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Mosquera GM, Marín F, Carabajo-Hidalgo A, Asbjornsen H, Célleri R, Crespo P. Ecohydrological assessment of the water balance of the world's highest elevation tropical forest (Polylepis). THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 941:173671. [PMID: 38825194 DOI: 10.1016/j.scitotenv.2024.173671] [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: 07/05/2023] [Revised: 05/15/2024] [Accepted: 05/29/2024] [Indexed: 06/04/2024]
Abstract
Polylepis trees grow at elevations above the continuous tree line (3000-5000 m a.s.l.) across the Andes. They tolerate extreme environmental conditions, making them sensitive bioindicators of global climate change. Therefore, investigating their ecohydrological role is key to understanding how the water cycle of Andean headwaters could be affected by predicted changes in environmental conditions, as well as ongoing Polylepis reforestation initiatives in the region. We estimate, for the first time, the annual water balance of a mature Polylepis forest (Polylepis reticulata) catchment (3780 m a.s.l.) located in the south Ecuadorian páramo using a unique set of field ecohydrological measurements including gross rainfall, throughfall, streamflow, and xylem sap flow in combination with the characterization of forest and soil features. We also compare the forest water balance with that of a tussock grass (Calamagrostis intermedia) catchment, the dominant páramo vegetation. Annual gross rainfall during the study period (April 2019-March 2020) was 1290.6 mm yr-1. Throughfall in the Polylepis forest represented 61.2 % of annual gross rainfall. Streamflow was the main component of the water balance of the forested site (59.6 %), while its change in soil water storage was negligible (<1 %). Forest evapotranspiration was 54.0 %, with evaporation from canopy interception (38.8 %) more than twice as high as transpiration (15.1 %). The error in the annual water balance of the Polylepis catchment was small (<15 %), providing confidence in the measurements and assumptions used to estimate its components. In comparison, streamflow and evapotranspiration at the grassland site accounted for 63.7 and 36.0 % of the water balance, respectively. Although evapotranspiration was larger in the forest catchment, its water yield was only marginally reduced (<4 %) in relation to the grassland catchment. The substantially higher soil organic matter content in the forest site (47.6 %) compared to the grassland site (31.8 %) suggests that even though Polylepis forests do not impair the hydrological function of high-Andean catchments, their presence contributes to carbon storage in the litter layer of the forest and the underlying soil. These findings provide key insights into the vegetation-water‑carbon nexus in high Andean ecosystems, which can serve as a basis for future ecohydrological studies and improved management of páramo natural resources considering changes in land use and global climate.
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Affiliation(s)
- Giovanny M Mosquera
- Departamento de Recursos Hídricos y Ciencias Ambientales (iDRHICA), Universidad de Cuenca, Cuenca, Ecuador; Departamento de Ingeniería & Grupo de Glaciología y Ecohidrología de Montañas Andinas (GEMS), Pontificia Universidad Católica del Perú (PUCP), Lima, Peru.
| | - Franklin Marín
- Facultad de Ciencias Agropecuarias, Carrera de Ingeniería Agronómica, Universidad de Cuenca, Cuenca, Ecuador; Laboratory of Quantitative Forest Ecosystem Science, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Belgium
| | - Aldemar Carabajo-Hidalgo
- Departamento de Recursos Hídricos y Ciencias Ambientales (iDRHICA), Universidad de Cuenca, Cuenca, Ecuador; Departamento de Biología Evolutiva, Ecología y Ciencias Ambientales, Universidad de Barcelona, Barcelona, Spain
| | - Heidi Asbjornsen
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, USA
| | - Rolando Célleri
- Departamento de Recursos Hídricos y Ciencias Ambientales (iDRHICA), Universidad de Cuenca, Cuenca, Ecuador; Facultad de Ingeniería, Universidad de Cuenca, Cuenca, Ecuador
| | - Patricio Crespo
- Departamento de Recursos Hídricos y Ciencias Ambientales (iDRHICA), Universidad de Cuenca, Cuenca, Ecuador; Facultad de Ingeniería, Universidad de Cuenca, Cuenca, Ecuador.
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Araújo KC, Souza BC, Carvalho ECD, Freire RS, Teixeira AS, Muniz CR, Martins FR, Oliveira RS, Eller CB, Soares AA. The multiple roles of trichomes in two Croton species. PLANT, CELL & ENVIRONMENT 2024; 47:1685-1700. [PMID: 38282477 DOI: 10.1111/pce.14829] [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: 01/20/2020] [Revised: 01/05/2024] [Accepted: 01/10/2024] [Indexed: 01/30/2024]
Abstract
Trichomes are common in plants from dry environments, and despite their recognized role in protection and defense, little is known about their role as absorptive structures and in other aspects of leaf ecophysiology. We combine anatomical and ecophysiological data to evaluate how trichomes affect leaf gas exchange and water balance during drought. We studied two congeneric species with pubescent leaves which co-occur in Brazilian Caatinga: Croton blanchetianus (dense trichomes) and Croton adenocalyx (sparse trichomes). We found a novel foliar water uptake (FWU) pathway in C. blanchetianus composed of stellate trichomes and underlying epidermal cells and sclereids that interconnect the trichomes from both leaf surfaces. The water absorbed by these trichomes is redistributed laterally by pectin protuberances on mesophyll cell walls. This mechanism enables C. blanchetianus leaves to absorb water more efficiently than C. adenocalyx. Consequently, the exposure of C. blanchetianus to dew during drought improved its leaf gas exchange and water status more than C. adenocalyx. C. blanchetianus trichomes also increase their leaf capacity to reflect light and maintain lower temperatures during drought. Our results emphasize the multiple roles that trichomes might have on plant functioning and the importance of FWU for the ecophysiology of Caatinga plants during drought.
