1
|
Hesse BD, Hikino K, Gebhardt T, Buchhart C, Dervishi V, Goisser M, Pretzsch H, Häberle KH, Grams TEE. Acclimation of mature spruce and beech to five years of repeated summer drought - The role of stomatal conductance and leaf area adjustment for water use. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175805. [PMID: 39197757 DOI: 10.1016/j.scitotenv.2024.175805] [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: 06/12/2024] [Revised: 07/30/2024] [Accepted: 08/24/2024] [Indexed: 09/01/2024]
Abstract
Forests globally are experiencing severe droughts, leading to significant reductions in growth, crown dieback and even tree mortality. The ability of forest ecosystems to acclimate to prolonged and repeated droughts is critical for their survival with ongoing climate change. In a five-year throughfall exclusion experiment, we investigated the long-term physiological and morphological acclimation of mature Norway spruce (Picea abies [L.] KARST.) and European beech (Fagus sylvatica L.) to repeated summer drought at the leaf, shoot and whole tree level. Throughout the drought period, spruce reduced their total water use by 70 % to only 4-9 L per day and tree, while beech was less affected with about 30 % reduction of water use. During the first two summers, spruce achieved this by closing their stomata by up to 80 %. Additionally, from the second drought summer onwards, spruce produced shorter shoots and needles, resulting in a stepwise reduction of total leaf area of over 50 % by the end of the experiment. Surprisingly, no premature leaf loss was observed. This reduction in leaf area allowed a gradual increase in stomatal conductance. After the five-year drought experiment, water consumption per leaf area was the same as in the controls, while the total water consumption of spruce was still reduced. In contrast, beech showed no significant reduction in whole-tree leaf area, but nevertheless reduced water use by up to 50 % by stomatal closure. If the restriction of transpiration by stomatal closure is sufficient to ensure survival of Norway spruce during the first drought summers, then the slow but steady reduction in leaf area will ensure successful acclimation of water use, leading to reduced physiological drought stress and long-term survival. Neighboring beech appeared to benefit from the water-saving strategy of spruce by using the excess water.
Collapse
Affiliation(s)
- Benjamin D Hesse
- Technical University of Munich, School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany; University of Natural Resources and Life Sciences, Department of Integrative Biology and Biodiversity Research, Institute of Botany, Gregor-Mendel-Straße 33, 1180 Vienna, Austria.
| | - Kyohsuke Hikino
- Technical University of Munich, School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany; Swedish University of Agricultural Sciences (SLU), Department of Forest Ecology and Management, Umeå, Sweden
| | - Timo Gebhardt
- Technical University of Munich, School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany; Technical University of Munich, School of Life Sciences, Forest and Agroforest Systems, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany
| | - Claudia Buchhart
- Technical University of Munich, School of Life Sciences, Chair of Restoration Ecology, Emil-Ramann-Str. 6, 85354 Freising, Germany
| | - Vjosa Dervishi
- Technical University of Munich, School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany; Technical University of Munich, School of Life Sciences, Chair for Forest Growth and Yield Science, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany
| | - Michael Goisser
- Technical University of Munich, School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany
| | - Hans Pretzsch
- Technical University of Munich, School of Life Sciences, Chair for Forest Growth and Yield Science, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany
| | - Karl-Heinz Häberle
- Technical University of Munich, School of Life Sciences, Chair of Restoration Ecology, Emil-Ramann-Str. 6, 85354 Freising, Germany
| | - Thorsten E E Grams
- Technical University of Munich, School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Hans-Carl-von-Carlowitz Platz 2, 85354 Freising, Germany
| |
Collapse
|
2
|
Walthert L, Etzold S, Carminati A, Saurer M, Köchli R, Zweifel R. Coordination between degree of isohydricity and depth of root water uptake in temperate tree species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174346. [PMID: 38944298 DOI: 10.1016/j.scitotenv.2024.174346] [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: 02/21/2024] [Revised: 06/26/2024] [Accepted: 06/26/2024] [Indexed: 07/01/2024]
Abstract
In an increasingly dry environment, it is crucial to understand how tree species use soil water and cope with drought. However, there is still a knowledge gap regarding the relationships between species-specific stomatal behaviour, spatial root distribution, and root water uptake (RWU) dynamics. Our study aimed to investigate above- and below-ground aspects of water use during soil drying periods in four temperate tree species that differ in stomatal behaviour: two isohydric tracheid-bearing conifers, Scots pine and Norway spruce, and two more anisohydric deciduous species, the diffuse-porous European beech, and the ring-porous Downy oak. From 2015 to 2020, soil-tree-atmosphere-continuum parameters were measured for each species in monospecific forests where trees had no access to groundwater. The hourly time series included data on air temperature, vapor pressure deficit, soil water potential, soil hydraulic conductivity, and RWU to a depth of 2 m. Analysis of drought responses included data on stem radius, leaf water potential, estimated osmotically active compounds, and drought damage. Our study reveals an inherent coordination between stomatal regulation, fine root distribution and water uptake. Compared to conifers, the more anisohydric water use of oak and beech was associated with less strict stomatal closure, greater investment in deep roots, four times higher maximum RWU, a shift of RWU to deeper soil layers as the topsoil dried, and a more pronounced soil drying below 1 m depth. Soil hydraulic conductivity started to limit RWU when values fell below 10-3 to 10-5 cm/d, depending on the soil. As drought progressed, oak and beech may also have benefited from their leaf osmoregulatory capacity, but at the cost of xylem embolism with around 50 % loss of hydraulic conductivity when soil water potential dropped below -1.25 MPa. Consideration of species-specific water use is crucial for forest management and vegetation modelling to improve forest resilience to drought.
