Forest Ecosystems最新文献

Enhancing stem volume estimation for savanna species using variable-exponent taper equation and close-range photogrammetry

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-04-11 DOI: 10.1016/j.fecs.2025.100331

Finagnon Gabin Laly, Gilbert Atindogbe, Gbèdonou Michée Amos Sohou, Hospice Afouda Akpo, Noël Houédougbé Fonton

Stem volume estimation is crucial in forest ecology and management, particularly for timber harvesting strategies and carbon stock assessments. This study aimed to develop a variable-exponent taper equation specifically tailored to savanna tree species using close-range photogrammetry (CRP) data and to evaluate its performance against conventional volume equations for stem volume estimation. A dataset of 30 trees across five dominant savanna species was used to fit the taper model, which was validated using a separate dataset of 322 trees from 14 species. The results demonstrated significant improvements in volume estimation accuracy when using the taper equation. At the tree level, the root mean square error (RMSE) decreased by 47%, from 598 to 319 dm³, and the mean absolute bias (MAB) by 48%, from 328 to 172 dm³, compared to volume equations. Similarly, at the plot level, RMSE was reduced by 42% and MAB by 40%. The model performed well for species with regular forms. However, species with irregular tapers exhibited higher errors, reflecting the challenges of modeling stem forms of mixed species. The use of CRP proved valuable, providing high-resolution diameter measurements that improved model parameterization. This study underscores the importance of advanced data collection methods for enhancing taper model accuracy and suggests that further species-specific adjustments are needed to improve performance for species with irregular forms. The findings support the broader application of taper equations for improving stem volume estimates in savanna ecosystems, contributing to better forest management and resource monitoring practices.

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引用次数: 0

How to determine the leaf area index (LAI) of forests: A comparison of forest inventory versus satellite-driven estimates

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-04-11 DOI: 10.1016/j.fecs.2025.100332

Muhammed Sinan, Hubert Hasenauer

Leaf area index (LAI) is a key measure of forest stand physiology and biomass production, and is essential within ecosystem modeling. There are two common approaches to obtaining LAI: (i) terrestrial forest inventory-based “bottom–up”, and (ii) satellite-based “top–down” techniques. The purpose of this study is to compare terrestrial LAI from allometric functions applied to more than 30,000 trees of the Austrian National Forest Inventory (NFI) vs. satellite-based LAI estimates obtained from moderate resolution imaging spectroradiometer (MODIS) and Sentinel (Sentinel-3 TOC reflectance and PROBA-V) data across Austrian forests. We analyzed a satellite pixel-to-plot aggregation and obtained the full inventory data set for the LAI comparison. The results suggest that terrestrial vs. satellite (MODIS and Sentinel) driven LAI estimates are consistent, but (i) the variation of the terrestrial forest inventory LAI is larger vs. the pixel average LAI from satellite data, and (ii) any satellite LAI estimation needs a forest stand density correction if the crown competition factor (CCF), a measure for stand density, is < 250 to avoid an overestimation in LAI.

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引用次数: 0

Greening of Eurasia's center driven by low-latitude climate warming

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-04-11 DOI: 10.1016/j.fecs.2025.100330

Shijie Wang , Feng Chen , Youping Chen , Max C.A. Torbenson , Jan Esper , Xiaoen Zhao , Mao Hu , Heli Zhang , Weipeng Yue , Honghua Cao

