Introduction Drought-associated tree mortality has been increasing worldwide since the last decades, impacting structure and functioning of forest ecosystems, with implications for energy, carbon and water fluxes. However, the understanding of the individual vulnerability to drought-induced mortality is still limited. Methods We aimed to identify the factors that triggered the mortality of the widely distributed Pinus sylvestris L. in an extensive forest area in central Spain. We compared radial growth patterns in pairs of alive and recently dead individuals that co-occur in close proximity and present similar age and size, thereby isolating the effects of size and environment from the mortality process. Temporal dynamics of growth, growth synchrony, and growth sensitivity to water availability (precipitation minus potential evapotranspiration) were compared between alive and recently dead trees. Results and discussion Over the last 50 years, although we did not detect significant differences in growth between alive and dead trees, an increase in the growth synchrony and sensitivity to water availability (i.e. slope of the climatic water balance in the growth model) was observed in all trees as drought intensity increased. 20 years before mortality, dead individuals showed lower growth synchrony and growth sensitivity to water availability than alive ones, without significant differences in growth. Recorded reduction in growth synchrony and growth sensitivity to water availability in dead trees suggests a decoupling between tree growth and climate, which could increase the risk of hydraulic failure and/or carbon starvation under increasingly arid conditions. Thus, the use of reduced growth sensitivity to water availability as potential early-warning signal of tree mortality, together with reduced growth synchrony, should be further explored, particularly in pine species in seasonally dry areas.
{"title":"Reduced growth sensitivity to water availability as potential indicator of drought-induced tree mortality risk in a Mediterranean Pinus sylvestris L. forest","authors":"Asier Herrero, Raquel González-Gascueña, Patricia González-Díaz, Paloma Ruiz-Benito, Enrique Andivia","doi":"10.3389/ffgc.2023.1249246","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1249246","url":null,"abstract":"Introduction Drought-associated tree mortality has been increasing worldwide since the last decades, impacting structure and functioning of forest ecosystems, with implications for energy, carbon and water fluxes. However, the understanding of the individual vulnerability to drought-induced mortality is still limited. Methods We aimed to identify the factors that triggered the mortality of the widely distributed Pinus sylvestris L. in an extensive forest area in central Spain. We compared radial growth patterns in pairs of alive and recently dead individuals that co-occur in close proximity and present similar age and size, thereby isolating the effects of size and environment from the mortality process. Temporal dynamics of growth, growth synchrony, and growth sensitivity to water availability (precipitation minus potential evapotranspiration) were compared between alive and recently dead trees. Results and discussion Over the last 50 years, although we did not detect significant differences in growth between alive and dead trees, an increase in the growth synchrony and sensitivity to water availability (i.e. slope of the climatic water balance in the growth model) was observed in all trees as drought intensity increased. 20 years before mortality, dead individuals showed lower growth synchrony and growth sensitivity to water availability than alive ones, without significant differences in growth. Recorded reduction in growth synchrony and growth sensitivity to water availability in dead trees suggests a decoupling between tree growth and climate, which could increase the risk of hydraulic failure and/or carbon starvation under increasingly arid conditions. Thus, the use of reduced growth sensitivity to water availability as potential early-warning signal of tree mortality, together with reduced growth synchrony, should be further explored, particularly in pine species in seasonally dry areas.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":" 30","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135293477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-08DOI: 10.3389/ffgc.2023.1266413
Matthew P. Thompson, John F. Carriger
Assessing the effectiveness and measuring the performance of fuel treatments and other wildfire risk mitigation efforts are challenging endeavors. Perhaps the most complicated is quantifying avoided impacts. In this study, we show how probabilistic counterfactual analysis can help with performance evaluation. We borrow insights from the disaster risk mitigation and climate event attribution literature to illustrate a counterfactual framework and provide examples using ensemble wildfire simulations. Specifically, we reanalyze previously published fire simulation data from fire-prone landscapes in New Mexico, USA, and show applications for post-event analysis as well as pre-event evaluation of fuel treatment scenarios. This approach found that treated landscapes likely would have reduced fire risk compared to the untreated scenarios. To conclude, we offer ideas for future expansions in theory and methods.