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Affiliation(s)
- Karina Crisóstomo Araújo
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Bruno Cruz Souza
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Ellen Cristina Dantas Carvalho
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Rosemeyre Souza Freire
- Centro de Ciências, Central Analítica, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Adunias Santos Teixeira
- Departament of Agricultural Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | - Fernando Roberto Martins
- Department of Plant Biology, Institute of Biology, CP6109, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Rafael Silva Oliveira
- Department of Plant Biology, Institute of Biology, CP6109, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Cleiton Breder Eller
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Arlete Aparecida Soares
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Ceará, Brazil
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Brum M, Vadeboncoeur M, Asbjornsen H, Puma Vilca BL, Galiano D, Horwath AB, Metcalfe DB. Ecophysiological controls on water use of tropical cloud forest trees in response to experimental drought. TREE PHYSIOLOGY 2023; 43:1514-1532. [PMID: 37209136 DOI: 10.1093/treephys/tpad070] [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: 02/18/2023] [Revised: 05/03/2023] [Accepted: 05/17/2023] [Indexed: 05/22/2023]
Abstract
Tropical montane cloud forests (TMCFs) are expected to experience more frequent and prolonged droughts over the coming century, yet understanding of TCMF tree responses to moisture stress remains weak compared with the lowland tropics. We simulated a severe drought in a throughfall reduction experiment (TFR) for 2 years in a Peruvian TCMF and evaluated the physiological responses of several dominant species (Clusia flaviflora Engl., Weinmannia bangii (Rusby) Engl., Weinmannia crassifolia Ruiz & Pav. and Prunus integrifolia (C. Presl) Walp). Measurements were taken of (i) sap flow; (ii) diurnal cycles of stem shrinkage, stem moisture variation and water-use; and (iii) intrinsic water-use efficiency (iWUE) estimated from foliar δ13C. In W. bangii, we used dendrometers and volumetric water content (VWC) sensors to quantify daily cycles of stem water storage. In 2 years of sap flow (Js) data, we found a threshold response of water use to vapor pressure deficit vapor pressure deficit (VPD) > 1.07 kPa independent of treatment, though control trees used more soil water than the treatment trees. The daily decline in water use in the TFR trees was associated with a strong reduction in both morning and afternoon Js rates at a given VPD. Soil moisture also affected the hysteresis strength between Js and VPD. Reduced hysteresis under moisture stress implies that TMCFs are strongly dependent on shallow soil water. Additionally, we suggest that hysteresis can serve as a sensitive indicator of environmental constraints on plant function. Finally, 6 months into the experiment, the TFR treatment significantly increased iWUE in all study species. Our results highlight the conservative behavior of TMCF tree water use under severe soil drought and elucidate physiological thresholds related to VPD and its interaction with soil moisture. The observed strongly isohydric response likely incurs a cost to the carbon balance of the tree and reduces overall ecosystem carbon uptake.
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Affiliation(s)
- Mauro Brum
- Department of Natural Resources & the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
| | - Matthew Vadeboncoeur
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Heidi Asbjornsen
- Department of Natural Resources & the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Beisit L Puma Vilca
- Facultad de Ciencias Biológicas, Universidad Nacional de San Antonio Abad del Cusco, Av. de La Cultura 773, Cusco, Cusco Province 08000, Peru
- Asociación Civil Sin Fines De Lucro Para La Biodiversidad, Investigación Y Desarrollo Ambiental En Ecosistemas Tropicales (ABIDA), Urbanización Ucchullo Grande, Avenida Argentina F-9, Cusco, Perú
| | - Darcy Galiano
- Facultad de Ciencias Biológicas, Universidad Nacional de San Antonio Abad del Cusco, Av. de La Cultura 773, Cusco, Cusco Province 08000, Peru
- Asociación Civil Sin Fines De Lucro Para La Biodiversidad, Investigación Y Desarrollo Ambiental En Ecosistemas Tropicales (ABIDA), Urbanización Ucchullo Grande, Avenida Argentina F-9, Cusco, Perú
| | - Aline B Horwath
- Asociación Civil Sin Fines De Lucro Para La Biodiversidad, Investigación Y Desarrollo Ambiental En Ecosistemas Tropicales (ABIDA), Urbanización Ucchullo Grande, Avenida Argentina F-9, Cusco, Perú
| | - Daniel B Metcalfe
- Department of Ecology & Environmental Science, Umeå University, KBC-huset, Linnaeus väg 6, Umeå 901 87, Sweden
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Losso A, Dämon B, Hacke U, Mayr S. High potential for foliar water uptake in early stages of leaf development of three woody angiosperms. PHYSIOLOGIA PLANTARUM 2023; 175:e13961. [PMID: 37341178 PMCID: PMC10953411 DOI: 10.1111/ppl.13961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/06/2023] [Accepted: 06/16/2023] [Indexed: 06/22/2023]
Abstract
Foliar water uptake (FWU) is a widespread mechanism that may help plants cope with drought stress in a wide range of ecosystems. FWU can be affected by various leaf traits, which change during leaf development. We exposed cut and dehydrated leaves to rainwater and measured FWU, changes in leaf water potential after 19 h of FWU (ΔΨ), minimum leaf conductance (gmin ), and leaf wettability (abaxial and adaxial) of leaves of Acer platanoides, Fagus sylvatica, and Sambucus nigra at three developmental stages: unfolding (2-5-day-old), young (1.5-week-old) and mature leaves (8-week-old). FWU and gmin were higher in younger leaves. ΔΨ corresponded to FWU and gmin in all cases but mature leaves of F. sylvatica, where ΔΨ was highest. Most leaves were highly wettable, and at least one leaf surface (adaxial or abaxial) showed a decrease in wettability from unfolding to mature leaves. Young leaves of all studied species showed FWU (unfolding leaves: 14.8 ± 1.1 μmol m-2 s-1 ), which may improve plant water status and thus counterbalance spring transpirational losses due to high gmin . The high wettability of young leaves probably supported FWU. We observed particularly high FWU and respective high ΔΨ in older leaves of F. sylvatica, possibly aided by trichomes.
