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Mašek J, Dorado-Liñán I, Treml V. Responses of stem growth and canopy greenness of temperate conifers to dry spells. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2024; 68:1533-1544. [PMID: 38630139 PMCID: PMC11281975 DOI: 10.1007/s00484-024-02682-w] [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: 12/12/2023] [Revised: 04/02/2024] [Accepted: 04/11/2024] [Indexed: 07/28/2024]
Abstract
Dry spells strongly influence biomass production in forest ecosystems. Their effects may last several years following a drought event, prolonging growth reduction and therefore restricting carbon sequestration. Yet, our understanding of the impact of dry spells on the vitality of trees' above-ground biomass components (e.g., stems and leaves) at a landscape level remains limited. We analyzed the responses of Pinus sylvestris and Picea abies to the four most severe drought years in topographically complex sites. To represent stem growth and canopy greenness, we used chronologies of tree-ring width and time series of the Normalized Difference Vegetation Index (NDVI). We analyzed the responses of radial tree growth and NDVI to dry spells using superposed epoch analysis and further explored this relationship using mixed-effect models. Our results show a stronger and more persistent response of radial growth to dry spells and faster recovery of canopy greenness. Canopy greenness started to recover the year after the dry spell, whereas radial tree growth remained reduced for the two subsequent years and did not recover the pre-drought level until the fourth year after the event. Stem growth and canopy greenness were influenced by climatic conditions during and after drought events, while the effect of topography was marginal. The opposite responses of stem growth and canopy greenness following drought events suggest a different impact of dry spells on trees´ sink and source compartments. These results underscore the crucial importance of understanding the complexities of tree growth as a major sink of atmospheric carbon.
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Affiliation(s)
- Jiří Mašek
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43, Prague, Czech Republic.
| | - Isabel Dorado-Liñán
- Dpto. de Sistemas y Recursos Naturales, Universidad Politécnica de Madrid, Madrid, Spain
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43, Prague, Czech Republic
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2
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Kašpar J, Krůček M, Král K. The effects of solar radiation on daily and seasonal stem increment of canopy trees in European temperate old-growth forests. THE NEW PHYTOLOGIST 2024; 243:662-673. [PMID: 38769735 DOI: 10.1111/nph.19852] [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: 11/29/2023] [Accepted: 05/05/2024] [Indexed: 05/22/2024]
Abstract
It is well established that solar irradiance greatly influences tree metabolism and growth through photosynthesis, but its effects acting through individual climate metrics have not yet been well quantified. Understanding these effects is crucial for assessing the impacts of climate change on forest ecosystems. To describe the effects of solar irradiance on tree growth, we installed 110 automatic dendrometers in two old-growth mountain forest reserves in Central Europe, performed detailed terrestrial and aerial laser scanning to obtain precise tree profiles, and used these to simulate the sum of solar irradiance received by each tree on a daily basis. Generalized linear mixed-effect models were applied to simulate the probability of growth and the growth intensity over seven growing seasons. Our results demonstrated various contrasting effects of solar irradiance on the growth of canopy trees. On the one hand, the highest daily growth rates corresponded with the highest solar irradiance potentials (i.e. the longest photoperiod). Intense solar irradiance significantly decreased tree growth, through an increase in the vapor pressure deficit. These effects were consistent for all species but had different magnitude. Tree growth is the most effective on long rainy/cloudy days with low solar irradiance.
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Affiliation(s)
- Jakub Kašpar
- Department of Forest Ecology, The Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Lidická 25-27, 602 00, Brno, Czech Republic
| | - Martin Krůček
- Department of Forest Ecology, The Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Lidická 25-27, 602 00, Brno, Czech Republic
| | - Kamil Král
- Department of Forest Ecology, The Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Lidická 25-27, 602 00, Brno, Czech Republic
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3
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Li Y, Hoch G. The sensitivity of root water uptake to cold root temperature follows species-specific upper elevational distribution limits of temperate tree species. PLANT, CELL & ENVIRONMENT 2024; 47:2192-2205. [PMID: 38481108 DOI: 10.1111/pce.14874] [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: 11/16/2023] [Revised: 02/21/2024] [Accepted: 02/24/2024] [Indexed: 04/30/2024]
Abstract
Physiological water stress induced by low root temperatures might contribute to species-specific climatic limits of tree distribution. We investigated the low temperature sensitivity of root water uptake and transport in seedlings of 16 European tree species which reach their natural upper elevation distribution limits at different distances to the alpine treeline. We used 2H-H2O pulse-labelling to quantify the water uptake and transport velocity from roots to leaves in seedlings exposed to constant 15°C, 7°C or 2°C root temperature, but identical aboveground temperatures between 20°C and 25°C. In all species, low root temperatures reduced the water transport rate, accompanied by reduced stem water potentials and stomatal conductance. At 7°C root temperature, the relative water uptake rates among species correlated positively with the species-specific upper elevation limits, indicating an increasingly higher sensitivity to lower root zone temperatures, the lower a species' natural elevational distribution limit. Conversely, 2°C root temperature severely inhibited water uptake in all species, irrespective of the species' thermal elevational limits. We conclude that low temperature-induced hydraulic constraints contribute to the cold distribution limits of temperate tree species and are a potential physiological cause behind the low temperature limits of plant growth in general.
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Affiliation(s)
- Yating Li
- Department of Environmental Sciences-Botany, University of Basel, Basel, Switzerland
| | - Günter Hoch
- Department of Environmental Sciences-Botany, University of Basel, Basel, Switzerland
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4
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Tian Q, He Z, Xiao S, Peng X, Lin P, Zhu X, Feng X. Intra-annual stem radial growth of Qinghai spruce and its environmental drivers in the Qilian Mountains, northwestern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 915:170093. [PMID: 38224885 DOI: 10.1016/j.scitotenv.2024.170093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 12/06/2023] [Accepted: 01/09/2024] [Indexed: 01/17/2024]
Abstract
Tree stem radial growth could be used to estimate forest productivity, which plays a dominant role in the carbon sink of terrestrial ecosystems. However, it is still obscure how intra-annual stem radial growth is regulated by environmental variables. Here, we monitored Qinghai spruce stem radial growth over seven years and analyzed the environmental drivers of the intra-annual stem radial changes in the Qilian Mountains at low (2700 m) and high altitudes (3200 m). We found that stem radial growth initiated when the daily mean minimum air temperature reached 1.6oC, while the cessation of stem growth was unrelated to temperatures and water conditions. Initiations of stem growth at 2700 m were significantly earlier than that at 3200 m. Maximum growth rates were observed before the summer solstice at low altitude, whereas at high altitude, the majority of them occurred after the summer solstice. Most variability in annual stem increment (AI) can be explained by the rate (Rm) than by the duration of stem growth (∆t), and 78.9 % and 69.6 % of the variability in AI were attributable to Rm for the lower and upper site, respectively. Structural equation modeling revealed that precipitation (P) could both directly positively influence stem radial increment (SRI) and indirectly positively influence SRI through influencing relative humidity (RH), but the positive effect of P on SRI was higher at low altitude than at high altitude. Daily minimum air temperature (Tmin) was also the main direct diver of SRI, and the positive effect of Tmin on SRI was higher at high altitude than at low altitude. Considering the trends in climate warming and humidification over the past decades, climate changes would result in earlier initiation of Qinghai spruce stem growth and promote the growth through positive response to increased precipitation in low altitude and through elevated temperature in high altitude, respectively.
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Affiliation(s)
- Quanyan Tian
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China
| | - Zhibin He
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China.
| | - Shengchun Xiao
- Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China; Key Laboratory of Eco-hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Xiaomei Peng
- Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China; Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Pengfei Lin
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China
| | - Xi Zhu
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China
| | - Xiangyan Feng
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, China; University of Chinese Academy of Sciences, Beijing 100049, China
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5
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Vitali V, Schuler P, Holloway-Phillips M, D'Odorico P, Guidi C, Klesse S, Lehmann MM, Meusburger K, Schaub M, Zweifel R, Gessler A, Saurer M. Finding balance: Tree-ring isotopes differentiate between acclimation and stress-induced imbalance in a long-term irrigation experiment. GLOBAL CHANGE BIOLOGY 2024; 30:e17237. [PMID: 38488024 DOI: 10.1111/gcb.17237] [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: 10/20/2023] [Revised: 02/05/2024] [Accepted: 02/09/2024] [Indexed: 03/19/2024]
Abstract
Scots pine (Pinus sylvestris L.) is a common European tree species, and understanding its acclimation to the rapidly changing climate through physiological, biochemical or structural adjustments is vital for predicting future growth. We investigated a long-term irrigation experiment at a naturally dry forest in Switzerland, comparing Scots pine trees that have been continuously irrigated for 17 years (irrigated) with those for which irrigation was interrupted after 10 years (stop) and non-irrigated trees (control), using tree growth, xylogenesis, wood anatomy, and carbon, oxygen and hydrogen stable isotope measurements in the water, sugars and cellulose of plant tissues. The dendrochronological analyses highlighted three distinct acclimation phases to the treatments: irrigated trees experienced (i) a significant growth increase in the first 4 years of treatment, (ii) high growth rates but with a declining trend in the following 8 years and finally (iii) a regression to pre-irrigation growth rates, suggesting the development of a new growth limitation (i.e. acclimation). The introduction of the stop treatment resulted in further growth reductions to below-control levels during the third phase. Irrigated trees showed longer growth periods and lower tree-ring δ13 C values, reflecting lower stomatal restrictions than control trees. Their strong tree-ring δ18 O and δ2 H (O-H) relationship reflected the hydrological signature similarly to the control. On the contrary, the stop trees had lower growth rates, conservative wood anatomical traits, and a weak O-H relationship, indicating a physiological imbalance. Tree vitality (identified by crown transparency) significantly modulated growth, wood anatomical traits and tree-ring δ13 C, with low-vitality trees of all treatments performing similarly regardless of water availability. We thus provide quantitative indicators for assessing physiological imbalance and tree acclimation after environmental stresses. We also show that tree vitality is crucial in shaping such responses. These findings are fundamental for the early assessment of ecosystem imbalances and decline under climate change.
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Affiliation(s)
- Valentina Vitali
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Philipp Schuler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | | | - Petra D'Odorico
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Claudia Guidi
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Stefan Klesse
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Katrin Meusburger
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Marcus Schaub
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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Mašek J, Tumajer J, Lange J, Vejpustková M, Kašpar J, Šamonil P, Chuman T, Kolář T, Rybníček M, Jeníček M, Vašíčková I, Čada V, Kaczka R, Rydval M, Svoboda M, Nedělčev O, Hais M, Treml V. Shifting climatic responses of tree rings and NDVI along environmental gradients. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168275. [PMID: 37923267 DOI: 10.1016/j.scitotenv.2023.168275] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 10/30/2023] [Accepted: 10/31/2023] [Indexed: 11/07/2023]
Abstract
Variations in the growth of aboveground biomass compartments such as tree stem and foliage significantly influence the carbon cycle of forest ecosystems. Yet the patterns of climate-driven responses of stem and foliage and their modulating factors remain poorly understood. In this study, we investigate the climatic response of Norway spruce (Picea abies) at 138 sites covering wide spatial and site fertility gradients in temperate forests in Central Europe. To characterize the annual growth rate of stem biomass and seasonal canopy vigor, we used tree-ring chronologies and time-series of NDVI derived from Landsat imagery. We calculated correlations of tree-ring width and NDVI with mean growing season temperature and standardized precipitation evapotranspiration index (SPEI). We evaluated how these climate responses varied with aridity index, soil category, stand age, and topographical factors. The results show that the climate-growth responses of tree rings shift from positive to negative for SPEI and from negative to positive for temperature from dry (warm) to wet (cold) areas. By contrast, NDVI revealed a negative response to temperature across the entire climatic gradient. The negative response of NDVI to temperature likely results from drought effects in warm areas and supporting effects of cloudy conditions on foliage greenness in wet areas. Contrary to NDVI, climate responses of tree rings differed according to stand age and were unaffected by local topographical features and soil conditions. Our findings demonstrate that the decoupling of stem and foliage climatic responses may result from their different climatic limitation along environmental gradients. These results imply that in temperate forest ecosystems, the canopy vigor may show different trends compared to stem growth under ongoing climate change.