Collapse
Affiliation(s)
- Lorenz Walthert
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland.
| | - Sophia Etzold
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Andrea Carminati
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zürich, Universitätsstrasse 16, 8092 Zürich, Switzerland
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Roger Köchli
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| |
Collapse
|
3
|
Liu Z, Wang X, Jia G, Jiang J, Liao B. Introduction of broadleaf tree species can promote the resource use efficiency and gross primary productivity of pure forests. PLANT, CELL & ENVIRONMENT 2024. [PMID: 39177516 DOI: 10.1111/pce.15096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 08/24/2024]
Abstract
Long-term pure forest (PF) management and successive planting has result resulted in "low-efficiency artificial forests" in large areas. However, controversy persists over the promoting effect of introduction of broadleaf tree species on production efficiency of PF. This study hypothesised that introduced broadleaf tree species can significantly promote both water-nutrient use efficiency and gross primary productivity (GPP)of PF. Tree ring chronologies, water source, water use efficiency and GPP were analysed in coniferous Cunninghamia lanceolata and broadleaved Phoebe zhennan growing over the past three decades. The introduction of P. zhennan into C. lanceolata plantations resulted in inter-specific competition for water, probably because of the similarity of the main water source of these two tree species. However, C. lanceolata absorbed more water with a higher nutrient level from the 40-60-cm soil layer in mixed forests (MF). Although the co-existing tree species limited the basal area increment and growth rates of C. lanceolata in MF plots, the acquisition of dissolved nutrients from the fertile topsoil layer were enhanced; this increased the water use efficiency and GPP of MF plots. To achieve better ecological benefits and GPP, MFs should be constructed in southern China.
Collapse
Affiliation(s)
- Ziqiang Liu
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Xiaodi Wang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Guodong Jia
- Key Laboratory of Soil and Water Conservation and Desertification Combating of Ministry of Education, Beijing Forestry University, Beijing, China
| | - Jiang Jiang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Bin Liao
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, Hubei, China
| |
Collapse
|
4
|
Tan F, Cao W, Li X, Li Q. Characteristics, Relationships, and Anatomical Basis of Leaf Hydraulic Traits and Economic Traits in Temperate Desert Shrub Species. Life (Basel) 2024; 14:834. [PMID: 39063588 PMCID: PMC11278145 DOI: 10.3390/life14070834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 06/27/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024] Open
Abstract
Shrubs are a key component of desert ecosystems, playing a crucial role in controlling desertification and promoting revegetation, yet their growth is often impeded by drought. Leaf hydraulic traits and economic traits are both involved in the process of water exchange for carbon dioxide. Exploring the characteristics, relationships, and anatomical basis of these two suites of traits is crucial to understanding the mechanism of desert shrubs adapting to the desert arid environment. However, the relationship between these two sets of traits currently remains ambiguous. This study explored the leaf hydraulic, economic, and anatomical traits of 19 desert shrub species. The key findings include the following: Relatively larger LT values and smaller SLA values were observed in desert shrubs, aligning with the "slow strategy" in the leaf economics spectrum. The relatively high P50leaf, low HSMleaf, negative TLPleaf, and positive HSMtlp values indicated that severe embolism occurs in the leaves during the dry season, while most species were able to maintain normal leaf expansion. This implies a "tolerance" leaf hydraulic strategy in response to arid stress. No significant relationship was observed between P50leaf and Kmax, indicating the absence of a trade-off between hydraulic efficiency and embolism resistance. Certain coupling relationships were observed between leaf hydraulic traits and economic traits, both of which were closely tied to anatomical structures. Out of all of the leaf traits, LT was the central trait of the leaf traits network. The positive correlation between C content and WPleaf and HSMleaf, as well as the positive correlation between N content and HSMtlp, suggested that the cost of leaf construction was synergistic with hydraulic safety. The negative correlation between SLA, P content, GCL, and SAI suggested a functional synergistic relationship between water use efficiency and gas exchange rate. In summary, this research revealed that the coupling relationship between leaf hydraulic traits and economic traits was one of the important physiological and ecological mechanisms of desert shrubs for adapting to desert habitats.
Collapse
Affiliation(s)
| | | | | | - Qinghe Li
- State Key Laboratory of Efficient Production of Forest Resources, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China; (F.T.); (W.C.); (X.L.)
| |
Collapse
|
5
|
Waite PA, Kumar M, Link RM, Schuldt B. Coordinated hydraulic traits influence the two phases of time to hydraulic failure in five temperate tree species differing in stomatal stringency. TREE PHYSIOLOGY 2024; 44:tpae038. [PMID: 38606678 DOI: 10.1093/treephys/tpae038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 03/08/2024] [Accepted: 03/28/2024] [Indexed: 04/13/2024]
Abstract
Worldwide, forests are increasingly exposed to extreme droughts causing tree mortality. Because of the complex nature of the mechanisms involved, various traits have been linked to tree drought responses with contrasting results. This may be due to species-specific strategies in regulating water potential, a process that unfolds in two distinct phases: a first phase until stomatal closure, and a second phase until reaching lethal xylem hydraulic thresholds. We conducted dry-down experiments with five broadleaved temperate tree species differing in their degree of isohydry to estimate the time to stomatal closure (tsc) and subsequent time to critical hydraulic failure (tcrit). We measured various traits linked to tree drought responses, such as the water potentials at turgor loss point (Ptlp), stomatal closure (Pgs90), and 12%, 50% and 88% loss of xylem hydraulic conductance (P12, P50, P88), hydraulic capacitance (C), minimum leaf conductance (gmin), hydroscape area (HSA) and hydraulic safety margins (HSM). We found that Pgs90 followed previously recorded patterns of isohydry and was associated with HSA. Species ranked from more to less isohydric in the sequence Acer pseudoplatanus < Betula pendula < Tilia cordata < Sorbus aucuparia < Fagus sylvatica. Their degree of isohydry was associated with leaf safety (Ptlp and gmin), drought avoidance (C) and tsc, but decoupled from xylem safety (HSM and P88) and tcrit. Regardless of their stomatal stringency, species with wider HSM and lower P88 reached critical hydraulic failure later. We conclude that the duration of the first phase is determined by stomatal regulation, while the duration of the second phase is associated with xylem safety. Isohydry is thus linked to water use rather than to drought survival strategies, confirming the proposed use of HSA as a complement to HSM for describing plant drought responses before and after stomatal closure.