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Affiliation(s)
- Adriano Losso
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - Birgit Dämon
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - Uwe Hacke
- Department of Renewable ResourcesUniversity of AlbertaEdmontonAlbertaCanada
| | - Stefan Mayr
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
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Ramírez BH, Cortés‐B R, Pinzón OP, Gómez L, Jacquin S, Hernández E, Quimbayo LA, Bogotá‐A RG. Cloud forests of the Orinoco River Basin (Colombia): Variation in vegetation and soil macrofauna composition along the hydrometeorological gradient. Biotropica 2023. [DOI: 10.1111/btp.13203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Affiliation(s)
- Beatriz H. Ramírez
- Maestría en Manejo, Uso y Conservación del Bosque Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
- Centro de Estudios Ambientales de la Orinoquia ‐CEAO ABC Colombia Yopal Colombia
| | - Rocío Cortés‐B
- Maestría en Manejo, Uso y Conservación del Bosque Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
- Ingeniería Forestal Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
| | - Olga Patricia Pinzón
- Maestría en Manejo, Uso y Conservación del Bosque Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
- Ingeniería Forestal Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
| | - Laura Gómez
- Ingeniería Forestal Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
| | - Santiago Jacquin
- Ingeniería Forestal Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
| | - Eduardo Hernández
- Ingeniería Forestal Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
| | - Luz Angélica Quimbayo
- Ingeniería Forestal Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
| | - Raúl Giovanni Bogotá‐A
- Maestría en Manejo, Uso y Conservación del Bosque Universidad Distrital Francisco José de Caldas ‐UDFJC Bogotá Colombia
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Yan X, Chang Y, Zhao W, Qian C, Yin X, Fan X, Zhu X, Zhao X, Ma XF. Transcriptome profiling reveals that foliar water uptake occurs with C 3 and crassulacean acid metabolism facultative photosynthesis in Tamarix ramosissima under extreme drought. AOB PLANTS 2022; 14:plab060. [PMID: 35047161 PMCID: PMC8763614 DOI: 10.1093/aobpla/plab060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 01/14/2022] [Indexed: 05/21/2023]
Abstract
Tamarix ramosissima is a typical desert plant species that is widely distributed in the desert areas of Northwest China. It plays a significant role in sand fixation and soil water conservation. In particular, how it uses water to survive in the desert plays an important role in plant growth and ecosystem function. Previous studies have revealed that T. ramosissima can alleviate drought by absorbing water from its leaves under extreme drought conditions. To date, there is no clear molecular regulation mechanism to explain foliar water uptake (FWU). In the present study, we correlated diurnal meteorological data, sap flow and photosynthetic parameters to determine the physical and biological characteristics of FWU. Our results suggested that the lesser the groundwater, the easier it is for T. ramosissima to absorb water via the leaves. Gene ontology annotation and Kyoto Encyclopaedia of Genes and Genomes pathway analysis of the transcriptome profile of plants subjected to high humidity suggested that FWU was highly correlated to carbohydrate metabolism, energy transfer, pyruvate metabolism, hormone signal transduction and plant-pathogen interaction. Interestingly, as a C3 plant, genes such as PEPC, PPDK, MDH and RuBP, which are involved in crassulacean acid metabolism (CAM) photosynthesis, were highly upregulated and accompanied by FWU. Therefore, we proposed that in the case of sufficient water supply, C3 photosynthesis is used in T. ramosissima, whereas in cases of extreme drought, starch is degraded to provide CO2 for CAM photosynthesis to make full use of the water obtained via FWU and the water that was transported or stored to assimilating branches and stems. This study may provide not only an important theoretical foundation for FWU and conversion from C3 plants to CAM plants but also for engineering improved photosynthesis in high-yield drought-tolerant plants and mitigation of climate change-driven drought.
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Affiliation(s)
- Xia Yan
- School of Life Sciences, Nantong University, Nantong 226019, Jiangsu, China
- Key Laboratory of Inland River Ecohydrology, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
| | - Yan Chang
- School of Life Sciences, Nantong University, Nantong 226019, Jiangsu, China
| | - Weijia Zhao
- School of Life Sciences, Nantong University, Nantong 226019, Jiangsu, China
| | - Chaoju Qian
- Key Laboratory of Stress Physiology and Ecology in Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
| | - Xiaoyue Yin
- Key Laboratory of Stress Physiology and Ecology in Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xingke Fan
- Key Laboratory of Stress Physiology and Ecology in Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinyu Zhu
- School of Life Sciences, Nantong University, Nantong 226019, Jiangsu, China
| | - Xiangqiang Zhao
- School of Life Sciences, Nantong University, Nantong 226019, Jiangsu, China
| | - Xiao-Fei Ma
- School of Life Sciences, Nantong University, Nantong 226019, Jiangsu, China
- Key Laboratory of Stress Physiology and Ecology in Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
- Corresponding author’s e-mail address:
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Araújo EA, Kunz SH, Dias HM, Zorzanelli JPF, Callegaro RM. Vascular plant checklist in an area of extreme biological importance: filling gaps in the Caparaó National Park-ES, Brazil. BIOTA NEOTROPICA 2021. [DOI: 10.1590/1676-0611-bn-2020-1024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract Regional floristic lists are essential for defining biodiversity conservation strategies and are key to assist in filling knowledge gaps. They aim to provide a data source for applying tools to reduce extinction rates and to conserve ecosystems. Herein we present the results of an inventory of vascular plants in a rainforest in the Caparaó National Park (CNP) and approach their implications for conservation and management of this protected area and the surrounding communities. We conducted botanical expeditions between the years 2012 and 2017 in a montane and upper-montane forest of the CNP. We found 361 species distributed in 78 families and 181 genera. The study area is home to new species for science that have recently been described in other publications outside that location, and 4 new records for Espírito Santo State; also 43 species listed in different extinction threat categories (VU, EN and CR) and another 190 categorized with lesser concerns (LC and NT). The families with the highest species richness were: Melastomataceae (41 spp.), Lauraceae and Myrtaceae (30), Orchidaceae (26), Rubiaceae (24), and Asteraceae (20). Our results contribute to greater knowledge of the CNP flora, of the montane environments in Brazil and the vegetation of Espírito Santo state, in addition to demonstrate the importance of this protected area to the conservation Atlantic Forest biodiversity.
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Schreel JDM, Steppe K. Foliar Water Uptake in Trees: Negligible or Necessary? TRENDS IN PLANT SCIENCE 2020; 25:590-603. [PMID: 32407698 DOI: 10.1016/j.tplants.2020.01.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 01/06/2020] [Accepted: 01/15/2020] [Indexed: 06/11/2023]
Abstract
Foliar water uptake (FWU) has been identified as a mechanism commonly used by trees and other plants originating from various biomes. However, many questions regarding the pathways and the implications of FWU remain, including its ability to mitigate climate change-driven drought. Therefore, answering these questions is of primary importance to adequately address and comprehend drought stress responses and associated growth. In this review, we discuss the occurrence, pathways, and consequences of FWU, with a focus predominantly on tree species. Subsequently, we highlight the tight coupling between FWU and foliar fertilizer applications, discuss FWU in a changing climate, and conclude with the importance of including FWU in mechanistic vegetation models.
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Affiliation(s)
- Jeroen D M Schreel
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium.
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium.