{"title":"Avoided wildfire impact modeling with counterfactual probabilistic analysis","authors":"Matthew P. Thompson, John F. Carriger","doi":"10.3389/ffgc.2023.1266413","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1266413","url":null,"abstract":"Assessing the effectiveness and measuring the performance of fuel treatments and other wildfire risk mitigation efforts are challenging endeavors. Perhaps the most complicated is quantifying avoided impacts. In this study, we show how probabilistic counterfactual analysis can help with performance evaluation. We borrow insights from the disaster risk mitigation and climate event attribution literature to illustrate a counterfactual framework and provide examples using ensemble wildfire simulations. Specifically, we reanalyze previously published fire simulation data from fire-prone landscapes in New Mexico, USA, and show applications for post-event analysis as well as pre-event evaluation of fuel treatment scenarios. This approach found that treated landscapes likely would have reduced fire risk compared to the untreated scenarios. To conclude, we offer ideas for future expansions in theory and methods.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"354 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135392315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-08DOI: 10.3389/ffgc.2023.1098901
Arildo Dias, Shaya Van Houdt, Katrin Meschin, Katherine Von Stackelberg, Mari-Liis Bago, Lauren Baldarelli, Karen Gonzalez Downs, Mariel Luuk, Timothée Delubac, Elio Bottagisio, Kuno Kasak, Atilcan Kebabci, Oliver Levers, Igor Miilvee, Jana Paju-Hamburg, Rémy Poncet, Massimiliano Sanfilippo, Jüri Sildam, Dmitri Stepanov, Donalda Karnauskaite
Introduction An unprecedented amount of Earth Observations and in-situ data has become available in recent decades, opening up the possibility of developing scalable and practical solutions to assess and monitor ecosystems across the globe. Essential Biodiversity Variables are an example of the integration between Earth Observations and in-situ data for monitoring biodiversity and ecosystem integrity, with applicability to assess and monitor ecosystem structure, function, and composition. However, studies have yet to explore how such metrics can be organized in an effective workflow to create a composite Ecosystem Integrity Index and differentiate between local plots at the global scale. Methods Using available Essential Biodiversity Variables, we present and test a framework to assess and monitor forest ecosystem integrity at the global scale. We first defined the theoretical framework used to develop the workflow. We then measured ecosystem integrity across 333 forest plots of 5 km 2 . We classified the plots across the globe using two main categories of ecosystem integrity (Top and Down) defined using different Essential Biodiversity Variables. Results and discussion: We found that ecosystem integrity was significantly higher in forest plots located in more intact areas than in forest plots with higher disturbance. On average, intact forests had an Ecosystem Integrity Index score of 5.88 (CI: 5.53–6.23), whereas higher disturbance lowered the average to 4.97 (CI: 4.67–5.26). Knowing the state and changes in forest ecosystem integrity may help to deliver funding to priority areas that would benefit from mitigation strategies targeting climate change and biodiversity loss. This study may further provide decision- and policymakers with relevant information about the effectiveness of forest management and policies concerning forests. Our proposed method provides a flexible and scalable solution that facilitates the integration of essential biodiversity variables to monitor forest ecosystems.