Central Asia, located in the innermost part of the Eurasian continent, has experienced “warming and humidification” in recent decades, with potentially important implications for tree growth in alpine forests, which are critical for regional water reserves. We use nested principal component analysis to assess tree radial growth patterns and reveal significant positive trends since the 20th century across Central Asian alpine forests (0.076 per decade during 1900–2021, p = 0.003). Regional hydroclimatic variations affect the greening of these alpine forests, especially with extreme droughts being the most damaging. Growth acceleration is driven by low-latitude warming, which enhances regional temperatures and precipitation. The warming ocean centers alter atmospheric circulation patterns, leading to more moisture being transported to the Central Asian alpine forests, thereby increasing regional precipitation and promoting tree growth. Our model projections indicate that growth rates will continue to rise in the future. However, unprecedented warming may eventually lead to growth deterioration if negative effects, such as insufficient precipitation, occur due to breakdown signs of positive feedback mechanisms, such as moisture transport driven by low-latitude warming. Our study highlights the beneficial, but not unlimited, influences of climate warming on tree growth in Central Asian alpine forests, with implications for the sustainability of water resources. However, as urban and agricultural demands escalate, a holistic, long-term perspective is recommended to mitigate the adverse effects of temperature increases.

{"title":"Greening of Eurasia's center driven by low-latitude climate warming","authors":"Shijie Wang , Feng Chen , Youping Chen , Max C.A. Torbenson , Jan Esper , Xiaoen Zhao , Mao Hu , Heli Zhang , Weipeng Yue , Honghua Cao","doi":"10.1016/j.fecs.2025.100330","DOIUrl":"10.1016/j.fecs.2025.100330","url":null,"abstract":"<div><div>Central Asia, located in the innermost part of the Eurasian continent, has experienced “warming and humidification” in recent decades, with potentially important implications for tree growth in alpine forests, which are critical for regional water reserves. We use nested principal component analysis to assess tree radial growth patterns and reveal significant positive trends since the 20th century across Central Asian alpine forests (0.076 per decade during 1900–2021, <em>p</em> = 0.003). Regional hydroclimatic variations affect the greening of these alpine forests, especially with extreme droughts being the most damaging. Growth acceleration is driven by low-latitude warming, which enhances regional temperatures and precipitation. The warming ocean centers alter atmospheric circulation patterns, leading to more moisture being transported to the Central Asian alpine forests, thereby increasing regional precipitation and promoting tree growth. Our model projections indicate that growth rates will continue to rise in the future. However, unprecedented warming may eventually lead to growth deterioration if negative effects, such as insufficient precipitation, occur due to breakdown signs of positive feedback mechanisms, such as moisture transport driven by low-latitude warming. Our study highlights the beneficial, but not unlimited, influences of climate warming on tree growth in Central Asian alpine forests, with implications for the sustainability of water resources. However, as urban and agricultural demands escalate, a holistic, long-term perspective is recommended to mitigate the adverse effects of temperature increases.</div></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"13 ","pages":"Article 100330"},"PeriodicalIF":3.8,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143854682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microbial genomic traits and mineral protection jointly regulate the temperature sensitivity of soil carbon decomposition in boreal forests

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-04-11 DOI: 10.1016/j.fecs.2025.100333

Xinyi Zhang , Zhenglong Lu , Shuang Yin , Xuesen Pang , Yufan Liang , Zhenghu Zhou

Soil organic carbon (SOC) decomposition in high-latitude boreal forests exhibits heightened sensitivity to climate change. However, a comprehensive understanding of the underlying drivers governing soil microbial decomposition responses to warming in these ecosystems remains elusive, especially regarding the roles of mineral protection and microbial genomic traits. In this study, we examined the temperature sensitivity (Q₁₀) and minimum temperature (T_min) of soil microbial respiration across a latitudinal gradient in China's boreal forests. The potential regulators, including climatic factors, soil physicochemical properties, substrate quality, mineral protection, and microbial genomic traits, were also synchronously measured. The results showed a positive correlation between Q₁₀ and T_min, i.e., greater microbial adaptability to low temperatures is associated with lower microbial sensitivity to increasing temperatures. Boreal forest soil with stronger mineral protection exhibited a higher Q₁₀. In addition, microbial communities characterized by a higher abundance of coding genes demonstrated significantly lower Q₁₀ and reduced T_min. These results collectively highlight the pivotal roles of mineral protection and microbial genomic traits in shaping the biogeographic pattern of Q₁₀ across boreal forests.

