant changes in total non-structural carbohydrates were found. In addition, we found near-zero (seedlings trained by D and D-W treatments) or negative (seedlings trained by W-D treatment) growth of structural biomass at the end of the dry-down experiment, which was significantly lower than that of W-hardened seedlings. This suggests that there was a shift in allocation patterns between carbon storage and growth under recurrent soil drought, which can be strengthened by drought memory. We conclude that Q. acutissima seedlings adjusted water- and carbon-use strategies in response to water fluctuations, whereas stress memory can enhance their overall performance in reoccurring drought. Therefore, taking advantage of stress memory is a promising management strategy in forest nurseries, and drought-trained seedlings might be more suitable for afforestation practices in sites characterized by fluctuating soil water content, considering the ongoing global climatic changes.
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Affiliation(s)
- Qiang Li
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- School of Tropical Medicine, Hainan Medical University, Haikou, China
| | - Xiao Liu
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Qingdao Key Laboratory of Forest and Wetland Ecology, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
| | - Xinke Sun
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
| | - Mingming Zhao
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
| | - Lele Liu
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
| | - Ning Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Qingdao Key Laboratory of Forest and Wetland Ecology, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
| | - Qun Gao
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Qingdao Key Laboratory of Forest and Wetland Ecology, Shandong University, Qingdao, China
| | - Peixian Fan
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Qingdao Key Laboratory of Forest and Wetland Ecology, Shandong University, Qingdao, China
| | - Ning Du
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
| | - Hui Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Qingdao Key Laboratory of Forest and Wetland Ecology, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
| | - Renqing Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Shandong University, Qingdao, China
- Qingdao Key Laboratory of Forest and Wetland Ecology, Shandong University, Qingdao, China
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao, China
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Martín-Gómez P, Rodríguez-Robles U, Ogée J, Wingate L, Sancho-Knapik D, Peguero-Pina J, Dos Santos Silva JV, Gil-Pelegrín E, Pemán J, Ferrio JP. Contrasting stem water uptake and storage dynamics of water-saver and water-spender species during drought and recovery. TREE PHYSIOLOGY 2023; 43:1290-1306. [PMID: 36930058 DOI: 10.1093/treephys/tpad032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 03/01/2023] [Accepted: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Drought is projected to occur more frequently and intensely in the coming decades, and the extent to which it will affect forest functioning will depend on species-specific responses to water stress. Aiming to understand the hydraulic traits and water dynamics behind water-saver and water-spender strategies in response to drought and recovery, we conducted a pot experiment with two species with contrasting physiological strategies, Scots pine (Pinus sylvestris L.) and Portuguese oak (Quercus faginea L.). We applied two cycles of soil drying and recovery and irrigated with isotopically different water to track fast changes in soil and stem water pools, while continuously measuring physiological status and xylem water content from twigs. Our results provide evidence for a tight link between the leaf-level response and the water uptake and storage patterns in the stem. The water-saver strategy of pines prevented stem dehydration by rapidly closing stomata which limited their water uptake during the early stages of drought and recovery. Conversely, oaks showed a less conservative strategy, maintaining transpiration and physiological activity under dry soil conditions, and consequently becoming more dehydrated at the stem level. We interpreted this dehydration as the release of water from elastic storage tissues as no major loss of hydraulic conductance occurred for this species. After soil rewetting, pines recovered pre-drought leaf water potential rapidly, but it took longer to replace the water from conductive tissues (slower labeling speed). In contrast, water-spender oaks were able to quickly replace xylem water during recovery (fast labeling speed), but it took longer to refill stem storage tissues, and hence to recover pre-drought leaf water potential. These different patterns in sap flow rates, speed and duration of the labeling reflected a combination of water-use and storage traits, linked to the leaf-level strategies in response to drought and recovery.
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Affiliation(s)
- Paula Martín-Gómez
- Joint Research Unit CTFC - AGROTECNIO - CERCA, Ctra de Sant Llorenç de Morunys, km 2, E-25280 Solsona, Lleida, Spain
| | - Ulises Rodríguez-Robles
- Departamento de Ecología y Recursos Naturales, Centro Universitario de la Costa Sur, Universidad de Guadalajara, Av. Independencia Nacional 151, Autlán de Navarro, 48900 Jalisco, México
| | - Jérôme Ogée
- Atmosphere Plant Soil Interactions Research Unit (UMR ISPA), Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), 71 Av. Edouard Bourlaux, F-33140 Villenave d'Ornon, France
| | - Lisa Wingate
- Atmosphere Plant Soil Interactions Research Unit (UMR ISPA), Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), 71 Av. Edouard Bourlaux, F-33140 Villenave d'Ornon, France
| | - Domingo Sancho-Knapik
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda. Montañana 930, E-50059 Zaragoza, Spain
| | - José Peguero-Pina
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda. Montañana 930, E-50059 Zaragoza, Spain
| | - José Victor Dos Santos Silva
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda. Montañana 930, E-50059 Zaragoza, Spain
| | - Eustaquio Gil-Pelegrín
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda. Montañana 930, E-50059 Zaragoza, Spain
| | - Jesús Pemán
- Department of Crop and Forest Sciences, Universitat de Lleida (UdL), Av. Alcalde Rovira Roure 191, 25198 Lleida, Spain
| | - Juan Pedro Ferrio
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda. Montañana 930, E-50059 Zaragoza, Spain
- Aragon Agency for Research and Development (ARAID), E-50018 Zaragoza, Spain
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14
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Wu X, Wang X, Wang P, Gu Y, Li Y. Effects of groundwater depth on ecological stoichiometric characteristics of assimilated branches and soil of two desert plants. FRONTIERS IN PLANT SCIENCE 2023; 14:1225907. [PMID: 37615016 PMCID: PMC10443709 DOI: 10.3389/fpls.2023.1225907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 07/07/2023] [Indexed: 08/25/2023]
Abstract
Groundwater plays a crucial role in regulating plant growth in arid regions and has significant effects on plant physiological mechanisms. However, research on the influence of groundwater change on plant ecological stoichiometry is still limited. Therefore, this study was carried out to obtain the variations in assimilated branches and soil ecological stoichiometry of two dominant species in the Gurbantunggut Desert (Haloxylon ammodendron and Haloxylon persicum) at different groundwater depths to reveal the responses of desert plants to groundwater depth changes. The results showed that (1) H. persicum branches' stress tolerance indicators (C:N, C:P) are higher, while nutritional indicators (N:P) are lower. The soil nutrient of H. ammodendron is richer. (2) The ecological stoichiometry varied significantly along the groundwater gradient. With the deepening of groundwater, the branches C, N and P increased, and the variation in element ratio was inconsistent. Most of the soil properties was inversely proportional to the depth of groundwater. (3) Groundwater depth was a vital environmental factor affecting the assimilated branches ecological stoichiometry. Soil properties also had a significant influence on element accumulation in assimilated branches. (4) Regulating the allocation of branches ecological stoichiometry is an adaptation of two Haloxylon species to cope with local hydrological conditions changes. These findings provide novel insights into desert plant responses to different groundwater conditions within fragile desert ecosystems and may have implications for the implementation of effective measures related to the stability and sustainability of desert ecosystems.
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Affiliation(s)
- Xue Wu
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Key Laboratory of Oasis Ecology, Ministry of Education, Urumqi, China
- Ecological Postdoctoral Research Station, Xinjiang University, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Jinghe, China
| | - Xueying Wang
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Key Laboratory of Oasis Ecology, Ministry of Education, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Jinghe, China
| | - Pengqi Wang
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Key Laboratory of Oasis Ecology, Ministry of Education, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Jinghe, China
| | - Yuanting Gu
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Key Laboratory of Oasis Ecology, Ministry of Education, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Jinghe, China
| | - Yan Li
- Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
- Fukang Station of Desert Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
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15
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Goodwin MJ, Kerhoulas LP, Zald HSJ, North MP, Hurteau MD. Conifer water-use patterns across temporal and topographic gradients in the southern Sierra Nevada. TREE PHYSIOLOGY 2023; 43:210-220. [PMID: 36263988 DOI: 10.1093/treephys/tpac124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
Climate change is increasing the severity and duration of drought events experienced by forest ecosystems. Because water is essential for tree physiological processes, the ability of trees to survive prolonged droughts will largely depend on whether they have access to reliable water sources. While many woody plant species exhibit the ability to shift water sources between different depths of soil and rock water in response to changes in climate and water availability, it is unclear if Sierra Nevada conifers exhibit this plasticity. Here we analysed the δ18O and δ13C values of annual tree rings to determine the water-use patterns of large Sierra Nevada conifers during the 2012-16 California drought and 4 years before this drought event (2004-07). We analysed four species (Pinus jeffreyi Grev. & Balf. (Jeffrey pine), Pinus lambertiana Dougl. (sugar pine), Abies concolor (Gord. & Glend.) Lindl. Ex Hilderbr (white fir) and Calocedrus decurrens (Torr.) Florin (incense-cedar)) across a range of topographic positions to investigate differences in water-use patterns by species and position on the landscape. We found no significant differences in δ18O and δ13C values for the pre-drought and drought periods. This stability in δ18O values suggests that trees did not shift their water-use patterns in response to the 2012-16 drought. We did find species-specific differences in water-use patterns, with incense-cedar exhibiting more depleted δ18O values than all other species. We also found trends that suggest the water source used by a tree may depend on topographic and growing environment attributes such as topographic wetness and the surrounding basal area. Overall, our results suggest that the water source used by trees varies by the species and topographic position, but that Sierra Nevada conifers do not switch their water-use patterns in response to the drought. This lack of plasticity could make Sierra Nevada conifers particularly vulnerable to drought mortality as their historically reliable water sources begin to dry out with climate change.