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Affiliation(s)
- Jiří Mašek
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic.
| | - Jan Tumajer
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Jelena Lange
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Monika Vejpustková
- Forestry and Game Management Research Institute, Strnady 136, 252 02 Jíloviště, Czech Republic
| | - Jakub Kašpar
- Department of Forest Ecology, The Silva Tarouca Research Institute, Lidická 971/25, 602 Brno, Czech Republic
| | - Pavel Šamonil
- Department of Forest Ecology, The Silva Tarouca Research Institute, Lidická 971/25, 602 Brno, Czech Republic
| | - Tomáš Chuman
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Tomáš Kolář
- Department of Wood Science and Technology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Lesnická 3, 613 00 Brno, Czech Republic; Global Change Research Institute of the Czech Academy of Sciences, Bělidla 986/4a, 603 00 Brno, Czech Republic
| | - Michal Rybníček
- Department of Wood Science and Technology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Lesnická 3, 613 00 Brno, Czech Republic; Global Change Research Institute of the Czech Academy of Sciences, Bělidla 986/4a, 603 00 Brno, Czech Republic
| | - Michal Jeníček
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Ivana Vašíčková
- Department of Forest Ecology, The Silva Tarouca Research Institute, Lidická 971/25, 602 Brno, Czech Republic
| | - Vojtěch Čada
- Department of Forest Ecology, Faculty of Forestry and Wood Science, Czech University of Life Science, Kamýcká 129, 165 00 Prague, Czech Republic
| | - Ryszard Kaczka
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Miloš Rydval
- Department of Forest Ecology, Faculty of Forestry and Wood Science, Czech University of Life Science, Kamýcká 129, 165 00 Prague, Czech Republic
| | - Miroslav Svoboda
- Department of Forest Ecology, Faculty of Forestry and Wood Science, Czech University of Life Science, Kamýcká 129, 165 00 Prague, Czech Republic
| | - Ondřej Nedělčev
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Martin Hais
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
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Albrecht EC, Dobbert S, Pape R, Löffler J. Patterns, timing, and environmental drivers of growth in two coexisting green-stemmed Mediterranean alpine shrubs species. THE NEW PHYTOLOGIST 2024; 241:114-130. [PMID: 37753537 DOI: 10.1111/nph.19285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 09/05/2023] [Indexed: 09/28/2023]
Abstract
The Mediterranean alpine is one of the most vulnerable ecosystems under future environmental change. Yet, patterns, timing and environmental controls of plant growth are poorly investigated. We aimed at an improved understanding of growth processes, as well as stem swelling and shrinking patterns, by examining two common coexisting green-stemmed shrub species. Using dendrometers to measure daily stem diameter changes, we separated these changes into water-related shrinking and swelling and irreversible growth. Implementing correlation analysis, linear mixed effects models, and partial least squares regression on time series of stem diameter changes, with corresponding soil temperature and moisture data as environmental predictors, we found species-specific growth patterns related to different drought-adaptive strategies. We show that the winter-cold-adapted species Cytisus galianoi uses a drought tolerance strategy combined with a high ecological plasticity, and is, thus, able to gain competitive advantages under future climate warming. In contrast, Genista versicolor is restricted to a narrower ecological niche using a winter-cold escape and drought avoidance strategy, which might be of disadvantage in a changing climate. Pregrowth environmental conditions were more relevant than conditions during growth, controlling the species' resource availability. Thus, studies focusing on current driver constellations of growth may fail to predict a species' ecological niche and its potential future performance.
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Affiliation(s)
- Eike Corina Albrecht
- Department of Geography, University of Bonn, Meckenheimer Allee 166, D-53115, Bonn, Germany
| | - Svenja Dobbert
- Department of Geography, University of Bonn, Meckenheimer Allee 166, D-53115, Bonn, Germany
| | - Roland Pape
- Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, Gullbringvegen 36, Bø, N-3800, Norway
| | - Jörg Löffler
- Department of Geography, University of Bonn, Meckenheimer Allee 166, D-53115, Bonn, Germany
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Unterholzner L, Castagneri D, Cerrato R, Știrbu MI, Roibu CC, Carrer M. Climate response of a glacial relict conifer across its distribution range is invariant in space but not in time. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167512. [PMID: 37813259 DOI: 10.1016/j.scitotenv.2023.167512] [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: 07/25/2023] [Revised: 09/22/2023] [Accepted: 09/29/2023] [Indexed: 10/11/2023]
Abstract
Climate change impacts on forest trees will be particularly severe for relict species endemic to the subalpine forest, such as Pinus cembra in the Alps and Carpathians. Most current knowledge about the response of this species to climate comes from tree-ring width analysis. However, this approach cannot perform in-depth and highly time-resolved analysis on the climate influence on specific growth processes and xylem functions. We analyzed xylem anatomical traits from six sites covering most of the longitudinal range of this species. Associations between climate and cell number, lumen area and cell wall thickness were computed for the 1920-2010 period using climate records aligned to degree-day temperature sum thresholds. The anatomical chronologies were clearly distinct between the Alps and Carpathians. However, climate responses were similar for all sites, suggesting common species-specific response mechanisms. Temperature showed a positive correlation with both cell number and cell wall thickness. Cell lumen size exhibited an early positive association, followed by strong negative association with temperature and a positive one with precipitation. This highlights that the cell enlargement process was negatively related to high temperature at high elevation, where meristematic processes are rather supposed to be constrained by low temperatures. Therefore, long-term climate warming can have negative consequences on the xylem potential to transport water at all investigated sites. Moreover, in the last 30 years, we observed a slight anticipation of some responses and a decrease in climate sensitivity of some xylem parameters. Our findings provide evidence of temporally unstable but spatially consistent climate response of Pinus cembra from the Alps to the Carpathians. The low diversity in xylem phenotypic responses to climate suggests that future warming could extensively and evenly affect the species throughout its entire distribution.
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Affiliation(s)
- Lucrezia Unterholzner
- Department of Land, Environment, Agriculture and Forestry (TESAF), University of Padova, via dell'Università 16, 35020 Legnaro, Italy; Chair of Forest Growth and Woody Biomass Production, Technische Universität Dresden, Pienner Straße 8, 01737 Tharandt, Germany
| | - Daniele Castagneri
- Department of Land, Environment, Agriculture and Forestry (TESAF), University of Padova, via dell'Università 16, 35020 Legnaro, Italy.
| | - Riccardo Cerrato
- Department of Earth Sciences (DST), University of Pisa, via S. Maria 53, 56124 Pisa, Italy
| | - Marian-Ionuț Știrbu
- Forest Biometrics Laboratory, Faculty of Forestry, "Ștefan cel Mare" University of Suceava, Universității street, no. 13, 720229 Suceava, Romania
| | - Cătălin-Constantin Roibu
- Forest Biometrics Laboratory, Faculty of Forestry, "Ștefan cel Mare" University of Suceava, Universității street, no. 13, 720229 Suceava, Romania
| | - Marco Carrer
- Department of Land, Environment, Agriculture and Forestry (TESAF), University of Padova, via dell'Università 16, 35020 Legnaro, Italy
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Zhou B, Sterck F, Kruijt B, Fan ZX, Zuidema PA. Diel and seasonal stem growth responses to climatic variation are consistent across species in a subtropical tree community. THE NEW PHYTOLOGIST 2023; 240:2253-2264. [PMID: 37737019 DOI: 10.1111/nph.19275] [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: 07/14/2023] [Accepted: 09/04/2023] [Indexed: 09/23/2023]
Abstract
Understanding how intra-annual stem growth responds to atmospheric and soil conditions is essential for assessing the effects of climate extremes on forest productivity. In species-poor forests, such understanding can be obtained by studying stem growth of the dominant species. Yet, in species-rich (sub-)tropical forests, it is unclear whether these responses are consistent among species. We monitored intra-annual stem growth with high-resolution dendrometers for 27 trees belonging to 14 species over 5 yr in a montane subtropical forest. We quantified diel and seasonal stem growth patterns, verified to what extent observed growth patterns coincide across species and analysed their main climatic drivers. We found very consistent intra-annual growth patterns across species. Species varied in the rate but little in the timing of growth. Diel growth patterns revealed that - across species - trees mainly grew before dawn when vapour pressure deficit (VPD) was low. Within the year, trees mainly grew between May and August driven by temperature and VPD, but not by soil moisture. Our study reveals highly consistent stem growth patterns and climatic drivers at community level. Further studies are needed to verify whether these results hold across climates and forests, and whether they can be scaled up to estimate forest productivity.
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Affiliation(s)
- Bo Zhou
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
- Forest Ecology and Forest Management Group, Wageningen University and Research, Wageningen, 6700 AA, the Netherlands
| | - Frank Sterck
- Forest Ecology and Forest Management Group, Wageningen University and Research, Wageningen, 6700 AA, the Netherlands
| | - Bart Kruijt
- Water Systems and Global Change Group, Wageningen University and Research, Wageningen, 6700 AA, the Netherlands
| | - Ze-Xin Fan
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
- Ailaoshan Station for Subtropical Forest Ecosystem Studies, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Jingdong, Yunnan, 676209, China
| | - Pieter A Zuidema
- Forest Ecology and Forest Management Group, Wageningen University and Research, Wageningen, 6700 AA, the Netherlands
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10
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Potkay A, Feng X. Dynamically optimizing stomatal conductance for maximum turgor-driven growth over diel and seasonal cycles. AOB PLANTS 2023; 15:plad044. [PMID: 37899972 PMCID: PMC10601388 DOI: 10.1093/aobpla/plad044] [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: 12/22/2022] [Accepted: 07/04/2023] [Indexed: 10/31/2023]
Abstract
Stomata have recently been theorized to have evolved strategies that maximize turgor-driven growth over plants' lifetimes, finding support through steady-state solutions in which gas exchange, carbohydrate storage and growth have all reached equilibrium. However, plants do not operate near steady state as plant responses and environmental forcings vary diurnally and seasonally. It remains unclear how gas exchange, carbohydrate storage and growth should be dynamically coordinated for stomata to maximize growth. We simulated the gas exchange, carbohydrate storage and growth that dynamically maximize growth diurnally and annually. Additionally, we test whether the growth-optimization hypothesis explains nocturnal stomatal opening, particularly through diel changes in temperature, carbohydrate storage and demand. Year-long dynamic simulations captured realistic diurnal and seasonal patterns in gas exchange as well as realistic seasonal patterns in carbohydrate storage and growth, improving upon unrealistic carbohydrate responses in steady-state simulations. Diurnal patterns of carbohydrate storage and growth in day-long simulations were hindered by faulty modelling assumptions of cyclic carbohydrate storage over an individual day and synchronization of the expansive and hardening phases of growth, respectively. The growth-optimization hypothesis cannot currently explain nocturnal stomatal opening unless employing corrective 'fitness factors' or reframing the theory in a probabilistic manner, in which stomata adopt an inaccurate statistical 'memory' of night-time temperature. The growth-optimization hypothesis suggests that diurnal and seasonal patterns of stomatal conductance are driven by a dynamic carbon-use strategy that seeks to maintain homeostasis of carbohydrate reserves.
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Affiliation(s)
- Aaron Potkay
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Twin Cities, 500 Pillsbury Drive S.E., Minneapolis, MN 55455, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, 23rd Ave SE, Minneapolis, MN 55414, USA
| | - Xue Feng
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Twin Cities, 500 Pillsbury Drive S.E., Minneapolis, MN 55455, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, 23rd Ave SE, Minneapolis, MN 55414, USA
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11
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Dudney J, Latimer AM, van Mantgem P, Zald H, Willing CE, Nesmith JCB, Cribbs J, Milano E. The energy-water limitation threshold explains divergent drought responses in tree growth, needle length, and stable isotope ratios. GLOBAL CHANGE BIOLOGY 2023; 29:4368-4382. [PMID: 37089078 DOI: 10.1111/gcb.16740] [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: 09/08/2022] [Revised: 02/08/2023] [Accepted: 03/16/2023] [Indexed: 05/03/2023]
Abstract
Predicted increases in extreme droughts will likely cause major shifts in carbon sequestration and forest composition. Although growth declines during drought are widely documented, an increasing number of studies have reported both positive and negative responses to the same drought. These divergent growth patterns may reflect thresholds (i.e., nonlinear responses) promoted by changes in the dominant climatic constraints on tree growth. Here we tested whether stemwood growth exhibited linear or nonlinear responses to temperature and precipitation and whether stemwood growth thresholds co-occurred with multiple thresholds in source and sink processes that limit tree growth. We extracted 772 tree cores, 1398 needle length records, and 1075 stable isotope samples from 27 sites across whitebark pine's (Pinus albicaulis Engelm.) climatic niche in the Sierra Nevada. Our results indicated that a temperature threshold in stemwood growth occurred at 8.4°C (7.12-9.51°C; estimated using fall-spring maximum temperature). This threshold was significantly correlated with thresholds in foliar growth, as well as carbon (δ13 C) and nitrogen (δ15 N) stable isotope ratios, that emerged during drought. These co-occurring thresholds reflected the transition between energy- and water-limited tree growth (i.e., the E-W limitation threshold). This transition likely mediated carbon and nutrient cycling, as well as important differences in growth-defense trade-offs and drought adaptations. Furthermore, whitebark pine growing in energy-limited regions may continue to experience elevated growth in response to climate change. The positive effect of warming, however, may be offset by growth declines in water-limited regions, threatening the long-term sustainability of the recently listed whitebark pine species in the Sierra Nevada.
