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Xiao J, Yu C, Fu G. Response of Aboveground Net Primary Production, Species and Phylogenetic Diversity to Warming and Increased Precipitation in an Alpine Meadow. PLANTS (BASEL, SWITZERLAND) 2023; 12:3017. [PMID: 37687264 PMCID: PMC10490440 DOI: 10.3390/plants12173017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 08/10/2023] [Accepted: 08/18/2023] [Indexed: 09/10/2023]
Abstract
The uncertain responses of aboveground net primary productivity (ANPP) and plant diversity to climate warming and increased precipitation will limit our ability to predict changes in vegetation productivity and plant diversity under future climate change and further constrain our ability to protect biodiversity and ecosystems. A long-term experiment was conducted to explore the responses of ANPP, plant species, phylogenetic α-diversity, and community composition to warming and increased precipitation in an alpine meadow of the Northern Tibet from 2014 to 2019. Coverage, height, and species name were obtained by conventional community investigation methods, and ANPP was obtained using observed height and coverage. Open-top chambers with two different heights were used to simulate low- and high-level climate warming. The low- and high-level increased precipitation treatments were achieved by using two kinds of surface area funnel devices. The high-level warming reduced sedge ANPP (ANPPsedge) by 62.81%, species richness (SR) by 21.05%, Shannon by 13.06%, and phylogenetic diversity (PD) by 14.48%, but increased forb ANPP (ANPPforb) by 56.65% and mean nearest taxon distance (MNTD) by 33.88%. Species richness, Shannon, and PD of the high-level warming were 19.64%, 9.67%, and 14.66% lower than those of the low-level warming, respectively. The high-level warming-induced dissimilarity magnitudes of species and phylogenetic composition were greater than those caused by low-level warming. The low- rather than high-level increased precipitation altered species and phylogenetic composition. There were significant inter-annual variations of ANPP, plant species, phylogenetic α-diversity and community composition. Therefore, climate warming and increased precipitation had non-linear effects on ANPP and plant diversity, which were due to non-linear changes in temperature, water availability, and/or soil nutrition caused by warming and increased precipitation. The inter-annual variations of ANPP and plant diversity were stronger than the effects of warming and especially increased precipitation on ANPP and plant diversity. In terms of plant diversity conservation and related policy formulation, we should pay more attention to regions with greater warming, at least for the northern Tibet grasslands. Besides paying attention to the responses of ANPP and plant diversity to climate change, the large inter-annual changes of ANPP and plant diversity should be given great attention because the large inter-annual variation indicates the low temporal stability of ANPP and plant diversity and thus produces great uncertainty for the development of animal husbandry.
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Affiliation(s)
- Jianyu Xiao
- Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; (J.X.); (C.Y.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chengqun Yu
- Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; (J.X.); (C.Y.)
| | - Gang Fu
- Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; (J.X.); (C.Y.)
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Han F, Yu C, Fu G. Temperature sensitivities of aboveground net primary production, species and phylogenetic diversity do not increase with increasing elevation in alpine grasslands. Glob Ecol Conserv 2023. [DOI: 10.1016/j.gecco.2023.e02464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
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Zhan J, Li Y, Zhao X, Yang H, Ning Z, Zhang R. Effects of nitrogen addition and plant litter manipulation on soil fungal and bacterial communities in a semiarid sandy land. Front Microbiol 2023; 14:1013570. [PMID: 37051518 PMCID: PMC10083410 DOI: 10.3389/fmicb.2023.1013570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 03/07/2023] [Indexed: 03/29/2023] Open
Abstract
The plant and soil microbial communities are influenced by variability in environmental conditions (e.g., nitrogen addition); however, it is unclear how long-term nitrogen addition and litter manipulation affect soil microbial communities in a semiarid sandy grassland. Therefore, we simulated the impact of N addition and litter manipulation (litter removal, litter doubling) on plant and soil microbial communities in Horqin grassland, northern China through an experiment from 2014 to 2019. Our results revealed that in the case of non-nitrogen (N0), litter manipulation significantly reduced vegetation coverage (V) (p < 0.05); soil bacterial communities have higher alpha diversity than that of the fungi, and the beta diversity of soil fungi was higher than that of the bacteria; soil microbial alpha diversity was significantly decreased by nitrogen addition (N10) (p < 0.05); N addition and litter manipulation had significantly interactive influences on soil microbial beta diversity, and litter manipulation (C0 and C2) had significantly decreased soil microbial beta diversity (p < 0.05) in the case of nitrogen addition (N10) (p < 0.05). Moreover, bacteria were mostly dominated by the universal phyla Proteobacteria, Actinobacteria, and Acidobacteria, and fungi were only dominated by Ascomycota. Furthermore, the correlation analysis, redundancy analysis (RDA), and variation partitioning analysis indicated that the soil fungi community was more apt to be influenced by plant community diversity. Our results provide evidence that plant and soil microbial community respond differently to the treatments of the 6-year N addition and litter manipulation in a semiarid sandy land.