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Affiliation(s)
- Marissa J Goodwin
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Lucy P Kerhoulas
- Department of Forestry and Wildland Resources, California State Polytechnic University, Humboldt, Arcata, CA 95521, USA
| | - Harold S J Zald
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR 97331, USA
| | - Malcolm P North
- USDA Forest Service, Pacific Southwest Research Station, Mammoth Lakes, CA 93546, USA
| | - Matthew D Hurteau
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
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16
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Qin J, Si J, Jia B, Zhao C, Zhou D, He X, Wang C, Zhu X. Water use strategies of Ferula bungeana on mega-dunes in the Badain Jaran Desert. FRONTIERS IN PLANT SCIENCE 2022; 13:957421. [PMID: 36561438 PMCID: PMC9763701 DOI: 10.3389/fpls.2022.957421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/16/2022] [Indexed: 06/17/2023]
Abstract
In desert ecosystems, ephemeral plants have developed specialized water use strategies in response to long-term natural water stress. To examine the water use strategies of desert ephemeral plants under natural extreme drought conditions, we investigated the water absorption sources, water potential, hydraulic conductivity, and water use efficiency of Ferula bungeana at different elevations on the slopes of mega-dunes in the Badain Jaran Desert, Inner Mongolia, during a period of extreme drought. We found that the water utilized by F. bungeana was mostly absorbed from the 0-60 cm soil layers (80.47 ± 4.28%). With progression of the growing season, the source of water changed from the 0-30 cm soil layer to the 30-60 cm layer. The water potentials of the leaves, stems, and roots of F. bungeana were found to be characterized by clear diurnal and monthly variation, which were restricted by water availability and the hydraulic conductivity of different parts of the plant. The root hydraulic conductivity of F. bungeana was found to be considerably greater than that of the canopy, both of which showed significant diurnal and monthly variation. The water use efficiency of F. bungeana under extreme drought conditions was relatively high, particularly during the early and late stages of the growing season. Variations in water availability led to the regulation of water uptake and an adjustment of internal water conduction, which modified plant water use efficiency. These observations tend to indicate that the water use strategies of F. bungeana are mainly associated with the growth stage of plants, whereas the distribution pattern of plants on mega-dunes appeared to have comparatively little influence. Our findings on the water use of ephemeral plants highlight the adaptive mechanisms of these plants in desert habitats and provide a theoretical basis for selecting plants suitable for the restoration and reconstruction of desert ecosystems.
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Affiliation(s)
- Jie Qin
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jianhua Si
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Bing Jia
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chunyan Zhao
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Dongmeng Zhou
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaohui He
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chunlin Wang
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xinglin Zhu
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
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17
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Urrutia-Jalabert R, Barichivich J, Szejner P, Rozas V, Lara A. Ecophysiological responses of Nothofagus obliqua forests to recent climate drying across the Mediterranean-Temperate biome transition in south-central Chile. JOURNAL OF GEOPHYSICAL RESEARCH. BIOGEOSCIENCES 2022; 128:2022jg007293. [PMID: 37484604 PMCID: PMC7614787 DOI: 10.1029/2022jg007293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 03/02/2023] [Indexed: 07/25/2023]
Abstract
The forests of south-central Chile are facing a drying climate and a megadrought that started in 2010. This study addressed the physiological responses of five Nothofagus obliqua stands across the Mediterranean-Temperate gradient (35.9 ° -40.3° S) using carbon isotope discrimination (Δ13 C) and intrinsic water use efficiency (iWUE) in tree rings during 1967-2017. Moreover, δ18O was evaluated in the northernmost site to better understand the effects of the megadrought in this drier location. These forests have become more efficient in their use of water. However, trees from the densest stand are discriminating more against 13C, probably due to reduced photosynthetic rates associated with increasing competition. The strongest associations between climate and Δ13C were found in the northernmost stand, suggesting that warmer and drier conditions could have reduced 13C discrimination. Tree growth in this site has not decreased, and δ18O was negatively related to annual rainfall. However, a shift in this relationship was found since 2007, when both precipitation and δ18O decreased, while correlations between δ18O and growth increased. This implies that tree growth and δ18O are coupled in recent years, but precipitation is not the cause, suggesting that trees probably changed their water source to deeper and more depleted pools. Our research demonstrates that forests are not reducing their growth in central Chile, mainly due to a shift towards the use of deeper water sources. Despite a common climate trend across the gradient, there is a non-uniform response of N. obliqua forests to climate drying, being their response site specific. Keywords: Tree rings, stable isotopes, tree physiology, climate gradient, megadrought, climate change.
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Affiliation(s)
- Rocío Urrutia-Jalabert
- Departamento de Ciencias Naturales y Tecnología, Universidad de Aysén, Coyhaique, Chile
- Laboratorio de Dendrocronología y Cambio Global, Instituto de Conservación, Biodiversidad y Territorio, Facultad de Ciencias Forestales y Recursos Naturales, Universidad Austral de Chile, Valdivia, Chile
- Centro de Ciencia del Clima y la Resiliencia, CR2, Santiago, Chile
| | - Jonathan Barichivich
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CRNS/CEA/UVSQ, France
- Instituto de Geografía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Paul Szejner
- Departamento de Ciencias Ambientales y del suelo, Instituto de Geología, Universidad Nacional Autónoma de México. Ciudad Universitaria CDMX, México
| | - Vicente Rozas
- iuFOR-EiFAB, Área de Botánica, Campus Duques de Soria, Universidad de Valladolid, 42004 Soria, Spain
| | - Antonio Lara
- Laboratorio de Dendrocronología y Cambio Global, Instituto de Conservación, Biodiversidad y Territorio, Facultad de Ciencias Forestales y Recursos Naturales, Universidad Austral de Chile, Valdivia, Chile
- Centro de Ciencia del Clima y la Resiliencia, CR2, Santiago, Chile
- Fundación Centro de los Bosques Nativos FORECOS, Valdivia, Chile
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Jiang H, Gu H, Chen H, Sun H, Zhang X, Liu X. Comparative cryogenic extraction rehydration experiments reveal isotope fractionation during root water uptake in Gramineae. THE NEW PHYTOLOGIST 2022; 236:1267-1280. [PMID: 35945699 DOI: 10.1111/nph.18423] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Determining whether isotope fractionation occurs during root water uptake is a prerequisite for using stem or xylem water isotopes to trace water sources. However, it is unclear whether isotope fractionation occurs during root water uptake in gramineous crops. We conducted prevalidation experiments to estimate the isotope measurement bias associated with cryogenic vacuum distillation (CVD). Next, we assessed isotope fractionation during root water uptake in two common agronomic crops, wheat (Triticum aestivum L.) and maize (Zea mays L.), under flooding after postdrought stress conditions. Cryogenic vacuum distillation caused significant depletion of 2 H but negligible effects on 18 O for both soil and stem water. Surprisingly CVD caused depletion of 2 H and enrichment of 18 O in root water. Stem and root water δ18 O were more than soil water δ18 O, even considering the uncertainty of CVD. Soil water 18 O was depleted compared with irrigation water 18 O in the pots with plants but enriched relative to irrigation water 18 O in the pots without plants. These results indicate that isotope fractionation occurred during wheat and maize root water uptake after full irrigation and led to a heavy isotope enrichment in stem water. Therefore, the xylem/stem water isotope approach widely used to trace water sources should be carefully evaluated.
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Affiliation(s)
- Hanbing Jiang
- Key Laboratory of Agricultural Water Resources, the Innovative Academy of Seed Design, the Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Shijiazhuang, 050021, Hebei, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Huijie Gu
- Key Laboratory of Agricultural Water Resources, the Innovative Academy of Seed Design, the Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Shijiazhuang, 050021, Hebei, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Hui Chen
- College of Geographical Sciences, Hebei Normal University, Shijiazhuang, 050016, Hebei, China
| | - Hongyong Sun
- Key Laboratory of Agricultural Water Resources, the Innovative Academy of Seed Design, the Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Shijiazhuang, 050021, Hebei, China
| | - Xiying Zhang
- Key Laboratory of Agricultural Water Resources, the Innovative Academy of Seed Design, the Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Shijiazhuang, 050021, Hebei, China
| | - Xiuwei Liu
- Key Laboratory of Agricultural Water Resources, the Innovative Academy of Seed Design, the Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Shijiazhuang, 050021, Hebei, China
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19
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Zhang Y, Xu Q, Zhang B, Gao D, Wang T, Xu W, Ren R, Wang S. Contrasting water-use patterns of Chinese fir among different plantation types in a subtropical region of China. FRONTIERS IN PLANT SCIENCE 2022; 13:946508. [PMID: 36186060 PMCID: PMC9520624 DOI: 10.3389/fpls.2022.946508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/29/2022] [Indexed: 06/16/2023]
Abstract
Plantation cultivation plays an important role in improving terrestrial ecosystem functions and services. Understanding the water-use patterns of major afforestation species is vital for formulating ecological restoration strategies and predicting the response of plantation to climate change. However, the impacts and drivers of forest types on water-use patterns of key tree species are poorly understood. Here, the combined methods of dual stable isotope of δD and δ 18O and Bayesian mixed framework (MixSIAR) were employed to investigate the water-use patterns of Cunninghamia lanceolata (Chinese fir) in a monoculture, mixed forest with Cinnamomum camphora, and mixed forest with Alnus cremastogyne under different rainfall events in subtropical China. Furthermore, the relative contribution of different soil and plant factors to the water-use patterns of Chinese fir was quantified using a random forest model. Our results showed that Chinese fir in the mixed forests (with C. camphora or with A. cremastogyne) utilized less water from shallow soil compared to that in a monoculture but significantly improved the proportion of water absorbed from deep soil with the increase of 55.57%-64.90% and 68.99%-108.83% following moderate and heavy rainfall events, respectively. The most important factors contributing to the differences in water-use patterns of Chinese fir among monoculture and mixed forests were tree attributes (i.e., leaf biomass, eco-physiological regulation, and fine root biomass). These findings reveal that Chinese fir in mixed forests could optimize water-use patterns by adjusting plant properties for interspecific niche complementarity, improving the utilization of deep soil water. Overall, this study suggests that mixed-species plantations could improve water-use efficiency and reduce the sensitivity of tree species to precipitation change, indicating they are better able to cope with expected climate variability.