{"title":"Using essential biodiversity variables to assess forest ecosystem integrity","authors":"Arildo Dias, Shaya Van Houdt, Katrin Meschin, Katherine Von Stackelberg, Mari-Liis Bago, Lauren Baldarelli, Karen Gonzalez Downs, Mariel Luuk, Timothée Delubac, Elio Bottagisio, Kuno Kasak, Atilcan Kebabci, Oliver Levers, Igor Miilvee, Jana Paju-Hamburg, Rémy Poncet, Massimiliano Sanfilippo, Jüri Sildam, Dmitri Stepanov, Donalda Karnauskaite","doi":"10.3389/ffgc.2023.1098901","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1098901","url":null,"abstract":"Introduction An unprecedented amount of Earth Observations and in-situ data has become available in recent decades, opening up the possibility of developing scalable and practical solutions to assess and monitor ecosystems across the globe. Essential Biodiversity Variables are an example of the integration between Earth Observations and in-situ data for monitoring biodiversity and ecosystem integrity, with applicability to assess and monitor ecosystem structure, function, and composition. However, studies have yet to explore how such metrics can be organized in an effective workflow to create a composite Ecosystem Integrity Index and differentiate between local plots at the global scale. Methods Using available Essential Biodiversity Variables, we present and test a framework to assess and monitor forest ecosystem integrity at the global scale. We first defined the theoretical framework used to develop the workflow. We then measured ecosystem integrity across 333 forest plots of 5 km 2 . We classified the plots across the globe using two main categories of ecosystem integrity (Top and Down) defined using different Essential Biodiversity Variables. Results and discussion: We found that ecosystem integrity was significantly higher in forest plots located in more intact areas than in forest plots with higher disturbance. On average, intact forests had an Ecosystem Integrity Index score of 5.88 (CI: 5.53–6.23), whereas higher disturbance lowered the average to 4.97 (CI: 4.67–5.26). Knowing the state and changes in forest ecosystem integrity may help to deliver funding to priority areas that would benefit from mitigation strategies targeting climate change and biodiversity loss. This study may further provide decision- and policymakers with relevant information about the effectiveness of forest management and policies concerning forests. Our proposed method provides a flexible and scalable solution that facilitates the integration of essential biodiversity variables to monitor forest ecosystems.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"43 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135429840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-07DOI: 10.3389/ffgc.2023.1259010
Chad C. Papa, Kendall DeLyser, Kylie Clay, Daphna Gadoth-Goodman, Lauren Cooper, Werner A. Kurz, Michael Magnan, Todd Ontl
State and local governments are increasingly interested in understanding the role forests and harvested wood products play in regional carbon sinks and storage, their potential contributions to state-level greenhouse gas (GHG) reductions, and the interactions between GHG reduction goals and potential economic opportunities. We used empirically driven process-based forest carbon dynamics and harvested wood product models in a systems-based approach to project the carbon impacts of various forest management and wood utilization activities in Maryland and Pennsylvania from 2007 to 2100. To quantify state-wide forest carbon dynamics, we integrated forest inventory data, harvest and management activity data, and remotely-sensed metrics of land-use change and natural forest disturbances within a participatory modeling approach. We accounted for net GHG emissions across (1) forest ecosystems (2) harvested wood products, (3) substitution benefits from wood product utilization, and (4) leakage associated with reduced in-state harvesting activities. Based on state agency partner input, a total of 15 management scenarios were modeled for Maryland and 13 for Pennsylvania, along with two climate change impact scenarios and two bioenergy scenarios for each state. Our findings show that both strategic forest management and wood utilization can provide substantial climate change mitigation potential relative to business-as-usual practices, increasing the forest C sink by 29% in Maryland and 38% in Pennsylvania by 2030 without disrupting timber supplies. Key climate-smart forest management activities include maintaining and increasing forest extent, fostering forest resiliency and natural regeneration, encouraging sustainable harvest practices, balancing timber supply and wood utilization with tree growth, and preparing for future climate impacts. This study adds to a growing body of work that quantifies the relationships between forest growth, forest disturbance, and harvested wood product utilization, along with their collective influence on carbon stocks and fluxes, to identify pathways to enhance forest carbon sinks in support of state-level net-zero emission targets.