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Affiliation(s)
- Jin Zhan
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Yulin Li
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- *Correspondence: Yulin Li,
| | - Xueyong Zhao
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Hongling Yang
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Zhiying Ning
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Rui Zhang
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
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Idbella M, De Filippis F, Zotti M, Sequino G, Abd-ElGawad AM, Fechtali T, Mazzoleni S, Bonanomi G. Specific microbiome signatures under the canopy of Mediterranean shrubs. APPLIED SOIL ECOLOGY 2022; 173:104407. [DOI: 10.1016/j.apsoil.2022.104407] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Diverse Understory Vegetation Alleviates Nitrogen Competition with Crop Trees in Poplar Plantations. FORESTS 2021. [DOI: 10.3390/f12060705] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Understory vegetation plays a crucial role in nutrient turnover and cycling in plantations, but it also competes for nutrients with crop trees when only a single species is present due to its specific nutrient requirements. However, it remains unclear whether this competition can be alleviated when the species richness of understory vegetation increases. In this study, we tested different gradients of understory vegetation species richness, including understory vegetation removal (UR), the retention of a single main understory vegetation species (RS), and the retention of natural diverse understory vegetation (RD) as part of a poplar (Populus deltoides ‘Nanlin-3804′) plantation, to study their effects on poplar growth, and to evaluate nitrogen (N) usage and how this was affected by the interactions between the poplar and understory vegetation. The results showed a generally lower periodic growth, and a significant decline in the foliar chlorophyll content and glutamine synthetase activity of poplar under treatment with RS and RD compared to those under UR treatment conducted in July 2019, which clearly indicated N competition between the understory vegetation and poplar trees. However, no significant difference was detected in the foliar chlorophyll content and glutamine synthetase activity of poplar under RD and RS treatment; only the nitrate reductase activity in poplar leaves under RD treatment declined significantly, by 22.25%, in June 2019. On the contrary, the diameter at breast height (DBH) of the poplar under RD treatment showed an increase of 34.69% from July to August 2019, compared with that under RS treatment. Furthermore, the increase in the species richness of understory vegetation resulted in an increase in the δ15N values in the poplar leaves, which was strongly regulated by the NH4+-N pool in the 10–20 cm soil layer, indicating the effective coordination of N utilization between poplar and understory vegetation when diversified understory plant species were present. These findings demonstrate the essential role of understory vegetation species diversity in alleviating N competition with crop trees, and provide guidance for understory vegetation management in poplar plantations.
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Ren Z, Zhang Y, Zhang Y. Nitrogen deposition magnifies the positive response of plant community production to precipitation: Ammonium to nitrate ratio matters. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 276:116659. [PMID: 33621734 DOI: 10.1016/j.envpol.2021.116659] [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: 11/14/2020] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
The impacts of atmospheric nitrogen (N) deposition amount on plant communities have been extensively explored. However, the responses of plant communities to the ratio of reduced (NH4+-N) and oxidized (NO3--N) forms remain unclear in natural ecosystems. A field N enrichment experiment using different NH4+-N/NO3--N ratios was conducted in a natural semi-arid grassland in northern China from 2014 to 2019. Nitrogen addition tended to reduce plant species richness and significantly enhanced plant community aboveground net primary productivity (ANPP). Neither plant species richness nor plant ANPP at species and community levels was significantly affected by NH4+-N/NO3--N ratios. At the plant functional group level, ANPP of grasses was not significantly affected by the NH4+-N/NO3--N ratios examined, whereas ANPP of forbs was significantly increased at 1:1 NH4+-N/NO3--N. Regardless of N supplied using the different ratios of NH4+-N/NO3--N examined, plant community ANPP was positively associated with growing season precipitation. Unexpectedly, 1:1 NH4+-N/NO3--N (NH4NO3) significantly improved the positive response of plant community ANPP to precipitation (it had the biggest slope value). Our results suggest that precipitation was the main determinant of the influence of NH4+-N/NO3--N ratios on plant community ANPP. Therefore, the results of our study showed that without referring to NH4+-N/NO3--N ratios and precipitation, models using NH4NO3 enrichment may overestimate the positive effect of atmospheric N deposition on ecosystem ANPP in semi-arid ecozones.