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Affiliation(s)
- Ying Zhang
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Qing Xu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Beibei Zhang
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Deqiang Gao
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Ting Wang
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Wenbin Xu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Ranran Ren
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Silong Wang
- Huitong Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
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20
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Key Strategies Underlying the Adaptation of Mongolian Scots Pine (Pinussylvestris var. mongolica) in Sandy Land under Climate Change: A Review. FORESTS 2022. [DOI: 10.3390/f13060846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Forest degradation and mortality have been widely reported in the context of increasingly significant global climate change. As the country with the largest total tree plantation area globally, China has a great responsibility in forestry management to cope with climate change effectively. Mongolian Scots pine (Pinus sylvestris var. mongolica) was widely introduced from its natural sites in China into several other sandy land areas for establishing shelterbelt in the Three-North Shelter Forest Program, scoring outstanding achievements in terms of wind-breaking and sand-fixing. Mongolian Scots pine plantations in China cover a total area of ~800,000 hectares, with the eldest trees having >60 years. However, plantation trees have been affected by premature senescence in their middle-age stages (i.e., dieback, growth decline, and death) since the 1990s. This phenomenon has raised concerns about the suitability of Mongolian Scots pine to sandy habitats and the rationality for further afforestation, especially under the global climate change scenario. Fortunately, dieback has occurred only sporadically at specific sites and in certain years and has not spread to other regions in northern China; nevertheless, global climate change has become increasingly significant in that region. These observations reflect the strong drought resistance and adaptability of Mongolian Scots pines. In this review, we summarized the most recent findings on the ecohydrological attributes of Mongolian Scots pine during its adaptation to both fragile habitats and climate change. Five main species-specific strategies (i.e., opportunistic water absorb strategy, hydraulic failure risk avoidance strategy, water conservation strategy, functional traits adjustment strategy, rapid regeneration strategy) were summarized, providing deep insights into the tree–water relationship. Overall, the findings of this study can be applied to improve plantation management and better cope with climate-change-related drought stress.
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Češljar G, Jovanović F, Brašanac-Bosanac L, Đorđević I, Mitrović S, Eremija S, Ćirković-Mitrović T, Lučić A. Impact of an Extremely Dry Period on Tree Defoliation and Tree Mortality in Serbia. PLANTS (BASEL, SWITZERLAND) 2022; 11:1286. [PMID: 35631711 PMCID: PMC9144404 DOI: 10.3390/plants11101286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 11/16/2022]
Abstract
This paper presents research results on forest decline in Serbia. The results were obtained through monitoring defoliation of 34 tree species at 130 sample plots during the period from 2004 to 2018. This research aimed to determine whether the occurrence of defoliation and tree mortality were caused by drought. Defoliation was assessed in 5% steps according to the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) methodology. All the trees recorded as dead were singled out, and annual mortality rates were calculated. To determine changes in air temperature and precipitation regimes during the study period, we processed and analysed climatic data related to air temperature and precipitation throughout the year and in the growing season at 28 main weather stations in Serbia. Tree mortality patterns were established by classifying trees into three groups. The first group of trees exhibited a gradual increase in defoliation during the last few years of monitoring, with dying as the final outcome. The second group was characterised by sudden death of trees. The third group of trees reached a higher degree of defoliation immediately after the first monitoring year, and the trees died after several years. Tree mortality rates were compared between years using the Standardised Precipitation Evaporation Index (SPI) and the Standardised Precipitation Evapotranspiration Index (SPEI), the most common methods used to monitor drought. The most intensive forest decline was recorded during the period from 2013 to 2016, when the largest percentage of the total number of all trees died. According to the annual mortality rates calculated for the three observation periods (2004-2008, 2009-2013, and 2014-2018) the highest forest decline rate was recorded in the period from 2014 to 2018, with no statistically significant difference between broadleaved and coniferous tree species. As the sample of coniferous species was small, the number of sample plots should be increased in order to achieve better systematic forest condition monitoring in Serbia. The analysis of the relationship between defoliation and climatic parameters proved the correlation between them. It was noted that the forest decline in Serbia was preceded by an extremely dry period with high temperatures from 2011 to 2013, supporting the hypothesis that it was caused by drought. We therefore conclude that these unfavourable climatic conditions had serious and long-term consequences on forest ecosystems in Serbia.
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Affiliation(s)
- Goran Češljar
- Department of Spatial Regulation, GIS and Forest Policy, Institute of Forestry, 11030 Belgrade, Serbia;
| | - Filip Jovanović
- Department of Forest Establishment, Silviculture and Ecology, Institute of Forestry, 11030 Belgrade, Serbia; (F.J.); (S.E.); (T.Ć.-M.)
| | - Ljiljana Brašanac-Bosanac
- Department of Environmental Protection and Improvement, Institute of Forestry, 11030 Belgrade, Serbia; (L.B.-B.); (S.M.)
| | - Ilija Đorđević
- Department of Spatial Regulation, GIS and Forest Policy, Institute of Forestry, 11030 Belgrade, Serbia;
| | - Suzana Mitrović
- Department of Environmental Protection and Improvement, Institute of Forestry, 11030 Belgrade, Serbia; (L.B.-B.); (S.M.)
| | - Saša Eremija
- Department of Forest Establishment, Silviculture and Ecology, Institute of Forestry, 11030 Belgrade, Serbia; (F.J.); (S.E.); (T.Ć.-M.)
| | - Tatjana Ćirković-Mitrović
- Department of Forest Establishment, Silviculture and Ecology, Institute of Forestry, 11030 Belgrade, Serbia; (F.J.); (S.E.); (T.Ć.-M.)
| | - Aleksandar Lučić
- Department of Genetics, Plant Breeding, Seed and Nursery Production, Institute of Forestry, 11030 Belgrade, Serbia;
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22
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Significant Loss of Ecosystem Services by Environmental Changes in the Mediterranean Coastal Area. FORESTS 2022. [DOI: 10.3390/f13050689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mediterranean coastal areas are among the most threated forest ecosystems in the northern hemisphere due to concurrent biotic and abiotic stresses. These may affect plants functionality and, consequently, their capacity to provide ecosystem services. In this study, we integrated ground-level and satellite-level measurements to estimate the capacity of a 46.3 km2 Estate to sequestrate air pollutants from the atmosphere, transported to the study site from the city of Rome. By means of a multi-layer canopy model, we also evaluated forest capacity to provide regulatory ecosystem services. Due to a significant loss in forest cover, estimated by satellite data as −6.8% between 2014 and 2020, we found that the carbon sink capacity decreased by 34% during the considered period. Furthermore, pollutant deposition on tree crowns has reduced by 39%, 46% and 35% for PM, NO2 and O3, respectively. Our results highlight the importance of developing an integrated approach combining ground measurements, modelling and satellite data to link air quality and plant functionality as key elements to improve the effectiveness of estimate of ecosystem services.
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Variations in leaf water status and drought tolerance of dominant tree species growing in multi-aged tropical forests in Thailand. Sci Rep 2022; 12:6882. [PMID: 35477746 PMCID: PMC9044374 DOI: 10.1038/s41598-022-10988-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022] Open
Abstract
Large-scale abandoned agricultural areas in Southeast Asia resulted in patches of forests of multiple successions and characteristics, challenging the study of their responses to environmental changes, especially under climatic water stress. Here, we investigated seasonal variation in leaf water status and drought tolerance of dominant tree species in three multi-aged tropical forests, ranging from 5 to > 200 years old, with contrasting soil moisture in Thailand. Seasonal variation in leaf water status differed among the forests with trees in young and intermediate sites demonstrating larger differences between seasons than the old-growth forest. Although vulnerability to embolism curves revealed that trees in old-growth forest were potentially more sensitive to declining leaf water status than others, they were predicted to lose < 5% of their hydraulic capacity as opposed to 13% for the trees in the younger sites. Our results suggest that the responses to water stress of tree species in different forest ages greatly vary with a tendency of trees in younger sites to be more resilience than those in older sites. Such information would benefit the selection of tree species that could adapt well to specific environments, thus improving the strategies for managing forests of different ages under a warmer future.
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Challis A, Blackman C, Ahrens C, Medlyn B, Rymer P, Tissue D. Adaptive plasticity in plant traits increases time to hydraulic failure under drought in a foundation tree. TREE PHYSIOLOGY 2022; 42:708-721. [PMID: 34312674 DOI: 10.1093/treephys/tpab096] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
The viability of forest trees, in response to climate change-associated drought, will depend on their capacity to survive through genetic adaptation and phenotypic plasticity in drought tolerance traits. Genotypes with enhanced plasticity for drought tolerance (adaptive plasticity) will have a greater ability to persist and delay the onset of hydraulic failure. By examining populations from different climate-origins grown under contrasting soil water availability, we tested for genotype (G), environment (E) and genotype-by-environment (G × E) effects on traits that determine the time it takes for saplings to desiccate from stomatal closure to 88% loss of stem hydraulic conductance (time to hydraulic failure, THF). Specifically, we hypothesized that: (i) THF is dependent on a G × E interaction, with longer THF for warm, dry climate populations in response to chronic water deficit treatment compared with cool, wet populations, and (ii) hydraulic and allometric traits explain the observed patterns in THF. Corymbia calophylla saplings from two populations originating from contrasting climates (warm-dry or cool-wet) were grown under well-watered and chronic soil water deficit treatments in large containers. Hydraulic and allometric traits were measured and then saplings were dried-down to critical levels of drought stress to estimate THF. Significant plasticity was detected in the warm-dry population in response to water-deficit, with enhanced drought tolerance compared with the cool-wet population. Projected leaf area and total plant water storage showed treatment variation, and minimum conductance showed significant population differences driving longer THF in trees from warm-dry origins grown in water-limited conditions. Our findings contribute information on intraspecific variation in key drought traits, including hydraulic and allometric determinants of THF. It highlights the need to quantify adaptive capacity in populations of forest trees in climate change-type drought to improve predictions of forest die-back.
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Affiliation(s)
- Anthea Challis
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Chris Blackman
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
- School of Biological Sciences, University of Tasmania, Hobart, TAS 7001, Australia
| | - Collin Ahrens
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Belinda Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Paul Rymer
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - David Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
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25
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A New Method of Estimating Groundwater Evapotranspiration at Sub-Daily Scale Using Water Table Fluctuations. WATER 2022. [DOI: 10.3390/w14060876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Riparian ecosystems fundamentally depend on groundwater, and accurate estimations of groundwater evapotranspiration (ETG) are important for understanding ecosystem functionality and managing regional water resources. Over the past several decades, various methods have been proposed to estimate groundwater evapotranspiration based on water table fluctuations. However, the majority of methods cannot resolve sub-daily variations in ETG. In this study, we proposed a new hydraulic theory-based ETG estimation method at a sub-daily time scale. To evaluate its performance, we employed a variety of measurements (i.e., water table levels, latent heat flux and soil water contents) at a riparian forest (T. ramosissima) in Northwest China from 25 July to 10 October in 2017. The results indicated that the proposed method can successfully estimate ETG at both sub-daily (R2 = 0.75) and daily (R2 = 0.88) time scales, but the variations in the specific yield under different water table conditions should be carefully taken into account. In addition, we investigated the seasonal variations in water uptake source of the riparian plant, and found that it had strong plasticity in water usage during the study period. That is, it consumed approximately equal amounts of soil water and groundwater when soil moisture was available, and tended to consume more groundwater for survival as the soil moisture was depleted. To verify the seasonal patterns of the water uptake of the riparian forest, systematic isotope-based studies are needed in future study.
