Pub Date : 2024-09-01DOI: 10.1093/forestry/cpae044
Gergő Diószegi, Vanda Éva Molnár, Loránd Attila Nagy, Péter Enyedi, Péter Török, Szilárd Szabó
Accurate information regarding tree canopy characteristics is crucial for forest management, but it is often difficult to assess. This study presents an innovative framework designed for crown base height (CBH) detection using high-resolution laser-scanned data, with a specific focus on individual trees within forests. The framework comprises three key steps: (i) segmenting the input tree point cloud to identify the tree trunk and its branches using the treesio software; (ii) applying vertical cross-sectional K-means clustering to cluster the identified tree and to define the elevation threshold for removing low-lying understory vegetation; (iii) employing a novel 2D kernel method for detecting CBH after eliminating low-lying understory vegetation. The 2D kernel method, developed for broadleaf forests using leaf-off airborne laser scanning (ALS) data, underpins the treecbh tool. This tool features a visual CBH adjustment component that shows a 2D profile plot of the tree point cloud, and suggests a CBH value for user approval or adjustment. To evaluate accuracy, in situ measured CBH data from five forest plots in Germany and Hungary with varied species compositions were used. ALS data were collected during leaf-off conditions for the two Hungarian plots and during leaf-on conditions for the three German plots. Leaf-off terrestrial laser-scanned data from individual trees were also used in the accuracy assessment. A sensitivity analysis using random point decimation was conducted on the terrestrial laser-scanned data to assess treecbh’s sensitivity to point density. The initial results exhibited matching rates of 45% and 60% for leaf-off ALS plots, which significantly improved to 71% and 77%, respectively, when using the visual CBH adjustment feature of the tool. The leaf-on ALS results demonstrated matching rates between 24% and 33%, whereas the CBHs of individual terrestrial laser-scanned trees could be detected with 93% accuracy in visual mode. It was observed that treecbh operates effectively when the input ALS data have a minimum point density of 20 pts/${text{m}}^2$, with its optimal performance achieved at 110 pts/${text{m}}^2$. These findings indicated treecbh’s sensitivity to ALS data quality, scanning season (leaf-on and leaf-off), and point density. This sensitivity can be effectively mitigated in the case of leaf-off ALS data by utilizing the visual CBH adjustment feature of the tool.
有关树冠特征的准确信息对森林管理至关重要,但往往难以评估。本研究提出了一个创新框架,旨在利用高分辨率激光扫描数据进行树冠基高(CBH)检测,重点是森林中的单棵树木。该框架包括三个关键步骤(i) 使用 treesio 软件对输入的树木点云进行分割,以识别树干及其分支;(ii) 应用垂直截面 K-means 聚类对识别出的树木进行聚类,并确定去除低洼林下植被的海拔阈值;(iii) 在去除低洼林下植被后,采用新型二维核方法检测 CBH。二维核方法是利用离叶机载激光扫描(ALS)数据为阔叶林开发的,是 treecbh 工具的基础。该工具具有可视化 CBH 调整组件,可显示树木点云的二维剖面图,并提出 CBH 值供用户批准或调整。为了评估准确性,我们使用了德国和匈牙利五块林地的原位测量 CBH 数据,这些林地的树种组成各不相同。两块匈牙利地块的 ALS 数据是在落叶期采集的,三块德国地块的 ALS 数据是在开叶期采集的。在精度评估中还使用了单棵树木的落叶地面激光扫描数据。为了评估 treecbh 对点密度的敏感性,我们对地面激光扫描数据进行了随机点去角质敏感性分析。初步结果显示,离叶 ALS 地块的匹配率分别为 45% 和 60%,而使用该工具的可视化 CBH 调整功能后,匹配率分别大幅提高到 71% 和 77%。叶上 ALS 结果显示的匹配率介于 24% 和 33% 之间,而在视觉模式下,单个地面激光扫描树木的 CBH 检测准确率为 93%。据观察,当输入的 ALS 数据的最小点密度为 20 点/${text{m}}^2$ 时,treecbh 可有效运行,而当输入的 ALS 数据的最小点密度为 110 点/${text{m}}^2$ 时,treecbh 可达到最佳性能。这些发现表明,treecbh 对 ALS 数据质量、扫描季节(落叶期和落叶期)以及点密度非常敏感。通过利用该工具的可视化 CBH 调整功能,可以有效地减轻对落叶 ALS 数据的敏感性。
{"title":"Testing treecbh in Central European forests: an R package for crown base height detection using high-resolution aerial laser-scanned data","authors":"Gergő Diószegi, Vanda Éva Molnár, Loránd Attila Nagy, Péter Enyedi, Péter Török, Szilárd Szabó","doi":"10.1093/forestry/cpae044","DOIUrl":"https://doi.org/10.1093/forestry/cpae044","url":null,"abstract":"Accurate information regarding tree canopy characteristics is crucial for forest management, but it is often difficult to assess. This study presents an innovative framework designed for crown base height (CBH) detection using high-resolution laser-scanned data, with a