Collapse
Affiliation(s)
- Pierre-André Waite
- Julius-von-Sachs-Institute of Biological Sciences, Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Platz 3, 97082 Würzburg, Germany
- Forest Botany, TUD Dresden University of Technology, Pienner Straße 7, 01737, Tharandt, Germany
- CIRAD, UPR AIDA, 34398 Montpellier, France
| | - Manish Kumar
- Julius-von-Sachs-Institute of Biological Sciences, Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Platz 3, 97082 Würzburg, Germany
- ICAR - Central Soil Salinity Research Institute (CSSRI), Karnal, 132001, India
| | - Roman M Link
- Julius-von-Sachs-Institute of Biological Sciences, Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Platz 3, 97082 Würzburg, Germany
- Forest Botany, TUD Dresden University of Technology, Pienner Straße 7, 01737, Tharandt, Germany
| | - Bernhard Schuldt
- Julius-von-Sachs-Institute of Biological Sciences, Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Platz 3, 97082 Würzburg, Germany
- Forest Botany, TUD Dresden University of Technology, Pienner Straße 7, 01737, Tharandt, Germany
| |
Collapse
|
6
|
Paligi SS, Link RM, Isasa E, Bittencourt P, Cabral JS, Jansen S, Oliveira RS, Pereira L, Schuldt B. Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species. PLANT BIOLOGY (STUTTGART, GERMANY) 2023; 25:1171-1185. [PMID: 37703535 DOI: 10.1111/plb.13573] [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: 03/16/2023] [Accepted: 07/06/2023] [Indexed: 09/15/2023]
Abstract
The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.
Collapse
Affiliation(s)
- S S Paligi
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
| | - R M Link
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technische Universität Dresden, Tharandt, Germany
| | - E Isasa
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
| | - P Bittencourt
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - J S Cabral
- Ecosystem Modeling Group, Center for Computational and Theoretical Biology, University of Würzburg, Würzburg, Germany
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - S Jansen
- Institute of Botany, Ulm University, Ulm, Germany
| | - R S Oliveira
- Department of Plant Biology, Instituto de Biologia, University of Campinas, Campinas, SP, Brazil
| | - L Pereira
- Institute of Botany, Ulm University, Ulm, Germany
| | - B Schuldt
- Chair of Ecophysiology and Vegetation Ecology, Julius-von-Sachs Institute of Biological Sciences, University of Würzburg, Würzburg, Germany
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technische Universität Dresden, Tharandt, Germany
| |
Collapse
|
7
|
Qin J, Si J, Jia B, Zhao C, Zhou D, He X, Wang C, Zhu X. Water use strategies of Nitraria tangutorum in the lake-basin region of the Badain Jaran Desert. FRONTIERS IN PLANT SCIENCE 2023; 14:1240656. [PMID: 37649998 PMCID: PMC10465167 DOI: 10.3389/fpls.2023.1240656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 07/24/2023] [Indexed: 09/01/2023]
Abstract
Information regarding plant water-use strategies is essential for understanding the hydrological processes and plant survival adaptation mechanisms in desert lake basin regions. To examine the water use strategies of plants in desert lake basin areas, water uptake patterns, water use efficiency, and water potential of Nitraria tangutorum were investigated at different distances from the lake duringhe growing seasons in the lake basin regions of the Badain Jaran Desert. The results indicate that N. tangutorum primarily absorbed groundwater in May (63.8%) and August (53.5%), relied on deep soil water in June (75.1%), and uniformly absorbed soil water from different layers in July. These observations could be explained by periodic fluctuations in the groundwater level and the consequent decrease in soil water availability, as well as plant root adjustments. As soil water availability decreases, N. tangutorum adapts to water variation by increasing its water use efficiency (WUE) and reducing its leaf water potential (Ψ). With intensified water stress, N. tangutorum gradually shifted from adventurous anisohydric regulation to conservative isohydric regulation. Thus, N. tangutorum responds to diverse degrees of environmental changes by altering its water-use strategy. A better understanding of the adaptive water use strategies developed by desert plants under varying water availability conditions provides insight into the diversity of species' reactions to long-term drought and quantifies the hydrological cycle of desert ecosystems against the background of worldwide climate warming.
Collapse
Affiliation(s)
- Jie Qin
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jianhua Si
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Bing Jia
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chunyan Zhao
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Dongmeng Zhou
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaohui He
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chunlin Wang
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xinglin Zhu
- Key Laboratory of Eco-Hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
8
|
Petrík P, Petek-Petrik A, Mukarram M, Schuldt B, Lamarque LJ. Leaf physiological and morphological constraints of water-use efficiency in C 3 plants. AOB PLANTS 2023; 15:plad047. [PMID: 37560762 PMCID: PMC10407996 DOI: 10.1093/aobpla/plad047] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 07/05/2023] [Indexed: 08/11/2023]
Abstract
The increasing evaporative demand due to climate change will significantly affect the balance of carbon assimilation and water losses of plants worldwide. The development of crop varieties with improved water-use efficiency (WUE) will be critical for adapting agricultural strategies under predicted future climates. This review aims to summarize the most important leaf morpho-physiological constraints of WUE in C3 plants and identify gaps in knowledge. From the carbon gain side of the WUE, the discussed parameters are mesophyll conductance, carboxylation efficiency and respiratory losses. The traits and parameters affecting the waterside of WUE balance discussed in this review are stomatal size and density, stomatal control and residual water losses (cuticular and bark conductance), nocturnal conductance and leaf hydraulic conductance. In addition, we discussed the impact of leaf anatomy and crown architecture on both the carbon gain and water loss components of WUE. There are multiple possible targets for future development in understanding sources of WUE variability in plants. We identified residual water losses and respiratory carbon losses as the greatest knowledge gaps of whole-plant WUE assessments. Moreover, the impact of trichomes, leaf hydraulic conductance and canopy structure on plants' WUE is still not well understood. The development of a multi-trait approach is urgently needed for a better understanding of WUE dynamics and optimization.