{"title":"Modeling climate-smart forest management and wood use for climate mitigation potential in Maryland and Pennsylvania","authors":"Chad C. Papa, Kendall DeLyser, Kylie Clay, Daphna Gadoth-Goodman, Lauren Cooper, Werner A. Kurz, Michael Magnan, Todd Ontl","doi":"10.3389/ffgc.2023.1259010","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1259010","url":null,"abstract":"State and local governments are increasingly interested in understanding the role forests and harvested wood products play in regional carbon sinks and storage, their potential contributions to state-level greenhouse gas (GHG) reductions, and the interactions between GHG reduction goals and potential economic opportunities. We used empirically driven process-based forest carbon dynamics and harvested wood product models in a systems-based approach to project the carbon impacts of various forest management and wood utilization activities in Maryland and Pennsylvania from 2007 to 2100. To quantify state-wide forest carbon dynamics, we integrated forest inventory data, harvest and management activity data, and remotely-sensed metrics of land-use change and natural forest disturbances within a participatory modeling approach. We accounted for net GHG emissions across (1) forest ecosystems (2) harvested wood products, (3) substitution benefits from wood product utilization, and (4) leakage associated with reduced in-state harvesting activities. Based on state agency partner input, a total of 15 management scenarios were modeled for Maryland and 13 for Pennsylvania, along with two climate change impact scenarios and two bioenergy scenarios for each state. Our findings show that both strategic forest management and wood utilization can provide substantial climate change mitigation potential relative to business-as-usual practices, increasing the forest C sink by 29% in Maryland and 38% in Pennsylvania by 2030 without disrupting timber supplies. Key climate-smart forest management activities include maintaining and increasing forest extent, fostering forest resiliency and natural regeneration, encouraging sustainable harvest practices, balancing timber supply and wood utilization with tree growth, and preparing for future climate impacts. This study adds to a growing body of work that quantifies the relationships between forest growth, forest disturbance, and harvested wood product utilization, along with their collective influence on carbon stocks and fluxes, to identify pathways to enhance forest carbon sinks in support of state-level net-zero emission targets.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135475677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-02DOI: 10.3389/ffgc.2023.1218134
Yuqian Wang, Geyan Liu, Mingyan Jiang, Qin Yang, Qibing Chen, Xi Li, Zhenghua Luo, Huixing Song, Juan Du, Xiaofang Yu, Bingyang Lv, Nian Li
Introduction As global urbanization intensifies, the physical and mental stressors of modern life have led to the growing prevalence of suboptimal health conditions. Spending time in a forest benefits human health and well-being. In this context, based on the forest spatial types (forest interior and forest edge spaces), landscape elements (architecture, water and roads) and forest stands (coniferous, broadleaf and bamboo forests), this study investigated the effects of different forest spatial landscape characteristics on the restorative potential for college students, aesthetic preference and eye movement behavior (total fixation duration and fixation count). Methods In this study, a total of 60 subjects were exposed to 42 photographs depicting typical forest landscapes acquired through field studies. The Short-version Revised Restoration and Preference Scale and eye-tracking technology, were employed to study the recovery efficiency and visual attraction of forest spatial of different forest spatial types, element compositions and forest stands. Results (1) The restorative potential and aesthetic preference score of forest edge spaces were significantly higher than those of forest interior spaces. (2) The restorative potential of bamboo forests was significantly higher than those of coniferous and broadleaf forests. (3) In terms of forest interior space, the restorative potential of “forest + 1 element” composition and “forest + 2 elements” composition was significantly higher than that of pure forest, and the restorative potential of interior space of bamboo forest was significantly higher than those of coniferous and broadleaf forests. (4) In terms of forest edge space, the restorative potential of “forest + 2 elements” composition was significantly higher than that of pure forest, and the restorative potential of pure forests was significantly higher than that of the “forest + 1 element” composition. (5) The restorative potential of forest spatial landscape characteristics positively correlated with aesthetic preference and negatively correlated with total fixation duration and fixation count. These results can provide a reference for future forest landscape research, construction and management.