specific focus on individual trees within forests. The framework comprises three key steps: (i) segmenting the input tree point cloud to identify the tree trunk and its branches using the treesio software; (ii) applying vertical cross-sectional K-means clustering to cluster the identified tree and to define the elevation threshold for removing low-lying understory vegetation; (iii) employing a novel 2D kernel method for detecting CBH after eliminating low-lying understory vegetation. The 2D kernel method, developed for broadleaf forests using leaf-off airborne laser scanning (ALS) data, underpins the treecbh tool. This tool features a visual CBH adjustment component that shows a 2D profile plot of the tree point cloud, and suggests a CBH value for user approval or adjustment. To evaluate accuracy, in situ measured CBH data from five forest plots in Germany and Hungary with varied species compositions were used. ALS data were collected during leaf-off conditions for the two Hungarian plots and during leaf-on conditions for the three German plots. Leaf-off terrestrial laser-scanned data from individual trees were also used in the accuracy assessment. A sensitivity analysis using random point decimation was conducted on the terrestrial laser-scanned data to assess treecbh’s sensitivity to point density. The initial results exhibited matching rates of 45% and 60% for leaf-off ALS plots, which significantly improved to 71% and 77%, respectively, when using the visual CBH adjustment feature of the tool. The leaf-on ALS results demonstrated matching rates between 24% and 33%, whereas the CBHs of individual terrestrial laser-scanned trees could be detected with 93% accuracy in visual mode. It was observed that treecbh operates effectively when the input ALS data have a minimum point density of 20 pts/${text{m}}^2$, with its optimal performance achieved at 110 pts/${text{m}}^2$. These findings indicated treecbh’s sensitivity to ALS data quality, scanning season (leaf-on and leaf-off), and point density. This sensitivity can be effectively mitigated in the case of leaf-off ALS data by utilizing the visual CBH adjustment feature of the tool.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"13 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-08-30DOI: 10.1093/forestry/cpae043
Emilia Zegadło, Piotr Zegadło, Elżbieta Jancewicz
Importance of coarse woody debris (CWD) in habitat use of small mammals has not been thoroughly explored, especially for European species. Moreover, despite the growing awareness about the need for protecting CWD resources in forests, their amount is usually quantified with regard to current or desired volume. The area of forest floor covered by CWD is rarely considered, despite its potential importance for habitat use of small mammals. Over a period of three summer seasons (4800 trap-nights), we examined the populations of yellow-necked mouse Apodemus flavicollis and bank vole Clethrionomys glareolus through capture-mark-recapture trapping at three 1-hectare study sites, including both managed forests and a nature reserve in Białowieża Forest, Poland. We applied generalized linear mixed models on a sample of 236 adult individuals of yellow-necked mouse and 173 adult individuals of bank vole to establish that the access to CWD is a significant aspect of their habitat use. Our results suggest that both species prefer a certain minimum amount of CWD. After accounting for different aspects of forest undergrowth, we established that bank vole more frequently used areas with a relatively large amount of CWD (threshold of 0.75 m$^{3}$ CWD per 100 m$^{2}$), together with a propensity to choose areas with debris in the later stages of decay. Yellow-necked mouse was found more frequently in areas with at least 1.5 m$^{2}$ of CWD. We suggest that manipulating CWD distribution, or possibly vegetation characteristics, could be a strategy for managing the abundance and distribution of rodents in forest stands—especially when both CWD volume and coverage are taken into account.