Collapse
Affiliation(s)
- Peter Petrík
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research-Atmospheric Environmental Research (IMK-IFU), Kreuzeckbahnstraße 19, 82467 Garmisch-Partenkirchen, Germany
| | - Anja Petek-Petrik
- Institute of Botany, Czech Academy of Sciences, Lidická 971, 602 00 Brno, Czech Republic
| | - Mohammad Mukarram
- Department of Phytology, Faculty of Forestry, Technical University in Zvolen, T.G. Masaryka 24, 960 01 Zvolen, Slovakia
| | - Bernhard Schuldt
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technical University of Dresden (TUD), Pienner Str. 7, 01737 Tharandt, Germany
| | - Laurent J Lamarque
- Département des Sciences de l’environnement, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada
| |
Collapse
|
9
|
Schönauer M, Hietz P, Schuldt B, Rewald B. Root and branch hydraulic functioning and trait coordination across organs in drought-deciduous and evergreen tree species of a subtropical highland forest. FRONTIERS IN PLANT SCIENCE 2023; 14:1127292. [PMID: 37377798 PMCID: PMC10291250 DOI: 10.3389/fpls.2023.1127292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/26/2023] [Indexed: 06/29/2023]
Abstract
Vessel traits are key in understanding trees' hydraulic efficiency, and related characteristics like growth performance and drought tolerance. While most plant hydraulic studies have focused on aboveground organs, our understanding of root hydraulic functioning and trait coordination across organs remains limited. Furthermore, studies from seasonally dry (sub-)tropical ecosystems and mountain forests are virtually lacking and uncertainties remain regarding potentially different hydraulic strategies of plants differing in leaf habit. Here, we compared wood anatomical traits and specific hydraulic conductivities between coarse roots and small branches of five drought-deciduous and eight evergreen angiosperm tree species in a seasonally dry subtropical Afromontane forest in Ethiopia. We hypothesized that largest vessels and highest hydraulic conductivities are found in roots, with greater vessel tapering between roots and equally-sized branches in evergreen angiosperms due to their drought-tolerating strategy. We further hypothesized that the hydraulic efficiencies of root and branches cannot be predicted from wood density, but that wood densities across organs are generally related. Root-to-branch ratios of conduit diameters varied between 0.8 and 2.8, indicating considerable differences in tapering from coarse roots to small branches. While deciduous trees showed larger branch xylem vessels compared to evergreen angiosperms, root-to-branch ratios were highly variable within both leaf habit types, and evergreen species did not show a more pronounced degree of tapering. Empirically determined hydraulic conductivity and corresponding root-to-branch ratios were similar between both leaf habit types. Wood density of angiosperm roots was negatively related to hydraulic efficiency and vessel dimensions; weaker relationships were found in branches. Wood density of small branches was neither related to stem nor coarse root wood densities. We conclude that in seasonally dry subtropical forests, similar-sized coarse roots hold larger xylem vessels than small branches, but the degree of tapering from roots to branches is highly variable. Our results indicate that leaf habit does not necessarily influence the relationship between coarse root and branch hydraulic traits. However, larger conduits in branches and a low carbon investment in less dense wood may be a prerequisite for high growth rates of drought-deciduous trees during their shortened growing season. The correlation of stem and root wood densities with root hydraulic traits but not branch wood points toward large trade-offs in branch xylem towards mechanical properties.
Collapse
Affiliation(s)
- Marian Schönauer
- Department of Forest and Soil Sciences, Institute of Forest Ecology, University of Natural Resources and Life Sciences, Vienna, Austria
- Department of Forest Work Science and Engineering, Department of Forest Sciences and Forest Ecology, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Peter Hietz
- Department of Integrative Biology and Biodiversity Research, Institute of Botany, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
| | - Bernhard Schuldt
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Tharandt, Germany
| | - Boris Rewald
- Department of Forest and Soil Sciences, Institute of Forest Ecology, University of Natural Resources and Life Sciences, Vienna, Austria
| |
Collapse
|
10
|
Li Z, Wei S, Ge Y, Zhang Z, Li Z. Biomass-based materials for solar-powered seawater evaporation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:160003. [PMID: 36370772 DOI: 10.1016/j.scitotenv.2022.160003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/31/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
Clean and safe water is crucial to maintaining human life on earth. Solar-powered seawater desalination (SSD) is a promising and feasible way to use solar energy resources to overcome water scarcity. Among all the candidate materials for solar seawater evaporators, biomass-based materials stand out thanks to their excellent inherent natural structure, ease of preparation, low cost, and abundant resources. In this article, we review biomass-based materials, from angiosperms, algae, and fungi to animal materials and other atypical biomass materials, proposed for solar-powered seawater evaporation in the shape of the nanofluid, membrane, gels, composite sponge structures, composites Janus structures and other composites. The approaches for improving biomass-based solar seawater evaporators (BSSE) performance are emphasized, including optical absorption regulation, system thermal management optimization, adequate water supply, salt resistance, and effective steam condensate recovery. In the end, the opportunities and challenges of biomass-based materials for SSD are illustrated.
Collapse
Affiliation(s)
- Zichen Li
- School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University, 100 Daxuedong Road, Nanning 530004, China
| | - Shuxia Wei
- School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University, 100 Daxuedong Road, Nanning 530004, China
| | - Yuanyuan Ge
- School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University, 100 Daxuedong Road, Nanning 530004, China.
| | - Zheng Zhang
- School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University, 100 Daxuedong Road, Nanning 530004, China
| | - Zhili Li
- School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University, 100 Daxuedong Road, Nanning 530004, China.