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Affiliation(s)
- Zhengru Ren
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Yuquan Road, Beijing 100049, China
| | - Yuqiu Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Yuquan Road, Beijing 100049, China
| | - Yunhai Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Yuquan Road, Beijing 100049, China.
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Liu Y, Bai L, Sun M, Wang J, Li S, Miao L, Yan Y, He C, Yu X, Li Y. Adaptation of cucumber seedlings to low temperature stress by reducing nitrate to ammonium during it's transportation. BMC PLANT BIOLOGY 2021; 21:189. [PMID: 33874888 PMCID: PMC8056598 DOI: 10.1186/s12870-021-02918-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 03/07/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Low temperature severely depresses the uptake, translocation from the root to the shoot, and metabolism of nitrate and ammonium in thermophilic plants such as cucumber (Cucumis sativus). Plant growth is inhibited accordingly. However, the availability of information on the effects of low temperature on nitrogen transport remains limited. RESULTS Using non-invasive micro-test technology, the net nitrate (NO3-) and ammonium (NH4+) fluxes in the root hair zone and vascular bundles of the primary root, stem, petiole, midrib, lateral vein, and shoot tip of cucumber seedlings under normal temperature (NT; 26 °C) and low temperature (LT; 8 °C) treatment were analyzed. Under LT treatment, the net NO3- flux rate in the root hair zone and vascular bundles of cucumber seedlings decreased, whereas the net NH4+ flux rate in vascular bundles of the midrib, lateral vein, and shoot tip increased. Accordingly, the relative expression of CsNRT1.4a in the petiole and midrib was down-regulated, whereas the expression of CsAMT1.2a-1.2c in the midrib was up-regulated. The results of 15N isotope tracing showed that NO3--N and NH4+-N uptake of the seedlings under LT treatment decreased significantly compared with that under NT treatment, and the concentration and proportion of both NO3--N and NH4+-N distributed in the shoot decreased. Under LT treatment, the actual nitrate reductase activity (NRAact) in the root did not change significantly, whereas NRAact in the stem and petiole increased by 113.2 and 96.2%, respectively. CONCLUSIONS The higher net NH4+ flux rate in leaves and young tissues may reflect the higher NRAact in the stem and petiole, which may result in a higher proportion of NO3- being reduced to NH4+ during the upward transportation of NO3-. The results contribute to an improved understanding of the mechanism of changes in nitrate transportation in plants in response to low-temperature stress.
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Affiliation(s)
- Yumei Liu
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
- College of Agricultural and Biological Engineering, Heze University, Heze, 274000 Shandong China
| | - Longqiang Bai
- College of Horticulture, Shanxi Agricultural University, Taigu, 030801 Shanxi China
| | - Mintao Sun
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Jun Wang
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Shuzhen Li
- College of Life Science, Gannan Normal University, Ganzhou, 341000 Jiangxi China
| | - Li Miao
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Yan Yan
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Chaoxing He
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Xianchang Yu
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Yansu Li
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
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Differential resource use in filter-feeding marine invertebrates. Oecologia 2020; 194:505-513. [PMID: 33079267 DOI: 10.1007/s00442-020-04791-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Abstract
Coexistence theory predicts that, in general, increases in the number of limiting resources shared among competitors should facilitate coexistence. Heterotrophic sessile marine invertebrate communities are extremely diverse but traditionally, space was viewed as the sole limiting resource. Recently planktonic food was recognized as an additional limiting resource, but the degree to which planktonic food acts as a single resource or is utilized differentially remains unclear. In other words, whether planktonic food represents a single resource niche or multiple resource niches has not been established. We estimated the rate at which 11 species of marine invertebrates consumed three phytoplankton species, each different in shape and size. Rates of consumption varied by a 240-fold difference among the species considered and, while there was overlap in the consumer diets, we found evidence for differential resource usage (i.e. consumption rates of phytoplankton differed among consumers). No consumer ingested all phytoplankton species at equivalent rates, instead most species tended to consume one of the species much more than others. Our results suggest that utilization of the phytoplankton niche by filter feeders is more subdivided than previously thought, and resource specialization may facilitate coexistence in this system. Our results provide a putative mechanism for why diversity affects community function and invasion in a classic system for studying competition.