{"title":"Impact of coarse woody debris on habitat use of two sympatric rodent species in the temperate Białowieża Forest","authors":"Emilia Zegadło, Piotr Zegadło, Elżbieta Jancewicz","doi":"10.1093/forestry/cpae043","DOIUrl":"https://doi.org/10.1093/forestry/cpae043","url":null,"abstract":"Importance of coarse woody debris (CWD) in habitat use of small mammals has not been thoroughly explored, especially for European species. Moreover, despite the growing awareness about the need for protecting CWD resources in forests, their amount is usually quantified with regard to current or desired volume. The area of forest floor covered by CWD is rarely considered, despite its potential importance for habitat use of small mammals. Over a period of three summer seasons (4800 trap-nights), we examined the populations of yellow-necked mouse Apodemus flavicollis and bank vole Clethrionomys glareolus through capture-mark-recapture trapping at three 1-hectare study sites, including both managed forests and a nature reserve in Białowieża Forest, Poland. We applied generalized linear mixed models on a sample of 236 adult individuals of yellow-necked mouse and 173 adult individuals of bank vole to establish that the access to CWD is a significant aspect of their habitat use. Our results suggest that both species prefer a certain minimum amount of CWD. After accounting for different aspects of forest undergrowth, we established that bank vole more frequently used areas with a relatively large amount of CWD (threshold of 0.75 m$^{3}$ CWD per 100 m$^{2}$), together with a propensity to choose areas with debris in the later stages of decay. Yellow-necked mouse was found more frequently in areas with at least 1.5 m$^{2}$ of CWD. We suggest that manipulating CWD distribution, or possibly vegetation characteristics, could be a strategy for managing the abundance and distribution of rodents in forest stands—especially when both CWD volume and coverage are taken into account.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"49 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-08-06DOI: 10.1093/forestry/cpae040
Matt Combes, Joan Webber, Lynne Boddy
Hymenoscyphus fraxineus is an introduced ascomycete fungus which causes ash dieback and has resulted in widespread mortality of ash throughout Europe. Although H. fraxineus has been present on the continent for at least four decades, it was not identified until 2006. The first record of the pathogen in Britain came in 2012 although it was probably present a decade earlier. The most common host European ash (Fraxinus excelsior L.) is economically and ecologically important to Britain where the cost of ash dieback is estimated at billions of pounds. The impact of ash dieback has stimulated a major research response which we review with the aim of providing up-to-date information relevant to Britain and identifying knowledge gaps where research would contribute to improved disease mitigation. Hymenoscyphus fraxineus is an outcrossing fungus with high genotypic diversity; ascospores produced via sexual reproduction are critical to aerial dispersal and infection. Temperature, moisture, and ground cover influence pathogen fruit body development, the timing of ascospore release, and extent of ascospore germination; they also interact together to affect the likelihood of infection. In addition, stand characteristics, including tree density, tree height, and landscape fragmentation, affect disease dynamics with increased disease severity on moist sites with high ash density. Efforts at finding natural resistance in ash have identified genetic markers associated with disease tolerance, and gene expression analysis is providing insights into the basis of that resistance. Mainland European findings indicate that ash dieback makes trees more vulnerable to other pathogens, whilst endophytes in the ash phyllosphere can suppress infection by H. fraxineus. Possible tools for long-term control of ash dieback include (1) deployment of resistant ash, (2) quantitatively informed management practices based on microclimate models and better understanding of the pathogen life cycle, and (3) manipulation of biocontrol agents from the ash microbiome or pathogen mycoviruses.