| |
Collapse
|
11
|
Weithmann G, Schuldt B, Link RM, Heil D, Hoeber S, John H, Müller-Haubold H, Schüller LM, Schumann K, Leuschner C. Leaf trait modification in European beech trees in response to climatic and edaphic drought. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1272-1286. [PMID: 34854183 DOI: 10.1111/plb.13366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/07/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
Leaf morphological and physiological traits control the carbon and water relations of mature trees and are determinants of drought tolerance, but it is not well understood how they are modified in response to water deficits. We analysed five sun-canopy leaf traits (mean leaf size (LS), specific leaf area (SLA), Huber value (HV), water potential at turgor loss point (Ψtlp ) and foliar carbon isotope signature (δ13 C)) in European beech (Fagus sylvatica L.) across three precipitation gradients sampled in moist (2010), dry (2019) and very dry (2018) summers, and tested their response to short-term water deficits (climatic water balance (CWB) preceding sample collection) and long-term water availability (mean annual precipitation (MAP), plant-available soil water capacity (AWC) and neighbourhood competition). Across the 34 sites, LS varied seven-fold (3.9-27.0 cm2 ), SLA four-fold (77.1-306.9 cm²·g-1 ) and HV six-fold (1.0-6.65 cm2 ·m-2 ). In the 2018 dataset, LS showed a negative and HV a positive relationship to MAP, which contradicts relations found in multi-species samples. Average Ψtlp ranged from -1.90 to -2.62 MPa and decreased across the sites with decreasing CWB in the month prior to measurement, as well as with decreasing MAP and AWC in 2019. Studied leaf traits varied considerably between years, suggesting that mast fruiting and the severe 2018 drought caused the formation of smaller leaves. We conclude that sun-canopy leaf traits of European beech exhibit considerable plasticity in response to climatic and edaphic aridity, and that osmotic adjustment may be an important element in the drought response strategy of this anisohydric tree species.
Collapse
Affiliation(s)
- G Weithmann
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - B Schuldt
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - R M Link
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - D Heil
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - S Hoeber
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - H John
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - H Müller-Haubold
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - L-M Schüller
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - K Schumann
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - C Leuschner
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
- Centre for Biodiversity and Sustainable Land Use (CBL), University of Göttingen, Göttingen, Germany
| |
Collapse
|
12
|
Schuldt B, Ruehr NK. Responses of European forests to global change-type droughts. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1093-1097. [PMID: 36445187 DOI: 10.1111/plb.13484] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Affiliation(s)
- B Schuldt
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Dresden, Germany
| | - N K Ruehr
- Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, Germany
| |
Collapse
|
13
|
Guillén LA, Brzostek E, McNeil B, Raczka N, Casey B, Zegre N. Sap flow velocities of Acer saccharum and Quercus velutina during drought: Insights and implications from a throughfall exclusion experiment in West Virginia, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:158029. [PMID: 35973544 DOI: 10.1016/j.scitotenv.2022.158029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/10/2022] [Accepted: 08/10/2022] [Indexed: 06/15/2023]
Abstract
Forest species composition mediates evapotranspiration and the amount of water available to human-use downstream. In the last century, the heavily forested Appalachian region has been undergoing forest mesophication which is the progressive replacement of xeric species (e.g. black oak (Quercus velutina)) by mesic species (e.g. sugar maple (Acer saccharum)). Given differences between xeric and mesic species in water use efficiency and rainfall interception losses, investigating the consequences of these species shifts on water cycles is critical to improving predictions of ecosystem responses to climate change. To meet this need, we quantified the degree to which the sap velocities of two dominant broadleaved species (sugar maple and black oak) in West Virginia, responded to ambient and experimentally altered soil moisture conditions using a throughfall exclusion experiment. We then used these data to explore how predictions of future climate under two emissions scenarios could affect forest evapotranspiration rates. Overall, we found that the maples had higher sap velocity rates than the oaks. Sap velocity in maples showed a stronger sensitivity to vapor pressure deficit (VPD), particularly at high levels of VPD, than sap velocity in oaks. Experimentally induced reductions in shallow soil moisture did not have a relevant impact on sap velocity. In response to future climate scenarios of increased vapor pressure deficits in the Central Appalachian Mountains, our results highlight the different degrees to which two important tree species will increase transpiration, and potentially reduce the water available to the heavily populated areas downstream.
Collapse
Affiliation(s)
- Luis Andrés Guillén
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Science, Alnarp, Sweden; Department of Forestry & Natural Resources, West Virginia University, 334 Percival Hall, Morgantown, WV 26506, USA.
| | | | - Brenden McNeil
- Department of Geology and Geography, West Virginia University, USA
| | | | - Brittany Casey
- Department of Geology and Geography, West Virginia University, USA
| | - Nicolas Zegre
- Forestry & Natural Resources, West Virginia University, USA
| |
Collapse
|
14
|
Tree species matter for forest microclimate regulation during the drought year 2018: disentangling environmental drivers and biotic drivers. Sci Rep 2022; 12:17559. [PMID: 36266469 PMCID: PMC9584904 DOI: 10.1038/s41598-022-22582-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 10/17/2022] [Indexed: 01/13/2023] Open
Abstract
Tree canopies are considered to effectively buffer climate extremes and to mitigate climate change effects. Droughts, which are predicted to become more frequent in the course of climate change, might alter the microclimatic cooling potential of trees. However, our understanding of how microclimate at the tree canopy level is modulated by environmental and tree characteristics and their interactions is still limited. Here, we investigated canopy temperature regulation for five mature co-occurring tree species for two contrasting hydrological situations during the severe drought in 2018. Even though we observed a significant drought-induced decline in canopy cover and transpiration across tree species, we found evidence that differences in the water use strategies of trees affected cooling mechanisms differently. Although a large share of the variations in the cooling potential of trees was explained by direct and indirect effects of meteorological factors, we identified a gradual shift in importance from latent heat flux to components defining the magnitude of sensible heat flux on the energy budget of tree as the drought gained severity. The decrease in latent heat fluxes, approximated by sap flow rates, furthermore resulted in a reduced cooling potential and an equalization of tree species canopy temperatures.