{"title":"Effects of forest spatial types, element compositions and forest stands on restorative potential and aesthetic preference","authors":"Yuqian Wang, Geyan Liu, Mingyan Jiang, Qin Yang, Qibing Chen, Xi Li, Zhenghua Luo, Huixing Song, Juan Du, Xiaofang Yu, Bingyang Lv, Nian Li","doi":"10.3389/ffgc.2023.1218134","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1218134","url":null,"abstract":"Introduction As global urbanization intensifies, the physical and mental stressors of modern life have led to the growing prevalence of suboptimal health conditions. Spending time in a forest benefits human health and well-being. In this context, based on the forest spatial types (forest interior and forest edge spaces), landscape elements (architecture, water and roads) and forest stands (coniferous, broadleaf and bamboo forests), this study investigated the effects of different forest spatial landscape characteristics on the restorative potential for college students, aesthetic preference and eye movement behavior (total fixation duration and fixation count). Methods In this study, a total of 60 subjects were exposed to 42 photographs depicting typical forest landscapes acquired through field studies. The Short-version Revised Restoration and Preference Scale and eye-tracking technology, were employed to study the recovery efficiency and visual attraction of forest spatial of different forest spatial types, element compositions and forest stands. Results (1) The restorative potential and aesthetic preference score of forest edge spaces were significantly higher than those of forest interior spaces. (2) The restorative potential of bamboo forests was significantly higher than those of coniferous and broadleaf forests. (3) In terms of forest interior space, the restorative potential of “forest + 1 element” composition and “forest + 2 elements” composition was significantly higher than that of pure forest, and the restorative potential of interior space of bamboo forest was significantly higher than those of coniferous and broadleaf forests. (4) In terms of forest edge space, the restorative potential of “forest + 2 elements” composition was significantly higher than that of pure forest, and the restorative potential of pure forests was significantly higher than that of the “forest + 1 element” composition. (5) The restorative potential of forest spatial landscape characteristics positively correlated with aesthetic preference and negatively correlated with total fixation duration and fixation count. These results can provide a reference for future forest landscape research, construction and management.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"19 20","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135973209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-30DOI: 10.3389/ffgc.2023.1242878
Kenton L. Sena, Jerrica K. Flynn, Wendy Leuenberger, Randall Kolka, Christopher D. Barton
Introduction Timber harvests influence coarse woody debris (CWD) dynamics both initially and long-term—contributing a significant amount of CWD as slash immediately after harvest, but also removing some or all of the mature trees necessary to produce CWD over time. Whereas shelterwood and other similar timber harvest systems retain varying amounts of the overstory, preserving CWD production after harvest, commercial clearcutting essentially eliminates sources of fresh CWD until regenerating trees are large enough to contribute CWD through fallen limbs or trunks, often decades after harvest. Forestry best management practices (BMPs) are critical for reducing the water quality impacts of timber harvest, but their effects on riparian and stream CWD are not well understood. Methods The current project explores CWD dynamics (surveyed in 2001, 2004, 2009, and 2020) in three eastern Kentucky watersheds receiving differing timber harvest treatments in 1983: unharvested control, BMPs (clearcut with a protected streamside management zone), and no BMPs (clearcut). Results Analysis of hydrology data over the period of record demonstrated significant flooding in 2004 that likely “reset” CWD in the study watersheds. Coarse woody debris volume was higher in control (3.33 m 3 /ha) than no BMP (1.03 m 3 /ha) in 2020, with CWD accumulation rates ranging from 0.039 m 3 /ha in the no BMP watershed to 0.19 m 3 /ha in the control. Discussion While not significantly different, CWD volume was nominally higher in the BMP watershed than the No BMP watershed, suggesting that, in addition to their many other benefits, streamside management zones help facilitate CWD provisioning during stand initiation after a commercial clearcut harvest. Furthermore, this study suggests that provisioning of CWD may not recover after clearcut harvesting for 100 years or more.