fraxineus 真菌是一种外来的子囊菌,会导致白蜡树枯死,并造成欧洲各地白蜡树大面积死亡。虽然 H. fraxineus 在欧洲大陆至少存在了 40 年,但直到 2006 年才被发现。该病原体在英国的首次记录是在 2012 年,尽管它很可能在十年前就已经存在。最常见的寄主欧洲白蜡(Fraxinus excelsior L.)对英国具有重要的经济和生态意义,白蜡树枯死造成的损失估计高达数十亿英镑。白蜡树枯死的影响引发了一项重大研究,我们对这项研究进行了回顾,目的是提供与英国相关的最新信息,并找出知识差距,以便通过研究改善病害缓解工作。白蜡疫霉菌(Hymenoscyphus fraxineus)是一种外交真菌,具有高度的基因型多样性;通过有性生殖产生的 ascospores 对空中传播和感染至关重要。温度、湿度和地面覆盖会影响病原体子实体的发育、腹孢子释放的时间和腹孢子发芽的程度;它们还会相互作用,影响感染的可能性。此外,林分特征(包括树木密度、树高和景观破碎化)也会影响病害动态,在白蜡树密度高的潮湿地区,病害的严重程度会增加。为寻找白蜡树的天然抗病性所做的努力已经确定了与疾病耐受性相关的遗传标记,基因表达分析正在为了解这种抗病性的基础提供帮助。欧洲大陆的研究结果表明,白蜡树的枯萎病使树木更容易受到其他病原体的侵害,而白蜡树叶球中的内生菌可以抑制 H. fraxineus 的感染。长期控制白蜡树枯梢病的可能手段包括:(1)种植抗性白蜡树;(2)根据小气候模型和对病原体生命周期的更好了解,采取定量的管理措施;(3)利用白蜡树微生物组或病原体霉菌病毒中的生物控制剂。
{"title":"Current understanding and future prospects for ash dieback disease with a focus on Britain","authors":"Matt Combes, Joan Webber, Lynne Boddy","doi":"10.1093/forestry/cpae040","DOIUrl":"https://doi.org/10.1093/forestry/cpae040","url":null,"abstract":"Hymenoscyphus fraxineus is an introduced ascomycete fungus which causes ash dieback and has resulted in widespread mortality of ash throughout Europe. Although H. fraxineus has been present on the continent for at least four decades, it was not identified until 2006. The first record of the pathogen in Britain came in 2012 although it was probably present a decade earlier. The most common host European ash (Fraxinus excelsior L.) is economically and ecologically important to Britain where the cost of ash dieback is estimated at billions of pounds. The impact of ash dieback has stimulated a major research response which we review with the aim of providing up-to-date information relevant to Britain and identifying knowledge gaps where research would contribute to improved disease mitigation. Hymenoscyphus fraxineus is an outcrossing fungus with high genotypic diversity; ascospores produced via sexual reproduction are critical to aerial dispersal and infection. Temperature, moisture, and ground cover influence pathogen fruit body development, the timing of ascospore release, and extent of ascospore germination; they also interact together to affect the likelihood of infection. In addition, stand characteristics, including tree density, tree height, and landscape fragmentation, affect disease dynamics with increased disease severity on moist sites with high ash density. Efforts at finding natural resistance in ash have identified genetic markers associated with disease tolerance, and gene expression analysis is providing insights into the basis of that resistance. Mainland European findings indicate that ash dieback makes trees more vulnerable to other pathogens, whilst endophytes in the ash phyllosphere can suppress infection by H. fraxineus. Possible tools for long-term control of ash dieback include (1) deployment of resistant ash, (2) quantitatively informed management practices based on microclimate models and better understanding of the pathogen life cycle, and (3) manipulation of biocontrol agents from the ash microbiome or pathogen mycoviruses.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"22 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141935468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-08-05DOI: 10.1093/forestry/cpae042
Martina Komárková, Jiří Čáp, Olga Trčková, Jaroslav Dostál, Pavlína Máchová
Pinus mugo (dwarf mountain pine) communities in the protected area of Krkonoše National Park are extremely valuable. After extensive deforestation during the sixteenth to nineteenth centuries, P. mugo recovered naturally in some parts of the Giant Mountains, and in some places imported seeds were likely used for reforestation. To distinguish between native and possibly introduced local P. mugo populations, genetic variations between 12 populations from the Czech Sudeten part of the Giant Mountains and between the two populations from the Tatra Mountains were analysed using 12 nuclear microsatellite markers (nuclear simple sequence repeats). Based on the simple sequence repeat data, 146 alleles were found, and Shannon’s information index, number of private alleles, and expected heterozygosity (HE) of populations averaged 1.12, 0.16, and 0.53, respectively. Analysis of molecular variance indicated that most of the variation was detected within populations. Low levels of genetic differentiation were also observed (average FST = 0.023). The population structure was examined by Bayesian clustering. The results of STRUCTURE analysis confirmed that the introduced populations were different from the autochthonous populations. Some of the introduced Czech Sudeten populations had similar genetic structure as the more distant native populations from the Tatra Mountains. Our results provide important genetic information for the reconstruction of natural communities in the Giant Mountains.