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26
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Behzad HM, Jiang Y, Arif M, Wu C, He Q, Zhao H, Lv T. Tunneling-induced groundwater depletion limits long-term growth dynamics of forest trees. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 811:152375. [PMID: 34914990 DOI: 10.1016/j.scitotenv.2021.152375] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 11/29/2021] [Accepted: 12/09/2021] [Indexed: 05/20/2023]
Abstract
Human interventions such as tunnel construction have caused groundwater depletion, which substantially affected the functions of forest tree species and their communities. However, the extent to which tunneling-induced groundwater depletion (TIGD) degrades their function levels at various spatial-temporal scales under varying climate conditions remains still unclear. Researchers used stand-scale dendrological records to track and extract the effects of TIGD associated with a single or series of tunneling events (three tunneling events during 1999-2001, 2006-2008, and 2010-2013) on short- and long-term growth levels of two dominant drought-tolerant tree species across (karst and non-karst) landscapes affected by tunnel construction and landscapes not subjected to tunnel construction in a mountainous forest ecosystem located in the southwest of China. The results showed that growth responses of both trees stand to TIGD, and the TIGD-linked water losses of other available water sources were negative and widespread across tunnel-affected landscapes, particularly in the karst landscapes known as delicate landscapes. Tree stands with faster (more vigorous) growth rates showed more significant adverse growth levels in response to either tunneling-induced or drought-induced water stresses. Also, they showed the highest recovered growth levels in response to favorable climatic conditions. Moreover, the growth level in the tunnel-affected forest never fully recovered during six years of very wet weather (2012-2018) after the construction of the final (third) tunnel in 2010-2013. Current research shows that tunnel construction has a cumulatively detrimental impact on the long-term survival of the forest. Even with the mediation of long-term very wet circumstances, it can substantially restrict the development dynamics of the forest compared to drought.
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Affiliation(s)
- Hamid M Behzad
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Yongjun Jiang
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China.
| | - Muhammad Arif
- Key Laboratory of Eco-Environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Chao Wu
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - QiuFang He
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Haijuan Zhao
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Tongru Lv
- Chongqing Key Laboratory of Karst Environment & School of Geographical Sciences, Southwest University, Chongqing 400715, China
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Changes in vegetation and soil properties across 12 years after afforestation in the hilly-gully region of the Loess Plateau. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2021.e01989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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28
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Gessler A, Bächli L, Rouholahnejad Freund E, Treydte K, Schaub M, Haeni M, Weiler M, Seeger S, Marshall J, Hug C, Zweifel R, Hagedorn F, Rigling A, Saurer M, Meusburger K. Drought reduces water uptake in beech from the drying topsoil, but no compensatory uptake occurs from deeper soil layers. THE NEW PHYTOLOGIST 2022; 233:194-206. [PMID: 34610146 PMCID: PMC9293437 DOI: 10.1111/nph.17767] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/26/2021] [Indexed: 06/02/2023]
Abstract
The intensity and frequency of droughts events are projected to increase in future with expected adverse effects for forests. Thus, information on the dynamics of tree water uptake from different soil layers during and after drought is crucial. We applied an in situ water isotopologue monitoring system to determine the oxygen isotope composition in soil and xylem water of European beech with a 2-h resolution together with measurements of soil water content, transpiration and tree water deficit. Using a Bayesian isotope mixing model, we inferred the relative and absolute contribution of water from four different soil layers to tree water use. Beech took up more than 50% of its water from the uppermost 5 cm soil layer at the beginning of the 2018 drought, but then reduced absolute water uptake from the drying topsoil by 84%. The trees were not able to quantitatively compensate for restricted topsoil water availability by additional uptake from deeper soil layers, which is related to the fine root depth distribution. Absolute water uptake from the topsoil was restored to pre-drought levels within 3 wk after rewetting. These uptake patterns help to explain both the drought sensitivity of beech and its high recovery potential after drought release.
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Affiliation(s)
- Arthur Gessler
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH Zurich8092ZurichSwitzerland
| | - Lukas Bächli
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | | | - Kerstin Treydte
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Marcus Schaub
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Matthias Haeni
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Markus Weiler
- Hydrology, Faculty of Environment and Natural ResourcesUniversity of Freiburg79098FreiburgGermany
| | - Stefan Seeger
- Hydrology, Faculty of Environment and Natural ResourcesUniversity of Freiburg79098FreiburgGermany
| | - John Marshall
- Department of Forest Ecology and ManagementSwedish University of Agricultural SciencesUmeå90283Sweden
| | - Christian Hug
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Roman Zweifel
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Frank Hagedorn
- Research Unit Forest Soils and BiogeochemistrySwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Andreas Rigling
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH Zurich8092ZurichSwitzerland
| | - Matthias Saurer
- Research Unit Forest DynamicsSwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
| | - Katrin Meusburger
- Research Unit Forest Soils and BiogeochemistrySwiss Federal Research Institute for Forest, Snow and Landscape Research WSL8903BirmensdorfSwitzerland
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Pivovaroff AL, McDowell NG, Rodrigues TB, Brodribb T, Cernusak LA, Choat B, Grossiord C, Ishida Y, Jardine KJ, Laurance S, Leff R, Li W, Liddell M, Mackay DS, Pacheco H, Peters J, de J Sampaio Filho I, Souza DC, Wang W, Zhang P, Chambers J. Stability of tropical forest tree carbon-water relations in a rainfall exclusion treatment through shifts in effective water uptake depth. GLOBAL CHANGE BIOLOGY 2021; 27:6454-6466. [PMID: 34469040 DOI: 10.1111/gcb.15869] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
Increasing severity and frequency of drought is predicted for large portions of the terrestrial biosphere, with major impacts already documented in wet tropical forests. Using a 4-year rainfall exclusion experiment in the Daintree Rainforest in northeast Australia, we examined canopy tree responses to reduced precipitation and soil water availability by quantifying seasonal changes in plant hydraulic and carbon traits for 11 tree species between control and drought treatments. Even with reduced soil volumetric water content in the upper 1 m of soil in the drought treatment, we found no significant difference between treatments for predawn and midday leaf water potential, photosynthesis, stomatal conductance, foliar stable carbon isotope composition, leaf mass per area, turgor loss point, xylem vessel anatomy, or leaf and stem nonstructural carbohydrates. While empirical measurements of aboveground traits revealed homeostatic maintenance of plant water status and traits in response to reduced soil moisture, modeled belowground dynamics revealed that trees in the drought treatment shifted the depth from which water was acquired to deeper soil layers. These findings reveal that belowground acclimation of tree water uptake depth may buffer tropical rainforests from more severe droughts that may arise in future with climate change.
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Affiliation(s)
- Alexandria L Pivovaroff
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Nate G McDowell
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Tayana Barrozo Rodrigues
- Forest Management Laboratory, National Institute of Amazonian Research, Manaus, Amazonas, Brazil
| | - Tim Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, Queensland, Australia
| | - Brendan Choat
- University of Western Sydney, Hawkesbury Institute for the Environment, Richmond, New South Wales, Australia
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, Switzerland
- Functional Plant Ecology, Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Lausanne, Switzerland
| | - Yoko Ishida
- College of Science and Engineering, James Cook University, Cairns, Queensland, Australia
| | - Kolby J Jardine
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Susan Laurance
- College of Science and Engineering, James Cook University, Cairns, Queensland, Australia
| | - Riley Leff
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Weibin Li
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Michael Liddell
- College of Science and Engineering, James Cook University, Cairns, Queensland, Australia
| | - D Scott Mackay
- Department of Geography and Department of Environment & Sustainability, University at Buffalo, Buffalo, New York, USA
| | - Heather Pacheco
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Jennifer Peters
- University of Western Sydney, Hawkesbury Institute for the Environment, Richmond, New South Wales, Australia
- Oak Ridge National Laboratory, Climate Change Science Institute & Environmental Science Division, Oak Ridge, Tennessee, USA
| | | | - Daisy C Souza
- Forest Management Laboratory, National Institute of Amazonian Research, Manaus, Amazonas, Brazil
| | - Wenzhi Wang
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Peipei Zhang
- Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Jeff Chambers
- Climate Sciences Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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30
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Disentangling the Effects of Tree and Soil Properties on the Water Uptake of a Waterlogging Tolerant Tree in the Yangtze River Delta, China. FORESTS 2021. [DOI: 10.3390/f12111547] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Waterlogging tolerant tree species exert a critical role in forest preservation and the associated water conservation in flood prone areas. Clarifying the patterns and drivers of water uptake by waterlogging tolerant trees is crucial for forest management in flood-prone areas, especially in the scenario of precipitation changes in the estuary delta. Here, we uploaded the values of δD and δ18O obtained from soil and xylem waters to a Bayesian mixed model (MixSIAR) to determine the water use pattern of Taxodium distichum, a waterlogging tolerant tree, following different magnitudes of rainfall events in three sites of the Yangtze River Delta, China. We further conducted variation partitioning analysis and a random forest model to discern the dominant factor driving plant water uptake. Our results indicated that T. distichum mainly absorbed soil water from shallow soil layers (0–40 cm, 43.63%–74.70%), while the percentage of water uptake from deep soil layers was lower in the Yangtze River Delta (60–100 cm, 13.43%–35.90%), whether in light, moderate, or heavy rainfall conditions. Furthermore, our results demonstrated that tree traits, such as fine root biomass, are dominantly driving plant water uptake. These findings imply that waterlogging tolerant tree species could increase the percentage of water uptake from shallow soils by changing their plant attributes, which would effectively improve the water conservation of forests in the estuary delta.