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Affiliation(s)
- Joan Dudney
- Environmental Studies Program, Santa Barbara, California, USA
- Bren School of Environmental Science & Management, UC Santa Barbara, Santa Barbara, California, USA
| | - Andrew M Latimer
- Department of Plant Sciences, University of California, Davis, California, USA
| | - Phillip van Mantgem
- U.S. Geological Survey, Western Ecological Research Center, Sacramento, California, USA
| | - Harold Zald
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, Oregon, USA
| | - Claire E Willing
- Department of Biology, Stanford University, Stanford, California, USA
- School of Environmental and Forest Sciences, University of Washington, Seattle, Washington, USA
| | | | - Jennifer Cribbs
- Department of Plant Sciences, University of California, Davis, California, USA
| | - Elizabeth Milano
- U.S. Geological Survey, Western Ecological Research Center, Sacramento, California, USA
- USDA Forest Service, Rocky Mountain Research Station, Moscow, Idaho, USA
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12
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Potkay A, Feng X. Do stomata optimize turgor-driven growth? A new framework for integrating stomata response with whole-plant hydraulics and carbon balance. THE NEW PHYTOLOGIST 2023; 238:506-528. [PMID: 36377138 DOI: 10.1111/nph.18620] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
Every existing optimal stomatal model uses photosynthetic carbon assimilation as a proxy for plant evolutionary fitness. However, assimilation and growth are often decoupled, making assimilation less ideal for representing fitness when optimizing stomatal conductance to water vapor and carbon dioxide. Instead, growth should be considered a closer proxy for fitness. We hypothesize stomata have evolved to maximize turgor-driven growth, instead of assimilation, over entire plants' lifetimes, improving their abilities to compete and reproduce. We develop a stomata model that dynamically maximizes whole-stem growth following principles from turgor-driven growth models. Stomata open to assimilate carbohydrates that supply growth and osmotically generate turgor, while stomata close to prevent losses of turgor and growth due to negative water potentials. In steady state, the growth optimization model captures realistic stomatal, growth, and carbohydrate responses to environmental cues, reconciles conflicting interpretations within existing stomatal optimization theories, and explains patterns of carbohydrate storage and xylem conductance observed during and after drought. Our growth optimization hypothesis introduces a new paradigm for stomatal optimization models, elevates the role of whole-plant carbon use and carbon storage in stomatal functioning, and has the potential to simultaneously predict gross productivity, net productivity, and plant mortality through a single, consistent modeling framework.
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Affiliation(s)
- Aaron Potkay
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
| | - Xue Feng
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
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13
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Körner C, Lenz A, Hoch G. Chronic in situ tissue cooling does not reduce lignification at the Swiss treeline but enhances the risk of 'blue' frost rings. ALPINE BOTANY 2023; 133:63-67. [PMID: 36945704 PMCID: PMC10023615 DOI: 10.1007/s00035-023-00293-6] [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: 01/19/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
In their 2013 paper, Lenz et al. illustrated how trees growing at the low-temperature limit respond to a chronic in situ warming or cooling by 3 K, by employing Peltier-thermostated branch collars that tracked ambient temperatures. The micro-coring-based analysis of seasonal tree ring formation included double-staining microtome cross sections for lignification, but these data had not been included in the publication. In this short communication, we complement these data, collected in 2009 at the Swiss treeline, and we show that a 3 K cooling that corresponds to a 500-600 m higher elevation, had no influence on lignification. However, when a frost event occurred during the early part of ring formation, the 3 K cooling produced a blue (non-lignified) layer of cells, followed by normally lignified cells for the rest of the season. Hence, the event did not affect the cambium, but interrupted cell wall maturation in cells that were in a critical developmental stage. We conclude, that chronic cooling does not affect lignification at treeline, but it increases the risk of frost damage in premature xylem tissue.
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Affiliation(s)
- Christian Körner
- Department of Environmental Sciences, Botany, University of Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland
| | - Armando Lenz
- Department of Environmental Sciences, Botany, University of Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland
| | - Günter Hoch
- Department of Environmental Sciences, Botany, University of Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland
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14
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Variability in Tree-ring Width and NDVI Responses to Climate at a Landscape Level. Ecosystems 2023. [DOI: 10.1007/s10021-023-00822-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
AbstractInter-annual climatically driven growth variability of above-ground biomass compartments (for example, tree stems and foliage) controls the intensity of carbon sequestration into forest ecosystems. However, understanding the differences between the climatic response of stem and foliage at the landscape level is limited. In this study, we examined the climate-growth response of stem and leaf biomass and their relationship for Pinus sylvestris (PISY) and Picea abies (PCAB) in topographically complex landscapes. We used tree-ring width chronologies and time series of the normalized difference vegetation index (NDVI) derived from high-resolution Landsat scenes as proxies for stem and leaf biomass, respectively. We then compared growth variability and climate-growth relationships of both biomass proxies between topographical categories. Our results show that the responses of tree rings to climate differ significantly from those found in NDVI, with the stronger climatic signal observed in tree rings. Topography had distinct but species-specific effects: At moisture-limited PISY stands, stem biomass (tree rings) was strongly topographically driven, and leaf biomass (NDVI) was relatively insensitive to topographic variability. In landscapes close to the climatic optimum of PCAB, the relationship between stem and leaf biomass was weak, and their correlations with climate were often inverse, with no significant effects of topography. Different climatic signals from NDVI and tree rings suggest that the response of canopy and stem growth to climate change might be decoupled. Furthermore, our results hint toward different prioritizations of biomass allocation in trees under stressful conditions which might change allometric relationships between individual tree compartments in the long term.
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15
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Tumajer J, Begović K, Čada V, Jenicek M, Lange J, Mašek J, Kaczka RJ, Rydval M, Svoboda M, Vlček L, Treml V. Ecological and methodological drivers of non-stationarity in tree growth response to climate. GLOBAL CHANGE BIOLOGY 2023; 29:462-476. [PMID: 36200330 DOI: 10.1111/gcb.16470] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
Radial tree growth is sensitive to environmental conditions, making observed growth increments an important indicator of climate change effects on forest growth. However, unprecedented climate variability could lead to non-stationarity, that is, a decoupling of tree growth responses from climate over time, potentially inducing biases in climate reconstructions and forest growth projections. Little is known about whether and to what extent environmental conditions, species, and model type and resolution affect the occurrence and magnitude of non-stationarity. To systematically assess potential drivers of non-stationarity, we compiled tree-ring width chronologies of two conifer species, Picea abies and Pinus sylvestris, distributed across cold, dry, and mixed climates. We analyzed 147 sites across the Europe including the distribution margins of these species as well as moderate sites. We calibrated four numerical models (linear vs. non-linear, daily vs. monthly resolution) to simulate growth chronologies based on temperature and soil moisture data. Climate-growth models were tested in independent verification periods to quantify their non-stationarity, which was assessed based on bootstrapped transfer function stability tests. The degree of non-stationarity varied between species, site climatic conditions, and models. Chronologies of P. sylvestris showed stronger non-stationarity compared with Picea abies stands with a high degree of stationarity. Sites with mixed climatic signals were most affected by non-stationarity compared with sites sampled at cold and dry species distribution margins. Moreover, linear models with daily resolution exhibited greater non-stationarity compared with monthly-resolved non-linear models. We conclude that non-stationarity in climate-growth responses is a multifactorial phenomenon driven by the interaction of site climatic conditions, tree species, and methodological features of the modeling approach. Given the existence of multiple drivers and the frequent occurrence of non-stationarity, we recommend that temporal non-stationarity rather than stationarity should be considered as the baseline model of climate-growth response for temperate forests.
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Affiliation(s)
- Jan Tumajer
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Krešimir Begović
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Vojtěch Čada
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Michal Jenicek
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jelena Lange
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jiří Mašek
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Ryszard J Kaczka
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Miloš Rydval
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Miroslav Svoboda
- Faculty of Forestry and Wood Science, Department of Forest Ecology, Czech University of Life Science, Prague, Czech Republic
| | - Lukáš Vlček
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
- Institute of Hydrodynamics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czech Republic
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16
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Wood structure explained by complex spatial source-sink interactions. Nat Commun 2022; 13:7824. [PMID: 36535928 PMCID: PMC9763502 DOI: 10.1038/s41467-022-35451-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 12/04/2022] [Indexed: 12/23/2022] Open
Abstract
Wood is a remarkable material with great cultural, economic, and biogeochemical importance. However, our understanding of its formation is poor. Key properties that have not been explained include the anatomy of growth rings (with consistent transitions from low-density earlywood to high density latewood), strong temperature-dependence of latewood density (used for historical temperature reconstructions), the regulation of cell size, and overall growth-temperature relationships in conifer and ring-porous tree species. We have developed a theoretical framework based on observations on Pinus sylvestris L. in northern Sweden. The observed anatomical properties emerge from our framework as a consequence of interactions in time and space between the production of new cells, the dynamics of developmental zone widths, and the distribution of carbohydrates across the developing wood. Here we find that the diffusion of carbohydrates is critical to determining final ring anatomy, potentially overturning current understanding of how wood formation responds to environmental variability and transforming our interpretation of tree rings as proxies of past climates.
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17
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Larysch E, Stangler DF, Puhlmann H, Rathgeber CBK, Seifert T, Kahle HP. The 2018 hot drought pushed conifer wood formation to the limit of its plasticity: Consequences for woody biomass production and tree ring structure. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1171-1185. [PMID: 35277910 DOI: 10.1111/plb.13399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
Hot droughts are expected to increase in Europe and disturb forest ecosystem functioning. Wood formation of trees has the potential to adapt to those events by compensatory mechanisms between the rates and durations of tracheid differentiation to form the typical pattern of vital wood anatomical structures. We monitored xylogenesis and measured wood anatomy of mature silver fir (Abies alba Mill.) and Scots pine (Pinus sylvestris L.) trees along an elevational gradient in the Black Forest during the hot drought year of 2018. We assessed the kinetics of tracheid differentiation and the final tracheid dimensions and quantified the relationship between rates and durations of cell differentiation over the growing season. Cell differentiation kinetics were decoupled, and temperature and water availability signals were imprinted in the tree ring structure. The sudden decline in woody biomass production provided evidence for a disruption in carbon sequestration processes due to heat and drought stress. Growth processes of Scots pine (pioneer species) were mainly affected by the spring drought, whereas silver fir (climax species) growth processes were more disturbed by the summer drought. Our study provides novel insights on the plasticity of wood formation and carbon allocation in temperate conifer tree species in response to extreme climatic events.
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Affiliation(s)
- E Larysch
- Chair of Forest Growth and Dendroecology, Albert-Ludwigs-University, Freiburg, Germany
| | - D F Stangler
- Chair of Forest Growth and Dendroecology, Albert-Ludwigs-University, Freiburg, Germany
| | - H Puhlmann
- Department of Soil and Environment, Forest Research Institute Baden-Württemberg, Freiburg, Germany
| | - C B K Rathgeber
- INRAE, SILVA, Université de Lorraine, AgroParisTech, Nancy, France
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - T Seifert
- Chair of Forest Growth and Dendroecology, Albert-Ludwigs-University, Freiburg, Germany
- Department of Forest and Wood Science, Stellenbosch University, Matieland, South Africa
| | - H-P Kahle
- Chair of Forest Growth and Dendroecology, Albert-Ludwigs-University, Freiburg, Germany
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18
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Martínez‐Sancho E, Treydte K, Lehmann MM, Rigling A, Fonti P. Drought impacts on tree carbon sequestration and water use - evidence from intra-annual tree-ring characteristics. THE NEW PHYTOLOGIST 2022; 236:58-70. [PMID: 35576102 PMCID: PMC9542003 DOI: 10.1111/nph.18224] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/04/2022] [Indexed: 05/22/2023]
Abstract
The impact of climate extremes on forest ecosystems is poorly understood but important for predicting carbon and water cycle feedbacks to climate. Some knowledge gaps still remain regarding how drought-related adjustments in intra-annual tree-ring characteristics directly impact tree carbon and water use. In this study we quantified the impact of an extreme summer drought on the water-use efficiency and carbon sequestration of four mature Norway spruce trees. We used detailed observations of wood formation (xylogenesis) and intra-annual tree-ring properties (quantitative wood anatomy and stable carbon isotopes) combined with physiological water-stress monitoring. During 41 d of tree water deficit, we observed an enrichment in 13 C but a reduction in cell enlargement and wall-thickening processes, which impacted the anatomical characteristics. These adjustments diminished carbon sequestration by 67% despite an 11% increase in water-use efficiency during drought. However, with the resumption of a positive hydric state in the stem, we observed a fast recovery of cell formation rates based on the accumulated assimilates produced during drought. Our findings enhance our understanding of carbon and water fluxes between the atmosphere and forest ecosystems, providing observational evidence on the tree intra-annual carbon sequestration and water-use efficiency dynamics to improve future generations of vegetation models.