{"title":"Microbial genomic traits and mineral protection jointly regulate the temperature sensitivity of soil carbon decomposition in boreal forests","authors":"Xinyi Zhang , Zhenglong Lu , Shuang Yin , Xuesen Pang , Yufan Liang , Zhenghu Zhou","doi":"10.1016/j.fecs.2025.100333","DOIUrl":"10.1016/j.fecs.2025.100333","url":null,"abstract":"<div><div>Soil organic carbon (SOC) decomposition in high-latitude boreal forests exhibits heightened sensitivity to climate change. However, a comprehensive understanding of the underlying drivers governing soil microbial decomposition responses to warming in these ecosystems remains elusive, especially regarding the roles of mineral protection and microbial genomic traits. In this study, we examined the temperature sensitivity (<em>Q</em><sub>10</sub>) and minimum temperature (<em>T</em><sub>min</sub>) of soil microbial respiration across a latitudinal gradient in China's boreal forests. The potential regulators, including climatic factors, soil physicochemical properties, substrate quality, mineral protection, and microbial genomic traits, were also synchronously measured. The results showed a positive correlation between <em>Q</em><sub>10</sub> and <em>T</em><sub>min</sub>, i.e., greater microbial adaptability to low temperatures is associated with lower microbial sensitivity to increasing temperatures. Boreal forest soil with stronger mineral protection exhibited a higher <em>Q</em><sub>10</sub>. In addition, microbial communities characterized by a higher abundance of coding genes demonstrated significantly lower <em>Q</em><sub>10</sub> and reduced <em>T</em><sub>min</sub>. These results collectively highlight the pivotal roles of mineral protection and microbial genomic traits in shaping the biogeographic pattern of <em>Q</em><sub>10</sub> across boreal forests.</div></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"13 ","pages":"Article 100333"},"PeriodicalIF":3.8,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bark beetle-induced salvage logging cycle is caused by weather patterns linked to the NAO and solar cycle in Central Europe

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-04-05 DOI: 10.1016/j.fecs.2025.100328

Václav Šimůnek , Zdeněk Vacek , Stanislav Vacek , Michal Švanda , Vilém Podrázský , Jan Cukor , Josef Gallo , Petr Zahradník

Central Europe has faced major disasters causing fluctuations in salvage logging. These events, driven by natural or human factors, have damaged forest. Climate change is a key factor that cyclically affects these patterns. These forest disasters cause billions in financial losses due to lower wood prices and quality, but their regular cycles are poorly understood. The objective of this study is to conduct a comprehensive analysis of salvage logging in Austria, Czechia, and Slovakia. Analyses indicate an upward trend in bark beetle-induced logging over the past five decades, with a notable surge in salvage logging in recent years. Cyclical fluctuations linked to solar activity represented by total solar irradiance (TSI) have been observed across the data. Higher TSI reduces beetle-induced logging to 3%–5%, while lower TSI increases it to 17%–24% near the solar minimum. An increase to higher seasonal temperature and a decrease to low precipitation one year before leads to a peak in beetle-induced logging, caused by drought. Seasonal precipitation and the North Atlantic Oscillation (NAO) have less impact, but higher precipitation is seen one year after the peak in bark-beetle logging. Droughts regularly occur one year before calamity peaks, confirmed by the Standardized Precipitation Evapotranspiration Index (SPEI). Harvests caused by wind and snow events have shorter cycles compared to the longer and more regular cycles of bark beetle-induced harvest. Common wavelet power spectrum analysis revealed a consistent 9- to 12-year cycle across all data sets. Solar cycle significantly impacts forest management through the NAO, precipitation, and temperature. The study suggests the potential for utilizing cyclical relationships in calamity prediction and more effective forest management in Central Europe.

