Forest Ecosystems最新文献

{"title":"Disparities in tree mortality among plant functional types (PFTs) in a temperate forest: Insights into size-dependent and PFT-specific patterns","authors":"Man Hu ,&nbsp;Hang Shi ,&nbsp;Rui He ,&nbsp;Bingbin Wen ,&nbsp;Haikun Liu ,&nbsp;Kerong Zhang ,&nbsp;Xiao Shu ,&nbsp;Haishan Dang ,&nbsp;Quanfa Zhang","doi":"10.1016/j.fecs.2024.100208","DOIUrl":"https://doi.org/10.1016/j.fecs.2024.100208","url":null,"abstract":"<div><p>Tree mortality significantly influences forest structure and function, yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types (PFTs) remains incomplete. This study analysed size-dependent tree mortality in a temperate forest, encompassing 46 tree species and 32,565 individuals across different PFTs (i.e., evergreen conifer vs. deciduous broadleaf species, shade-tolerant vs. shade-intolerant species). By employing all-subset regression procedures and logistic generalized linear mixed-effects models, we identified distinct mortality patterns influenced by biotic and abiotic factors. Our results showed a stable mortality pattern in evergreen conifer species, contrasted by a declining pattern in deciduous broadleaf and shade-tolerant, as well as shade-intolerant species, across size classes. The contribution to tree mortality of evergreen conifer species shifted from abiotic to biotic factors with increasing size, while the mortality of deciduous broadleaf species was mainly influenced by biotic factors, such as initial diameter at breast height (DBH) and conspecific negative density. For shade-tolerant species, the mortality of small individuals was mainly determined by initial DBH and conspecific negative density dependence, whereas the mortality of large individuals was subjected to the combined effect of biotic (competition from neighbours) and abiotic factors (i.e., convexity and pH). As for shade-intolerant species, competition from neighbours was found to be the main driver of tree mortality throughout their growth stages. Thus, these insights enhance our understanding of forest dynamics by revealing the size-dependent and PFT-specific tree mortality patterns, which may inform strategies for maintaining forest diversity and resilience in temperate forest ecosystems.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100208"},"PeriodicalIF":4.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000447/pdfft?md5=67b49fa6a809516f2ff805b84975cf5c&pid=1-s2.0-S2197562024000447-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141328828","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}

{"title":"Root overlap and allocation of above- and belowground growth of European beech in pure and mixed stands of Douglas fir and Norway spruce","authors":"Amani S. Lwila ,&nbsp;Christian Ammer ,&nbsp;Oliver Gailing ,&nbsp;Ludger Leinemann ,&nbsp;Martina Mund","doi":"10.1016/j.fecs.2024.100217","DOIUrl":"10.1016/j.fecs.2024.100217","url":null,"abstract":"<div><p>Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed stands. However, mechanisms that may contribute to this effect are rarely studied, even though they are essential to assess the potential of species to cope with climate change. This study examined fine root overlap and the linkage between fine root and stem growth of European beech (<em>Fagus sylvatica</em>) growing in pure and mixed stands with Douglas fir (<em>Pseudotsuga menziesii</em>) or Norway spruce (<em>Picea abies</em>) at two different study sites in northwestern Germany.</p><p>The study sites represented substantially different soil and climate conditions. At each site, three stands, and at each stand, three pairs of trees were studied. In the pure beech stand, the pairs consisted of two beech trees, while in the mixed stands each pair was composed of a beech tree and a conifer. Between each pair, three evenly spaced soil cores were taken monthly throughout the growing season. In the pure beech stands, microsatellite markers were used to assign the fine roots to individual trees. Changes in stem diameter of beech were quantified and then upscaled to aboveground wood productivity with automatic high-resolution circumference dendrometers.</p><p>We found that fine root overlap between neighboring trees varied independently of the distance between the paired trees or the stand types (pure versus mixed stands), indicating that there was no territorial competition. Aboveground wood productivity (wood NPP) and fine root productivity (root NPP) showed similar unimodal seasonal patterns, peaking in June. However, this pattern was more distinct for root NPP, and root NPP started earlier and lasted longer than wood NPP. The influence of site conditions on the variation in wood and root NPP of beech was stronger than that of stand type. Wood NPP was, as expected, higher at the richer site than at the poorer site. In contrast, root NPP was higher at the poorer than at the richer site.</p><p>We concluded that beech can respond to limited resources not only above- but also belowground and that the negative relationship between above- and belowground growth across the study sites suggests an ‘optimal partitioning’ of growth under stress.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100217"},"PeriodicalIF":3.8,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000538/pdfft?md5=76c987e312ae18c3d30bae356d235762&pid=1-s2.0-S2197562024000538-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783505","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}