Collapse
|
15
|
Chen Z, Li S, Wan X, Liu S. Strategies of tree species to adapt to drought from leaf stomatal regulation and stem embolism resistance to root properties. FRONTIERS IN PLANT SCIENCE 2022; 13:926535. [PMID: 36237513 PMCID: PMC9552884 DOI: 10.3389/fpls.2022.926535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
Considerable evidences highlight the occurrence of increasing widespread tree mortality as a result of global climate change-associated droughts. However, knowledge about the mechanisms underlying divergent strategies of various tree species to adapt to drought has remained remarkably insufficient. Leaf stomatal regulation and embolism resistance of stem xylem serves as two important strategies for tree species to prevent hydraulic failure and carbon starvation, as comprising interconnected physiological mechanisms underlying drought-induced tree mortality. Hence, the physiological and anatomical determinants of leaf stomatal regulation and stems xylem embolism resistance are evaluated and discussed. In addition, root properties related to drought tolerance are also reviewed. Species with greater investment in leaves and stems tend to maintain stomatal opening and resist stem embolism under drought conditions. The coordination between stomatal regulation and stem embolism resistance are summarized and discussed. Previous studies showed that hydraulic safety margin (HSM, the difference between minimum water potential and that causing xylem dysfunction) is a significant predictor of tree species mortality under drought conditions. Compared with HSM, stomatal safety margin (the difference between water potential at stomatal closure and that causing xylem dysfunction) more directly merge stomatal regulation strategies with xylem hydraulic strategies, illustrating a comprehensive framework to characterize plant response to drought. A combination of plant traits reflecting species' response and adaptation to drought should be established in the future, and we propose four specific urgent issues as future research priorities.
Collapse
Affiliation(s)
- Zhicheng Chen
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Shan Li
- Department of Environmental Science and Ecology, School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Xianchong Wan
- Institute of Ecological Conservation and Restoration, Chinese Academy of Forestry, Beijing, China
| | - Shirong Liu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| |
Collapse
|
16
|
Influence of Juvenile Growth on Xylem Safety and Efficiency in Three Temperate Tree Species. FORESTS 2022. [DOI: 10.3390/f13060909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The evolution of the internal water transport system was a prerequisite for high plant productivity. In times of climate change, understanding the dependency of juvenile growth on xylem hydraulic physiology is therefore of high importance. Here, we explored various wood anatomical, hydraulic, and leaf morphological traits related to hydraulic safety and efficiency in three temperate broadleaved tree species (Acer pseudoplatanus, Betula pendula, and Sorbus aucuparia). We took advantage of a severe natural heat wave that resulted in different climatic growing conditions for even-aged plants from the same seed source growing inside a greenhouse and outside. Inside the greenhouse, the daily maximum vapour pressure deficit was on average 36% higher than outside during the growing seasons. Because of the higher atmospheric moisture stress, the biomass production differed up to 5.6-fold between both groups. Except for one species, a high productivity was associated with a high hydraulic efficiency caused by large xylem vessels and a large, supported leaf area. Although no safety-efficiency trade-off was observed, productivity was significantly related to P50 in two of the tree species but without revealing any clear pattern. A considerable plasticity in given traits was observed between both groups, with safety-related traits being more static while efficiency-related traits revealed a higher intra-specific plasticity. This was associated with other wood anatomical and leaf morphological adjustments. We confirm that a high hydraulic efficiency seems to be a prerequisite for a high biomass production, while our controversial results on the growth–xylem safety relationship confirm that safety-efficiency traits are decoupled and that their relationship with juvenile growth and water regime is species-specific.
Collapse
|
17
|
Hajek P, Link RM, Nock CA, Bauhus J, Gebauer T, Gessler A, Kovach K, Messier C, Paquette A, Saurer M, Scherer-Lorenzen M, Rose L, Schuldt B. Mutually inclusive mechanisms of drought-induced tree mortality. GLOBAL CHANGE BIOLOGY 2022; 28:3365-3378. [PMID: 35246895 DOI: 10.1111/gcb.16146] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
Unprecedented tree dieback across Central Europe caused by recent global change-type drought events highlights the need for a better mechanistic understanding of drought-induced tree mortality. Although numerous physiological risk factors have been identified, the importance of two principal mechanisms, hydraulic failure and carbon starvation, is still debated. It further remains largely unresolved how the local neighborhood composition affects individual mortality risk. We studied 9435 young trees of 12 temperate species planted in a diversity experiment in 2013 to assess how hydraulic traits, carbon dynamics, pest infestation, tree height and neighborhood competition influence individual mortality risk. Following the most extreme global change-type drought since record in 2018, one third of these trees died. Across species, hydraulic safety margins (HSMs) were negatively and a shift towards a higher sugar fraction in the non-structural carbohydrate (NSC) pool positively associated with mortality risk. Moreover, trees infested by bark beetles had a higher mortality risk, and taller trees a lower mortality risk. Most neighborhood interactions were beneficial, although neighborhood effects were highly species-specific. Species that suffered more from drought, especially Larix spp. and Betula spp., tended to increase the survival probability of their neighbors and vice versa. While severe tissue dehydration marks the final stage of drought-induced tree mortality, we show that hydraulic failure is interrelated with a series of other, mutually inclusive processes. These include shifts in NSC pools driven by osmotic adjustment and/or starch depletion as well as pest infestation and are modulated by the size and species identity of a tree and its neighbors. A more holistic view that accounts for multiple causes of drought-induced tree mortality is required to improve predictions of trends in global forest dynamics and to identify mutually beneficial species combinations.