{"title":"Comparison of population genetic structure of Pinus mugo Turra forest stands in the Giant Mountains by analysis of nSSR molecular marker data","authors":"Martina Komárková, Jiří Čáp, Olga Trčková, Jaroslav Dostál, Pavlína Máchová","doi":"10.1093/forestry/cpae042","DOIUrl":"https://doi.org/10.1093/forestry/cpae042","url":null,"abstract":"Pinus mugo (dwarf mountain pine) communities in the protected area of Krkonoše National Park are extremely valuable. After extensive deforestation during the sixteenth to nineteenth centuries, P. mugo recovered naturally in some parts of the Giant Mountains, and in some places imported seeds were likely used for reforestation. To distinguish between native and possibly introduced local P. mugo populations, genetic variations between 12 populations from the Czech Sudeten part of the Giant Mountains and between the two populations from the Tatra Mountains were analysed using 12 nuclear microsatellite markers (nuclear simple sequence repeats). Based on the simple sequence repeat data, 146 alleles were found, and Shannon’s information index, number of private alleles, and expected heterozygosity (HE) of populations averaged 1.12, 0.16, and 0.53, respectively. Analysis of molecular variance indicated that most of the variation was detected within populations. Low levels of genetic differentiation were also observed (average FST = 0.023). The population structure was examined by Bayesian clustering. The results of STRUCTURE analysis confirmed that the introduced populations were different from the autochthonous populations. Some of the introduced Czech Sudeten populations had similar genetic structure as the more distant native populations from the Tatra Mountains. Our results provide important genetic information for the reconstruction of natural communities in the Giant Mountains.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"48 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141935469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-08-01DOI: 10.1093/forestry/cpae041
Alberto Udali, Woodam Chung, Bruce Talbot, Stefano Grigolato
Dead woody materials are naturally part of the forest ecosystem introduced through the process of tree mortality or intentionally through stand management practices which result in harvesting residues. The management of harvesting residues includes a range of solutions that vary from site to site, from context to context. The purpose of this review is to determine the current state-of-the-art of harvesting residue management treatments at a global scale. Our review indicates that there are few studies that compare residue management and treatment options, considering the variety of impacts and effects that can be generated. This is surprising as residue management affects residue quantity and distribution and is relevant for numerous ecological processes. The retention of fine and coarse residues can generate positive effects and impacts on various aspects of forest ecosystems including (i) biodiversity, by promoting stand regeneration and providing habitats for fauna at different levels; (ii) soil properties, by decreasing the risk of erosion and soil compaction while retaining moisture at ground level; and (iii) soil nutrients, by replenishing C, N, and micronutrient stocks. On the contrary, harvesting residues can provide material for bioenergy production and potentially other fiber industries. The removal of residues can also reduce wildfire risks and dampen insect outbreak dynamics. In this work, we provide a general outline of the role of residues as well as a summary of current management options adopted around the world. The intention of the work is to provide an information base for stakeholders including forest managers and policymakers in identifying and assessing potential alternatives for their current local practices.