{"title":"Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate","authors":"Zhengchao Ren ,&nbsp;Lei Liu ,&nbsp;Fang Yin ,&nbsp;Xiaoni Liu","doi":"10.1016/j.fecs.2024.100180","DOIUrl":"https://doi.org/10.1016/j.fecs.2024.100180","url":null,"abstract":"<div><p>Potential natural vegetation (PNV) is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide. However, there is limited knowledge on the spatio-temporal distributions, transitional processes, and underlying mechanisms of global natural vegetation, particularly in the case of ongoing climate warming. In this study, we visualize the spatio-temporal pattern and inter-transition procedure of global PNV, analyse the shifting distances and directions of global PNV under the influence of climatic disturbance, and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations. To achieve this, we utilize meteorological data, mainly temperature and precipitation, from six phases: the Last Inter-Glacial (LIG), the Last Glacial Maximum (LGM), the Mid Holocene (MH), the Present Day (PD), 2030 (2021–2040) and 2090 (2081–2100), and employ a widely-accepted comprehensive and sequential classification system (CSCS) for global PNV classification. We find that the spatial patterns of five PNV groups (forest, shrubland, savanna, grassland and tundra) generally align with their respective ecotopes, although their distributions have shifted due to fluctuating temperature and precipitation. Notably, we observe an unexpected transition between tundra and savanna despite their geographical distance. The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation, although there is heterogeneity among these shifts for each group. Indeed, the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate. The spatio-temporal distributions, mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate, as revealed in this study, can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100180"},"PeriodicalIF":4.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000162/pdfft?md5=410f3a31692ea764100dcf8a5cdcbb8d&pid=1-s2.0-S2197562024000162-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140162591","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}

{"title":"The changes in soil organic carbon stock and quality across a subalpine forest successional series","authors":"Fei Li ,&nbsp;Zhihui Wang ,&nbsp;Jianfeng Hou ,&nbsp;Xuqing Li ,&nbsp;Dan Wang ,&nbsp;Wanqin Yang","doi":"10.1016/j.fecs.2024.100203","DOIUrl":"10.1016/j.fecs.2024.100203","url":null,"abstract":"<div><p>Soil organic carbon (SOC) affects the function of terrestrial ecosystem and plays a vital role in global carbon cycle. Yet, large uncertainty still existed regarding the changes in SOC stock and quality with forest succession. Here, the stock and quality of SOC at 1-m soil profile were investigated across a subalpine forest series, including shrub, deciduous broad-leaved forest, broadleaf-conifer mixed forest, middle-age coniferous forest and mature coniferous forest, which located at southeast of Tibetan Plateau. The results showed that SOC stock ranged from 9.8 to 29.9 ​kg⋅m⁻², and exhibited a hump-shaped response pattern across the forest successional series. The highest and lowest SOC stock was observed in the mixed forest and shrub forest, respectively. The SOC stock had no significant relationships with soil temperature and litter stock, but was positively correlated with wood debris stock. Meanwhile, the average percentages of polysaccharides, lignins, aromatics and aliphatics based on FTIR spectroscopy were 79.89%, 0.94%, 18.87% and 0.29%, respectively. Furthermore, the percentage of polysaccharides exhibited an increasing pattern across the forest successional series except for the sudden decreasing in the mixed forest, while the proportions of lignins, aromatics and aliphatics exhibited a decreasing pattern across the forest successional series except for the sudden increasing in the mixed forest. Consequently, the humification indices (HIs) were highest in the mixed forest compared to the other four successional stages, which means that the SOC quality in mixed forest was worse than other successional stages. In addition, the SOC stock, recalcitrant fractions and HIs decreased with increasing soil depth, while the polysaccharides exhibited an increasing pattern. These findings demonstrate that the mixed forest had higher SOC stock and worse SOC quality than other successional stages. The high proportion of SOC stock (66% at depth of 20–100 ​cm) and better SOC quality (lower HIs) indicate that deep soil have tremendous potential to store SOC and needs more attention under global change.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100203"},"PeriodicalIF":4.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000393/pdfft?md5=e6db9bfe67ed06f5a320a1ebd874d915&pid=1-s2.0-S2197562024000393-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141044420","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}