木材采伐会影响初始和长期的粗木屑(CWD)动态,在采伐后立即产生大量的CWD,但随着时间的推移,也会去除产生CWD所需的部分或全部成熟树木。尽管防护林和其他类似的木材采伐系统保留了不同数量的被覆盖层,保留了采伐后产生的CWD,但商业性砍伐基本上消除了新CWD的来源,直到再生的树木足够大,通常在采伐后的几十年里,通过倒下的树枝或树干来贡献CWD。林业最佳管理实践(BMPs)对于减少木材采伐对水质的影响至关重要,但其对河岸和溪流CWD的影响尚未得到很好的了解。本项目探讨了肯塔基州东部三个流域的CWD动态(分别于2001年、2004年、2009年和2020年进行了调查),这些流域在1983年接受了不同的木材采伐处理:未采伐控制、bmp(有保护的河滨管理区的砍伐)和无bmp(砍伐)。结果有记录以来的水文数据分析表明,2004年发生了严重的洪水,可能“重置”了研究流域的CWD。2020年,对照区粗木屑体积(3.33 m 3 /ha)高于无BMP区(1.03 m 3 /ha), CWD累积速率从无BMP区0.039 m 3 /ha到对照区0.19 m 3 /ha不等。虽然没有显著差异,但BMP流域的CWD量名义上高于无BMP流域,这表明,除了它们的许多其他好处外,河滨管理区有助于在商业采伐后林分建立期间促进CWD的供应。此外,本研究表明,在采伐后100年或更长时间内,CWD的供应可能不会恢复。
{"title":"Long-term changes in coarse woody debris abundance in three Appalachian headwater streams with differing best management practices","authors":"Kenton L. Sena, Jerrica K. Flynn, Wendy Leuenberger, Randall Kolka, Christopher D. Barton","doi":"10.3389/ffgc.2023.1242878","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1242878","url":null,"abstract":"Introduction Timber harvests influence coarse woody debris (CWD) dynamics both initially and long-term—contributing a significant amount of CWD as slash immediately after harvest, but also removing some or all of the mature trees necessary to produce CWD over time. Whereas shelterwood and other similar timber harvest systems retain varying amounts of the overstory, preserving CWD production after harvest, commercial clearcutting essentially eliminates sources of fresh CWD until regenerating trees are large enough to contribute CWD through fallen limbs or trunks, often decades after harvest. Forestry best management practices (BMPs) are critical for reducing the water quality impacts of timber harvest, but their effects on riparian and stream CWD are not well understood. Methods The current project explores CWD dynamics (surveyed in 2001, 2004, 2009, and 2020) in three eastern Kentucky watersheds receiving differing timber harvest treatments in 1983: unharvested control, BMPs (clearcut with a protected streamside management zone), and no BMPs (clearcut). Results Analysis of hydrology data over the period of record demonstrated significant flooding in 2004 that likely “reset” CWD in the study watersheds. Coarse woody debris volume was higher in control (3.33 m 3 /ha) than no BMP (1.03 m 3 /ha) in 2020, with CWD accumulation rates ranging from 0.039 m 3 /ha in the no BMP watershed to 0.19 m 3 /ha in the control. Discussion While not significantly different, CWD volume was nominally higher in the BMP watershed than the No BMP watershed, suggesting that, in addition to their many other benefits, streamside management zones help facilitate CWD provisioning during stand initiation after a commercial clearcut harvest. Furthermore, this study suggests that provisioning of CWD may not recover after clearcut harvesting for 100 years or more.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"180 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136068621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-27DOI: 10.3389/ffgc.2023.1303886
José Carlos Miranda, Unai López de Heredia, Victoria Fernández, Pilar Pita
Global change is affecting the frequency and temporal distribution of frost events. We can expect damage caused by low temperatures to increase specially at the upper limit of a species’ elevation range. Here, we assessed how Pinus canariensis two-year old seedlings from different islands and elevations responded differently to chilling and freezing temperatures. Seedlings from six populations were grown either in a greenhouse (t min = 5 ̊C, chilling conditions) or outdoors (t min = −3.3 ̊C, freezing conditions) for 104 days in winter. Seedlings from one of these populations belonged to three half-sib families. Maximum quantum yield of Photosystem II and evapotranspiration (ETP) were determined four times throughout the study. All populations suffered photoinhibition under freezing but not under chilling conditions. We measured the lowest ETP in the population from the warmest and driest environment and lowest elevation (250 m) both under chilling and freezing conditions. The three populations from the higher elevations reached the highest ETP under chilling, a likely adaptation to the shortening of the vegetative period. The effect of elevation remained elusive for other parameters, which could be partly attributed to high intrapopulation variability. Epicuticular wax concentration increased and needle water content decreased in plants growing outdoors. All populations except the one most affected by cold dehydration showed osmotic adjustment and a simultaneous decrease in tissue elasticity under freezing. This response was stronger in the population from the highest elevation (2,241 m). Our results highlight the coexistence of adaptive processes, genetic variation and plasticity conditioning the response to low temperatures in this species.