{"title":"Managing harvesting residues: a systematic review of management treatments around the world","authors":"Alberto Udali, Woodam Chung, Bruce Talbot, Stefano Grigolato","doi":"10.1093/forestry/cpae041","DOIUrl":"https://doi.org/10.1093/forestry/cpae041","url":null,"abstract":"Dead woody materials are naturally part of the forest ecosystem introduced through the process of tree mortality or intentionally through stand management practices which result in harvesting residues. The management of harvesting residues includes a range of solutions that vary from site to site, from context to context. The purpose of this review is to determine the current state-of-the-art of harvesting residue management treatments at a global scale. Our review indicates that there are few studies that compare residue management and treatment options, considering the variety of impacts and effects that can be generated. This is surprising as residue management affects residue quantity and distribution and is relevant for numerous ecological processes. The retention of fine and coarse residues can generate positive effects and impacts on various aspects of forest ecosystems including (i) biodiversity, by promoting stand regeneration and providing habitats for fauna at different levels; (ii) soil properties, by decreasing the risk of erosion and soil compaction while retaining moisture at ground level; and (iii) soil nutrients, by replenishing C, N, and micronutrient stocks. On the contrary, harvesting residues can provide material for bioenergy production and potentially other fiber industries. The removal of residues can also reduce wildfire risks and dampen insect outbreak dynamics. In this work, we provide a general outline of the role of residues as well as a summary of current management options adopted around the world. The intention of the work is to provide an information base for stakeholders including forest managers and policymakers in identifying and assessing potential alternatives for their current local practices.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"55 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141885483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-23DOI: 10.1093/forestry/cpae034
Vicent A Ribas-Costa, Aitor Gastón, Rachel L Cook
Accurate quantification and mapping of forest productivity are critical to understanding and managing forest ecosystems. Local LiDAR or photogrammetric surveys have been used to obtain reliable estimates of canopy heights, yet these acquisitions can entail substantial expenses. Therefore, we developed models using freely available US Geological survey (USGS) LiDAR data for prediction of dominant height to map site index across loblolly pine (Pinus taeda L.) plantations in the southeastern US. We used 2017–2020 national USGS 3D Elevation Program LiDAR acquisitions and explored how different height percentiles, grid output resolutions, time difference between LiDAR and ground acquisitions, tree height, and dominant height definition affected the proposed model. We built the dominant height models using 1301 ground plots. The final regression model was constructed with the 95th percentile of the height distribution of the first returns above-ground and had values of R2 = 0.89, RMSE = 1.55 m, and RRMSE = 7.66 per cent at a 20-m pixel grid, yet all the examined percentile-resolution combinations were acceptable. No effect evidence was found for time difference when the flight was less than 4 months in advance or after the ground measurement, and it was also found independent of pulse density when this variable was lower than 9.5 pulses m−2. Using the recorded age of the plantations, we assessed the error propagation when translating dominant height to site index in two site index models, obtaining an RRMSE lower than 10 per cent in both. We found that USGS LiDAR acquisitions can be reliably used to map dominant height at a large scale, and consequently used to map forest productivity when age is known. This ability adds more value to a tool proven widely applicable in time and space and offers a great opportunity for stakeholders in different fields of use.
{"title":"Modeling dominant height with USGS 3DEP LiDAR to determine site index in even-aged loblolly pine (Pinus taeda L.) plantations in the southeastern US","authors":"Vicent A Ribas-Costa, Aitor Gastón, Rachel L Cook","doi":"10.1093/forestry/cpae034","DOIUrl":"https://doi.org/10.1093/forestry/cpae034","url":null,"abstract":"Accurate quantification and mapping of forest productivity are critical to understanding and managing forest ecosystems. Local LiDAR or photogrammetric surveys have been used to obtain reliable estimates of canopy heights, yet these acquisitions can entail substantial expenses. Therefore, we developed models using freely available US Geological survey (USGS) LiDAR data for prediction of dominant height to map site index across loblolly pine (Pinus taeda L.) plantations in the southeastern