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Forster MA. The importance of conduction versus convection in heat pulse sap flow methods. TREE PHYSIOLOGY 2020; 40:683-694. [PMID: 32031660 DOI: 10.1093/treephys/tpaa009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/07/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
Heat pulse methods are a popular approach for estimating sap flow and transpiration. Yet, many methods are unable to resolve the entire heat velocity measurement range observable in plants. Specifically, the Heat Ratio (HRM) and Tmax heat pulse methods can only resolve slow and fast velocities, respectively. The Dual Method Approach (DMA) combines optimal data from HRM and Tmax to output the entire range of heat velocity. However, the transition between slow and fast methods in the DMA currently does not have a theoretical solution. A re-consideration of the conduction/convection equation demonstrated that the HRM equation is equivalent to the Péclet equation which is the ratio of conduction to convection. This study tested the hypothesis that the transition between slow and fast methods occurs when conduction/convection, or the Péclet number, equals one, and the DMA would be improved via the inclusion of this transition value. Sap flux density was estimated via the HRM, Tmax and DMA methods and compared with gravimetric sap flux density measured via a water pressure system on 113 stems from 15 woody angiosperm species. When the Péclet number ≤ 1, the HRM yielded accurate results and the Tmax was out of range. When the Péclet number > 1, the HRM reached a maximum heat velocity at approximately 15 cm hr -1 and was no longer accurate, whereas the Tmax yielded accurate results. The DMA was able to output accurate data for the entire measurement range observed in this study. The linear regression analysis with gravimetric sap flux showed an r2 of 0.541 for HRM, 0.879 for Tmax and 0.940 for DMA. With the inclusion of the Péclet equation, the DMA resolved the entire heat velocity measurement range observed across 15 taxonomically diverse woody species. Consequently, the HRM and Tmax are redundant sap flow methods and have been superseded by the DMA.
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Affiliation(s)
- Michael A Forster
- Implexx Sense, PO BOX 285, Moorabbin, Victoria, 3189, Australia
- Edaphic Scientific Pty Ltd, PO BOX 285, Moorabbin, Victoria, 3189, Australia
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Schreel JDM, Van de Wal BAE, Hervé-Fernandez P, Boeckx P, Steppe K. Hydraulic redistribution of foliar absorbed water causes turgor-driven growth in mangrove seedlings. PLANT, CELL & ENVIRONMENT 2019; 42:2437-2447. [PMID: 30953380 DOI: 10.1111/pce.13556] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 03/25/2019] [Accepted: 04/02/2019] [Indexed: 06/09/2023]
Abstract
Although foliar water uptake (FWU) has been shown in mature Avicennia marina trees, the importance for its seedlings remains largely unknown. A series of experiments were therefore performed using artificial rainfall events in a greenhouse environment to assess the ecological implications of FWU in A. marina seedlings. One-hour artificial rainfall events resulted in an increased leaf water potential, a reversed sap flow, and a rapid diameter increment signifying a turgor-driven growth of up to 30.1 ± 5.4 μm. Furthermore, the application of an artificial rainfall event with deuterated water showed that the amount of water absorbed by the leaves and transported to the stem was directly and univocally correlated to the observed growth spurts. The observations in this process-based study show that FWU is an important water acquisition mechanism under certain circumstances and might be of ecological importance for the establishment of A. marina seedlings. Distribution of mangrove trees might hence be more significantly disturbed by climate change-driven changes in rainfall patterns than previously assumed.
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Affiliation(s)
- Jeroen D M Schreel
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, 9000, Belgium
| | - Bart A E Van de Wal
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, 9000, Belgium
| | - Pedro Hervé-Fernandez
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, 9000, Belgium
- Isotope Bioscience Laboratory (ISOFYS), Faculty of Bioscience Engineering, Ghent University, Ghent, 9000, Belgium
| | - Pascal Boeckx
- Isotope Bioscience Laboratory (ISOFYS), Faculty of Bioscience Engineering, Ghent University, Ghent, 9000, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, 9000, Belgium
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Brum M, Gutiérrez López J, Asbjornsen H, Licata J, Pypker T, Sanchez G, Oiveira RS. ENSO effects on the transpiration of eastern Amazon trees. Philos Trans R Soc Lond B Biol Sci 2018; 373:20180085. [PMID: 30297479 PMCID: PMC6178436 DOI: 10.1098/rstb.2018.0085] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2018] [Indexed: 11/12/2022] Open
Abstract
Tree transpiration is important in the recycling of precipitation in the Amazon and might be negatively affected by El Niño-Southern Oscillation (ENSO)-induced droughts. To investigate the relative importance of soil moisture deficits versus increasing atmospheric demand (VPD) and determine if these drivers exert different controls over tree transpiration during the wet season versus the dry season (DS), we conducted sap flow measurements in a primary lowland tropical forest in eastern Amazon during the most extreme ENSO-induced drought (2015/2016) recorded in the Amazon. We also assessed whether trees occupying different canopy strata contribute equally to the overall stand transpiration (Tstand). Canopy trees were the primary source of Tstand However, subcanopy trees are still important as they transpired an amount similar to other biomes around the globe. Tree water use was higher during the DS, indicating that during extreme drought trees did not reduce transpiration in response to low soil moisture. Photosynthetically active radiation and VPD exerted an overriding effect on water use patterns relative to soil moisture during extreme drought, indicating that light and atmospheric constraints play a critical role in controlling ecosystem fluxes of water. Our study highlights the importance of canopy and subcanopy trees to the regional water balance and highlights the resilience to droughts that these trees show during an extreme ENSO event.This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'.