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Affiliation(s)
- Elisabet Martínez‐Sancho
- Research Unit Forest DynamicsSwiss Federal Institute for Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland
| | - Kerstin Treydte
- Research Unit Forest DynamicsSwiss Federal Institute for Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland
| | - Marco M. Lehmann
- Research Unit Forest DynamicsSwiss Federal Institute for Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland
| | - Andreas Rigling
- Research Unit Forest DynamicsSwiss Federal Institute for Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsSwiss Federal Institute of Technology ETHUniversitaetsstrasse 168092ZurichSwitzerland
| | - Patrick Fonti
- Research Unit Forest DynamicsSwiss Federal Institute for Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland
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19
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Treml V, Tumajer J, Jandová K, Oulehle F, Rydval M, Čada V, Treydte K, Mašek J, Vondrovicová L, Lhotáková Z, Svoboda M. Increasing water-use efficiency mediates effects of atmospheric carbon, sulfur, and nitrogen on growth variability of central European conifers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156483. [PMID: 35675888 DOI: 10.1016/j.scitotenv.2022.156483] [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: 03/01/2022] [Revised: 05/31/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Climate controls forest biomass production through direct effects on cambial activity and indirectly through interactions with CO2, air pollution, and nutrient availability. The atmospheric concentration of CO2, sulfur and nitrogen deposition can also exert a significant indirect control on wood formation since these factors influence the stomatal regulation of transpiration and carbon uptake, that is, intrinsic water use efficiency (iWUE). Here we provide 120-year long tree-ring time series of iWUE, stem growth, climatic and combined sulfur and nitrogen (SN) deposition trends for two common tree species, Pinus sylvestris (PISY) and Picea abies (PCAB), at their lower and upper distribution margins in Central Europe. The main goals were to explain iWUE trends using theoretical scenarios including climatic and SN deposition data, and to assess the contribution of climate and iWUE to the observed growth trends. Our results showed that after a notable increase in iWUE between the 1950s and 1980s, this positive trend subsequently slowed down. The substantial rise of iWUE since the 1950s resulted from a combination of an accelerated increase in atmospheric CO2 concentrations (Ca) and a stable level of leaf intercellular CO2 (Ci). The offset of observed iWUE values above the trajectory of a constant Ci/Ca scenario was explained by trends in SN deposition (all sites) together with the variation of drought conditions (low-elevation sites only). Increasing iWUE over the 20th and 21st centuries improved tree growth at low-elevation drought-sensitive sites. In contrast, at high-elevation PCAB sites, growth was mainly stimulated by recent warming. We propose that SN pollution should be considered in order to explain the steep increase in iWUE of conifers in the 20th century throughout Central Europe and other regions with a significant SN deposition history.
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Affiliation(s)
- Václav Treml
- Faculty of Science, Charles University, Prague, Czechia.
| | - Jan Tumajer
- Faculty of Science, Charles University, Prague, Czechia
| | | | | | - Miloš Rydval
- Faculty of Forestry and Wood Science, Czech University of Life Science, Prague, Czechia
| | - Vojtěch Čada
- Faculty of Forestry and Wood Science, Czech University of Life Science, Prague, Czechia
| | - Kerstin Treydte
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Jiří Mašek
- Faculty of Science, Charles University, Prague, Czechia
| | | | | | - Miroslav Svoboda
- Faculty of Forestry and Wood Science, Czech University of Life Science, Prague, Czechia
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20
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Bar-On P, Yaakobi A, Moran U, Rozenstein O, Kopler I, Klein T. A montane species treeline is defined by both temperature and drought effects on growth season length. TREE PHYSIOLOGY 2022; 42:1700-1719. [PMID: 35738872 DOI: 10.1093/treephys/tpac070] [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: 03/28/2022] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
Montane treelines are defined by a threshold low temperature. However, what are the dynamics when the snow-free summer growth season coincides with a 6-month seasonal drought? We tested this fundamental question by measuring tree growth and leaf activity across elevations in Mt Hermon (2814 m; in Israel and Syria), where oak trees (Quercus look and Quercus boissieri) form an observed treeline at 1900 m. While in theory, individuals can be established at higher elevations (minimum daily temperature >6.5 °C for >4 months even at the summit), soil drying and vapor pressure deficit in summer enforces growth cessation in August, leaving only 2-3 months for tree growth. At lower elevations, Q. look Kotschy is replaced by Quercus cerris L. (1300 m) and Quercus calliprinos Webb (1000 m) in accompanying Q. boissieri Reut., and growth season length (GSL) is longer due to an earlier start in April. Leaf gas exchange continues during autumn, but assimilates are no longer utilized in growth. Interestingly, the growth and activity of Q. boissieri were equivalent to that of each of the other three species across the ~1 km elevation gradient. A planting experiment at 2100 m showed that seedlings of the four oak species survived the cold winter and showed budding of leaves in summer, but wilted in August. Our unique mountain site in the Eastern Mediterranean introduces a new factor to the formation of treelines, involving a drought limitation on GSL. This site presents the elevation edge for each species and the southern distribution edge for both the endemic Q. look and the broad-range Q. cerris. With ongoing warming, Q. look and Q. boissieri are slowly expanding to higher elevations, while Q. cerris is at risk of future extirpation.
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Affiliation(s)
- Peleg Bar-On
- Department of Plant and Environmental Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Assaf Yaakobi
- Department of Plant and Environmental Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Uri Moran
- Department of Plant and Environmental Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Offer Rozenstein
- Institute of Soil, Water, and Environmental Studies, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel
| | - Idan Kopler
- MIGAL - Galilee Research Institute, South Industrial Zone, PO Box 831, Kiryat Shmona 11016, Israel
| | - Tamir Klein
- Department of Plant and Environmental Science, Weizmann Institute of Science, Rehovot 7610001, Israel
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21
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Alpine shrub growth follows bimodal seasonal patterns across biomes - unexpected environmental controls. Commun Biol 2022; 5:793. [PMID: 35933562 PMCID: PMC9357034 DOI: 10.1038/s42003-022-03741-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/20/2022] [Indexed: 11/29/2022] Open
Abstract
Under climate change, cold-adapted alpine ecosystems are turning into hotspots of warming. However, the complexity of driving forces of growth, associated biomass gain and carbon storage of alpine shrubs is poorly understood. We monitored alpine growth mechanisms of six common shrub species across contrasting biomes, Mediterranean and tundra, using 257 dendrometers, recording stem diameter variability at high temporal resolution. Linking shrub growth to on-site environmental conditions, we modelled intra-annual growth patterns based on distributed lag non-linear models implemented with generalized additive models. We found pronounced bimodal growth patterns across biomes, and counterintuitively, within the cold-adapted biome, moisture, and within the drought-adapted biome, temperature was crucial, with unexpected consequences. In a warmer world, the Mediterranean alpine might experience strong vegetation shifts, biomass gain and greening, while the alpine tundra might see less changes in vegetation patterns, minor modifications of biomass stocks and rather browning. Generalized additive models reveal an unexpected environmental control in shrub growth across biomes.
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22
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Serra-Maluquer X, Gazol A, Anderegg WRL, Martínez-Vilalta J, Mencuccini M, Camarero JJ. Wood density and hydraulic traits influence species' growth response to drought across biomes. GLOBAL CHANGE BIOLOGY 2022; 28:3871-3882. [PMID: 35124877 DOI: 10.1111/gcb.16123] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/17/2021] [Accepted: 01/16/2022] [Indexed: 06/14/2023]
Abstract
Tree species display a wide variety of water-use strategies, growth rates and capacity to tolerate drought. However, if we want to forecast species capacity to cope with increasing aridity and drought, we need to identify which measurable traits confer resilience to drought across species. Here, we use a global tree ring network (65 species; 1931 site series of ring-width indices-RWI) to evaluate the relationship of long-term growth-drought sensitivity (RWI-SPEI drought index relationship) and short-term growth response to extreme drought episodes (resistance, recovery and resilience indices) with functional traits related to leaf, wood and hydraulic properties. Furthermore, we assess the influence of climate (temperature, precipitation and climatic water deficit) on these trait-growth relationships. We found a close correspondence between the long-term relationship between RWI and SPEI and resistance and recovery of tree growth to severe drought episodes. Species displaying a stronger RWI-SPEI relationship to drought and low resistance and high recovery to extreme drought episodes tended to have a higher wood density (WD) and more negative leaf minimum water potential (Ψmin). Such associations were largely maintained when accounting for direct climate effects. Our results indicate that, at a cross-species level and global scale, wood and hydraulic functional traits explain species' growth responses to drought at short- and long-term scales. These trait-growth response relationships can improve our understanding of the cross-species capacity to withstand climate change and inform models to better predict drought effects on forest ecosystem dynamics.
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Affiliation(s)
| | - Antonio Gazol
- Instituto Pirenaico de Ecología (IPE-CSIC), Zaragoza, Spain
| | | | - Jordi Martínez-Vilalta
- CREAF, Bellaterra (Cerdanyola del Vallés), Catalonia, Spain
- Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Maurizio Mencuccini
- CREAF, Bellaterra (Cerdanyola del Vallés), Catalonia, Spain
- ICREA, Barcelona, Spain
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23
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Cabon A, Kannenberg SA, Arain A, Babst F, Baldocchi D, Belmecheri S, Delpierre N, Guerrieri R, Maxwell JT, McKenzie S, Meinzer FC, Moore DJP, Pappas C, Rocha AV, Szejner P, Ueyama M, Ulrich D, Vincke C, Voelker SL, Wei J, Woodruff D, Anderegg WRL. Cross-biome synthesis of source versus sink limits to tree growth. Science 2022; 376:758-761. [PMID: 35549405 DOI: 10.1126/science.abm4875] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Uncertainties surrounding tree carbon allocation to growth are a major limitation to projections of forest carbon sequestration and response to climate change. The prevalence and extent to which carbon assimilation (source) or cambial activity (sink) mediate wood production are fundamentally important and remain elusive. We quantified source-sink relations across biomes by combining eddy-covariance gross primary production with extensive on-site and regional tree ring observations. We found widespread temporal decoupling between carbon assimilation and tree growth, underpinned by contrasting climatic sensitivities of these two processes. Substantial differences in assimilation-growth decoupling between angiosperms and gymnosperms were determined, as well as stronger decoupling with canopy closure, aridity, and decreasing temperatures. Our results reveal pervasive sink control over tree growth that is likely to be increasingly prominent under global climate change.
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Affiliation(s)
- Antoine Cabon
- School of Biological Sciences, University of Utah, Salt Lake City, UT, USA
| | | | - Altaf Arain
- McMaster Centre for Climate Change, McMaster University, Hamilton, Ontario L8S 4K1, Canada.,School of Earth, Environment and Society, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - Flurin Babst
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA.,Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, USA
| | - Dennis Baldocchi
- Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, USA
| | - Soumaya Belmecheri
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, USA
| | - Nicolas Delpierre
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, 91405 Orsay, France.,Institut Universitaire de France, 75231 Paris Cedex 05, France
| | | | - Justin T Maxwell
- Department of Geography, Indiana University, Bloomington, IN, USA
| | - Shawn McKenzie
- McMaster Centre for Climate Change, McMaster University, Hamilton, Ontario L8S 4K1, Canada.,School of Earth, Environment and Society, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | | | - David J P Moore
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA
| | - Christoforos Pappas
- Centre d'étude de la forêt, Université du Québec à Montréal, C.P. 8888, Succursale Centre-ville, Montréal, Quebec H3C 3P8, Canada.,Département Science et Technologie, Téluq, Université du Québec, Bureau 1105, Montréal, Quebec H2S 3L5, Canada
| | - Adrian V Rocha
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Paul Szejner
- Geology Institute, National Autonomous University of Mexico, Coyoacán, CDMX, Mexico
| | - Masahito Ueyama
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan
| | - Danielle Ulrich
- Department of Ecology, Montana State University, Bozeman, MT, USA
| | - Caroline Vincke
- Earth and Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Steven L Voelker
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, USA
| | - Jingshu Wei
- Department of Ecology, W. Szafer Institute of Botany, Polish Academy of Sciences, 31-512 Kraków, Poland
| | - David Woodruff
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR, USA
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24
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Eckes-Shephard AH, Ljungqvist FC, Drew DM, Rathgeber CBK, Friend AD. Wood Formation Modeling - A Research Review and Future Perspectives. FRONTIERS IN PLANT SCIENCE 2022; 13:837648. [PMID: 35401628 PMCID: PMC8984029 DOI: 10.3389/fpls.2022.837648] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/24/2022] [Indexed: 05/29/2023]
Abstract
Wood formation has received considerable attention across various research fields as a key process to model. Historical and contemporary models of wood formation from various disciplines have encapsulated hypotheses such as the influence of external (e.g., climatic) or internal (e.g., hormonal) factors on the successive stages of wood cell differentiation. This review covers 17 wood formation models from three different disciplines, the earliest from 1968 and the latest from 2020. The described processes, as well as their external and internal drivers and their level of complexity, are discussed. This work is the first systematic cataloging, characterization, and process-focused review of wood formation models. Remaining open questions concerning wood formation processes are identified, and relate to: (1) the extent of hormonal influence on the final tree ring structure; (2) the mechanism underlying the transition from earlywood to latewood in extratropical regions; and (3) the extent to which carbon plays a role as "active" driver or "passive" substrate for growth. We conclude by arguing that wood formation models remain to be fully exploited, with the potential to contribute to studies concerning individual tree carbon sequestration-storage dynamics and regional to global carbon sequestration dynamics in terrestrial vegetation models.