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31
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Liu C, Huang Y, Wu F, Liu W, Ning Y, Huang Z, Tang S, Liang Y. Plant adaptability in karst regions. JOURNAL OF PLANT RESEARCH 2021; 134:889-906. [PMID: 34258691 DOI: 10.1007/s10265-021-01330-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
Karst ecosystems are formed by dissolution of soluble rocks, usually with conspicuous landscape features, such as sharp peaks, steep slopes and deep valleys. The plants in karst regions develop special adaptability. Here, we reviewed the research progresses on plant adaptability in karst regions, including drought, high temperature and light, high-calcium stresses responses and the strategies of water utilization for plants, soil nutrients impact, human interference and geographical traits on karst plants. Drought, high temperature and light change their physiological and morphological structures to adapt to karst environments. High-calcium and soil nutrients can transfer surplus nutrients to special parts of plants to avoid damage of high nutrient concentration. Therefore, karst plants can make better use of limited water. Human interference also affects geographical distribution of karst plants and their growing environment. All of these aspects may be analyzed to provide guidance and suggestions for related research on plant adaptability mechanisms.
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Affiliation(s)
- Chunni Liu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China
| | - Yang Huang
- School of Mechanical and Electrical Engineering, Guilin University of Electronic Technology, Guilin, China
| | - Feng Wu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China
| | - Wenjing Liu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China
| | - Yiqiu Ning
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China
| | - Zhenrong Huang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China
| | - Shaoqing Tang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China
| | - Yu Liang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Life Science, Guangxi Normal University, Ministry of Education, Guilin, China.
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32
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Oak Competition Dominates Interspecific Interactions in Growth and Water-Use Efficiency in a Mixed Pine–Oak Mediterranean Forest. FORESTS 2021. [DOI: 10.3390/f12081093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In the Mediterranean, mixed forests of Aleppo pine and holm oak are widespread. Generally considered a transition stage in the succession towards climax oak communities, niche segregation may also contribute to the prevalence of these communities. So far, there is increasing evidence of hydrological niche segregation, with the two species showing complementary water use and seasonal growth patterns. However, it remains unknown whether interspecific interactions affect the response to climate and the mid-term (decadal) growth and water-use efficiency of pines and oaks in mixed stands. Here, we combined tree-ring chronologies, built on different competition classes within a mixed stand, with a spatially explicit assessment of individual growth and wood carbon isotope discrimination (∆13C), as a proxy of intrinsic water-use efficiency, and compared these results with previously reported water uptake patterns. We found that competition with pines modulated the climate response of oaks, whereas pine climate response was insensitive to competition. On the other hand, pine density affected only pine growth, whereas oak competition affected both species. We conclude that the presence of pines had negligible or even positive effects on the oaks, but competition with neighbor oaks limited their ability to recover after drought. Conversely, pines experienced greater drought stress under competition, with both oaks and pines.
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Croy JR, Pratt JD, Sheng D, Mooney KA. Climatic displacement exacerbates the negative impact of drought on plant performance and associated arthropod abundance. Ecology 2021; 102:e03462. [PMID: 34236699 DOI: 10.1002/ecy.3462] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/27/2021] [Accepted: 05/14/2021] [Indexed: 12/14/2022]
Abstract
Climate change is acting on species and modifying communities and ecosystems through changes not only with respect to mean abiotic conditions, but also through increases in the frequency and severity of extreme events. Changes in mean aridity associated with climate change can generate ecotype by environment mismatch (i.e., climatic displacement). At the same time, variability around these shifting means is predicted to increase, resulting in more extreme droughts. We characterized the effects of two axes of climate change, climatic displacement and drought, on the shrub Artemisia californica and its arthropods. We established common gardens of plants sourced along an aridity gradient (3.5-fold variation in mean annual precipitation) in an arid region of the species distribution, thus generating a gradient of climatic displacement (sustained increase in aridity) as predicted with climate change. We surveyed plants and arthropods over eight years where precipitation varied sixfold, including both extreme drought and relatively mesic conditions. These two axes of climate change interacted to influence plant performance, such that climatically displaced populations grew slowly regardless of drought and suffered substantial mortality during drought years. Conversely, local populations grew quickly, increased growth during wet years, and had low mortality regardless of drought. Effects on plant annual arthropod yield were negative and additive, with drought effects exceeding that of climatic displacement by 24%. However, for plant lifetime arthropod yield, incorporating effects on both plant growth and survival, climatic displacement exacerbated the negative effects of drought. Collectively these results demonstrate how climatic displacement (through increasing aridity stress) strengthens the negative effects of drought on plants and, indirectly, on arthropods, suggesting the possibility of climate-mediated trophic collapse.
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Affiliation(s)
- Jordan R Croy
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, 92697, USA
| | - Jessica D Pratt
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, 92697, USA
| | - Daniel Sheng
- Forestry Division of the County of Los Angeles Fire Department, Los Angeles, California, 91773, USA
| | - Kailen A Mooney
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, 92697, USA
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Lorente B, Zugasti I, Sánchez-Blanco MJ, Nicolás E, Ortuño MF. Effect of Pisolithus tinctorious on Physiological and Hormonal Traits in Cistus Plants to Water Deficit: Relationships among Water Status, Photosynthetic Activity and Plant Quality. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10050976. [PMID: 34068420 PMCID: PMC8153628 DOI: 10.3390/plants10050976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 04/25/2021] [Accepted: 05/10/2021] [Indexed: 06/12/2023]
Abstract
Cistus species can form ectomycorrhizae and arbuscular mycorrhizal fungus that can bring benefits when plants are under water stress conditions. However, the application of some ectomycorrhizae on the water uptake under drought through physiological traits and hormonal regulation is less known. The experiment was performed during three months in a growth chamber with Cistus albidus plants in which the combined effect of the ectomycorrhiza Pisolithus tinctorious inoculation and two irrigation treatments (control and water-stressed plants) were applied. Irrigation absence caused significant decrease in aerial growth and tended to decrease soil water potential at the root surface, leading to a decrease in leaf water potential. Under these conditions, the abscisic acid and salicylic acid content increased while the precursor of ethylene decreased. Although the mycorrhization percentages were not high, the inoculation of P. tinctorious improved the water status and slightly cushioned the rise in leaf temperature of water-stressed plants. The ectomycorrhiza decreased the scopoletin values in leaves of plants subjected to deficit irrigation, indicating that inoculated plants had been able to synthesize defense mechanisms. Therefore, Pisolithus tinctorious alleviated some of the harmful effects of water scarcity in Cistus plants, being its use a sustainable option in gardening or restoration projects.
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35
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Global Change and Forest Disturbances in the Mediterranean Basin: Breakthroughs, Knowledge Gaps, and Recommendations. FORESTS 2021. [DOI: 10.3390/f12050603] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Forest ecosystems in the Mediterranean Basin are mostly situated in the north of the Basin (mesic). In the most southern and dry areas, the forest can only exist where topography and/or altitude favor a sufficient availability of water to sustain forest biomass. We have conducted a thorough review of recent literature (2000–2021) that clearly indicates large direct and indirect impacts of increasing drought conditions on the forests of the Mediterranean Basin, their changes in surface and distribution areas, and the main impacts they have suffered. We have focused on the main trends that emerge from the current literature and have highlighted the main threatens and management solution for the maintenance of these forests. The results clearly indicate large direct and indirect impacts of increasing drought conditions on the forests of the Mediterranean Basin. These increasing drought conditions together with over-exploitation, pest expansion, fire and soil degradation, are synergistically driving to forest regression and dieback in several areas of this Mediterranean Basin. These environmental changes have triggered responses in tree morphology, physiology, growth, reproduction, and mortality. We identified at least seven causes of the changes in the last three decades that have led to the current situation and that can provide clues for projecting the future of these forests: (i) The direct effect of increased aridity due to more frequent and prolonged droughts, which has driven Mediterranean forest communities to the limit of their capacity to respond to drought and escape to wetter sites, (ii) the indirect effects of drought, mainly by the spread of pests and fires, (iii) the direct and indirect effects of anthropogenic activity associated with general environmental degradation, including soil degradation and the impacts of fire, species invasion and pollution, (iv) human pressure and intense management of water resources, (v) agricultural land abandonment in the northern Mediterranean Basin without adequate management of new forests, (vi) very high pressure on forested areas of northern Africa coupled with the demographic enhancement, the expansion of crops and higher livestock pressure, and the more intense and overexploitation of water resources uses on the remaining forested areas, and (vii) scarcity and inequality of human management and policies, depending on the national and/or regional governments and agencies, being unable to counteract the previous changes. We identified appropriate measures of management intervention, using the most adequate techniques and processes to counteract these impacts and thus to conserve the health, service capacity, and biodiversity of Mediterranean forests. Future policies should, moreover, promote research to improve our knowledge of the mechanisms of, and the effects on, nutrient and carbon plant-soil status concurrent with the impacts of aridity and leaching due to the effects of current changes. Finally, we acknowledge the difficulty to obtain an accurate quantification of the impacts of increasing aridity rise that warrants an urgent investment in more focused research to further develop future tools in order to counteract the negative effects of climate change on Mediterranean forests.
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Querejeta JI, Ren W, Prieto I. Vertical decoupling of soil nutrients and water under climate warming reduces plant cumulative nutrient uptake, water-use efficiency and productivity. THE NEW PHYTOLOGIST 2021; 230:1378-1393. [PMID: 33550582 DOI: 10.1111/nph.17258] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/01/2021] [Indexed: 05/21/2023]
Abstract
Warming-induced desiccation of the fertile topsoil layer could lead to decreased nutrient diffusion, mobility, mineralization and uptake by roots. Increased vertical decoupling between nutrients in topsoil and water availability in subsoil/bedrock layers under warming could thereby reduce cumulative nutrient uptake over the growing season. We used a Mediterranean semiarid shrubland as model system to assess the impacts of warming-induced topsoil desiccation on plant water- and nutrient-use patterns. A 6 yr manipulative field experiment examined the effects of warming (2.5°C), rainfall reduction (30%) and their combination on soil resource utilization by Helianthemum squamatum shrubs. A drier fertile topsoil ('growth pool') under warming led to greater proportional utilization of water from deeper, wetter, but less fertile subsoil/bedrock layers ('maintenance pool') by plants. This was linked to decreased cumulative nutrient uptake, increased nonstomatal (nutritional) limitation of photosynthesis and reduced water-use efficiency, above-ground biomass growth and drought survival. Whereas a shift to greater utilization of water stored in deep subsoil/bedrock may buffer the negative impact of warming-induced topsoil desiccation on transpiration, this plastic response cannot compensate for the associated reduction in cumulative nutrient uptake and carbon assimilation, which may compromise the capacity of plants to adjust to a warmer and drier climate.