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Affiliation(s)
- Mauro Brum
- Department of Plant Biology, Institute of Biology, CP 6109, State University of Campinas - UNICAMP, Campinas, São Paulo 13083-970, Brazil
| | - Jose Gutiérrez López
- Earth Systems Research Center, University of New Hampshire, Durham, NH 03824, USA
| | - Heidi Asbjornsen
- Earth Systems Research Center, University of New Hampshire, Durham, NH 03824, USA
| | - Julian Licata
- Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Concordia, Concordia, Entre Ríos, Argentina
| | - Thomas Pypker
- Department of Natural Resource Sciences, Thompson Rivers University, Kamloops, British Columbia, Canada V2C0C8
| | - Gilson Sanchez
- AGROPALMA Company, PA-150 Highway, No Number, Km 74, Tailândia, Pará 68695-000, Brazil
| | - Rafael S Oiveira
- Department of Plant Biology, Institute of Biology, CP 6109, State University of Campinas - UNICAMP, Campinas, São Paulo 13083-970, Brazil
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12
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Rosado BHP, Almeida LC, Alves LF, Lambais MR, Oliveira RS. The importance of phyllosphere on plant functional ecology: a phyllo trait manifesto. THE NEW PHYTOLOGIST 2018; 219:1145-1149. [PMID: 29806957 DOI: 10.1111/nph.15235] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Affiliation(s)
- Bruno H P Rosado
- Department of Ecology, IBRAG, Rio de Janeiro State University (UERJ), R. São Francisco Xavier 524, PHLC, Sala 220, Maracanã, Rio de Janeiro, RJ, Brazil
| | - Lidiane C Almeida
- Department of Ecology, IBRAG, Rio de Janeiro State University (UERJ), R. São Francisco Xavier 524, PHLC, Sala 220, Maracanã, Rio de Janeiro, RJ, Brazil
- Ecology and Evolution Graduate Program, IBRAG, Rio de Janeiro State University (UERJ), R. São Francisco Xavier 524, PHLC, Maracanã, Rio de Janeiro, RJ, Brazil
| | - Luciana F Alves
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, USA
| | - Marcio R Lambais
- Department of Soil Science, University of São Paulo, Av. Pádua Dias 11, 13418-900 Piracicaba, SP, Brazil
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, PO Box 6109, 13083-970 Campinas, SP, Brazil
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13
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Gotsch SG, Dawson TE, Draguljić D. Variation in the resilience of cloud forest vascular epiphytes to severe drought. THE NEW PHYTOLOGIST 2018; 219:900-913. [PMID: 29084355 DOI: 10.1111/nph.14866] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Epiphytes are common in tropical montane cloud forests (TMCFs) and play many important ecological roles, but the degree to which these unique plants will be affected by changes in climate is unknown. We investigated the drought responses of three vascular epiphyte communities bracketing the cloud base during a severe, El Niño-impacted dry season. Epiphytes were instrumented with sap flow probes in each site. Leaf water potential and pressure-volume curve parameters were also measured before and during the drought. We monitored the canopy microclimate in each site to determine the drivers of sap velocity across the sites. All plants greatly reduced their water use during the drought, but recovery occurred more quickly for plants in the lower and drier sites. Plants in drier sites also exhibited the greatest shifts in the osmotic potential at full saturation and the turgor loss point. Although all individuals survived this intense drought, epiphytes in the cloud forest experienced the slowest recovery, suggesting that plants in the TMCF are particularly sensitive to severe drought. Although vapor pressure deficit was an important driver of sap velocity in the highest elevation site, other factors, such as the volumetric water content of the canopy soil, were more important at lower (and warmer) sites.
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Affiliation(s)
- Sybil G Gotsch
- Department of Biology, Franklin and Marshall College, PO Box 3003, Lancaster, PA, 17603, USA
| | - Todd E Dawson
- Department of Integrative Biology, University of California at Berkeley, 4006 Valley Life Sciences Building, Berkeley, CA, 94720, USA
| | - Danel Draguljić
- Department of Mathematics, Franklin and Marshall College, PO Box 3003, Lancaster, PA, 17603, USA
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14
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Bretfeld M, Ewers BE, Hall JS. Plant water use responses along secondary forest succession during the 2015-2016 El Niño drought in Panama. THE NEW PHYTOLOGIST 2018; 219:885-899. [PMID: 29504138 DOI: 10.1111/nph.15071] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 01/22/2018] [Indexed: 05/25/2023]
Abstract
Tropical forests are increasingly being subjected to hotter, drier conditions as a result of global climate change. The effects of drought on forests along successional gradients remain poorly understood. We took advantage of the 2015-2016 El Niño event to test for differences in drought response along a successional gradient by measuring the sap flow in 76 trees, representing 42 different species, in 8-, 25- and 80-yr-old secondary forests in the 15-km2 'Agua Salud Project' study area, located in central Panama. Average sap velocities and sapwood-specific hydraulic conductivities were highest in the youngest forest. During the dry season drought, sap velocities increased significantly in the 80-yr-old forest as a result of higher evaporative demand, but not in younger forests. The main drivers of transpiration shifted from radiation to vapor pressure deficit with progressing forest succession. Soil volumetric water content was a limiting factor only in the youngest forest during the dry season, probably as a result of less root exploration in the soil. Trees in early-successional forests displayed stronger signs of regulatory responses to the 2015-2016 El Niño drought, and the limiting physiological processes for transpiration shifted from operating at the plant-soil interface to the plant-atmosphere interface with progressing forest succession.
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Affiliation(s)
- Mario Bretfeld
- ForestGEO, Smithsonian Tropical Research Institute, Av. Roosevelt 401, Balboa, Ancón, Panama
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Brent E Ewers
- Department of Botany and Program in Ecology, University of Wyoming, Laramie, WY, 82071, USA
| | - Jefferson S Hall
- ForestGEO, Smithsonian Tropical Research Institute, Av. Roosevelt 401, Balboa, Ancón, Panama
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15
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Reduced dry season transpiration is coupled with shallow soil water use in tropical montane forest trees. Oecologia 2018; 188:303-317. [PMID: 29943144 DOI: 10.1007/s00442-018-4209-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 06/15/2018] [Indexed: 10/28/2022]
Abstract
Tropical montane cloud forests (TMCF) are ecosystems particularly sensitive to climate change; however, the effects of warmer and drier conditions on TMCF ecohydrology remain poorly understood. To investigate functional responses of TMCF trees to reduced water availability, we conducted a study during the 2014 dry season in the lower altitudinal limit of TMCF in central Veracruz, Mexico. Temporal variations of transpiration, depth of water uptake and tree water sources were examined for three dominant, brevi-deciduous species using micrometeorological, sap flow and soil moisture measurements, in combination with oxygen and hydrogen stable isotope composition of rainfall, tree xylem, soil and stream water. Over the course of the dry season, reductions in crown conductance and transpiration were observed in canopy species (43 and 34%, respectively) and mid-story trees (23 and 8%), as atmospheric demand increased and soil moisture decreased. Canopy species consistently showed more depleted isotope values compared to mid-story trees. However, MixSIAR Bayesian model results showed that the evaporated (enriched) soil water pool was the main source for trees despite reduced soil moisture. Additionally, while increases in tree water uptake from deeper to shallower soil water sources occurred, concomitant decreases in transpiration were observed as the dry season progressed. A larger reduction in deep soil water use was observed for canopy species (from 79 ± 19 to 24 ± 20%) compared to mid-story trees (from 12 ± 17 to 10 ± 12%). The increase in shallower soil water sources may reflect a trade-off between water and nutrient requirements in this forest.