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Affiliation(s)
| | - Fredrik Charpentier Ljungqvist
- Department of History, Stockholm University, Stockholm, Sweden
- Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
- Swedish Collegium for Advanced Study, Uppsala, Sweden
| | - David M. Drew
- Department of Forest and Wood Science, Stellenbosch University, Stellenbosch, South Africa
| | - Cyrille B. K. Rathgeber
- Université de Lorraine, AgroParisTech, INRAE, SILVA, Nancy, France
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Andrew D. Friend
- Department of Geography, University of Cambridge, Cambridge, United Kingdom
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25
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Tumajer J, Scharnweber T, Smiljanic M, Wilmking M. Limitation by vapour pressure deficit shapes different intra-annual growth patterns of diffuse- and ring-porous temperate broadleaves. THE NEW PHYTOLOGIST 2022; 233:2429-2441. [PMID: 35000201 DOI: 10.1111/nph.17952] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Understanding the effects of temperature and moisture on radial growth is vital for assessing the impacts of climate change on carbon and water cycles. However, studies observing growth at sub-daily temporal scales remain scarce. We analysed sub-daily growth dynamics and its climatic drivers recorded by point dendrometers for 35 trees of three temperate broadleaved species during the years 2015-2020. We isolated irreversible growth driven by cambial activity from the dendrometer records. Next, we compared the intra-annual growth patterns among species and delimited their climatic optima. The growth of all species peaked at air temperatures between 12 and 16°C and vapour pressure deficit (VPD) below 0.1 kPa. Acer pseudoplatanus and Fagus sylvatica, both diffuse-porous, sustained growth under suboptimal VPD. Ring-porous Quercus robur experienced a steep decline of growth rates with reduced air humidity. This resulted in multiple irregular growth peaks of Q. robur during the year. By contrast, the growth patterns of the diffuse-porous species were always right-skewed unimodal with a peak in June between day of the year 150-170. Intra-annual growth patterns are shaped more by VPD than temperature. The different sensitivity of radial growth to VPD is responsible for unimodal growth patterns in both diffuse-porous species and multimodal growth pattern in Q. robur.
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Affiliation(s)
- Jan Tumajer
- Institute of Botany and Landscape Ecology, University of Greifswald, Soldmannstraβe 15, 17487, Greifswald, Germany
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Albertov 6, 12843, Prague, Czech Republic
| | - Tobias Scharnweber
- Institute of Botany and Landscape Ecology, University of Greifswald, Soldmannstraβe 15, 17487, Greifswald, Germany
| | - Marko Smiljanic
- Institute of Botany and Landscape Ecology, University of Greifswald, Soldmannstraβe 15, 17487, Greifswald, Germany
| | - Martin Wilmking
- Institute of Botany and Landscape Ecology, University of Greifswald, Soldmannstraβe 15, 17487, Greifswald, Germany
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26
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Cabon A, Anderegg WRL. Turgor-driven tree growth: scaling-up sink limitations from the cell to the forest. TREE PHYSIOLOGY 2022; 42:225-228. [PMID: 34788863 DOI: 10.1093/treephys/tpab146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Antoine Cabon
- School of Biological Sciences, University of Utah, Salt Lake City, UT84113, USA
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27
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Potkay A, Hölttä T, Trugman AT, Fan Y. Turgor-limited predictions of tree growth, height and metabolic scaling over tree lifespans. TREE PHYSIOLOGY 2022; 42:229-252. [PMID: 34296275 DOI: 10.1093/treephys/tpab094] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/18/2021] [Indexed: 06/13/2023]
Abstract
Increasing evidence suggests that tree growth is sink-limited by environmental and internal controls rather than by carbon availability. However, the mechanisms underlying sink-limitations are not fully understood and thus not represented in large-scale vegetation models. We develop a simple, analytically solved, mechanistic, turgor-driven growth model (TDGM) and a phloem transport model (PTM) to explore the mechanics of phloem transport and evaluate three hypotheses. First, phloem transport must be explicitly considered to accurately predict turgor distributions and thus growth. Second, turgor-limitations can explain growth-scaling with size (metabolic scaling). Third, turgor can explain realistic growth rates and increments. We show that mechanistic, sink-limited growth schemes based on plant turgor limitations are feasible for large-scale model implementations with minimal computational demands. Our PTM predicted nearly uniform sugar concentrations along the phloem transport path regardless of phloem conductance, stem water potential gradients and the strength of sink-demands contrary to our first hypothesis, suggesting that phloem transport is not limited generally by phloem transport capacity per se but rather by carbon demand for growth and respiration. These results enabled TDGM implementation without explicit coupling to the PTM, further simplifying computation. We test the TDGM by comparing predictions of whole-tree growth rate to well-established observations (site indices) and allometric theory. Our simple TDGM predicts realistic tree heights, growth rates and metabolic scaling over decadal to centurial timescales, suggesting that tree growth is generally sink and turgor limited. Like observed trees, our TDGM captures tree-size- and resource-based deviations from the classical ¾ power-law metabolic scaling for which turgor is responsible.
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Affiliation(s)
- Aaron Potkay
- Department of Earth and Planetary Sciences, Rutgers University, New Brunswick, NJ 08854, USA
| | - Teemu Hölttä
- Institute for Atmospheric and Earth System Research/Forest Sciences, University of Helsinki, Helsinki FI-00014, Finland
| | - Anna T Trugman
- Department of Geography, University of California at Santa Barbara, Santa Barbara, CA 93106, USA
| | - Ying Fan
- Department of Earth and Planetary Sciences, Rutgers University, New Brunswick, NJ 08854, USA
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28
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Dewar R, Hölttä T, Salmon Y. Exploring optimal stomatal control under alternative hypotheses for the regulation of plant sources and sinks. THE NEW PHYTOLOGIST 2022; 233:639-654. [PMID: 34637543 DOI: 10.1111/nph.17795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 09/19/2021] [Indexed: 06/13/2023]
Abstract
Experimental evidence that nonstomatal limitations to photosynthesis (NSLs) correlate with leaf sugar and/or leaf water status suggests the possibility that stomata adjust to maximise photosynthesis through a trade-off between leaf CO2 supply and NSLs, potentially involving source-sink interactions. However, the mechanisms regulating NSLs and sink strength, as well as their implications for stomatal control, remain uncertain. We used an analytically solvable model to explore optimal stomatal control under alternative hypotheses for source and sink regulation. We assumed that either leaf sugar concentration or leaf water potential regulates NSLs, and that either phloem turgor pressure or phloem sugar concentration regulates sink phloem unloading. All hypotheses led to realistic stomatal responses to light, CO2 and air humidity, including conservative behaviour for the intercellular-to-atmospheric CO2 concentration ratio. Sugar-regulated and water-regulated NSLs are distinguished by the presence/absence of a stomatal closure response to changing sink strength. Turgor-regulated and sugar-regulated phloem unloading are distinguished by the presence/absence of stomatal closure under drought and avoidance/occurrence of negative phloem turgor. Results from girdling and drought experiments on Pinus sylvestris, Betula pendula, Populus tremula and Picea abies saplings are consistent with optimal stomatal control under sugar-regulated NSLs and turgor-regulated unloading. Our analytical results provide a simple representation of stomatal responses to above-ground and below-ground environmental factors and sink activity.
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Affiliation(s)
- Roderick Dewar
- Faculty of Science, Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, PO Box 68, Gustaf Hällströmin katu 2b, Helsinki, 00014, Finland
- Plant Sciences Division, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Teemu Hölttä
- Faculty of Agriculture and Forestry, Institute for Atmospheric and Earth System Research/Forest Sciences, University of Helsinki, PO Box 27, Latokartanonkaari 7, Helsinki, 00014, Finland
| | - Yann Salmon
- Faculty of Science, Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, PO Box 68, Gustaf Hällströmin katu 2b, Helsinki, 00014, Finland
- Faculty of Agriculture and Forestry, Institute for Atmospheric and Earth System Research/Forest Sciences, University of Helsinki, PO Box 27, Latokartanonkaari 7, Helsinki, 00014, Finland
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29
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Etzold S, Sterck F, Bose AK, Braun S, Buchmann N, Eugster W, Gessler A, Kahmen A, Peters RL, Vitasse Y, Walthert L, Ziemińska K, Zweifel R. Number of growth days and not length of the growth period determines radial stem growth of temperate trees. Ecol Lett 2021; 25:427-439. [PMID: 34882952 PMCID: PMC9299935 DOI: 10.1111/ele.13933] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/07/2021] [Accepted: 11/07/2021] [Indexed: 01/02/2023]
Abstract
Radial stem growth dynamics at seasonal resolution are essential to understand how forests respond to climate change. We studied daily radial growth of 160 individuals of seven temperate tree species at 47 sites across Switzerland over 8 years. Growth of all species peaked in the early part of the growth season and commenced shortly before the summer solstice, but with species-specific seasonal patterns. Day length set a window of opportunity for radial growth. Within this window, the probability of daily growth was constrained particularly by air and soil moisture, resulting in intermittent growth to occur only on 29 to 77 days (30% to 80%) within the growth period. The number of days with growth largely determined annual growth, whereas the growth period length contributed less. We call for accounting for these non-linear intra-annual and species-specific growth dynamics in tree and forest models to reduce uncertainties in predictions under climate change.
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Affiliation(s)
- Sophia Etzold
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Frank Sterck
- Forest Ecology and Management Group, Wageningen University, Wageningen, The Netherlands
| | - Arun K Bose
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland.,Forestry and Wood Technology Discipline, Khulna University, Khulna, Bangladesh
| | - Sabine Braun
- Institute of Applied Plant Biology AG, Witterswil, Switzerland
| | - Nina Buchmann
- Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
| | - Werner Eugster
- Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland.,Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland
| | - Ansgar Kahmen
- Department of Environmental Science, Physiological Plant Ecology, University of Basel, Basel, Switzerland
| | - Richard L Peters
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland.,Laboratory of Plant Ecology, Ghent University, Ghent, Belgium.,Forest is Life, TERRA Teaching and Research Centre, Gembloux Agro Bio-Tech, University of Liège, Liège, Belgium
| | - Yann Vitasse
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Lorenz Walthert
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Kasia Ziemińska
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland.,Department of Plant Ecology and Evolution, Uppsala University, Uppsala, Sweden
| | - Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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30
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Liu X, Ziaco E, Biondi F. Water-Use Efficiency of Co-occurring Sky-Island Pine Species in the North American Great Basin. FRONTIERS IN PLANT SCIENCE 2021; 12:787297. [PMID: 34925427 PMCID: PMC8678526 DOI: 10.3389/fpls.2021.787297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/02/2021] [Indexed: 06/14/2023]
Abstract
Water-use efficiency (WUE), weighing the balance between plant transpiration and growth, is a key characteristic of ecosystem functioning and a component of tree drought resistance. Seasonal dynamics of tree-level WUE and its connections with drought variability have not been previously explored in sky-island montane forests. We investigated whole-tree transpiration and stem growth of bristlecone (Pinus longaeva) and limber pine (Pinus flexilis) within a high-elevation stand in central-eastern Nevada, United States, using sub-hourly measurements over 5 years (2013-2017). A moderate drought was generally observed early in the growing season, whereas interannual variability of summer rains determined drought levels between years, i.e., reducing drought stress in 2013-2014 while enhancing it in 2015-2017. Transpiration and basal area increment (BAI) of both pines were coupled throughout June-July, resulting in a high but relatively constant early season WUE. In contrast, both pines showed high interannual plasticity in late-season WUE, with a predominant role of stem growth in driving WUE. Overall, bristlecone pine was characterized by a lower WUE compared to limber pine. Dry or wet episodes in the late growing season overrode species differences. Our results suggested thresholds of vapor pressure deficit and soil moisture that would lead to opposite responses of WUE to late-season dry or wet conditions. These findings provide novel insights and clarify potential mechanisms modulating tree-level WUE in sky-island ecosystems of semi-arid regions, thereby helping land managers to design appropriate science-based strategies and reduce uncertainties associated with the impact of future climatic changes.