{"title":"Phenotypic plasticity in Pinus canariensis seedlings growing at chilling and freezing temperatures","authors":"José Carlos Miranda, Unai López de Heredia, Victoria Fernández, Pilar Pita","doi":"10.3389/ffgc.2023.1303886","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1303886","url":null,"abstract":"Global change is affecting the frequency and temporal distribution of frost events. We can expect damage caused by low temperatures to increase specially at the upper limit of a species’ elevation range. Here, we assessed how Pinus canariensis two-year old seedlings from different islands and elevations responded differently to chilling and freezing temperatures. Seedlings from six populations were grown either in a greenhouse (t min = 5 ̊C, chilling conditions) or outdoors (t min = −3.3 ̊C, freezing conditions) for 104 days in winter. Seedlings from one of these populations belonged to three half-sib families. Maximum quantum yield of Photosystem II and evapotranspiration (ETP) were determined four times throughout the study. All populations suffered photoinhibition under freezing but not under chilling conditions. We measured the lowest ETP in the population from the warmest and driest environment and lowest elevation (250 m) both under chilling and freezing conditions. The three populations from the higher elevations reached the highest ETP under chilling, a likely adaptation to the shortening of the vegetative period. The effect of elevation remained elusive for other parameters, which could be partly attributed to high intrapopulation variability. Epicuticular wax concentration increased and needle water content decreased in plants growing outdoors. All populations except the one most affected by cold dehydration showed osmotic adjustment and a simultaneous decrease in tissue elasticity under freezing. This response was stronger in the population from the highest elevation (2,241 m). Our results highlight the coexistence of adaptive processes, genetic variation and plasticity conditioning the response to low temperatures in this species.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136312365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"RE:Growth—A toolkit for analyzing secondary forest aboveground carbon dynamics in the Brazilian Amazon","authors":"Viola H. A. Heinrich, Stephen Sitch, Thais M. Rosan, Celso H. L. Silva-Junior, Luiz E. O. C. Aragão","doi":"10.3389/ffgc.2023.1230734","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1230734","url":null,"abstract":"DATA REPORT article Front. For. Glob. Change, 27 October 2023Sec. Tropical Forests Volume 6 - 2023 | https://doi.org/10.3389/ffgc.2023.1230734","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"37 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136311482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-27DOI: 10.3389/ffgc.2023.1240804
Shulin He, Amrita Chakraborty, Fei Li, Cao Zhou, Binchuan Zhang, Bin Chen, Bin Jiang
Termites play an important role as decomposers of organic matter in forests by utilizing their gut symbionts and associated carbohydrate-active enzymes (CAZymes) to digest wood materials. However, there is a limited understanding of the entire repertoire of CAZymes and their evolution in termite genomes. Here we identified the gene families of CAZymes in publicly available termite genomes and analyzed the evolution of abundant gene families. We found that 79 CAZyme gene families from the carbohydrate-binding module and four CAZyme classes, including glycosyl transferase (GT), glycoside hydrolase (GH), auxiliary activity (AA) and carbohydrate esterase (CE), were present in termites with minor variations across termite species except for a few gene families. The gene trees of the large and conserved gene families have several groups of genes from all species, and each group encodes enzymes with complete corresponding domains. Three gene families, namely GT1, GH1 and AA3, exhibited significant variations in gene numbers and experienced several losses and a few duplications, which might be related to their rich gut symbionts and newly gained functions. Furthermore, the overall expression of CAZymes appears to have a caste- and tissue-specific pattern, reflecting a division of labor in termite colonies. Overall, these results reveal a likely stable CAZyme repertoire in termites and pave the way for further research on the functional contribution of termites to wood digestion.