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Liu S, Chi Q, Cheng Y, Zhu B, Li W, Zhang X, Huang Y, Müller C, Cai Z, Zhang J. Importance of matching soil N transformations, crop N form preference, and climate to enhance crop yield and reducing N loss. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 657:1265-1273. [PMID: 30677893 DOI: 10.1016/j.scitotenv.2018.12.100] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/06/2018] [Accepted: 12/07/2018] [Indexed: 06/09/2023]
Abstract
The preferential uptake of nitrogen (N) by plant species is generally considered to be tightly associated with soil N transformation characteristics and climatic conditions. In the present study, the yield, N recovery, and N balance of wheat (an NO3--preferring crop) and rice (an NH4+-preferring crop) planted in two sites with significantly different soil N transformations and precipitation were compared to test the connections among soil N transformations, species-specific N preferences, crop yield, N use efficiency (NUE), N loss, and climate. Nitrogen recoveries of 15N applied as either an NH4+ or NO3- based fertilizer in crops and soil were determined, and N losses were calculated using the 15N balance. The results indicated that the match (or mismatch) of crop N preference, soil N transformation characteristics, and climate conditions could significantly affect the crop yield, recovery, and loss of applied 15N. A crop preferring NH4+ (e.g., rice) planted in soil with low nitrification and low pH tended to have a higher yield and NUE, and a lower N loss compared with plants growing in soil characterized by a higher nitrification rates. In contrast, NO3--preferring crops (e.g. wheat) planted in soil with higher nitrification rates and lower precipitation achieved a higher yield and lower N loss than those planted in acid soil with a lower nitrification rate and higher precipitation. Replacement of ammonium N fertilizer with nitrate N fertilizer improved the NUE for NO3--preferring crops (wheat) planted in arid and semi-arid regions, but not in humid regions because of the mobility of NO3-. Thus, a good match of crop N preference, soil N transformation characteristics, and climate conditions is critical to enhance crop yield and reduce N loss. This intimate connection needs to be taken into consideration in terms of the choice of crop species and N fertilizer type to optimize N fertilization management.
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Affiliation(s)
- Siyi Liu
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China
| | - Qiaodong Chi
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China
| | - Yi Cheng
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China.
| | - Bo Zhu
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, No. 9, Section 4 of Renmin Nan road, Chengdu 610041, China
| | - Wenzhou Li
- Daiyun Mountain National Nature Reserve, Dehua, Fujian 362500, China
| | - Xifeng Zhang
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, No. 9, Section 4 of Renmin Nan road, Chengdu 610041, China
| | - Yaqiong Huang
- Daiyun Mountain National Nature Reserve, Dehua, Fujian 362500, China
| | - Christoph Müller
- Department of Plant Ecology (IFZ), Justus-Liebig University Giessen, Heinrich-Buff-Ring 26, 35392 Giessen, Germany; School of Biology and Environmental Science, University College Dublin, Ireland
| | - Zucong Cai
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, China
| | - Jinbo Zhang
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, China; Key Laboratory of Vitual Geographical Environment (VGE), Ministry of Education, Nanjing Normal University, China.