{"title":"Bark beetle-induced salvage logging cycle is caused by weather patterns linked to the NAO and solar cycle in Central Europe","authors":"Václav Šimůnek , Zdeněk Vacek , Stanislav Vacek , Michal Švanda , Vilém Podrázský , Jan Cukor , Josef Gallo , Petr Zahradník","doi":"10.1016/j.fecs.2025.100328","DOIUrl":"10.1016/j.fecs.2025.100328","url":null,"abstract":"<div><div>Central Europe has faced major disasters causing fluctuations in salvage logging. These events, driven by natural or human factors, have damaged forest. Climate change is a key factor that cyclically affects these patterns. These forest disasters cause billions in financial losses due to lower wood prices and quality, but their regular cycles are poorly understood. The objective of this study is to conduct a comprehensive analysis of salvage logging in Austria, Czechia, and Slovakia. Analyses indicate an upward trend in bark beetle-induced logging over the past five decades, with a notable surge in salvage logging in recent years. Cyclical fluctuations linked to solar activity represented by total solar irradiance (TSI) have been observed across the data. Higher TSI reduces beetle-induced logging to 3%–5%, while lower TSI increases it to 17%–24% near the solar minimum. An increase to higher seasonal temperature and a decrease to low precipitation one year before leads to a peak in beetle-induced logging, caused by drought. Seasonal precipitation and the North Atlantic Oscillation (NAO) have less impact, but higher precipitation is seen one year after the peak in bark-beetle logging. Droughts regularly occur one year before calamity peaks, confirmed by the Standardized Precipitation Evapotranspiration Index (SPEI). Harvests caused by wind and snow events have shorter cycles compared to the longer and more regular cycles of bark beetle-induced harvest. Common wavelet power spectrum analysis revealed a consistent 9- to 12-year cycle across all data sets. Solar cycle significantly impacts forest management through the NAO, precipitation, and temperature. The study suggests the potential for utilizing cyclical relationships in calamity prediction and more effective forest management in Central Europe.</div></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"13 ","pages":"Article 100328"},"PeriodicalIF":3.8,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Drought limits tree growth more than greenness and reproduction: insights from five case studies in Spain

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-04-04 DOI: 10.1016/j.fecs.2025.100329

J. Julio Camarero , Álvaro Rubio-Cuadrado , Ester González de Andrés , Cristina Valeriano , Manuel Pizarro , J. Bosco Imbert , Yueh-Hsin Lo , Juan A. Blanco

Droughts impact forests by influencing various processes such as canopy greenness, tree growth, and reproduction, but most studies have only examined a few of these processes. More comprehensive assessments of forest responses to climate variability and water shortages are needed to improve forecasts of post-drought dynamics. Iberian forests are well-suited for evaluating these effects because they experience diverse climatic conditions and are dominated by various conifer and broadleaf species, many of which exhibit masting. We assessed how greenness, evaluated using the normalized difference vegetation index (NDVI), tree radial growth, and seed or cone production responded to drought in five tree species (three conifers: silver fir (Abies alba), Scots pine (Pinus sylvestris), and stone pine (Pinus pinea); two broadleaves: European beech (Fagus sylvatica) and holm oak (Quercus ilex) inhabiting sites with different aridity. We correlated these data with the standardized precipitation evapotranspiration index (SPEI) using the climate window analysis (climwin) package, which identifies the most relevant climate window. Drought constrained growth more than greenness and seed or cone production. Dry conditions led to high seed or cone production in species found in cool, moist sites (silver fir, beech, and Scots pine). We also found negative associations of cone production with summer SPEI in the drought-tolerant stone pine, which showed lagged growth−cone negative correlations. However, in the seasonally dry holm oak forests, severe droughts constrained both growth and acorn production, leading to a positive correlation between these variables. Drought impacts on greenness, growth, seed, and cone production depended on species phenology and site aridity. A negative correlation between growth and reproduction does not necessarily indicate trade-offs, as both may be influenced by similar climatic factors.