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Affiliation(s)
- José Ignacio Querejeta
- Departamento de Conservación de Suelos y Agua, Centro de Edafología y Biología Aplicada del Segura - Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Murcia, 30100, Spain
| | - Wei Ren
- Departamento de Conservación de Suelos y Agua, Centro de Edafología y Biología Aplicada del Segura - Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Murcia, 30100, Spain
- Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing, 400715, China
| | - Iván Prieto
- Departamento de Conservación de Suelos y Agua, Centro de Edafología y Biología Aplicada del Segura - Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Murcia, 30100, Spain
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37
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Tracing plant–environment interactions from organismal to planetary scales using stable isotopes: a mini review. Emerg Top Life Sci 2021; 5:301-316. [DOI: 10.1042/etls20200277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 01/09/2023]
Abstract
Natural isotope variation forms a mosaic of isotopically distinct pools across the biosphere and flows between pools integrate plant ecology with global biogeochemical cycling. Carbon, nitrogen, and water isotopic ratios (among others) can be measured in plant tissues, at root and foliar interfaces, and in adjacent atmospheric, water, and soil environments. Natural abundance isotopes provide ecological insight to complement and enhance biogeochemical research, such as understanding the physiological conditions during photosynthetic assimilation (e.g. water stress) or the contribution of unusual plant water or nutrient sources (e.g. fog, foliar deposition). While foundational concepts and methods have endured through four decades of research, technological improvements that enable measurement at fine spatiotemporal scales, of multiple isotopes, and of isotopomers, are advancing the field of stable isotope ecology. For example, isotope studies now benefit from the maturation of field-portable infrared spectroscopy, which allows the exploration of plant–environment sensitivity at physiological timescales. Isotope ecology is also benefiting from, and contributing to, new understanding of the plant–soil–atmosphere system, such as improving the representation of soil carbon pools and turnover in land surface models. At larger Earth-system scales, a maturing global coverage of isotope data and new data from site networks offer exciting synthesis opportunities to merge the insights of single-or multi-isotope analysis with ecosystem and remote sensing data in a data-driven modeling framework, to create geospatial isotope products essential for studies of global environmental change.
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38
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Ding Y, Nie Y, Chen H, Wang K, Querejeta JI. Water uptake depth is coordinated with leaf water potential, water-use efficiency and drought vulnerability in karst vegetation. THE NEW PHYTOLOGIST 2021; 229:1339-1353. [PMID: 32989748 DOI: 10.1111/nph.16971] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 09/10/2020] [Accepted: 09/14/2020] [Indexed: 06/11/2023]
Abstract
Root access to bedrock water storage or groundwater is an important trait allowing plant survival in seasonally dry environments. However, the degree of coordination between water uptake depth, leaf-level water-use efficiency (WUEi) and water potential in drought-prone plant communities is not well understood. We conducted a 135-d rainfall exclusion experiment in a subtropical karst ecosystem with thin skeletal soils to evaluate the responses of 11 co-occurring woody species of contrasting life forms and leaf habits to a severe drought during the wet growing season. Marked differences in xylem water isotopic composition during drought revealed distinct ecohydrological niche separation among species. The contrasting behaviour of leaf water potential in coexisting species during drought was largely explained by differences in root access to deeper, temporally stable water sources. Smaller-diameter species with shallower water uptake, more negative water potentials and lower WUEi showed extensive drought-induced canopy defoliation and/or mortality. By contrast, larger-diameter species with deeper water uptake, higher leaf-level WUEi and more isohydric behaviour survived drought with only moderate canopy defoliation. Severe water limitation imposes strong environmental filtering and/or selective pressures resulting in tight coordination between tree diameter, water uptake depth, iso/anisohydric behaviour, WUEi and drought vulnerability in karst plant communities.
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Affiliation(s)
- Yali Ding
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
- Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang, Guangxi, 547100, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yunpeng Nie
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
- Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang, Guangxi, 547100, China
| | - Hongsong Chen
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
- Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang, Guangxi, 547100, China
| | - Kelin Wang
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
- Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang, Guangxi, 547100, China
| | - José I Querejeta
- Soil and Water Conservation Department, Centro de Edafología y Biología Aplicada del Segura-Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Campus Universitario de Espinardo, Murcia, E30100, Spain
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39
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Barbeta A, Gimeno TE, Clavé L, Fréjaville B, Jones SP, Delvigne C, Wingate L, Ogée J. An explanation for the isotopic offset between soil and stem water in a temperate tree species. THE NEW PHYTOLOGIST 2020; 227:766-779. [PMID: 32239512 DOI: 10.1111/nph.16564] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 03/14/2020] [Indexed: 06/11/2023]
Abstract
A growing number of field studies report isotopic offsets between stem water and its potential sources that prevent the unambiguous identification of plant water origin using water isotopes. We explored the causes of this isotopic offset by conducting a controlled experiment on the temperate tree species Fagus sylvatica. We measured δ2 H and δ18 O of soil and stem water from potted saplings growing on three soil substrates and subjected to two watering regimes. Regardless of substrate, soil and stem water δ2 H were similar only near permanent wilting point. Under moister conditions, stem water δ2 H was 11 ± 3‰ more negative than soil water δ2 H, coherent with field studies. Under drier conditions, stem water δ2 H became progressively more enriched than soil water δ2 H. Although stem water δ18 O broadly reflected that of soil water, soil-stem δ2 H and δ18 O differences were correlated (r = 0.76) and increased with transpiration rates indicated by proxies. Soil-stem isotopic offsets are more likely to be caused by water isotope heterogeneities within the soil pore and stem tissues, which would be masked under drier conditions as a result of evaporative enrichment, than by fractionation under root water uptake. Our results challenge our current understanding of isotopic signals in the soil-plant continuum.
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Affiliation(s)
- Adrià Barbeta
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
- BEECA, Department of Evolutionary Biology, Ecology and Environmental Sciences, Universitat de Barcelona, Barcelona, Catalonia, Spain
| | - Teresa E Gimeno
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
- Basque Centre for Climate Change, 48940, Leioa, Spain
- IKERBASQUE, Basque Foundation for Science, 48008, Bilbao, Spain
| | - Laura Clavé
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
| | | | - Sam P Jones
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
- Instituto Nacional de Pesquisas da Amazônia, Manaus, CEP 69060-001, Brazil
| | - Camille Delvigne
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
- Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Lisa Wingate
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
| | - Jérôme Ogée
- INRAE, UMR1391 ISPA, 33140, Villenave d'Ornon, France
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40
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Retrospective Analysis of Tree Decline Based on Intrinsic Water-Use Efficiency in Semi-Arid Areas of North China. ATMOSPHERE 2020. [DOI: 10.3390/atmos11060577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Long-term tree growth is significantly affected by climate change, which have become a global concern. Tree-ring width and isotopic information can show how trees respond to climate change on a long-term scale and reveal some phenomena of tree decline or death. In this study, we used isotopic techniques and investigated annual changes in carbon isotope composition and tree-ring width of Populus simonii Carr. in Zhangbei, as well as trends in tree-ring carbon discrimination (Δ13C) and iWUE in normal, mildly declining and severely declining trees, in order to make a retrospective analysis and further understand the process of tree decline. We found that there were significant differences (p < 0.01 **) in δ13C, Δ13C, ci and iWUE at different decline stages, meaning that the δ13C and iWUE could be new indicators of tree health. The iWUE of all groups increased significantly, while the growth rate of declined P. simonii was much higher than that of normal growth P. simonii. According to the analysis, there may be a threshold of iWUE for healthy trees, which once the threshold value is exceeded, it indicates that trees are resistant to adversity and their growth is under stress. Similarly, the changing trend of BAI supports our conclusion with its changes showed that tree growth became slower and slower as degradation progressed. iWUE inferred from tree-ring stable carbon isotope composition is a strong modulator of adaptation capacity in response to environmental stressors under climate change. Elevated annual temperatures and increased groundwater depth are all contributing to the decline of P. simonii in north China.
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Ripullone F, Camarero JJ, Colangelo M, Voltas J. Variation in the access to deep soil water pools explains tree-to-tree differences in drought-triggered dieback of Mediterranean oaks. TREE PHYSIOLOGY 2020; 40:591-604. [PMID: 32159804 DOI: 10.1093/treephys/tpaa026] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/01/2020] [Indexed: 06/10/2023]
Abstract
Individual differences in the access to deep soil water pools may explain the differential damage among coexisting, conspecific trees as a consequence of drought-induced dieback. We addressed this issue by comparing the responses to a severe drought of three Mediterranean oak species with different drought tolerance, Quercus pubescens L. and Quercus frainetto Ten., mainly thriving at xeric and mesic sites, respectively, and Quercus cerris L., which dominates at intermediate sites. For each species, we compared coexisting declining (D) and non-declining (ND) trees. The stable isotope composition (δ2H, δ18O) of xylem and soil water was used to infer a differential use of soil water sources. We also measured tree size and radial growth to quantify the long-term divergence of wood production between D and ND trees and non-structural carbohydrates (NSCs) in sapwood to evaluate if D trees presented lower NSC values. The ND trees had access to deeper soil water than D trees except in Q. frainetto, as indicated by significantly more depleted xylem water values. However, a strong δ2H offset between soil and xylem water isotopes observed in peak summer could suggest that both tree types were not physiologically active under extreme drought conditions. Alternative processes causing deuterium fractionation, however, could not be ruled out. Tree height and recent (last 15-25 years) growth rates in all species studied were lower in D than in ND trees by 22 and 44%, respectively. Lastly, there was not a consistent pattern of NSC sapwood concentration; in Q. pubescens, it was higher in ND trees while in Q. frainetto, the D trees were the ones exhibiting the higher NSC concentration. We conclude that the vulnerability to drought among conspecific Mediterranean oaks depends on the differential access to deep soil water pools, which may be related to differences in rooting depth, tree size and growth rate.