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16
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Eller CB, de V Barros F, Bittencourt PRL, Rowland L, Mencuccini M, Oliveira RS. Xylem hydraulic safety and construction costs determine tropical tree growth. PLANT, CELL & ENVIRONMENT 2018; 41:548-562. [PMID: 29211923 DOI: 10.1111/pce.13106] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 11/17/2017] [Indexed: 05/25/2023]
Abstract
Faster growth in tropical trees is usually associated with higher mortality rates, but the mechanisms underlying this relationship are poorly understood. In this study, we investigate how tree growth patterns are linked with environmental conditions and hydraulic traits, by monitoring the cambial growth of 9 tropical cloud forest tree species coupled with numerical simulations using an optimization model. We find that fast-growing trees have lower xylem safety margins than slow-growing trees and this pattern is not necessarily linked to differences in stomatal behaviour or environmental conditions when growth occurs. Instead, fast-growing trees have xylem vessels that are more vulnerable to cavitation and lower density wood. We propose the growth - xylem vulnerability trade-off represents a wood hydraulic economics spectrum similar to the classic leaf economic spectrum, and show through numerical simulations that this trade-off can emerge from the coordination between growth rates, wood density, and xylem vulnerability to cavitation. Our results suggest that vulnerability to hydraulic failure might be related with the growth-mortality trade-off in tropical trees, determining important life history differences. These findings are important in furthering our understanding of xylem hydraulic functioning and its implications on plant carbon economy.
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Affiliation(s)
- Cleiton B Eller
- Department of Plant Biology, Institute of Biology, UNICAMP, 6109, Campinas, Brazil
- Department of Geography, College of Life and Environmental Sciences, University of Exeter, EX4 4RJ, Exeter, UK
| | - Fernanda de V Barros
- Department of Plant Biology, Institute of Biology, UNICAMP, 6109, Campinas, Brazil
| | | | - Lucy Rowland
- Department of Geography, College of Life and Environmental Sciences, University of Exeter, EX4 4RJ, Exeter, UK
| | - Maurizio Mencuccini
- ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain
- CREAF, Cerdanyola del Valles, 08193, Barcelona, Spain
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, UNICAMP, 6109, Campinas, Brazil
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17
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Boanares D, Ferreira BG, Kozovits AR, Sousa HC, Isaias RMS, França MGC. Pectin and cellulose cell wall composition enables different strategies to leaf water uptake in plants from tropical fog mountain. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 122:57-64. [PMID: 29175637 DOI: 10.1016/j.plaphy.2017.11.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/08/2017] [Indexed: 06/07/2023]
Abstract
Leaf water uptake (LWU) has been observed in plants of different ecosystems and this process is distinct among different species. Four plant species from the Brazilian fog mountain fields were evaluated in order to detect if leaf water uptake capacity is related to the cell wall composition of leaf epidermis. LWU measurements and their relation to anatomical and biochemical traits were analyzed. Cell wall composition was verified through immunocytochemistry using monoclonal antibodies recognizing pectin compounds, and histochemistry with calcofluor white to track cellulose. Differences in LWU among the four species were clearly revealed. Two species presented higher maximum leaf water content and the lowest values of water absorption speed. The other two species presented opposite behavior, namely, low leaf water uptake and the highest values of water absorption speed. The anatomical traits associated with the cell wall composition corroborated the data on the different LWU strategies. The species with abundant detection of cellulose in their epidermal cell walls absorbed more water, but more slowly, while those with abundant detection of pectins absorbed water at a higher speed. These results indicate that cell wall composition regarding pectin and cellulose are significant for water uptake by the leaf epidermis. Pectin provides greater porosity and absorption speed, while cellulose provides greater hydrophilicity and greater water uptake capacity. Current data indicate that the composition of epidermal cell walls is a relevant trait for leaf water uptake.
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Affiliation(s)
- D Boanares
- Departamento de Botânica, Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil
| | - B G Ferreira
- Departamento de Botânica, Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil
| | - A R Kozovits
- Departamento de Biodiversidade, Evolução e Meio Ambiente, Universidade Federal de Ouro Preto, 35400-000, MG, Brazil
| | - H C Sousa
- Departamento de Biodiversidade, Evolução e Meio Ambiente, Universidade Federal de Ouro Preto, 35400-000, MG, Brazil
| | - R M S Isaias
- Departamento de Botânica, Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil
| | - M G C França
- Departamento de Botânica, Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil.
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18
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da Costa ACL, Rowland L, Oliveira RS, Oliveira AAR, Binks OJ, Salmon Y, Vasconcelos SS, Junior JAS, Ferreira LV, Poyatos R, Mencuccini M, Meir P. Stand dynamics modulate water cycling and mortality risk in droughted tropical forest. GLOBAL CHANGE BIOLOGY 2018; 24:249-258. [PMID: 28752626 DOI: 10.1111/gcb.13851] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/09/2017] [Indexed: 05/25/2023]
Abstract
Transpiration from the Amazon rainforest generates an essential water source at a global and local scale. However, changes in rainforest function with climate change can disrupt this process, causing significant reductions in precipitation across Amazonia, and potentially at a global scale. We report the only study of forest transpiration following a long-term (>10 year) experimental drought treatment in Amazonian forest. After 15 years of receiving half the normal rainfall, drought-related tree mortality caused total forest transpiration to decrease by 30%. However, the surviving droughted trees maintained or increased transpiration because of reduced competition for water and increased light availability, which is consistent with increased growth rates. Consequently, the amount of water supplied as rainfall reaching the soil and directly recycled as transpiration increased to 100%. This value was 25% greater than for adjacent nondroughted forest. If these drought conditions were accompanied by a modest increase in temperature (e.g., 1.5°C), water demand would exceed supply, making the forest more prone to increased tree mortality.