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Affiliation(s)
- Xinsheng Liu
- School of Geography and Tourism, Anhui Normal University, Wuhu, China
- DendroLab, Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV, United States
- College of Tourism and Geography, Jiujiang University, Jiujiang, China
| | - Emanuele Ziaco
- Department of Ecology and Genetics, Plant Ecology and Evolution, University of Uppsala, Uppsala, Sweden
| | - Franco Biondi
- DendroLab, Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV, United States
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31
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Konings AG, Saatchi SS, Frankenberg C, Keller M, Leshyk V, Anderegg WRL, Humphrey V, Matheny AM, Trugman A, Sack L, Agee E, Barnes ML, Binks O, Cawse‐Nicholson K, Christoffersen BO, Entekhabi D, Gentine P, Holtzman NM, Katul GG, Liu Y, Longo M, Martinez‐Vilalta J, McDowell N, Meir P, Mencuccini M, Mrad A, Novick KA, Oliveira RS, Siqueira P, Steele‐Dunne SC, Thompson DR, Wang Y, Wehr R, Wood JD, Xu X, Zuidema PA. Detecting forest response to droughts with global observations of vegetation water content. GLOBAL CHANGE BIOLOGY 2021; 27:6005-6024. [PMID: 34478589 PMCID: PMC9293345 DOI: 10.1111/gcb.15872] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 08/23/2021] [Indexed: 05/11/2023]
Abstract
Droughts in a warming climate have become more common and more extreme, making understanding forest responses to water stress increasingly pressing. Analysis of water stress in trees has long focused on water potential in xylem and leaves, which influences stomatal closure and water flow through the soil-plant-atmosphere continuum. At the same time, changes of vegetation water content (VWC) are linked to a range of tree responses, including fluxes of water and carbon, mortality, flammability, and more. Unlike water potential, which requires demanding in situ measurements, VWC can be retrieved from remote sensing measurements, particularly at microwave frequencies using radar and radiometry. Here, we highlight key frontiers through which VWC has the potential to significantly increase our understanding of forest responses to water stress. To validate remote sensing observations of VWC at landscape scale and to better relate them to data assimilation model parameters, we introduce an ecosystem-scale analog of the pressure-volume curve, the non-linear relationship between average leaf or branch water potential and water content commonly used in plant hydraulics. The sources of variability in these ecosystem-scale pressure-volume curves and their relationship to forest response to water stress are discussed. We further show to what extent diel, seasonal, and decadal dynamics of VWC reflect variations in different processes relating the tree response to water stress. VWC can also be used for inferring belowground conditions-which are difficult to impossible to observe directly. Lastly, we discuss how a dedicated geostationary spaceborne observational system for VWC, when combined with existing datasets, can capture diel and seasonal water dynamics to advance the science and applications of global forest vulnerability to future droughts.
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Affiliation(s)
| | - Sassan S. Saatchi
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - Michael Keller
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
- United States Forest ServiceWashingtonDCUSA
| | | | | | | | | | - Anna Trugman
- University of California ‐ Santa BarbaraSanta BarbaraCAUSA
| | - Lawren Sack
- University of California ‐ Los AngelesLos AngelesCAUSA
| | | | | | - Oliver Binks
- The Australian National UniversityCanberraACTAustralia
| | | | | | | | | | | | | | | | - Marcos Longo
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jordi Martinez‐Vilalta
- Centre de Recerca Ecològica i Aplicacions Forestals (CREAF)BarcelonaSpain
- Universitat Autònoma de BarcelonaBarcelonaSpain
| | - Nate McDowell
- Pacific Northwest National LaboratoryRichlandWAUSA
- Washington State UniversityPullmanWAUSA
| | - Patrick Meir
- The Australian National UniversityCanberraACTAustralia
- University of EdinburghEdinburghUK
| | - Maurizio Mencuccini
- Centre de Recerca Ecològica i Aplicacions Forestals (CREAF)BarcelonaSpain
- Institució Catalana de Recerca i Estudis Avançats (ICREA)BarcelonaSpain
| | - Assaad Mrad
- University of California ‐ IrvineIrvineCAUSA
| | | | | | | | | | - David R. Thompson
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Yujie Wang
- California Institute of TechnologyPasadenaCAUSA
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32
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Balanzategui D, Nordhauß H, Heinrich I, Biondi F, Miley N, Hurley AG, Ziaco E. Wood Anatomy of Douglas-Fir in Eastern Arizona and Its Relationship With Pacific Basin Climate. FRONTIERS IN PLANT SCIENCE 2021; 12:702442. [PMID: 34539695 PMCID: PMC8440974 DOI: 10.3389/fpls.2021.702442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
Dendroclimatic reconstructions, which are a well-known tool for extending records of climatic variability, have recently been expanded by using wood anatomical parameters. However, the relationships between wood cellular structures and large-scale climatic patterns, such as El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), are still not completely understood, hindering the potential for wood anatomy as a paleoclimatic proxy. To better understand the teleconnection between regional and local climate processes in the western United States, our main objective was to assess the value of these emerging tree-ring parameters for reconstructing climate dynamics. Using Confocal Laser Scanning Microscopy, we measured cell lumen diameter and cell wall thickness (CWT) for the period 1966 to 2015 in five Douglas-firs [Pseudotsuga menziesii (Mirb.) Franco] from two sites in eastern Arizona (United States). Dendroclimatic analysis was performed using chronologies developed for 10 equally distributed sectors of the ring and daily climatic records to identify the strongest climatic signal for each sector. We found that lumen diameter in the first ring sector was sensitive to previous fall-winter temperature (September 25th to January 23rd), while a precipitation signal (October 27th to February 13th) persisted for the entire first half of the ring. The lack of synchronous patterns between trees for CWT prevented conducting meaningful climate-response analysis for that anatomical parameter. Time series of lumen diameter showed an anti-phase relationship with the Southern Oscillation Index (a proxy for ENSO) at 10 to 14year periodicity and particularly in 1980-2005, suggesting that chronologies of wood anatomical parameters respond to multidecadal variability of regional climatic modes. Our findings demonstrate the potential of cell structural characteristics of southwestern United States conifers for reconstructing past climatic variability, while also improving our understanding of how large-scale ocean-atmosphere interactions impact local hydroclimatic patterns.
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Affiliation(s)
- Daniel Balanzategui
- GFZ German Research Centre for Geosciences, Potsdam, Germany
- Institute of Geography, Humboldt-University, Berlin, Germany
- Department of Natural Sciences, DAI German Archaeological Institute, Berlin, Germany
| | - Henry Nordhauß
- GFZ German Research Centre for Geosciences, Potsdam, Germany
| | - Ingo Heinrich
- GFZ German Research Centre for Geosciences, Potsdam, Germany
- Institute of Geography, Humboldt-University, Berlin, Germany
- Department of Natural Sciences, DAI German Archaeological Institute, Berlin, Germany
| | - Franco Biondi
- DendroLab, Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV, United States
| | - Nicholas Miley
- DendroLab, Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV, United States
| | - Alexander G. Hurley
- DendroLab, Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV, United States
| | - Emanuele Ziaco
- GFZ German Research Centre for Geosciences, Potsdam, Germany
- Department of Ecology and Genetics, Plant Ecology and Evolution, University of Uppsala, Uppsala, Sweden
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33
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Jupa R, Krabičková D, Plichta R, Mayr S, Gloser V. Do angiosperm tree species adjust intervessel lateral contact in response to soil drought? PHYSIOLOGIA PLANTARUM 2021; 172:2048-2058. [PMID: 33876443 DOI: 10.1111/ppl.13435] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 04/15/2021] [Indexed: 06/12/2023]
Abstract
During soil drought (i.e. limited soil water availability to plants), woody species may adjust the structure of their vessel network to improve their resistance against future soil drought stress. Impacts of soil drought on intervessel lateral contact remain poorly understood despite of its significance to xylem transport efficiency and safety. Here, we analysed drought-induced modifications in xylem structures of temperate angiosperm trees with a focus on intervessel lateral contact. Anatomical analyses were performed both in stems of seedlings cultivated under different substrate water availability and annual rings of mature individuals developed during years of low and high soil drought intensities. In response to limited water availability, a decrease in vessel diameter (up to -20%) and simultaneous increase in vessel density (up to +60%) were observed both in seedlings and mature trees. Conversely, there were only small and inconsistent drought-induced changes in intervessel contact frequency and intervessel contact fraction (typically up to ±15%) observed across species, indicating that intervessel lateral contact is a conservative trait. The small adjustments in intervessel lateral contacts were primarily driven by changes in the contact frequencies between neighbouring vessels (i.e. vessel grouping) rather than by changes in proportions of shared cell walls. Our results demonstrate that angiosperm tree species, despite remarkable adjustments in vessel dimensions and densities upon soil drought, exhibit surprisingly invariant intervessel lateral contact architecture.
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Affiliation(s)
- Radek Jupa
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
- Department of Forest Botany, Dendrology and Geobiocenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic
| | - Dita Krabičková
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Roman Plichta
- Department of Forest Botany, Dendrology and Geobiocenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic
| | - Stefan Mayr
- Department of Botany, University of Innsbruck, Innsbruck, Austria
| | - Vít Gloser
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
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34
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Rademacher T, Fonti P, LeMoine JM, Fonti MV, Basler D, Chen Y, Friend AD, Seyednasrollah B, Eckes-Shephard AH, Richardson AD. Manipulating phloem transport affects wood formation but not local nonstructural carbon reserves in an evergreen conifer. PLANT, CELL & ENVIRONMENT 2021; 44:2506-2521. [PMID: 34043242 DOI: 10.1111/pce.14117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 06/12/2023]
Abstract
How variations in carbon supply affect wood formation remains poorly understood in particular in mature forest trees. To elucidate how carbon supply affects carbon allocation and wood formation, we attempted to manipulate carbon supply to the cambial region by phloem girdling and compression during the mid- and late-growing season and measured effects on structural development, CO2 efflux and nonstructural carbon reserves in stems of mature white pines. Wood formation and stem CO2 efflux varied with a location relative to treatment (i.e., above or below the restriction). We observed up to twice as many tracheids formed above versus below the treatment after the phloem transport manipulation, whereas the cell-wall area decreased only slightly below the treatments, and cell size did not change relative to the control. Nonstructural carbon reserves in the xylem, needles and roots were largely unaffected by the treatments. Our results suggest that low and high carbon supply affects wood formation, primarily through a strong effect on cell proliferation, and respiration, but local nonstructural carbon concentrations appear to be maintained homeostatically. This contrasts with reports of decoupling of source activity and wood formation at the whole-tree or ecosystem level, highlighting the need to better understand organ-specific responses, within-tree feedbacks, as well as phenological and ontogenetic effects on sink-source dynamics.
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Affiliation(s)
- Tim Rademacher
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Patrick Fonti
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - James M LeMoine
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Marina V Fonti
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Institute of Ecology and Geography, Siberian Federal University, Krasnoyarsk, Russian Federation
| | - David Basler
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Yizhao Chen
- Department of Geography, University of Cambridge, Cambridge, UK
| | - Andrew D Friend
- Department of Geography, University of Cambridge, Cambridge, UK
| | - Bijan Seyednasrollah
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | | | - Andrew D Richardson
- School of Informatics, Computing, and Cyber Security, Northern Arizona University, Flagstaff, Arizona, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
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35
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Körner C. The cold range limit of trees. Trends Ecol Evol 2021; 36:979-989. [PMID: 34272073 DOI: 10.1016/j.tree.2021.06.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/13/2021] [Accepted: 06/21/2021] [Indexed: 11/27/2022]
Abstract
At high elevation or latitude, trees reach low-temperature range limits. In attempting an explanation, the range limits of individual tree species (set by freezing tolerance) and the general limit of the life-form tree (set by thermal growth constraints) need to be distinguished. The general cold edge of the fundamental niche of trees is termed the treeline, by definition, the lower edge of the alpine belt, a most important bioclimatological reference line. Trees can be absent from the treeline due to disturbances or biotic interactions. The actual local edge of tree distribution, the delineation of the realized niche, is driven by stochastic effects. Therefore, treeline theory and hypothesis testing is inevitably tied to the fundamental niche concept.
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Affiliation(s)
- Christian Körner
- Department of Environmental Sciences, Botany, University of Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland.