US. We used 2017–2020 national USGS 3D Elevation Program LiDAR acquisitions and explored how different height percentiles, grid output resolutions, time difference between LiDAR and ground acquisitions, tree height, and dominant height definition affected the proposed model. We built the dominant height models using 1301 ground plots. The final regression model was constructed with the 95th percentile of the height distribution of the first returns above-ground and had values of R2 = 0.89, RMSE = 1.55 m, and RRMSE = 7.66 per cent at a 20-m pixel grid, yet all the examined percentile-resolution combinations were acceptable. No effect evidence was found for time difference when the flight was less than 4 months in advance or after the ground measurement, and it was also found independent of pulse density when this variable was lower than 9.5 pulses m−2. Using the recorded age of the plantations, we assessed the error propagation when translating dominant height to site index in two site index models, obtaining an RRMSE lower than 10 per cent in both. We found that USGS LiDAR acquisitions can be reliably used to map dominant height at a large scale, and consequently used to map forest productivity when age is known. This ability adds more value to a tool proven widely applicable in time and space and offers a great opportunity for stakeholders in different fields of use.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"16 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141776028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-18DOI: 10.1093/forestry/cpae039
Inês Gomes Marques, Cristina Vieites-Blanco, Maria J Barrento, José N Semedo, Ana P Rodrigues, Paula Scotti-Campos, M Angela Martín, Alejandro Solla, Teresa S David, Patricia M Rodríguez-González
The recent taxonomic distinction between the European common alder species Alnus glutinosa and A. lusitanica strengthens the need for studies on phenotypic and genetic variation. Understanding such variations requires the use of populations encompassing the total latitudinal distribution and environmental envelope of the distribution range of A. glutinosa and A. lusitanica. This study aims to describe the genetic diversity and assess the phenology, morphology, physiology and biochemistry of alder seedlings from populations reaching out to the latitudinal extremes of both species. We grew 1579 2-year-old seedlings from seven A. glutinosa and six A. lusitanica populations in a common garden in Oeiras, Portugal. By using simple sequence repeat markers, two genetically distinct groups in A. glutinosa and three in A. lusitanica were identified. The species presented marked morphological and biochemical differences. The southern populations of A. lusitanica showed higher genetic diversity than A. glutinosa populations. Significant associations between four alleles from three loci, and one morphological and three biochemical traits were detected in several genetic groups from both alder species. Traits from southern populations of A. lusitanica were associated with low water availability. Inter-specific trait variation and association of traits with molecular markers suggest that A. lusitanica might have an adaptive advantage if subjected to drought and heat stressors. This study strengthens the recent taxonomical differentiation between the two species and emphasizes the need for preserving southern A. lusitanica populations and their genetic diversity in Mediterranean riparian corridors.
最近,欧洲常见桤木物种桤木(Alnus glutinosa)和桤木(A. lusitanica)在分类学上被区分开来,这加强了对表型和遗传变异进行研究的必要性。要了解这些变异,就需要利用涵盖桤木(A. glutinosa)和桤木(A. lusitanica)分布区总纬度分布和环境包络的种群。本研究旨在描述桤木幼苗的遗传多样性,并对其物候学、形态学、生理学和生物化学进行评估。我们在葡萄牙奥伊拉斯(Oeiras)的一个普通花园中培育了 1579 株 2 岁桤木幼苗,分别来自 7 个桤木种群和 6 个桤木种群。通过使用简单序列重复标记,我们在 A. glutinosa 和 A. lusitanica 中分别鉴定出了两个不同的基因组。这些物种在形态和生化方面存在明显差异。南部的 A. lusitanica 种群比 A. glutinosa 种群表现出更高的遗传多样性。在两个桤木物种的几个遗传组中,发现三个位点的四个等位基因与一个形态特征和三个生化特征之间存在显著关联。A. lusitanica南部种群的性状与低水分可用性有关。种间性状变异以及性状与分子标记的关联表明,如果受到干旱和高温胁迫,A. lusitanica 可能具有适应优势。这项研究加强了这两个物种最近在分类学上的区分,并强调了在地中海河岸走廊保护南部 A. lusitanica 种群及其遗传多样性的必要性。
{"title":"Phenotypic variation and genetic diversity in European Alnus species","authors":"Inês Gomes Marques, Cristina Vieites-Blanco, Maria J Barrento, José N Semedo, Ana P Rodrigues, Paula Scotti-Campos, M Angela Martín, Alejandro Solla, Teresa S David, Patricia M Rodríguez-González","doi":"10.1093/forestry/cpae039","DOIUrl":"https://doi.org/10.1093/forestry/cpae039","url":null,"abstract":"The recent taxonomic distinction between the European common alder species Alnus glutinosa and A. lusitanica strengthens the need for studies on phenotypic and genetic variation. Understanding such variations requires the use of populations encompassing the total latitudinal distribution and environmental envelope of the distribution range of A. glutinosa and A. lusitanica. This study aims to describe the genetic diversity and assess the phenology, morphology, physiology and biochemistry of alder seedlings from