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Affiliation(s)
| | - Lucy Rowland
- Department of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | | | | | - Oliver J Binks
- Research School of Biology, Australian National University, Canberra, Australia
| | - Yann Salmon
- Department of Physics, University of Helsinki, Helsinki, Finland
| | | | - João A S Junior
- Instituto de Geosciências, Universidade Federal do Pará, Belém, Brasil
| | | | - Rafael Poyatos
- CREAF, Campus UAB, Cerdanyola del Vallés, Spain
- Laboratory of Plant Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | | | - Patrick Meir
- Research School of Biology, Australian National University, Canberra, Australia
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
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19
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Gotsch SG, Davidson K, Murray JG, Duarte VJ, Draguljić D. Vapor pressure deficit predicts epiphyte abundance across an elevational gradient in a tropical montane region. AMERICAN JOURNAL OF BOTANY 2017; 104:1790-1801. [PMID: 29196341 DOI: 10.3732/ajb.1700247] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 09/27/2017] [Indexed: 06/07/2023]
Abstract
PREMISE OF THE STUDY Tropical Montane Cloud Forests (TMCFs) are important ecosystems to study and preserve because of their high biodiversity and critical roles in local and regional ecosystem processes. TMCFs may be particularly affected by changes in climate because of the narrow bands of microclimate they occupy and the vulnerability of TMCF species to projected increases in cloud base heights and drought. A comprehensive understanding of the structure and function of TMCFs is lacking and difficult to attain because of variation in topography within and across TMCF sites. This causes large differences in microclimate and forest structure at both large and small scales. METHODS In this study, we estimated the abundance of the entire epiphyte community in the canopy (bryophytes, herbaceous vascular plants, woody epiphytes, and canopy dead organic matter) in six sites. In each of the sites we installed a complete canopy weather station to link epiphyte abundance to a number of microclimatic parameters. KEY RESULTS We found significant differences in epiphyte abundance across the sites; epiphyte abundance increased with elevation and leaf wetness, but decreased as vapor pressure deficit (VPD) increased. Epiphyte abundance had the strongest relationship with VPD; there were differences in VPD that could not be explained by elevation alone. CONCLUSIONS By measuring this proxy of canopy VPD, TMCF researchers will better understand differences in microclimate and plant community composition across TMCF sites. Incorporating such information in comparative studies will allow for more meaningful comparisons across TMCFs and will further conservation and management efforts in this ecosystem.
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Affiliation(s)
- Sybil G Gotsch
- Franklin and Marshall College, Department of Biology, Lancaster, Pennsylvania 17603 USA
| | - Kenneth Davidson
- Franklin and Marshall College, Department of Biology, Lancaster, Pennsylvania 17603 USA
| | - Jessica G Murray
- Franklin and Marshall College, Department of Biology, Lancaster, Pennsylvania 17603 USA
| | - Vanessa J Duarte
- Franklin and Marshall College, Department of Biology, Lancaster, Pennsylvania 17603 USA
| | - Danel Draguljić
- Franklin and Marshall College, Department of Mathematics, Lancaster, Pennsylvania 17603 USA
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Li J, Zhang J, Jin H, Wang YZ, Huang HY. Using UHPLC and UV-vis Fingerprint Method to Evaluate Substitutes for Swertia mileensis: An Endangered Medicinal Plant. Pharmacogn Mag 2017; 13:13-20. [PMID: 28216877 PMCID: PMC5307897 DOI: 10.4103/0973-1296.197655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 07/22/2016] [Accepted: 01/06/2017] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Millions of people are killed by viral hepatitis every year in the world, whereas many relevant medicines are too expensive to purchase. Swertia mileensis, a medicinal plant for hepatitis in the system of traditional Chinese medicine, has been vanishing gradually because of overexploitation. OBJECTIVE To find substitutes of S. mileensis and reduce the cost of purchasing drugs for hepatitis patients, the similarity of phytochemical constituents between S. mileensis and other three Swertia species was compared. MATERIALS AND METHODS Both ultra high performance liquid chromatographies and ultraviolet-vis fingerprints of four Swertia species were developed. Methanol extracts of the stems and leaves were used as samples to establish the fingerprint. The calibration curve was drawn for quantitative analysis of swertiamarin. The data of ultra high performance liquid chromatographies were evaluated statistically using similarity analysis and principal component analysis. RESULTS The result shows a significant difference at area of 204-290 nm in the ultraviolet fingerprint. Swertiamarin, the only one common peak, was defined in chromatographic fingerprints of four Swertia species. The quantitative analysis suggested that the highest concentration of swertiamarin is in S. davidii. The similarity indexes between different samples were almost under 0.60. In the principal component analysis, separate points not only represent the distinction among different species, but also perform chemical discrepancies in content between stems and leaves of one same species. CONCLUSIONS S. angustifolia, S. davidii, and S. punicea are not suitable as substitutes of S. mileensis because of their remarkable differences in entirety and local part. In order to address issues about substitutes and high cost of purchasing drugs, more studies need to undertake. SUMMARY The UHPLC fingerprint method indicated the significant difference on chemical ingredients in four plants from Swertia.Swertiamarin is the unique common compounds for four plants, which exist are in leaves of S. davidii with the highest content.The obvious diversity in four plants was displayed from comprehensive point of view though similarity assay and PCA analysis.The UV fingerprint method offsets the defect that the UHPLC fingerprint reflected messages of secoiridoid glycosides only. Abbreviation used: UHPLC: Ultra high performance liquid chromatography, UV-vis: Ultraviolet-vis, HBV: Anti-hepatitis virus, DNA: Deoxyribonucleic acid, PCA: Principal component analysis, D-GaIN: D-Galactosamine, BCG: Bacille Calmette-Guerin, LPS: Lipopolysaccharide.