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36
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Dox I, Prislan P, Gričar J, Mariën B, Delpierre N, Flores O, Leys S, Rathgeber CBK, Fonti P, Campioli M. Drought elicits contrasting responses on the autumn dynamics of wood formation in late successional deciduous tree species. TREE PHYSIOLOGY 2021; 41:1171-1185. [PMID: 33616191 DOI: 10.1093/treephys/tpaa175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 12/17/2020] [Accepted: 12/21/2020] [Indexed: 05/12/2023]
Abstract
Research on wood phenology has mainly focused on reactivation of the cambium in spring. In this study we investigated if summer drought advances cessation of wood formation and if it has any influence on wood structure in late successional forest trees of the temperate zone. The end of xylogenesis was monitored between August and November in stands of European beech and pedunculate oak in Belgium for two consecutive years, 2017 and 2018, with the latter year having experienced an exceptional summer drought. Wood formation in oak was affected by the drought, with oak trees ceasing cambial activity and wood maturation about 3 weeks earlier in 2018 compared with 2017. Beech ceased wood formation before oak, but its wood phenology did not differ between years. Furthermore, between the 2 years, no significant difference was found in ring width, percentage of mature fibers in the late season, vessel size and density. In 2018, beech did show thinner fiber walls, whereas oak showed thicker walls. In this paper, we showed that summer drought can have an important impact on late season wood phenology xylem development. This will help to better understand forest ecosystems and improve forest models.
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Affiliation(s)
- Inge Dox
- Research Group of Plants and Ecosystems, PLECO, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Peter Prislan
- Department of Forest Yield and Silviculture & Department for Forest Technique and Economics, Slovenian Forestry Institute, Večna pot 2, 1000 Ljubljana, Slovenia
| | - Jožica Gričar
- Department of Forest Yield and Silviculture & Department for Forest Technique and Economics, Slovenian Forestry Institute, Večna pot 2, 1000 Ljubljana, Slovenia
| | - Bertold Mariën
- Research Group of Plants and Ecosystems, PLECO, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Nicolas Delpierre
- Ecologie Systématique et Evolution, Université Paris-Saclay, CNRS, AgroParisTech, rue du Doyen André Guinier 362, 91405, Orsay Cedex, France
- Institut Universitaire de France (IUF), rue Descartes 1, 75231 Paris, France
| | - Omar Flores
- Research Group of Plants and Ecosystems, PLECO, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Sebastien Leys
- Research Group of Plants and Ecosystems, PLECO, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Cyrille B K Rathgeber
- SILVA, Université de Lorraine, AgroParisTech, INRAE, Cours Léopold 34, 54000 Nancy, France
| | - Patrick Fonti
- Dendrosciences group, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Matteo Campioli
- Research Group of Plants and Ecosystems, PLECO, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
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37
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Processing and Extraction of Seasonal Tree Physiological Parameters from Stem Radius Time Series. FORESTS 2021. [DOI: 10.3390/f12060765] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Radial stem size changes, measured with automated dendrometers at intra-daily resolution, offer great potential to link environmental conditions with tree physiology at the seasonal scale. Such measurements need to be time-aligned, cleaned of outliers and shifts, gap-filled and analysed for reversible (water-related) and irreversible (growth-related) fractions to obtain physiologically meaningful data. Therefore, comprehensive tools are needed for reproducible data processing and analytics of dendrometer data. Here we present a transparent method, compiled in the R package treenetproc, to turn raw dendrometer data into clean, physiologically interpretable information, i.e., stem growth, tree water deficit, growth phenological phases, mean daily shrinkage and their respective timings. The removal of errors is facilitated by additional functions and supported with graphical visualizations. To ensure reproducible data handling, the processing parameters and induced changes to the raw data are documented in the output and, thus, are a step towards a standardized processing of automatically measured stem radius time series. We discuss examples, such as the seasonality of growth or the dependence of growth on atmospheric and soil drought. The presented growth and water-related physiological variables at high temporal resolution offer novel physiological insights into the seasonally varying responses of trees to changing environmental conditions.
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38
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Mullin M, Klutsch JG, Cale JA, Hussain A, Zhao S, Whitehouse C, Erbilgin N. Primary and Secondary Metabolite Profiles of Lodgepole Pine Trees Change with Elevation, but Not with Latitude. J Chem Ecol 2021; 47:280-293. [PMID: 33651224 DOI: 10.1007/s10886-021-01249-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/17/2020] [Accepted: 01/15/2021] [Indexed: 12/01/2022]
Abstract
Climate change has a large influence on plant functional and phenotypic traits including plant primary and secondary metabolites. One well-established approach to investigating the variation in plant metabolites involves studying plant populations along elevation and latitude gradients. We considered how two space-for-time climate change gradients (elevation and latitude) influence carbohydrate reserves (soluble sugars, starches) and secondary metabolites (monoterpenes, diterpene resin acids) of lodgepole pine trees in western Canada. We were particularly interested in the relationship of terpenes and carbohydrates with a wide range of tree, site, and climatic factors. We found that only elevation had a strong influence on the expression of both terpenes and carbohydrates of trees. Specifically, as elevation increased, concentrations of monoterpenes and diterpenes generally increased and soluble sugars (glucose, sucrose, total sugars) decreased. In contrast, latitude had no impact on either of terpenes or carbohydrates. Furthermore, we found a positive relationship between concentrations of starch and total terpenes and diterpenes in the elevation study; whereas neither starches nor sugars were correlated to terpenes in the latitude study. Similarly, both terpenes and carbohydrates had a much greater number of significant correlations to site characteristics such as slope, basal area index, and sand basal area, in the elevational than in the latitude study. Overall, these results support the conclusion that both biotic and abiotic factors likely drive the patterns of primary and secondary metabolite profiles of lodgepole pine along geographical gradients. Also, presence of a positive relationship between terpenes and starches suggests an interaction between primary ad secondary metabolites of lodgepole pine trees.
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Affiliation(s)
- Melanie Mullin
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada
| | - J G Klutsch
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada
| | - J A Cale
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada
| | - A Hussain
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada
| | - S Zhao
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada
| | - C Whitehouse
- Alberta Agriculture and Forestry, 9920 108 Street, Edmonton, Alberta, T5K 2M4, Canada
| | - Nadir Erbilgin
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada.
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39
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Babst F, Friend AD, Karamihalaki M, Wei J, von Arx G, Papale D, Peters RL. Modeling Ambitions Outpace Observations of Forest Carbon Allocation. TRENDS IN PLANT SCIENCE 2021; 26:210-219. [PMID: 33168468 DOI: 10.1016/j.tplants.2020.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 08/17/2020] [Accepted: 10/08/2020] [Indexed: 06/11/2023]
Abstract
There have been vociferous calls for 'tree-centered' vegetation models to refine predictions of forest carbon (C) cycling. Unfortunately, our global survey at flux-tower sites indicates insufficient empirical data support for this much-needed model development. We urge for a new generation of studies across large environmental gradients that strategically pair long-term ecosystem monitoring with manipulative experiments on mature trees. For this, we outline a versatile experimental framework to build cross-scale data archives of C uptake and allocation to structural, non-structural, and respiratory sinks. Community-wide efforts and discussions are needed to implement this framework, especially in hitherto underrepresented tropical forests. Global coordination and realistic priorities for data collection will thereby be key to achieve and maintain adequate empirical support for tree-centered vegetation modeling.
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Affiliation(s)
- Flurin Babst
- W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Krakow, Poland; Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland.
| | - Andrew D Friend
- Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
| | - Maria Karamihalaki
- W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Krakow, Poland; Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Jingshu Wei
- W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Krakow, Poland; Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Georg von Arx
- Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Dario Papale
- DIBAF, University of Tuscia, Largo dell'Universita, 01100 Viterbo, Italy
| | - Richard L Peters
- Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland; Laboratory of Plant Ecology, Ghent University, Coupure Links 653, 9000 Gent, Belgium
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40
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Hartmann FP, Rathgeber CBK, Badel É, Fournier M, Moulia B. Modelling the spatial crosstalk between two biochemical signals explains wood formation dynamics and tree-ring structure. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:1727-1737. [PMID: 33247732 DOI: 10.1093/jxb/eraa558] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
In conifers, xylogenesis during a growing season produces a very characteristic tree-ring structure: large, thin-walled earlywood cells followed by narrow, thick-walled latewood cells. Although many factors influence the dynamics of differentiation and the final dimensions of xylem cells, the associated patterns of variation remain very stable from one year to the next. While radial growth is characterized by an S-shaped curve, the widths of xylem differentiation zones exhibit characteristic skewed bell-shaped curves. These elements suggest a strong internal control of xylogenesis. It has long been hypothesized that much of this regulation relies on a morphogenetic gradient of auxin. However, recent modelling studies have shown that while this hypothesis could account for the dynamics of stem radial growth and the zonation of the developing xylem, it failed to reproduce the characteristic tree-ring structure. Here, we investigated the hypothesis of regulation by a crosstalk between auxin and a second biochemical signal, by using computational morphodynamics. We found that, in conifers, such a crosstalk is sufficient to simulate the characteristic features of wood formation dynamics, as well as the resulting tree-ring structure. In this model, auxin controls cell enlargement rates while another signal (e.g. cytokinin, tracheary element differentiation inhibitory factor) drives cell division and auxin polar transport.
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Affiliation(s)
- Félix P Hartmann
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, France
| | | | - Éric Badel
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, France
| | - Meriem Fournier
- Université de Lorraine, AgroParisTech, INRAE, Silva, Nancy, France
| | - Bruno Moulia
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, France
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41
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Peters RL, Steppe K, Cuny HE, De Pauw DJW, Frank DC, Schaub M, Rathgeber CBK, Cabon A, Fonti P. Turgor - a limiting factor for radial growth in mature conifers along an elevational gradient. THE NEW PHYTOLOGIST 2021; 229:213-229. [PMID: 32790914 DOI: 10.1111/nph.16872] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 07/29/2020] [Indexed: 05/17/2023]
Abstract
A valid representation of intra-annual wood formation processes in global vegetation models is vital for assessing climate change impacts on the forest carbon stock. Yet, wood formation is generally modelled with photosynthesis, despite mounting evidence that cambial activity is rather directly constrained by limiting environmental factors. Here, we apply a state-of-the-art turgor-driven growth model to simulate 4 yr of hourly stem radial increment from Picea abies (L.) Karst. and Larix decidua Mill. growing along an elevational gradient. For the first time, wood formation observations were used to validate weekly to annual stem radial increment simulations, while environmental measurements were used to assess the climatic constraints on turgor-driven growth. Model simulations matched the observed timing and dynamics of wood formation. Using the detailed model outputs, we identified a strict environmental regulation on stem growth (air temperature > 2°C and soil water potential > -0.6 MPa). Warmer and drier summers reduced the growth rate as a result of turgor limitation despite warmer temperatures being favourable for cambial activity. These findings suggest that turgor is a central driver of the forest carbon sink and should be considered in next-generation vegetation models, particularly in the context of global warming and increasing frequency of droughts.
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Affiliation(s)
- Richard L Peters
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, CH-8903, Switzerland
- Department of Environmental Sciences - Botany, Basel University, Schönbeinstrasse 6, Basel, CH-4056, Switzerland
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, B-9000, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, B-9000, Belgium
| | - Henri E Cuny
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, CH-8903, Switzerland
- Institut National de l'Information Géographique et Forestière (IGN), 1 rue des blanches terres, Champigneulles, 54115, France
| | - Dirk J W De Pauw
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, B-9000, Belgium
| | - David C Frank
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, CH-8903, Switzerland
- Laboratory of Tree-Ring Research, 1215 E. Lowell Street, Tucson, AZ, 8572, USA
| | - Marcus Schaub
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, CH-8903, Switzerland
| | | | - Antoine Cabon
- Joint Research Unit CTFC - AGROTECNIO, Solsona, E-25280, Spain
- CREAF, Cerdanyola del Vallès, Barcelona, E-08193, Spain
| | - Patrick Fonti
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, CH-8903, Switzerland
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42
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Tumajer J, Kašpar J, Kuželová H, Shishov VV, Tychkov II, Popkova MI, Vaganov EA, Treml V. Forward Modeling Reveals Multidecadal Trends in Cambial Kinetics and Phenology at Treeline. FRONTIERS IN PLANT SCIENCE 2021; 12:613643. [PMID: 33584770 PMCID: PMC7875878 DOI: 10.3389/fpls.2021.613643] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/06/2021] [Indexed: 05/02/2023]
Abstract
Significant alterations of cambial activity might be expected due to climate warming, leading to growing season extension and higher growth rates especially in cold-limited forests. However, assessment of climate-change-driven trends in intra-annual wood formation suffers from the lack of direct observations with a timespan exceeding a few years. We used the Vaganov-Shashkin process-based model to: (i) simulate daily resolved numbers of cambial and differentiating cells; and (ii) develop chronologies of the onset and termination of specific phases of cambial phenology during 1961-2017. We also determined the dominant climatic factor limiting cambial activity for each day. To asses intra-annual model validity, we used 8 years of direct xylogenesis monitoring from the treeline region of the Krkonoše Mts. (Czechia). The model exhibits high validity in case of spring phenological phases and a seasonal dynamics of tracheid production, but its precision declines for estimates of autumn phenological phases and growing season duration. The simulations reveal an increasing trend in the number of tracheids produced by cambium each year by 0.42 cells/year. Spring phenological phases (onset of cambial cell growth and tracheid enlargement) show significant shifts toward earlier occurrence in the year (for 0.28-0.34 days/year). In addition, there is a significant increase in simulated growth rates during entire growing season associated with the intra-annual redistribution of the dominant climatic controls over cambial activity. Results suggest that higher growth rates at treeline are driven by (i) temperature-stimulated intensification of spring cambial kinetics, and (ii) decoupling of summer growth rates from the limiting effect of low summer temperature due to higher frequency of climatically optimal days. Our results highlight that the cambial kinetics stimulation by increasing spring and summer temperatures and shifting spring phenology determine the recent growth trends of treeline ecosystems. Redistribution of individual climatic factors controlling cambial activity during the growing season questions the temporal stability of climatic signal of cold forest chronologies under ongoing climate change.