{"title":"Tree mycorrhizal associations determine how biodiversity, large trees, and environmental factors drive aboveground carbon stock in temperate forests","authors":"Yue Chen ,&nbsp;Zikun Mao ,&nbsp;Jonathan A. Myers ,&nbsp;Jinghua Yu ,&nbsp;Xugao Wang","doi":"10.1016/j.fecs.2024.100205","DOIUrl":"10.1016/j.fecs.2024.100205","url":null,"abstract":"<div><p>Biodiversity, large trees, and environmental conditions such as climate and soil have important effects on forest carbon stocks. However, recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations, whereby large-tree effects may be driven by ectomycorrhizal (EM) trees, diversity effects may be driven by arbuscular mycorrhizal (AM) trees, and environment effects may depend on differential climate and soil preferences of AM and EM trees. To test this hypothesis, we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots (30 m ​× ​30 ​m) across Northeast China to examine how biodiversity (species diversity and ecological uniqueness), large trees (top 1% of tree diameters), and environmental factors (climate and soil nutrients) differently regulate aboveground carbon stocks of AM trees, EM trees, and AM and EM trees combined (i.e. total aboveground carbon stock). We found that large trees had a positive effect on both AM and EM tree carbon stocks. However, biodiversity and environmental factors had opposite effects on AM vs. EM tree carbon stocks. Specifically, the two components of biodiversity had positive effects on AM tree carbon stocks, but negative effects on EM tree carbon stocks. Environmental heterogeneity (mean annual temperature and soil nutrients) also exhibited contrasting effects on AM and EM tree carbon stocks. Consequently, for the total carbon stock, the positive large-tree effect far surpasses the diversity and environment effect. This is mainly because when integrating AM and EM tree carbon stock into total carbon stock, the opposite diversity-effect (also environment-effect) on AM vs. EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified. In summary, this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100205"},"PeriodicalIF":4.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000411/pdfft?md5=349f3edcad5d7d48f4496576cadd177c&pid=1-s2.0-S2197562024000411-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141048048","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}

{"title":"Evolution history dominantly regulates fine root lifespan in tree species across the world","authors":"Xingzhao Huang ,&nbsp;Zhouying Lu ,&nbsp;Fangbing Li ,&nbsp;Yang Deng ,&nbsp;Fangfang Wan ,&nbsp;Quancheng Wang ,&nbsp;Fousseni Folega ,&nbsp;Jinsong Wang ,&nbsp;Zijian Guo","doi":"10.1016/j.fecs.2024.100211","DOIUrl":"10.1016/j.fecs.2024.100211","url":null,"abstract":"<div><p>Understanding the drivers of variations in fine root lifespan is key to informing nutrient cycling and productivity in terrestrial ecosystems. However, the general patterns and determinants of forest fine root lifespan at the global scale are still limited. We compiled a dataset of 421 fine root lifespan observations from 76 tree species globally to assess phylogenetic signals among species, explored relationships between fine root lifespan and biotic and abiotic factors, and quantified the relative importance of phylogeny, root system structure and functions, climatic and edaphic factors in driving global fine root lifespan variations. Overall, fine root lifespan showed a clear phylogenetic signal, with gymnosperms having a longer fine root lifespan than angiosperms. Fine root lifespan was longer for evergreens than deciduous trees. Ectomycorrhizal (ECM) plants had an extended fine root lifespan than arbuscular mycorrhizal (AM) plants. Among different climatic zones, fine root lifespan was the longest in the boreal zone, while it did not vary between the temperate and tropical zone. Fine root lifespan increased with soil depth and root order. Furthermore, the analysis of relative importance indicated that phylogeny was the strongest driver influencing the variation in forest fine root lifespan, followed by soil clay content, root order, mean annual temperature, and soil depth, while other environmental factors and root traits exerted weaker effects. Our results suggest that the global pattern of fine root lifespan in forests is shaped by the interplay of phylogeny, root traits and environmental factors. These findings necessitate accurate representations of tree evolutionary history in earth system models to predict fine root longevity and its responses to global changes.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100211"},"PeriodicalIF":4.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000472/pdfft?md5=5447aa628756eb0d851064c871ad9c7d&pid=1-s2.0-S2197562024000472-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141280586","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}