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Graff P, Aguiar MR. Do species' strategies and type of stress predict net positive effects in an arid ecosystem? Ecology 2017; 98:794-806. [PMID: 27987317 DOI: 10.1002/ecy.1703] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 10/26/2016] [Accepted: 12/08/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Pamela Graff
- IFEVA; CONICET and Facultad de Agronomía, Universidad of Buenos Aires; Av. San Martín 4453 C1417DSE Ciudad de Buenos Aires Argentina
| | - Martin R. Aguiar
- IFEVA; CONICET and Facultad de Agronomía, Universidad of Buenos Aires; Av. San Martín 4453 C1417DSE Ciudad de Buenos Aires Argentina
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van Voorn G, Kooi B, Bregt A. Over-shading is critical for inducing a regime shift from heathland to grassland under nitrogen enrichment. ECOLOGICAL COMPLEXITY 2016. [DOI: 10.1016/j.ecocom.2015.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Gherardi LA, Sala OE. Enhanced interannual precipitation variability increases plant functional diversity that in turn ameliorates negative impact on productivity. Ecol Lett 2015; 18:1293-300. [PMID: 26437913 DOI: 10.1111/ele.12523] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 05/27/2015] [Accepted: 08/27/2015] [Indexed: 11/30/2022]
Abstract
Although precipitation interannual variability is projected to increase due to climate change, effects of changes in precipitation variance have received considerable less attention than effects of changes in the mean state of climate. Interannual precipitation variability effects on functional diversity and its consequences for ecosystem functioning are assessed here using a 6-year rainfall manipulation experiment. Five precipitation treatments were switched annually resulting in increased levels of precipitation variability while maintaining average precipitation constant. Functional diversity showed a positive response to increased variability due to increased evenness. Dominant grasses decreased and rare plant functional types increased in abundance because grasses showed a hump-shaped response to precipitation with a maximum around modal precipitation, whereas rare species peaked at high precipitation values. Increased functional diversity ameliorated negative effects of precipitation variability on primary production. Rare species buffered the effect of precipitation variability on the variability in total productivity because their variance decreases with increasing precipitation variance.
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Affiliation(s)
- Laureano A Gherardi
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA
| | - Osvaldo E Sala
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA.,School of Sustainability, Arizona State University, Tempe, AZ, 85287-4501, USA
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Roiloa SR, Antelo B, Retuerto R. Physiological integration modifies δ15N in the clonal plant Fragaria vesca, suggesting preferential transport of nitrogen to water-stressed offspring. ANNALS OF BOTANY 2014; 114:399-411. [PMID: 24769538 PMCID: PMC4111385 DOI: 10.1093/aob/mcu064] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/05/2014] [Indexed: 05/20/2023]
Abstract
BACKGROUND AND AIMS One of the most striking attributes of clonal plants is their capacity for physiological integration, which enables movement of essential resources between connected ramets. This study investigated the capacity of physiological integration to buffer differences in resource availability experienced by ramets of the clonal wild strawberry plant, Fragaria vesca. Specifically, a study was made of the responses of connected and severed offspring ramets growing in environments with different water availability conditions (well watered or water stressed) and nitrogen forms (nitrate or ammonium). METHODS The experimental design consisted of three factors, 'integration' (connected, severed) 'water status' (well watered, water stressed) and 'nitrogen form' (nitrate, ammonium), applied in a pot experiment. The effects of physiological integration were studied by analysing photochemical efficiency, leaf spectral reflectance, photosynthesis and carbon and nitrogen isotope discrimination, the last of which has been neglected in previous studies. KEY RESULTS Physiological integration buffered the stress caused by water deprivation. As a consequence, survival was improved in water-stressed offspring ramets that remained connected to their parent plants. The nitrogen isotope composition (δ(15)N) values in the connected water-stressed ramets were similar to those in ramets in the ammonium treatment; however, δ(15)N values in connected well-watered ramets were similar to those in the nitrate treatment. The results also demonstrated the benefit of integration for offspring ramets in terms of photochemical activity and photosynthesis. CONCLUSIONS This is the first study in which carbon and nitrogen isotopic discrimination has been used to detect physiological integration in clonal plants. The results for nitrogen isotope composition represent the first evidence of preferential transport of a specific form of nitrogen to compensate for stressful conditions experienced by a member clone. Water consumption was lower in plants supplied with ammonium than in plants supplied with nitrate, and therefore preferential transport of ammonium from parents to water-stressed offspring could potentially optimize the water use of the whole clone.
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Affiliation(s)
- S R Roiloa
- Department of Animal Biology, Plant Biology and Ecology, Faculty of Sciences, University of A Coruña, 15071, A Coruña, Spain
| | - B Antelo
- Ecology Unit, Faculty of Biology, University of Santiago de Compostela, 15782, Spain
| | - R Retuerto
- Ecology Unit, Faculty of Biology, University of Santiago de Compostela, 15782, Spain
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