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Affiliation(s)
- Jan Tumajer
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
- Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, Germany
- *Correspondence: Jan Tumajer,
| | - Jakub Kašpar
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
| | - Hana Kuželová
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
| | - Vladimir V. Shishov
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
- Sukachev Institute of Forest SB RAS, Krasnoyarsk, Russia
| | - Ivan I. Tychkov
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
| | - Margarita I. Popkova
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
| | - Eugene A. Vaganov
- Sukachev Institute of Forest SB RAS, Krasnoyarsk, Russia
- Rectorate, Siberian Federal University, Krasnoyarsk, Russia
- Center for Forest Ecology and Productivity of the Russian Academy of Sciences, Moscow, Russia
| | - Václav Treml
- Department of Physical Geography and Geoecology, Faculty of Science, Charles University, Prague, Czechia
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43
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Eckes-Shephard AH, Tiavlovsky E, Chen Y, Fonti P, Friend AD. Direct response of tree growth to soil water and its implications for terrestrial carbon cycle modelling. GLOBAL CHANGE BIOLOGY 2021; 27:121-135. [PMID: 33065763 DOI: 10.1111/gcb.15397] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 06/11/2023]
Abstract
Wood growth constitutes the main process for long-term atmospheric carbon sequestration in vegetation. However, our understanding of the process of wood growth and its response to environmental drivers is limited. Current dynamic global vegetation models (DGVMs) are mainly photosynthesis-driven and thus do not explicitly include a direct environmental effect on tree growth. However, physiological evidence suggests that, to realistically model vegetation carbon allocation under increased climatic stressors, it is crucial to treat growth responses independently from photosynthesis. A plausible growth response function suitable for global simulations in DGVMs has been lacking. Here, we present the first soil water-growth response function and parameter range for deciduous and evergreen conifers. The response curve was calibrated against European larch and Norway spruce in a dry temperate forest in the Swiss Alps. We present a new data-driven approach based on a combination of tree ring width (TRW) records, growing season length and simulated subdaily soil hydrology to parameterize ring width increment simulations. We found that a simple linear response function, with an intercept at zero moisture stress, used in growth simulations reproduced 62.3% and 59.4% of observed TRW variability for larch and spruce respectively and, importantly, the response function slope was much steeper than literature values for soil moisture effects on photosynthesis and stomatal conductance. Specifically, we found stem growth stops at soil moisture potentials of -0.47 MPa for larch and -0.66 MPa for spruce, whereas photosynthesis in trees continues down to -1.2 MPa or lower, depending on species and measurement method. These results are strong evidence that the response functions of source and sink processes are indeed very different in trees, and need to be considered separately to correctly assess vegetation responses to environmental change. The results provide a parameterization for the explicit representation of growth responses to soil water in vegetation models.
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Affiliation(s)
| | | | - Yizhao Chen
- Department of Geography, University of Cambridge, Cambridge, UK
| | - Patrick Fonti
- Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
| | - Andrew D Friend
- Department of Geography, University of Cambridge, Cambridge, UK
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44
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Peters RL, Miranda JC, Schönbeck L, Nievergelt D, Fonti MV, Saurer M, Stritih A, Fonti P, Wermelinger B, von Arx G, Lehmann MM. Tree physiological monitoring of the 2018 larch budmoth outbreak: preference for leaf recovery and carbon storage over stem wood formation in Larix decidua. TREE PHYSIOLOGY 2020; 40:1697-1711. [PMID: 32722795 DOI: 10.1093/treephys/tpaa087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 05/17/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Insect defoliation impacts forest productivity worldwide, highlighting the relevance of plant-insect interactions. The larch budmoth (Zeiraphera griseana Hübner) is one of the most extensively studied defoliators, where numerous tree ring-based analyses on its host (Larix decidua Mill.) have aided in identifying outbreak dynamics over the past millennia. Yet, outbreaks have been widely absent after the early 1980s, and little is known about the in situ tree physiological responses and the allocation of carbon resources during and after defoliation. In summer 2018, we tracked an ongoing larch budmoth outbreak in a well-studied larch forest in the Swiss Alps. We performed biweekly monitoring on an affected and unaffected site using a unique combination of xylogenesis observations, measurements of non-structural carbohydrates, isotopic analysis of needle assimilates and ground-based and remote-sensed leaf trait observations. The budmoth induced a defoliation that lasted 40 days and could be detected by satellite observations. Soluble sugars significantly decreased in needles and stem phloem of the defoliated trees, while starch levels remained stable in the stem and root xylem compared to the control. Carbon and oxygen isotope ratios in needle assimilates indicated that neither photosynthetic assimilation rates nor stomatal conductance was different between sites before, during and after the outbreak. Defoliated trees ceased cell wall thickening 17 days earlier than unaffected trees, showing the earliest halt of ring formation recorded from 2007 untill 2013 and causing significant thinner cell walls, particularly in the latewood. No significant differences were found for cell enlargement rates and ring width. Our study revealed that an outbreak causes a downregulation of cell wall thickening first, while no starch is mobilized or leaf physiology is adjusted to compensate for the reduced carbon source due to defoliation. Our observations suggest that affected larch trees prioritize leaf recovery and carbon storage over wood biomass development.
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Affiliation(s)
- Richard L Peters
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
- Department of Plants and Crops, Faculty of Bioscience Engineering, Laboratory of Plant Ecology, Ghent University, Coupure links 653, Ghent B-9000, Belgium
| | - Jose Carlos Miranda
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
- Forest Genetics and Ecophysiology Research Group, School of Forestry Engineering, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, Madrid 28040, Spain
| | - Leonie Schönbeck
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
| | - Daniel Nievergelt
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
| | - Marina V Fonti
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
- Institute of Ecology and Geography, Siberian Federal University, 79 Svobodny pr., Krasnoyarsk 660041, Russia
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
| | - Ana Stritih
- ETH Zurich, Institute for Landscape and Spatial Development, Planning of Landscape and Urban Systems (PLUS), Stefano-Franscini Platz 5, Zürich 8093, Switzerland
- WSL Institute for Snow and Avalanche Research SLF, Flüelastrasse 11, Davos Dorf 7260, Switzerland
| | - Patrick Fonti
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
| | - Beat Wermelinger
- Forest Health and Biotic Interactions, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
| | - Georg von Arx
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
| | - Marco M Lehmann
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf CH-8903, Switzerland
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45
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Bose AK, Gessler A, Bolte A, Bottero A, Buras A, Cailleret M, Camarero JJ, Haeni M, Hereş A, Hevia A, Lévesque M, Linares JC, Martinez‐Vilalta J, Matías L, Menzel A, Sánchez‐Salguero R, Saurer M, Vennetier M, Ziche D, Rigling A. Growth and resilience responses of Scots pine to extreme droughts across Europe depend on predrought growth conditions. GLOBAL CHANGE BIOLOGY 2020; 26:4521-4537. [PMID: 32388882 PMCID: PMC7383776 DOI: 10.1111/gcb.15153] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 03/19/2020] [Accepted: 04/30/2020] [Indexed: 05/11/2023]
Abstract
Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees' phenotypic variability, which is, in turn, affected by long-term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree-level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree-, site-, and drought-related factors and their interactions driving the tree-level resilience to extreme droughts. We used a tree-ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid-elevation and low productivity sites from 1980-1999 to 2000-2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree-level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long-term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation.
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Affiliation(s)
- Arun K. Bose
- WSL Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
- Forestry and Wood Technology DisciplineKhulna UniversityKhulnaBangladesh
| | - Arthur Gessler
- WSL Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH ZurichZurichSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - Andreas Bolte
- Thünen Institute of Forest EcosystemsEberswaldeGermany
| | - Alessandra Bottero
- WSL Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - Allan Buras
- Land Surface‐Atmosphere InteractionsTechnische Universitat MünchenFreisingGermany
| | - Maxime Cailleret
- UMR RECOVER/Ecosystèmes Méditerranéens et RisquesINRAEAix‐en‐Provencecedex 5France
| | | | - Matthias Haeni
- WSL Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
| | - Ana‐Maria Hereş
- Department of Forest SciencesTransilvania University of BraşovBraşovRomania
- BC3 ‐ Basque Centre for Climate ChangeScientific Campus of the University of the Basque CountryLeioaSpain
| | - Andrea Hevia
- Departamento de Ciencias AgroforestalesUniversidad de HuelvaPalos de la FronteraSpain
| | | | - Juan C. Linares
- Depto. Sistemas Físicos, Químicos y NaturalesUniversidad Pablo de OlavideSevillaSpain
| | - Jordi Martinez‐Vilalta
- CREAFBellaterra (Cerdanyola del Vallès)Spain
- Universitat Autònoma de BarcelonaBellaterra (Cerdanyola del Vallès)Spain
| | - Luis Matías
- Departamento de Biología Vegetal y EcologíaFacultad de BiologíaUniversidad de SevillaSevillaSpain
| | - Annette Menzel
- EcoclimatologyTechnische Universität MünchenFreisingGermany
- Institute for Advanced StudyTechnische Universität MünchenGarchingGermany
| | - Raúl Sánchez‐Salguero
- Depto. Sistemas Físicos, Químicos y NaturalesUniversidad Pablo de OlavideSevillaSpain
| | - Matthias Saurer
- WSL Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
| | - Michel Vennetier
- UMR RECOVER/Ecosystèmes Méditerranéens et RisquesINRAEAix‐en‐Provencecedex 5France
| | - Daniel Ziche
- Thünen Institute of Forest EcosystemsEberswaldeGermany
- Faculty of Forest and EnvironmentEberswalde University for Sustainable DevelopmentEberswaldeGermany
| | - Andreas Rigling
- WSL Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH ZurichZurichSwitzerland
- SwissForestLabBirmensdorfSwitzerland
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46
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Castagneri D, Prendin AL, Peters RL, Carrer M, von Arx G, Fonti P. Long-Term Impacts of Defoliator Outbreaks on Larch Xylem Structure and Tree-Ring Biomass. FRONTIERS IN PLANT SCIENCE 2020; 11:1078. [PMID: 32765561 PMCID: PMC7378862 DOI: 10.3389/fpls.2020.01078] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 06/30/2020] [Indexed: 05/19/2023]
Abstract
Defoliator insects are a major disturbance agent in many forests worldwide. During outbreaks, they can strongly reduce photosynthetic carbon uptake and impact tree growth. In the Alps, larch budmoth (Zeiraphera diniana) outbreaks affect European larch (Larix decidua) radial growth over several years. However, immediate and legacy effects on xylem formation, structure, and functionality are still largely unknown. In this study, we aimed at assessing the impact of budmoth defoliations on larch xylem anatomical features and tree-ring structure. Analyses were performed in the Lötschental (Swiss Alps) within (1,900 m a.s.l.) and above (2,200 m a.s.l.) the optimum elevational range of larch budmoth. We investigated variability of xylem anatomical traits along century-long tree-ring series of larch (host) and Norway spruce (non-host) trees. We identified eight outbreaks affecting larch xylem anatomy during the 20th century, particularly at 1,900 m a.s.l. Tracheid number always showed a higher percent reduction than properties of individual cells. Cell lumen size was slightly reduced in the first 2-3 years of outbreaks, especially in the early part of the ring. The more carbon-demanding cell wall was thinned along the entire ring, but more evidently in the last part. Theoretical tree-ring hydraulic conductivity was reduced for several years (up to 6), mostly due to cell number decrease. Reduced cell wall area and cell number resulted in a strong reduction of the tree-ring biomass, especially in the first year of outbreak. Our study shows that, under carbon source limitations caused by natural defoliation, cell division is more impacted than wall thickening and cell enlargement (the least affected process). Consequences on both xylem hydraulic properties and tree-ring biomass should be considered when assessing long-term defoliator effects on xylem functioning, forest dynamics, and terrestrial carbon cycle.
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Affiliation(s)
- Daniele Castagneri
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- *Correspondence: Daniele Castagneri,
| | | | - Richard L. Peters
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Laboratory of Plant Ecology, Ghent University, Ghent, Belgium
| | - Marco Carrer
- Department TeSAF, Università degli Studi di Padova, Padova, Italy
| | - Georg von Arx
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Patrick Fonti
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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