{"title":"Drought limits tree growth more than greenness and reproduction: insights from five case studies in Spain","authors":"J. Julio Camarero , Álvaro Rubio-Cuadrado , Ester González de Andrés , Cristina Valeriano , Manuel Pizarro , J. Bosco Imbert , Yueh-Hsin Lo , Juan A. Blanco","doi":"10.1016/j.fecs.2025.100329","DOIUrl":"10.1016/j.fecs.2025.100329","url":null,"abstract":"<div><div>Droughts impact forests by influencing various processes such as canopy greenness, tree growth, and reproduction, but most studies have only examined a few of these processes. More comprehensive assessments of forest responses to climate variability and water shortages are needed to improve forecasts of post-drought dynamics. Iberian forests are well-suited for evaluating these effects because they experience diverse climatic conditions and are dominated by various conifer and broadleaf species, many of which exhibit masting. We assessed how greenness, evaluated using the normalized difference vegetation index (NDVI), tree radial growth, and seed or cone production responded to drought in five tree species (three conifers: silver fir (<em>Abies alba</em>), Scots pine (<em>Pinus sylvestris</em>), and stone pine (<em>Pinus pinea</em>); two broadleaves: European beech (<em>Fagus sylvatica</em>) and holm oak (<em>Quercus ilex</em>) inhabiting sites with different aridity. We correlated these data with the standardized precipitation evapotranspiration index (SPEI) using the climate window analysis (<em>climwin</em>) package, which identifies the most relevant climate window. Drought constrained growth more than greenness and seed or cone production. Dry conditions led to high seed or cone production in species found in cool, moist sites (silver fir, beech, and Scots pine). We also found negative associations of cone production with summer SPEI in the drought-tolerant stone pine, which showed lagged growth−cone negative correlations. However, in the seasonally dry holm oak forests, severe droughts constrained both growth and acorn production, leading to a positive correlation between these variables. Drought impacts on greenness, growth, seed, and cone production depended on species phenology and site aridity. A negative correlation between growth and reproduction does not necessarily indicate trade-offs, as both may be influenced by similar climatic factors.</div></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"13 ","pages":"Article 100329"},"PeriodicalIF":3.8,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143815219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adaptive optimisation of the management of Korean pine plantation

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-03-30 DOI: 10.1016/j.fecs.2025.100326

Qianping Tong , Xingji Jin , Timo Pukkala , Lihu Dong , Fengri Li

Forest management planning faces uncertainties regarding future timber prices, tree growth, and survival. Future seed production is an additional source of uncertainty in Korean pine stands managed for the joint production of timber and edible seeds. Modern forest planning uses optimisation to determine the best possible cutting schedule. Optimisation can accommodate uncertainty by using decision rules for adaptive forest management instead of optimising cutting years and intensities. In this study, we optimised two adaptive decision rules for managing Korean pine plantations for the joint production of timber and pinecones when timber prices, tree growth, and seed production are stochastic. The first rule indicated the minimum price to sell timber, i.e., the reservation price, as a function of the mean tree diameter and stand basal area. The second adaptive rule expressed the mean tree diameter at which cutting is optimal as a function of timber price and stand basal area. Both decision rules resulted in nearly the same mean net present value when the optimised rule was applied to 100 stochastic scenarios for future timber prices, tree growth, and seed production. The net present values were over 20% higher than those for the deterministically optimised cutting schedules under the same scenarios. Therefore, the expected economic gain from switching from deterministic to adaptive stochastic optimisation was at least 20%. The cutting years of the adaptive optima were frequently later than those indicated by the deterministic optima, and optimal adaptive harvesting often involved waiting for high timber prices. The minimum price or minimum mean diameter to sell timber was higher when the income from seeds was considered in the optimisation. The cuttings were later, and the rotations were longer in the joint production of timber and pinecones than in timber production alone.