{"title":"Aboveground carbon sequestration of Cunninghamia lanceolata forests: Magnitude and drivers","authors":"Chen Wang ,&nbsp;Shuguang Liu ,&nbsp;Yu Zhu ,&nbsp;Andrew R. Smith ,&nbsp;Ying Ning ,&nbsp;Deming Deng","doi":"10.1016/j.fecs.2024.100165","DOIUrl":"10.1016/j.fecs.2024.100165","url":null,"abstract":"<div><p>Understanding the spatial variation, temporal changes, and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management options. How carbon density and sequestration in various <em>Cunninghamia lanceolata</em> forests, extensively cultivated for timber production in subtropical China, vary with biodiversity, forest structure, environment, and cultural factors remain poorly explored, presenting a critical knowledge gap for realizing carbon sequestration supply potential through management. Based on a large-scale database of 449 permanent forest inventory plots, we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in <em>Cunninghamia lanceolate</em> forests in Hunan Province, China, and attributed the contributions of stand structure, environmental, and management factors to the heterogeneity using quantile age-sequence analysis, partial least squares path modeling (PLS-PM), and hot-spot analysis. The results showed lower values of carbon density and sequestration on average, in comparison with other forests in the same climate zone (i.e., subtropics), with pronounced spatial and temporal variability. Specifically, quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests (0.50 and 1.80 ​Mg⋅​ha⁻¹·yr⁻¹). PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature forests. Furthermore, species diversity and geo-topographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low- and high-carbon-bearing forests. Hotspot analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon sequestration. Our work highlighted that retaining large-sized DBH trees and increasing shade-tolerant tree species were important to enhance carbon sequestration in <em>C. lanceolate</em> forests.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100165"},"PeriodicalIF":4.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000010/pdfft?md5=8270a5a0778c4584386a23958c406575&pid=1-s2.0-S2197562024000010-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139394029","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}

{"title":"Differential modulation of crown allometry and stem growth at gap edges in five European tree species by drought conditions","authors":"Luke Bohnhorst ,&nbsp;Peter Biber ,&nbsp;Torben Hilmers ,&nbsp;Enno Uhl ,&nbsp;Hans Pretzsch","doi":"10.1016/j.fecs.2024.100219","DOIUrl":"10.1016/j.fecs.2024.100219","url":null,"abstract":"<div><h3>Background</h3><p>In Central Europe, forests are increasingly affected by various disturbances, resulting in an increasing gap formation in the canopy. In order to support goal-oriented management, more knowledge is required about the acclimation of the crown and its effects on the basal area growth of trees at the edge of a gap.</p></div><div><h3>Methods</h3><p>This work compared trees' growth and crown structure at the edge of a transient gap, with a gap size of more than 80 ​m², with trees in the stand that were at least 30 ​m away from the gap. A total of 249 European beeches (<em>Fagus sylvatica</em> L.), Norway spruces (<em>Picea abies</em> L. Karst), Scots pines (<em>Pinus sylvestris</em> L.), oaks (<em>Quercus</em> spp.; <em>Quercus petraea</em> (Matt.) Liebl., <em>Quercus robur</em> L.), and silver firs (<em>Abies alba</em> Mill.) were examined on long-term experimental plots in southern Germany. Various crown measures were developed and calculated using high-resolution terrestrial laser scanning (TLiDAR) to capture the three-dimensional crown structures. Growth responses to edge conditions were measured based on tree rings. Using linear mixed models, we predict the basal area increment of edge trees relative to trees in the stand under wet and dry soil moisture conditions after the gap formation.</p></div><div><h3>Results</h3><p>We identified i) species-specific acclimation of the crown of edge trees after the gap formation, ii) under wet soil moisture conditions a growth increase of 25%–45% for beech, pine, and oak edge trees and growth losses of 5%–60% for spruce and fir and iii) coniferous tree species benefited from the edge position regarding their basal area increment under dry soil moisture conditions and deciduous tree species grew regardless of the soil moisture conditions at the edge of a gap.</p></div><div><h3>Conclusion</h3><p>Gaps have a species-specific effect on the habitus and growth of edge trees and can have both positive and negative impacts on silviculture.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100219"},"PeriodicalIF":3.8,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000551/pdfft?md5=9698aac09aedca623bcd0a67a6883f93&pid=1-s2.0-S2197562024000551-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141568008","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}