{"title":"Genome-wide identification reveals conserved carbohydrate-active enzyme repertoire in termites","authors":"Shulin He, Amrita Chakraborty, Fei Li, Cao Zhou, Binchuan Zhang, Bin Chen, Bin Jiang","doi":"10.3389/ffgc.2023.1240804","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1240804","url":null,"abstract":"Termites play an important role as decomposers of organic matter in forests by utilizing their gut symbionts and associated carbohydrate-active enzymes (CAZymes) to digest wood materials. However, there is a limited understanding of the entire repertoire of CAZymes and their evolution in termite genomes. Here we identified the gene families of CAZymes in publicly available termite genomes and analyzed the evolution of abundant gene families. We found that 79 CAZyme gene families from the carbohydrate-binding module and four CAZyme classes, including glycosyl transferase (GT), glycoside hydrolase (GH), auxiliary activity (AA) and carbohydrate esterase (CE), were present in termites with minor variations across termite species except for a few gene families. The gene trees of the large and conserved gene families have several groups of genes from all species, and each group encodes enzymes with complete corresponding domains. Three gene families, namely GT1, GH1 and AA3, exhibited significant variations in gene numbers and experienced several losses and a few duplications, which might be related to their rich gut symbionts and newly gained functions. Furthermore, the overall expression of CAZymes appears to have a caste- and tissue-specific pattern, reflecting a division of labor in termite colonies. Overall, these results reveal a likely stable CAZyme repertoire in termites and pave the way for further research on the functional contribution of termites to wood digestion.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"54 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136234545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tree mortality is a complex process that not only be affected by the various factors, such as stand and climate factors, but also the various long-term effects of the factors to each other. In this study, based on the long-term spacing trials of Chinese fir in four regions of southern China, a Bayesian network was used to model tree mortality in response to stand and climate factors, as well as comparing this approach with logistic regression and random forest method. The results showed that the Bayesian network method had the highest accuracy in predicting tree mortality. In addition, the Bayesian network approach could find the dependency in the relationship between data and provide a theoretical framework for modeling uncertainty by using probabilistic calculus and underlying graph structure. Sensitivity analysis showed relative diameter was the most important factor, and temperature was the most important climate factor. Furthermore, climate factors not only directly affected tree mortality, but also indirectly affected tree mortality through affecting relative diameter, stand density and Gini coefficient. We also found that stand competition, structural heterogeneity and age affected tree mortality under climate change, and a moderate level of competition condition and stand structure heterogeneity weakened the negative impact of climate factors on tree mortality. Old trees were more sensitive to climate change than young trees, especially under extreme climate conditions. Besides, we found that tree mortality was negatively correlated with moderate annual precipitation, winter mean minimum temperature, and stand structure (Gini), and low age, but positively correlated with low relative diameter, high density and age. The results will provide adaptive options for effective forest management of Chinese fir plantations under the backdrop of global climate change in the future.
{"title":"A Bayesian network model to disentangle the effects of stand and climate factors on tree mortality of Chinese fir plantations","authors":"Yihang Jiang, Zhen Wang, Hanyue Chen, Yuxin Hu, Yancheng Qu, Sophan Chhin, Jianguo Zhang, Xiongqing Zhang","doi":"10.3389/ffgc.2023.1298968","DOIUrl":"https://doi.org/10.3389/ffgc.2023.1298968","url":null,"abstract":"Tree mortality is a complex process that not only be affected by the various factors, such as stand and climate factors, but also the various long-term effects of the factors to each other. In this study, based on the long-term spacing trials of Chinese fir in four regions of southern China, a Bayesian network was used to model tree mortality in response to stand and climate factors, as well as comparing this approach with logistic regression and random forest method. The results showed that the Bayesian network method had the highest accuracy in predicting tree mortality. In addition, the Bayesian network approach could find the dependency in the relationship between data and provide a theoretical framework for modeling uncertainty by using probabilistic calculus and underlying graph structure. Sensitivity analysis showed relative diameter was the most important factor, and temperature was the most important climate factor. Furthermore, climate factors not only directly affected tree mortality, but also indirectly affected tree mortality through affecting relative diameter, stand density and Gini coefficient. We also found that stand competition, structural heterogeneity and age affected tree mortality under climate change, and a moderate level of competition condition and stand structure heterogeneity weakened the negative impact of climate factors on tree mortality. Old trees were more sensitive to climate change than young trees, especially under extreme climate conditions. Besides, we found that tree mortality was negatively correlated with moderate annual precipitation, winter mean minimum temperature, and stand structure (Gini), and low age, but positively correlated with low relative diameter, high density and age. The results will provide adaptive options for effective forest management of Chinese fir plantations under the backdrop of global climate change in the future.","PeriodicalId":12538,"journal":{"name":"Frontiers in Forests and Global Change","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135113005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}