森林管理规划面临着未来木材价格、树木生长和存活率方面的不确定性。未来的种子产量也是韩国松林管理中的一个不确定因素，因为韩国松林既要生产木材，又要生产可食用的种子。现代森林规划采用优化方法来确定最佳的砍伐计划。优化可以通过使用适应性森林管理的决策规则来适应不确定性，而不是优化砍伐年限和强度。在这项研究中，我们优化了两个适应性决策规则，用于管理韩国松树人工林，在木材价格、树木生长和种子生产都是随机的情况下，共同生产木材和松果。第一条规则表示出售木材的最低价格，即保留价，它是平均树径和林分基部面积的函数。第二种自适应规则将伐木最佳的平均树径表示为木材价格和林分基部面积的函数。将优化规则应用于未来木材价格、树木生长和种子产量的 100 种随机情景时，两种决策规则产生的平均净现值几乎相同。在相同情况下，净现值比确定性优化砍伐计划高出 20% 以上。因此，从确定性优化到自适应随机优化的预期经济收益至少为 20%。自适应优化的砍伐年份往往晚于确定性优化的砍伐年份，自适应优化砍伐往往需要等待高木材价格。在优化过程中考虑种子收入时，出售木材的最低价格或最小平均直径会更高。与单独生产木材相比，联合生产木材和松果的伐木时间更晚，轮伐期更长。

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引用次数: 0

Long-term leaf nitrogen and phosphorus dynamics and drivers in China's forests under global change

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-03-27 DOI: 10.1016/j.fecs.2025.100325

Chenxi Li , Honglin He , Xinyu Zhang , Xiaoli Ren , Liang Shi , Li Zhang , Qian Xu , Mengyu Zhang , Yonghong Zhang

The leaf nitrogen (N) to phosphorus (P) ratio (N:P) is a critical indicator of nutrient dynamics and ecosystem function. Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability. However, limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones. Using long-term monitoring data from the Chinese Ecosystem Research Network (CERN), we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions, and identified the underlying mechanisms driving these changes. For both regions combined, leaf P concentration of the 50 dominant tree species decreased (20.6%), whereas leaf N:P increased (52.0%) from 2005 to 2020. Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species, respectively. The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests, where global change factors and soil nutrients explained 68% of leaf N:P variation. The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time, and elevated temperature and CO₂ levels, coupled with decreased soil available P concentrations, appear to be the main factors driving long-term leaf N:P increases in these forests. Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management.

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引用次数: 0

Endemic threatened tree species in the Mediterranean forests of central Chile are highly sensitive to ENSO-driven water availability and drought

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-03-24 DOI: 10.1016/j.fecs.2025.100324

Tania Gipoulou-Zúñiga , Moisés Rojas-Badilla , Carlos LeQuesne , Vicente Rozas

The Mediterranean region in central Chile is experiencing a significant decrease in precipitation due to climate change and the dynamics of the El Niño Southern Oscillation (ENSO). Droughts have increased in recent decades, with the most severe and longest drought of the last millennium occurring since 2010 in central Chile. The impact of ongoing water scarcity is leading to significant drought-related declines in tree growth and forest dieback in the Mediterranean region. A deep understanding of how tree species respond to climate is crucial to accurately predict how forests will respond to climate change. We examined the growth responses to climate of three endemic and threatened tree species of the Mediterranean forests of central Chile, Nothofagus macrocarpa, Cryptocarya alba and Persea lingue, in a protected area. We observed that the growth of all three species was highly dependent on water availability and ENSO, and that the evergreen species C. alba and P. lingue increased their sensitivity to hydroclimate more than the deciduous species N. macrocarpa. These relationships were consistent across much of southern South America, highlighting the dependence of these species on water availability at large geographic scales. We found that there is a relationship between local water availability and ENSO that has intensified temporally and expanded geographically in recent decades. The xerophyllous species C. alba showed greater resistance and increasing resilience to severe droughts, while P. lingue and N. macrocarpa showed greater growth decline during droughts, possibly due to their preference for wetter environments. Our results highlight the crucial role of ENSO-driven water availability and drought in limiting tree growth and threatening the conservation of Mediterranean forests in central Chile.