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Affiliation(s)
- Francesco Ripullone
- School of Agricultural, Forest, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano 10, Potenza I-85100, Italy
| | - J Julio Camarero
- Instituto Pirenaico de Ecología (IPE-CSIC), Avda Montañana 1005, Zaragoza E-50059, Spain
| | - Michele Colangelo
- School of Agricultural, Forest, Food and Environmental Sciences, University of Basilicata, Viale dell'Ateneo Lucano 10, Potenza I-85100, Italy
- Instituto Pirenaico de Ecología (IPE-CSIC), Avda Montañana 1005, Zaragoza E-50059, Spain
| | - Jordi Voltas
- Joint Research Unit CTFC-AGROTECNIO, Av. Alcalde Rovira Roure 191, Lleida 25198, Spain
- Department of Crop and Forest Sciences, University of Lleida, Av. Alcalde Rovira Roure 191, Lleida 25198, Spain
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Carrière SD, Martin-StPaul NK, Cakpo CB, Patris N, Gillon M, Chalikakis K, Doussan C, Olioso A, Babic M, Jouineau A, Simioni G, Davi H. Tree xylem water isotope analysis by Isotope Ratio Mass Spectrometry and laser spectrometry: A dataset to explore tree response to drought. Data Brief 2020; 29:105349. [PMID: 32181309 PMCID: PMC7066053 DOI: 10.1016/j.dib.2020.105349] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 02/13/2020] [Accepted: 02/21/2020] [Indexed: 11/30/2022] Open
Abstract
Water isotopes from plant xylem and surrounding environment are increasingly used in eco-hydrological studies. Carrière et al. [1] analyzed a dataset of water isotopes in (i) the xylem of three different tree species, (ii) the surrounding soil and drainage water and (iii) the underlying karst groundwater, to understand tree water uptake during drought in two different Mediterranean forests on karst setting. The xylem and soil water were extracted by cryogenic distillation. The full dataset was obtained with Isotope Ratio Mass Spectrometry (IRMS) and Isotope Ratio Infrared Spectrometer (IRIS), and included 219 measurements of δ2H and δ18O. Prompted by unexpected isotopic data characterized by a very negative deuterium excess, a subsample of 46 xylem samples and 9 soil water samples were double checked with both analytical techniques. IRMS and IRIS analyses yielded similar data. Therefore, the results reveal that laser spectrometry allows an accurate estimation of xylem and soil water isotopes. The dataset highlights a strong 2H depletion in xylem water for all species. Deuterium does not seem adequate to interpret ecological processes in this dataset given the strong fractionation.
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Affiliation(s)
- Simon Damien Carrière
- INRAE, UMR 1114 EMMAH, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
| | - Nicolas K Martin-StPaul
- INRAE, URFM, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
| | - Coffi Belmys Cakpo
- INRAE, PSH, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Nicolas Patris
- Hydrosciences Montpellier, IRD, CNRS, Université de Montpellier, Montpellier, France
| | - Marina Gillon
- Avignon Université, UMR 1114 EMMAH, 301 Rue Baruch de Spinoza, BP 21239, 84911, Avignon Cedex 9, France
| | - Konstantinos Chalikakis
- Avignon Université, UMR 1114 EMMAH, 301 Rue Baruch de Spinoza, BP 21239, 84911, Avignon Cedex 9, France
| | - Claude Doussan
- INRAE, UMR 1114 EMMAH, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
| | - Albert Olioso
- INRAE, UMR 1114 EMMAH, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
| | - Milanka Babic
- Avignon Université, UMR 1114 EMMAH, 301 Rue Baruch de Spinoza, BP 21239, 84911, Avignon Cedex 9, France
| | - Arnaud Jouineau
- INRAE, URFM, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
| | - Guillaume Simioni
- INRAE, URFM, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
| | - Hendrik Davi
- INRAE, URFM, Domaine Saint Paul, INRAE Centre de Recherche PACA, 228 Route de L'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, 84914, Avignon Cedex 9, France
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Väänänen PJ, Osem Y, Cohen S, Grünzweig JM. Differential drought resistance strategies of co-existing woodland species enduring the long rainless Eastern Mediterranean summer. TREE PHYSIOLOGY 2020; 40:305-320. [PMID: 31860712 DOI: 10.1093/treephys/tpz130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/28/2019] [Accepted: 09/17/2019] [Indexed: 06/10/2023]
Abstract
In anticipation of a drier climate and to project future changes in forest dynamics, it is imperative to understand species-specific differences in drought resistance. The objectives of this study were to form a comprehensive understanding of the drought resistance strategies adopted by Eastern Mediterranean woodland species, and to elaborate specific ecophysiological traits that can explain the observed variation in survival among these species. We examined leaf water potential (𝛹), gas exchange and stem hydraulics during 2-3 years in mature individuals of the key woody species Phillyrea latifolia L., Pistacia lentiscus L. and Quercus calliprinos Webb that co-exist in a dry woodland experiencing ~ 6 rainless summer months. As compared with the other two similarly functioning species, Phillyrea displayed considerably lower 𝛹 (minimum 𝛹 of -8.7 MPa in Phillyrea vs -4.2 MPa in Pistacia and Quercus), lower 𝛹 at stomatal closure and lower leaf turgor loss point (𝛹TLP ), but reduced hydraulic vulnerability and wider safety margins. Notably, Phillyrea allowed 𝛹 to drop below 𝛹TLP under severe drought, whereas the other two species maintained positive turgor. These results indicate that Phillyrea adopted a more anisohydric drought resistance strategy, while Pistacia and Quercus exhibited a more isohydric strategy and probably relied on deeper water reserves. Unlike the two relatively isohydric species, Phillyrea reached complete stomatal closure at the end of the dry summer. Despite assessing a large number of physiological traits, none of them could be directly related to tree mortality. Higher mortality was observed for Quercus than for the other two species, which may result from higher water consumption due to its 2.5-10 times larger crown volume. The observed patterns suggest that similar levels of drought resistance in terms of survival can be achieved via different drought resistance strategies. Conversely, similar resistance strategies in terms of isohydricity can lead to different levels of vulnerability to extreme drought.
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Affiliation(s)
- Päivi J Väänänen
- Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel
- Department of Natural Resources, Agricultural Research Organization, Volcani Center, Bet-Dagan 50250, Israel
| | - Yagil Osem
- Department of Natural Resources, Agricultural Research Organization, Volcani Center, Bet-Dagan 50250, Israel
| | - Shabtai Cohen
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Bet-Dagan 50250, Israel
| | - José M Grünzweig
- Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel
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Ollivier C, Mazzilli N, Olioso A, Chalikakis K, Carrière SD, Danquigny C, Emblanch C. Karst recharge-discharge semi distributed model to assess spatial variability of flows. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 703:134368. [PMID: 31731168 DOI: 10.1016/j.scitotenv.2019.134368] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/03/2019] [Accepted: 09/07/2019] [Indexed: 06/10/2023]
Abstract
Aquifer recharge assessment is a key factor for sustainable groundwater resource management. Although main factors of the spatial and temporal variability of recharge are known, taking them into account in a distributed or semi-distributed model is still a challenging task. This difficulty is increased in karst environments. Indeed, recharge of karst aquifers also depends on the organization of the karst network, which is both highly heterogeneous and difficult to characterize. We developed a reservoir model to simulate the spatial and temporal variability of recharge on karst watersheds. Special attention was paid to the link between model parameters and measurable or qualitative environmental factors of recharge. The spatial variability of soil reservoir capacity was estimated by multifactorial modelling (neural network). Intrinsic vulnerability indices were used to constrain the partitioning between slow and fast flows within the karst aquifer. Comparison of simulated and measured discharge at the outlet was used to calibrate and assess recharge model. The karst hydrosystem of the Fontaine de Vaucluse is renowned for its significant heterogeneity and anisotropy, which has so far limited the application of 2D or 3D modelling. The model developed was successfully applied to this system. Our results showed that the annual recharge is very heterogeneous on the test site. Spatialization of recharge improves discharge modelling as evidenced by increased KGE (from 0.8 to 0.9) and more realistic flows during drought periods. It is therefore essential to spatialize recharge in karst hydrogeological modelling to improve predictive capacity and better understand functioning of the whole hydrosystem.
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Affiliation(s)
- Chloé Ollivier
- Avignon Université, UMR EMMAH, 301 rue Baruch de Spinoza, 84916 Avignon, France.
| | - Naomi Mazzilli
- Avignon Université, UMR EMMAH, 301 rue Baruch de Spinoza, 84916 Avignon, France
| | - Albert Olioso
- INRA, UMR EMMAH, Domaine St-Paul, 84914 Avignon, France
| | | | | | - Charles Danquigny
- Avignon Université, UMR EMMAH, 301 rue Baruch de Spinoza, 84916 Avignon, France
| | - Christophe Emblanch
- Avignon Université, UMR EMMAH, 301 rue Baruch de Spinoza, 84916 Avignon, France
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Carrière SD, Martin-StPaul NK, Cakpo CB, Patris N, Gillon M, Chalikakis K, Doussan C, Olioso A, Babic M, Jouineau A, Simioni G, Davi H. The role of deep vadose zone water in tree transpiration during drought periods in karst settings - Insights from isotopic tracing and leaf water potential. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 699:134332. [PMID: 31629315 DOI: 10.1016/j.scitotenv.2019.134332] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/04/2019] [Accepted: 09/05/2019] [Indexed: 06/10/2023]
Abstract
Karst environments are unusual because their dry, stony and shallow soils seem to be unfavorable to vegetation, and yet they are often covered with forests. How can trees survive in these environments? Where do they find the water that allows them to survive? This study uses midday and predawn water potentials and xylem water isotopes of branches to assess tree water status and the origin of transpired water. Monitoring was conducted during the summers of 2014 and 2015 in two dissimilar plots of Mediterranean forest located in karst environments. The results show that the three monitored tree species (Abies alba Mill, Fagus sylvatica L, and Quercus ilex L.) use deep water resources present in the karst vadose zone (unsaturated zone) more intensively during drier years. Quercus ilex, a species well- adapted to water stress, which grows at the drier site, uses the deep water resource very early in the summer season. Conversely, the two other species exploit the deep water resource only during severe drought. These results open up new perspectives to a better understanding of ecohydrological equilibrium and to improved water balance modeling in karst forest settings.