{"title":"Divergent changes in diversity and network complexity across different trophic-level organisms drive soil multifunctionality of fire-impacted subtropical forests","authors":"Luhong Zhou ,&nbsp;Shangshi Liu ,&nbsp;Debao Lin ,&nbsp;Hang-Wei Hu ,&nbsp;Ji-Zheng He","doi":"10.1016/j.fecs.2024.100227","DOIUrl":"10.1016/j.fecs.2024.100227","url":null,"abstract":"<div><p>Widespread forest fires pose significant challenges to the diverse communities of soil-dwelling organisms and the multiple ecosystem functions they support. However, whether the biodiversity and interactions of various taxonomic groups respond to fire consistently in terms of direction and extent, and their relative role in regulating post-fire soil functioning, remains largely unexplored. In this study, we investigated whether the diversity and co-occurrence networks of soil organisms across various trophic levels (including bacteria, fungi, protists, and invertebrates) in subtropical forests exhibit consistent responses to fire. Furthermore, we investigated their contribution to regulating soil multifunctionality, which is measured by a range of soil extracellular enzyme activities, available nutrients and reduced potential fungal plant pathogens. Our findings revealed that fire led to a decline in the richness of fungi, protists, and invertebrates, without significantly impacting bacterial richness. Fire also simplified the microbial co-occurrence networks while complexifying the invertebrate networks. Interestingly, soil multifunctionality tended to decrease with the richness of lower-trophic communities (i.e., bacteria), whereas it increased with that of high-trophic communities (i.e., protists and invertebrates). Moreover, fire indirectly influenced soil multifunctionality by altering biodiversity and network complexity, particularly pronounced in high-trophic communities. Overall, our results underscored the divergent vulnerability of biodiversity and networks to fires across taxa groups, highlighting the crucial role of biodiversity and interactions of higher trophic taxa groups in shaping the recovery and functionality of fire-affected soils.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100227"},"PeriodicalIF":3.8,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000630/pdfft?md5=2f9ac01f19e62306efd08b294ec40e73&pid=1-s2.0-S2197562024000630-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783502","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}

{"title":"Individual tree segmentation in occluded complex forest stands through ellipsoid directional searching and point compensation","authors":"Qingjun Zhang,&nbsp;Shangshu Cai,&nbsp;Xinlian Liang","doi":"10.1016/j.fecs.2024.100238","DOIUrl":"10.1016/j.fecs.2024.100238","url":null,"abstract":"<div><p>Terrestrial laser scanning (TLS) accurately captures tree structural information and provides prerequisites for tree-scale estimations of forest biophysical attributes. Quantifying tree-scale attributes from TLS point clouds requires segmentation, yet the occlusion effects severely affect the accuracy of automated individual tree segmentation. In this study, we proposed a novel method using ellipsoid directional searching and point compensation algorithms to alleviate occlusion effects. Firstly, region growing and point compensation algorithms are used to determine the location of tree roots. Secondly, the neighbor points are extracted within an ellipsoid neighborhood to mitigate occlusion effects compared with <em>k</em>-nearest neighbor (KNN). Thirdly, neighbor points are uniformly subsampled by the directional searching algorithm based on the Fibonacci principle in multiple spatial directions to reduce memory consumption. Finally, a graph describing connectivity between a point and its neighbors is constructed, and it is utilized to complete individual tree segmentation based on the shortest path algorithm. The proposed method was evaluated on a public TLS dataset comprising six forest plots with three complexity categories in Evo, Finland, and it reached the highest mean accuracy of 77.5%, higher than previous studies on tree detection. We also extracted and validated the tree structure attributes using manual segmentation reference values. The RMSE, RMSE%, bias, and bias% of tree height, crown base height, crown projection area, crown surface area, and crown volume were used to evaluate the segmentation accuracy, respectively. Overall, the proposed method avoids many inherent limitations of current methods and can accurately map canopy structures in occluded complex forest stands.</p></div>","PeriodicalId":54270,"journal":{"name":"Forest Ecosystems","volume":"11 ","pages":"Article 100238"},"PeriodicalIF":3.8,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2197562024000745/pdfft?md5=db280e51021c5d65527901abe100b8a2&pid=1-s2.0-S2197562024000745-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142121654","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}