{"title":"Endemic threatened tree species in the Mediterranean forests of central Chile are highly sensitive to ENSO-driven water availability and drought","authors":"Tania Gipoulou-Zúñiga , Moisés Rojas-Badilla , Carlos LeQuesne , Vicente Rozas","doi":"10.1016/j.fecs.2025.100324","DOIUrl":"10.1016/j.fecs.2025.100324","url":null,"abstract":"<div><div>The Mediterranean region in central Chile is experiencing a significant decrease in precipitation due to climate change and the dynamics of the El Niño Southern Oscillation (ENSO). Droughts have increased in recent decades, with the most severe and longest drought of the last millennium occurring since 2010 in central Chile. The impact of ongoing water scarcity is leading to significant drought-related declines in tree growth and forest dieback in the Mediterranean region. A deep understanding of how tree species respond to climate is crucial to accurately predict how forests will respond to climate change. We examined the growth responses to climate of three endemic and threatened tree species of the Mediterranean forests of central Chile, <em>Nothofagus macrocarpa</em>, <em>Cryptocarya alba</em> and <em>Persea lingue</em>, in a protected area. We observed that the growth of all three species was highly dependent on water availability and ENSO, and that the evergreen species <em>C</em>. <em>alba</em> and <em>P</em>. <em>lingue</em> increased their sensitivity to hydroclimate more than the deciduous species <em>N</em>. <em>macrocarpa</em>. These relationships were consistent across much of southern South America, highlighting the dependence of these species on water availability at large geographic scales. We found that there is a relationship between local water availability and ENSO that has intensified temporally and expanded geographically in recent decades. The xerophyllous species <em>C</em>. <em>alba</em> showed greater resistance and increasing resilience to severe droughts, while <em>P</em>. <em>lingue</em> and <em>N</em>. <em>macrocarpa</em> showed greater growth decline during droughts, possibly due to their preference for wetter environments. Our results highlight the crucial role of ENSO-driven water availability and drought in limiting tree growth and threatening the conservation of Mediterranean forests in central Chile.</div></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"13 ","pages":"Article 100324"},"PeriodicalIF":3.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nonlinear multilevel seemingly unrelated height-diameter and crown length mixed-effects models for the southern Transylvanian forests, Romania

IF 3.8 1区农林科学 Q1 FORESTRY

Forest Ecosystems

Pub Date : 2025-03-11 DOI: 10.1016/j.fecs.2025.100322

Albert Ciceu , Ştefan Leca , Ovidiu Badea , Lauri Mehtätalo

In this study, we used an extensive sampling network established in central Romania to develop tree height and crown length models. Our analysis included more than 18,000 tree measurements from five different species. Instead of building univariate models for each response variable, we employed a multivariate approach using seemingly unrelated mixed-effects models. These models incorporated variables related to species mixture, tree and stand size, competition, and stand structure. With the inclusion of additional variables in the multivariate seemingly unrelated mixed-effects models, the accuracy of the height prediction models improved by over 10% for all species, whereas the improvement in the crown length models was considerably smaller. Our findings indicate that trees in mixed stands tend to have shorter heights but longer crowns than those in pure stands. We also observed that trees in homogeneous stand structures have shorter crown lengths than those in heterogeneous stands. By employing a multivariate mixed-effects modelling framework, we were able to perform cross-model random-effect predictions, leading to a significant increase in accuracy when both responses were used to calibrate the model. In contrast, the improvement in accuracy was marginal when only height was used for calibration. We demonstrate how multivariate mixed-effects models can be effectively used to develop multi-response allometric models that can be easily calibrated with a limited number of observations while simultaneously achieving better-aligned projections.

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引用次数: 0