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Affiliation(s)
- Simon Damien Carrière
- INRA, UMR 1114 EMMAH, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France.
| | - Nicolas K Martin-StPaul
- INRA, URFM, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Coffi Belmys Cakpo
- INRA, PSH, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Nicolas Patris
- IRD, Hydroscience Montpellier, 300 Avenue du Professeur Emile Jeanbrau, 34090 Montpellier, France
| | - Marina Gillon
- UAPV, UMR 1114 EMMAH, 301 rue Baruch de Spinoza, BP 21239 84911 Avignon Cedex 9, France
| | | | - Claude Doussan
- INRA, UMR 1114 EMMAH, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Albert Olioso
- INRA, UMR 1114 EMMAH, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Milanka Babic
- UAPV, UMR 1114 EMMAH, 301 rue Baruch de Spinoza, BP 21239 84911 Avignon Cedex 9, France
| | - Arnaud Jouineau
- INRA, URFM, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Guillaume Simioni
- INRA, URFM, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Hendrik Davi
- INRA, URFM, Domaine Saint Paul, INRA Centre de recherche PACA, 228 route de l'Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
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Mackay DS, Savoy PR, Grossiord C, Tai X, Pleban JR, Wang DR, McDowell NG, Adams HD, Sperry JS. Conifers depend on established roots during drought: results from a coupled model of carbon allocation and hydraulics. THE NEW PHYTOLOGIST 2020; 225:679-692. [PMID: 31276231 DOI: 10.1111/nph.16043] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/01/2019] [Indexed: 06/09/2023]
Abstract
Trees may survive prolonged droughts by shifting water uptake to reliable water sources, but it is unknown if the dominant mechanism involves activating existing roots or growing new roots during drought, or some combination of the two. To gain mechanistic insights on this unknown, a dynamic root-hydraulic modeling framework was developed that set up a feedback between hydraulic controls over carbon allocation and the role of root growth on soil-plant hydraulics. The new model was tested using a 5 yr drought/heat field experiment on an established piñon-juniper stand with root access to bedrock groundwater. Owing to the high carbon cost per unit root area, modeled trees initialized without adequate bedrock groundwater access experienced potentially lethal declines in water potential, while all of the experimental trees maintained nonlethal water potentials. Simulated trees were unable to grow roots rapidly enough to mediate the hydraulic stress, particularly during warm droughts. Alternatively, modeled trees initiated with root access to bedrock groundwater matched the hydraulics of the experimental trees by increasing their water uptake from bedrock groundwater when soil layers dried out. Therefore, the modeling framework identified a critical mechanism for drought response that required trees to shift water uptake among existing roots rather than growing new roots.
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Affiliation(s)
- D Scott Mackay
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Philip R Savoy
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Charlotte Grossiord
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland
| | - Xiaonan Tai
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Jonathan R Pleban
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Diane R Wang
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | | | - Henry D Adams
- Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, Stillwater, OK, 74078, USA
| | - John S Sperry
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
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Gori A, Tattini M, Centritto M, Ferrini F, Marino G, Mori J, Guidi L, Brunetti C. Seasonal and daily variations in primary and secondary metabolism of three maquis shrubs unveil different adaptive responses to Mediterranean climate. CONSERVATION PHYSIOLOGY 2019; 7:coz070. [PMID: 32467757 PMCID: PMC7245392 DOI: 10.1093/conphys/coz070] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 08/08/2019] [Accepted: 08/29/2019] [Indexed: 05/20/2023]
Abstract
Maquis species play a central role in the maintenance of coastal ecosystems thanks to anatomical, physiological and biochemical features evolved to cope with severe stress conditions. Because the seasonal and daily dynamics of physiological and biochemical traits of maquis species are not fully addressed, we performed a field study on three coexisting Mediterranean shrubs (Pistacia lentiscus L. and Phillyrea latifolia L., evergreen schlerophylls, and Cistus incanus L., semi-deciduous) aiming at detecting the main adaptive differences, on a seasonal and daily basis, in primary and secondary metabolism along with the principal climatic determinants. These species differed in their physiological and biochemical responses especially on a seasonal level. In P. latifolia, a great investment in antioxidant phenylpropanoids contributed to maintain high photosynthetic rates throughout the whole growing season. In C. incanus, high carotenoid content associated with chlorophyll (Chl) regulation alleviated oxidative damage during the hot and dry summers and help recover photosynthesis in autumn. In P. lentiscus, high abscisic acid levels allowed a strict control of stomata, while fine Chla/Chlb regulation concurred to avoid photoinhibition in summer. Temperature resulted the most important climatic factor controlling the physiological and biochemical status of these coexisting shrubs and, thus, in determining plant performances in this Mediterranean coastal habitat.
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Affiliation(s)
- Antonella Gori
- Department of Agriculture, Food, Environment and Forestry, University of Florence, viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy
| | - Massimiliano Tattini
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
| | - Mauro Centritto
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
| | - Francesco Ferrini
- Department of Agriculture, Food, Environment and Forestry, University of Florence, viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy
| | - Giovanni Marino
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
| | - Jacopo Mori
- Department of Agriculture, Food, Environment and Forestry, University of Florence, viale delle Idee 30, 50019, Sesto Fiorentino, Florence, Italy
| | - Lucia Guidi
- Department of Agriculture, Food and Environment, University of Pisa, Lungarno Pacinotti 43, 56126, Pisa, Italy
| | - Cecilia Brunetti
- Institute for Sustainable Plant Protection, National Research Council of Italy, via Madonna del Piano 10, 50019, Sesto Fiorentino, Florence, Italy
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Parente J, Amraoui M, Menezes I, Pereira MG. Drought in Portugal: Current regime, comparison of indices and impacts on extreme wildfires. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 685:150-173. [PMID: 31174114 DOI: 10.1016/j.scitotenv.2019.05.298] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 05/19/2019] [Accepted: 05/20/2019] [Indexed: 06/09/2023]
Abstract
In Portugal, drought characterizes the climatic variability, contributes to the increase of fire risk and its duration and intensity are expected to increase in future climate. Surprisingly, the quantitative and objective analysis to characterize the drought regime in current climate conditions as well as its influence on the occurrence of large wildfires (LW) has never been done for Portugal, which are the main objectives of this study. We assessed drought regime for recent past climate conditions (1981-2017), using four different drought indices, namely SPI, SPEI, RDI and VCI, and assessed the influence of drought in LW occurrence. Results include the characterization of drought number, duration, severity, intensity, extension, intra- and inter-annual variability for different classes of severity and the space-time distribution of LW in drought periods and affected area. Our main findings include 67% of the study period were drought months; regions with higher drought duration and severity assessed with SPI and SPEI for general drought conditions evolves from north to south with the increase of drought assessment period; drought characteristics present low intra - annual and inter - annual variability but are clearly associated to the temporal and spatial distribution of LW. In fact, all LW occurred during drought assessed with SPI or SPEI, almost all LW (97% to 95%) and corresponding burnt area (98% to 97%) occurred during drought assessed with SPI and SPEI. The relationship between drought and fire incidence is statistical significant for 3 - month SPI, 3 - and 6 - month SPEI, and is particularly strong for Moderate and Severe drought. 85% and 87% of LW occurred in area affected by drought assessed with SPI or SPEI, respectively. It is not clear which is the best index, but drought plays a fundamental role in the occurrence of large wildfires in Portugal.
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Affiliation(s)
- J Parente
- Centre for Research and Technology of Agro-Environment and Biological Sciences, CITAB, University of Trás-os-Montes and Alto Douro, Portugal.
| | - M Amraoui
- Centre for Research and Technology of Agro-Environment and Biological Sciences, CITAB, University of Trás-os-Montes and Alto Douro, Portugal.
| | - I Menezes
- ICAAM, Universidade de Évora, Évora, Portugal; DREAMS, Universidade Lusófona de Humanidades e Tecnologia, Lisboa, Portugal.
| | - M G Pereira
- Centre for Research and Technology of Agro-Environment and Biological Sciences, CITAB, University of Trás-os-Montes and Alto Douro, Portugal; Instituto Dom Luiz, IDL, University of Lisbon, Lisbon, Portugal.
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Regional and Local Moisture Gradients Drive the Resistance to and Recovery from Drought of Picea crassifolia Kom. in the Qilian Mountains, Northwest China. FORESTS 2019. [DOI: 10.3390/f10090817] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Increasing evidence suggests that extreme droughts cause more frequent tree growth reduction. To understand the consequences of these droughts better, this study used tree-ring cores from nine sites to investigate how moisture and altitudinal gradients affect the radial growth of Picea crassifolia Kom., a common species in the Qilian Mountains in northwest China. The total annual precipitation and mean annual temperature in the eastern region were higher than those in the western region of the Qilian Mountains. The trees in the eastern region showed stronger resistance to drought than those in the west, as they had a smaller difference in radial growth between drought disturbance and pre-drought disturbance. At the same time, the trees in the east showed weaker ability to recover from drought, as they had a subtle difference in radial growth between post-drought disturbance and drought disturbance. Furthermore, the trees in the east also showed weaker relative resilience to drought, as they had a small difference in radial growth between post-drought and drought disturbance weighted by growth in pre-drought disturbance. For trees below 3000 m a.s.l., trees with high resistance capacity usually had low recovery capacity and low relative resilience capacity. Trees at higher altitudes also showed stronger resistance to drought and weaker ability to recover from drought after a drought event than those at lower altitudes in the middle of the Qilian Mountains. Trees at lower altitudes in the middle of the Qilian Mountains had more difficulties recovering from more severe and longer drought events. In the context of global warming, trees in the western region and at lower altitudes should be given special attention and protection in forest management to enhance their resistance to extreme droughts.
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An Assessment of Woody Plant Water Source Studies from across the Globe: What Do We Know after 30 Years of Research and Where Do We Go from Here? HYDROLOGY 2019. [DOI: 10.3390/hydrology6020040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the face of global climate change, water availability and its impact on forest productivity is becoming an increasingly important issue. It is therefore necessary to evaluate the advancement of research in this field and to set new research priorities. A systematic literature review was performed to evaluate the spatiotemporal dynamics of global research on woody plant water sources and to determine a future research agenda. Most of the reviewed studies were from the United States, followed by China and Australia. The research indicates that there is a clear variation in woody plant water sources in forests due to season, climate, leaf phenology, and method of measurement. Much of the research focus has been on identifying plant water sources using a single isotope approach. Much less focus has been given to the nexus between water source and tree size, tree growth, drought, water use efficiency, agroforestry systems, groundwater interactions, and many other topics. Therefore, a new set of research priorities has been proposed that will address these gaps under different vegetation and climate conditions. Once these issues are resolved, the research can inform forest process studies in new ways.
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