Collapse
Affiliation(s)
- Peter Hajek
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Roman M Link
- Chair of Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Institute of Biological Sciences, Würzburg, Germany
| | - Charles A Nock
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Jürgen Bauhus
- Chair of Silviculture, University of Freiburg, Freiburg, Germany
| | - Tobias Gebauer
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- ETH Zurich, Institute of Terrestrial Ecosystems, Zurich, Switzerland
| | - Kyle Kovach
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Christian Messier
- Center for Forest Research, Université du Québec à Montréal, Montréal, Quebec, Canada
- University of Quebec in Outaouais (UQO), Institut des Sciences de la Forêt Tempérée (ISFORT), Gatineau, Quebec, Canada
| | - Alain Paquette
- Center for Forest Research, Université du Québec à Montréal, Montréal, Quebec, Canada
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
| | | | - Laura Rose
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Bernhard Schuldt
- Chair of Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Institute of Biological Sciences, Würzburg, Germany
| |
Collapse
|
18
|
Leuschner C, Schipka F, Backes K. Stomatal regulation and water potential variation in European beech: challenging the iso/anisohydry concept. TREE PHYSIOLOGY 2022; 42:365-378. [PMID: 34415347 DOI: 10.1093/treephys/tpab104] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
The iso/anisohydric continuum has been used to classify tree species' drought response strategies. The range over which stomata are regulating leaf water potential (ψl) before turgor loss occurs can be described with metrics such as the dependence of ψl on soil water potential (ψsoil) and the size of 'hydroscape area' (HA), but corresponding field data from adult trees are scarce. We examined the stomatal conductance (gs)-ψl relationship in its temporal (diurnal vs seasonal and interannual) and spatial (within-crown vs between-site) variation in European beech, using extensive ψl and gs measurements in the canopy of four beech stands across a precipitation gradient, and complemented the data set by published ψl and gs measurements in further Central European beech stands (including the extreme 2018 drought) in order to cover the full water potential operation space of the species. Both metrics characterize beech as a strictly anisohydric species with δψl/δψsoil >> 1 and HA = 4 MPa2. However, stomates close sensitively in response to increasing vapor pressure deficit, disproving the widely assumed dependence of large ψl variation on looser stomatal control. Characterizing the water status regulation mechanisms of trees requires separating diurnal from day-to-day variation in ψl and gs. The large diurnal and seasonal ψl variation in beech leaves is partly caused by a low leaf tissue elasticity, suggesting that a whole-plant perspective with consideration of osmotic and elastic tissue properties and stem and root hydraulics is needed for fully understanding ψl regulation and the drought tolerance strategy of trees.
Collapse
Affiliation(s)
| | - Florian Schipka
- Plant Ecology, University of Goettingen, 37073 Göttingen, Germany
| | - Katharina Backes
- Plant Ecology, University of Goettingen, 37073 Göttingen, Germany
| |
Collapse
|
19
|
Cao J, Liu H, Zhao B, Li Z, Liang B, Shi L, Wu L, Cressey EL, Quine TA. High forest stand density exacerbates growth decline of conifers driven by warming but not broad-leaved trees in temperate mixed forest in northeast Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 795:148875. [PMID: 34247087 DOI: 10.1016/j.scitotenv.2021.148875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Increasing temperature over recent decades is expected to positively impact tree growth in humid regions. However, high stand density could increase the negative effects of warming-induced drought through inter-tree competition. How neighborhood competition impacts tree growth responding to climate change remains unclear. Here, we utilized the Changbai Mountain region in northeastern Asia as our study area. We quantified individual tree growth using tree-ring samples collected from three dominant tree species growing in three forest stand density levels. We estimated the effects of climate warming and forest stand density on growth processes and tested for a species-specific response to climate. Our results demonstrated that overall 25% of Korean pine, but only ~3% of Mongolian oak and ~ 4% of Manchurian ash experienced growth reduction. Increased forest density can also exacerbate growth reduction. We identified a climate turning point in 1984, where warming rapidly increased, and defined two groups, "enhance group" (EG) and "decline group" (DG), according to the individual tree growth trend after 1984. For the EG, climate warming increased temperature sensitivity, but the temperature sensitivity declined with increasing stand density for the whole study period. For the DG, tree growth sensitivity shifted from temperature to precipitation after 1984, driven by increased competition pressure under climate warming. Our study concludes that growth decline from warming-induced drought might be amplified by high forest stand density, was especially pronounced in conifer trees.
Collapse
Affiliation(s)
- Jing Cao
- College of Urban and Environmental Science, MOE Laboratory for Earth Surface Processes, Peking University, Beijing, China
| | - Hongyan Liu
- College of Urban and Environmental Science, MOE Laboratory for Earth Surface Processes, Peking University, Beijing, China.
| | - Bo Zhao
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Zongshan Li
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing, China
| | - Boyi Liang
- College of Urban and Environmental Science, MOE Laboratory for Earth Surface Processes, Peking University, Beijing, China; Geography, College of Life & Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
| | - Liang Shi
- College of Urban and Environmental Science, MOE Laboratory for Earth Surface Processes, Peking University, Beijing, China
| | - Lu Wu
- College of Urban and Environmental Science, MOE Laboratory for Earth Surface Processes, Peking University, Beijing, China
| | - Elizabeth L Cressey
- Geography, College of Life & Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
| | - Timothy A Quine
- Geography, College of Life & Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
| |
Collapse
|
20
|
Marchand W, Girardin MP, Hartmann H, Lévesque M, Gauthier S, Bergeron Y. Contrasting life-history traits of black spruce and jack pine influence their physiological response to drought and growth recovery in northeastern boreal Canada. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148514. [PMID: 34218146 DOI: 10.1016/j.scitotenv.2021.148514] [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: 04/14/2021] [Revised: 06/09/2021] [Accepted: 06/14/2021] [Indexed: 06/13/2023]
Abstract
An increase in frequency, intensity and duration of drought events affects forested ecosystems. Trees react to these changes by adjusting stomatal conductance to maximize the trade-off between carbon gains and water losses. A better understanding of the consequences of these drought-induced physiological adjustments for tree growth could help inferring future productivity potentials of boreal forests. Here, we used samples from a forest inventory network in Canada where a decline in growth rates of black spruce (Picea mariana (Mill.) B.S.P.) and jack pine (Pinus banksiana Lamb.) occurred in 1988-1992, an exceptionally dry period, to verify if this growth decline resulted from physiological adjustments of trees to drought. We measured carbon and oxygen isotope ratios in growth rings of 95 spruces and 49 pines spanning 1985-1993. We used 13C discrimination (Δ13C) and 18O enrichment (Δ18O) as proxies for intrinsic water use efficiency and stomatal conductance, respectively. We studied how inter-annual variability in isotopic signals was linked to climate moisture index, vapor pressure deficit and annual snowfall amount. We found significantly lower Δ13C values over 1988-1990, and significantly higher Δ18O values in 1988-1989 and 1991 compared to the 1985-1993 averages. We also observed that a low climatic water balance and a high vapor pressure deficit were linked with low Δ13C and high Δ18O in the two study species, in parallel with low growth rates. The latter effect persisted into the year following drought for black spruce, but not for jack pine. These findings highlight that small differences in physiological parameters between species could translate into large differences in post-drought recovery. The stronger and longer lasting impact on black spruce compared to jack pine suggests a less efficient carbon use and a lower acclimation potential to future warmer and drier climate conditions.