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Affiliation(s)
- Jie Li
- College of Traditional Chinese Medicine, Yunnan University of Traditional Chinese Medicine, Kunming, China
- Institute of Medicine Plants, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Ji Zhang
- Institute of Medicine Plants, Yunnan Academy of Agricultural Sciences, Kunming, China
- Yunnan Technical Center for Quality of Chinese Materia Medica, Kunming, China
| | - Hang Jin
- College of Traditional Chinese Medicine, Yunnan University of Traditional Chinese Medicine, Kunming, China
- Institute of Medicine Plants, Yunnan Academy of Agricultural Sciences, Kunming, China
- Yunnan Technical Center for Quality of Chinese Materia Medica, Kunming, China
| | - Yuan-Zhong Wang
- Institute of Medicine Plants, Yunnan Academy of Agricultural Sciences, Kunming, China
- Yunnan Technical Center for Quality of Chinese Materia Medica, Kunming, China
| | - Heng-Yu Huang
- College of Traditional Chinese Medicine, Yunnan University of Traditional Chinese Medicine, Kunming, China
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Abstract
Abstract:Tropical montane cloud forests (TMCFs) are dynamic ecosystems defined by frequent, but intermittent, contact with fog. The resultant microclimate can vary considerably over short spatial and temporal scales, affecting the ecophysiology of TMCF plants. We synthesized research to date on TMCF carbon and water fluxes at the scale of the leaf, plant and ecosystem and then contextualized this synthesis with tropical lowland forest ecosystems. Mean light-saturated photosynthesis was lower than that of lowland forests, probably due to the effects of persistent reduced radiation leading to shade acclimation. Scaled to the ecosystem, measures of annual net primary productivity were also lower. Mean rates of transpiration, from the scale of the leaf to the ecosystem, were also lower than in lowland sites, likely due to lower atmospheric water demand, although there was considerable overlap in range. Lastly, although carbon use efficiency appears relatively invariant, limited evidence indicates that water use efficiency generally increases with altitude, perhaps due to increased cloudiness exerting a stronger effect on vapour pressure deficit than photosynthesis. The results reveal clear differences in carbon and water balance between TMCFs and their lowland counterparts and suggest many outstanding questions for understanding TMCF ecophysiology now and in the future.
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22
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Eller CB, Lima AL, Oliveira RS. Cloud forest trees with higher foliar water uptake capacity and anisohydric behavior are more vulnerable to drought and climate change. THE NEW PHYTOLOGIST 2016; 211:489-501. [PMID: 27038126 DOI: 10.1111/nph.13952] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 02/25/2016] [Indexed: 05/24/2023]
Abstract
Many tropical montane cloud forest (TMCF) trees are capable of foliar water uptake (FWU) during leaf-wetting events. In this study, we tested the hypothesis that maintenance of leaf turgor during periods of fog exposure and soil drought is related to species' FWU capacity. We conducted several experiments using apoplastic tracers, deuterium labeling and leaf immersion in water to evaluate differences in FWU among three common TMCF tree species. We also measured the effect of regular fog exposure on the leaf water potential of plants subjected to soil drought and used these data to model species' response to long-term drought. All species were able to absorb water through their leaf cuticles and/or trichomes, although the capacity to do so differed between species. During the drought experiment, the species with higher FWU capacity maintained leaf turgor for a longer period when exposed to fog, whereas the species with lower FWU exerted tighter stomatal regulation to maintain leaf turgor. Model results suggest that without fog, species with high FWU are more likely to lose turgor during seasonal droughts. We show that leaf-wetting events are essential for trees with high FWU, which tend to be more anisohydric, maintaining leaf turgor during seasonal droughts.
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Affiliation(s)
- Cleiton B Eller
- Department of Plant Biology, Institute of Biology, CP6109, University of Campinas - UNICAMP, Campinas, SP, 13083-970, Brazil
| | - Aline L Lima
- Center of Studies and Environmental Research - NEPAM, University of Campinas - UNICAMP, Campinas, SP, 13083-862, Brazil
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, CP6109, University of Campinas - UNICAMP, Campinas, SP, 13083-970, Brazil
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23
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Habitat moisture is an important driver of patterns of sap flow and water balance in tropical montane cloud forest epiphytes. Oecologia 2016; 182:357-71. [DOI: 10.1007/s00442-016-3659-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 05/13/2016] [Indexed: 11/25/2022]
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24
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Yan X, Zhou M, Dong X, Zou S, Xiao H, Ma XF. Molecular mechanisms of foliar water uptake in a desert tree. AOB PLANTS 2015; 7:plv129. [PMID: 26567212 PMCID: PMC4685171 DOI: 10.1093/aobpla/plv129] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 10/29/2015] [Indexed: 05/22/2023]
Abstract
Water deficits severely affect growth, particularly for the plants in arid and semiarid regions of the world. In addition to precipitation, other subsidiary water, such as dew, fog, clouds and small rain showers, may also be absorbed by leaves in a process known as foliar water uptake. With the severe scarcity of water in desert regions, this process is increasingly becoming a necessity. Studies have reported on physical and physiological processes of foliar water uptake. However, the molecular mechanisms remain less understood. As major channels for water regulation and transport, aquaporins (AQPs) are involved in this process. However, due to the regulatory complexity and functional diversity of AQPs, their molecular mechanism for foliar water uptake remains unclear. In this study, Tamarix ramosissima, a tree species widely distributed in desert regions, was investigated for gene expression patterns of AQPs and for sap flow velocity. Our results suggest that the foliar water uptake of T. ramosissima occurs in natural fields at night when the humidity is over a threshold of 85 %. The diurnal gene expression pattern of AQPs suggests that most AQP gene expressions display a circadian rhythm, and this could affect both photosynthesis and transpiration. At night, the PIP2-1 gene is also upregulated with increased relative air humidity. This gene expression pattern may allow desert plants to regulate foliar water uptake to adapt to extreme drought. This study suggests a molecular basis of foliar water uptake in desert plants.
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Affiliation(s)
- Xia Yan
- Key Laboratory of Inland River Ecohydrology, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, PR China Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions of Gansu Province, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, PR China
| | - Maoxian Zhou
- School of Agriculture and Forestry Economics and Management, Lanzhou University of Finance and Economics, Lanzhou 730020, PR China
| | - Xicun Dong
- Department of Radiobiology, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China
| | - Songbing Zou
- Key Laboratory of Inland River Ecohydrology, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, PR China
| | - Honglang Xiao
- Key Laboratory of Inland River Ecohydrology, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, PR China
| | - Xiao-Fei Ma
- Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions of Gansu Province, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, PR China
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Steppe K, Vandegehuchte MW, Tognetti R, Mencuccini M. Sap flow as a key trait in the understanding of plant hydraulic functioning. TREE PHYSIOLOGY 2015; 35:341-5. [PMID: 25926534 DOI: 10.1093/treephys/tpv033] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Affiliation(s)
- Kathy Steppe
- Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium;
| | - Maurits W Vandegehuchte
- Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium
| | - Roberto Tognetti
- Dipartimento di Bioscienze e Territorio, Universita' degli Studi del Molise, 86090 Pesche, Italy
| | - Maurizio Mencuccini
- School of GeoSciences, University of Edinburgh, Crew Building, West Mains Road, Edinburgh EH9 3JN, UK; ICREA at CREAF, Universidad Autonoma de Barcelona, Cerdanyola del Valles, Barcelona, Spain
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