Collapse
Affiliation(s)
- William Marchand
- Centre d'étude de la forêt, Université du Québec à Montréal, C.P. 8888, succ. Centre-ville, Montréal, QC H3C 3P8, Canada; Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6 - Suchdol 165 00, Czech Republic; Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, 1055 du P.E.P.S, P.O. Box 10380, Stn. Sainte-Foy, Québec, QC G1V 4C7, Canada.
| | - Martin P Girardin
- Centre d'étude de la forêt, Université du Québec à Montréal, C.P. 8888, succ. Centre-ville, Montréal, QC H3C 3P8, Canada; Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, 1055 du P.E.P.S, P.O. Box 10380, Stn. Sainte-Foy, Québec, QC G1V 4C7, Canada
| | - Henrik Hartmann
- Max-Planck Institute for Biogeochemistry, Department of Biogeochemical Processes, Hans-Knöll Str. 10, 07745 Jena, Germany
| | - Mathieu Lévesque
- Forest Management/Silviculture Group, Institute of Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, 8092 Zurich, Switzerland
| | - Sylvie Gauthier
- Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, 1055 du P.E.P.S, P.O. Box 10380, Stn. Sainte-Foy, Québec, QC G1V 4C7, Canada; Centre d'étude de la forêt, Université du Québec à Montréal, C.P. 8888, succ. Centre-ville, Montréal, QC H3C 3P8, Canada
| | - Yves Bergeron
- Centre d'étude de la forêt, Université du Québec à Montréal, C.P. 8888, succ. Centre-ville, Montréal, QC H3C 3P8, Canada; Institut de recherche sur les forêts, Université du Québec en Abitibi-Témiscamingue, 445 boul. de l'Université, Rouyn-Noranda, QC J9X 5E4, Canada
| |
Collapse
|
21
|
Isohydricity of Two Different Citrus Species under Deficit Irrigation and Reclaimed Water Conditions. PLANTS 2021; 10:plants10102121. [PMID: 34685931 PMCID: PMC8538605 DOI: 10.3390/plants10102121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/27/2021] [Accepted: 09/29/2021] [Indexed: 01/07/2023]
Abstract
Citrus species are frequently subjected to water and saline stresses worldwide. We evaluated the effects of diurnal changes in the evaporative demands and soil water contents on the plant physiology of grapefruit and mandarin crops under saline reclaimed (RW) and transfer (TW) water conditions, combined with two irrigation strategies, fully irrigated (fI) and non-irrigated (nI). The physiological responses were different depending on the species. Grapefruit showed an isohydric pattern, which restricted the use of the leaf water potential (Ψl) as a plant water status indicator. Its water status was affected by salinity (RW) and water stress (nI), mainly as the combination of both stresses (RW-nI); however, mandarin turned out to be relatively more tolerant to salinity and more sensitive to water stress, mainly because of its low hydraulic conductance (K) levels, showing a critical drop in Ψl that led to severe losses of root–stem (Kroot–stem) and canopy (Kcanopy) hydraulic conductance in TW-nI. This behavior was not observed in RW-nI because a reduction in canopy volume as an adaptive characteristic was observed; thus, mandarin exhibited more anisohydric behavior compared to grapefruit, but isohydrodynamic since its hydrodynamic water potential gradient from roots to shoots (ΔΨplant) was relatively constant across variations in stomatal conductance (gs) and soil water potential. The gs was considered a good plant water status indicator for irrigation scheduling purposes in both species, and its responses to diurnal VPD rise and soil drought were strongly correlated with Kroot–stem. ABA did not show any effect on stomatal regulation, highlighting the fundamental role of plant hydraulics in driving stomatal closure.
Collapse
|
22
|
Fuchs S, Leuschner C, Mathias Link R, Schuldt B. Hydraulic variability of three temperate broadleaf tree species along a water availability gradient in central Europe. THE NEW PHYTOLOGIST 2021; 231:1387-1400. [PMID: 33964029 DOI: 10.1111/nph.17448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 05/01/2021] [Indexed: 06/12/2023]
Abstract
Plant hydraulic traits are key for understanding and predicting tree drought responses. Information about the degree of the traits' intra-specific variability may guide the selection of drought-resistant genotypes and is crucial for trait-based modelling approaches. For the three temperate minor broadleaf tree species Acer platanoides, Carpinus betulus and Tilia cordata, we measured xylem embolism resistance (P50 ), leaf turgor loss point (PTLP ), specific hydraulic conductivity (KS ), Huber values (HVs), and hydraulic safety margins in adult trees across a precipitation gradient. We further quantified trait variability on different organizational levels (inter-specific to within-canopy variation), and analysed its relationship to climatic and soil water availability. Although we observed a certain intra-specific trait variability (ITV) in safety-related traits (P50 , PTLP ) with higher within-tree and between-tree than between populations variability, the magnitude was small compared to inter-specific differences, which explained 78.4% and 58.3% of the variance in P50 and PTLP , respectively. In contrast, efficiency-related traits (KS , HV) showed a high ITV both within populations and within the crowns of single trees. Surprisingly, the observed ITV of all traits was neither driven by climatic nor soil water availability. In conclusion, the high degree of conservatism in safety-related traits highlights their potential for trait-based modelling approaches.
Collapse
Affiliation(s)
- Sebastian Fuchs
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
| | - Christoph Leuschner
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
- Centre for Biodiversity and Sustainable Land Use (CBL), University of Goettingen, Goettingen, 37075, Germany
| | - Roman Mathias Link
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
| | - Bernhard Schuldt
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
| |
Collapse
|