populations reaching out to the latitudinal extremes of both species. We grew 1579 2-year-old seedlings from seven A. glutinosa and six A. lusitanica populations in a common garden in Oeiras, Portugal. By using simple sequence repeat markers, two genetically distinct groups in A. glutinosa and three in A. lusitanica were identified. The species presented marked morphological and biochemical differences. The southern populations of A. lusitanica showed higher genetic diversity than A. glutinosa populations. Significant associations between four alleles from three loci, and one morphological and three biochemical traits were detected in several genetic groups from both alder species. Traits from southern populations of A. lusitanica were associated with low water availability. Inter-specific trait variation and association of traits with molecular markers suggest that A. lusitanica might have an adaptive advantage if subjected to drought and heat stressors. This study strengthens the recent taxonomical differentiation between the two species and emphasizes the need for preserving southern A. lusitanica populations and their genetic diversity in Mediterranean riparian corridors.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"51 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141740146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-11DOI: 10.1093/forestry/cpae038
Eike Reinosch, Julian Backa, Petra Adler, Janik Deutscher, Philipp Eisnecker, Karina Hoffmann, Niklas Langner, Martin Puhm, Marius Rüetschi, Christoph Straub, Lars T Waser, Jens Wiesehahn, Katja Oehmichen
Monitoring forest areas with satellite data has become a vital tool to derive information on disturbances in European forests at large scales. An extensive validation of generated maps is essential to evaluate their potential and limitations in detecting various disturbance patterns. Here, we present the validation results of forest disturbance maps generated for four study areas in Germany using Sentinel-2 data from 2018 to 2022. We apply a time series filtering method to map annual forest disturbances larger than 0.1 ha based on spectral clustering and annual change magnitude. The presented method is part of a research study to design a precursor for a national German forest disturbance monitoring system. In this context, annual forest change areas are used to estimate affected timber volume and related economic losses. To better understand the thematic accuracies and the reliability of the area estimates, we performed an independent and extensive validation of the annual product using 20 validation sets embedded in our four study areas and comprising a total of 11 019 sample points. The collected reference datasets are based on an expert interpretation of high-resolution aerial and satellite imagery, including information on the dominant tree species, disturbance cause, and disturbance severity level. Our forest disturbance map achieves an overall accuracy of 99.1 ± 0.1% in separating disturbed from undisturbed forest. This is mainly indicative of the accuracy for undisturbed forest, as that class covers 97.2% of the total forest area. For the disturbed forest class, the user’s accuracy is 84.4 ± 2.0% and producer’s accuracy is 85.1 ± 3.4% for 2018 to 2022. The similar user’s and producer’s accuracies indicate that the total disturbance area is estimated accurately. However, for 2022, we observe an overestimation of the total disturbance extent, which we attribute to the high drought stress in that year leading to false detections, especially around forest edges. The accuracy varies widely among validation sets and seems related to the disturbance cause, the disturbance severity, and the disturbance patch size. User’s accuracies range from 31.0 ± 8.4% to 98.8 ± 1.3%, while producer’s accuracies range from 60.5 ± 37.3% to 100.0 ± 0.0% across the validation sets. These variations highlight that the accuracy of a single local validation set is not representative of a region with a large diversity of disturbance patterns, such as Germany. This emphasizes the need to assess the accuracies of large-scale disturbance products in as many different study areas as possible, to cover different patch sizes, disturbance severities, and disturbance causes.
{"title":"Detailed validation of large-scale Sentinel-2-based forest disturbance maps across Germany","authors":"Eike Reinosch, Julian Backa, Petra Adler, Janik Deutscher, Philipp Eisnecker, Karina Hoffmann, Niklas Langner, Martin Puhm, Marius Rüetschi, Christoph Straub, Lars T Waser, Jens Wiesehahn, Katja Oehmichen","doi":"10.1093/forestry/cpae038","DOIUrl":"https://doi.org/10.1093/forestry/cpae038","url":null,"abstract":"Monitoring forest areas with satellite data has become a vital tool to derive information on disturbances in European forests at large scales. An extensive validation of generated maps is essential to evaluate their potential and limitations in detecting various disturbance patterns. Here, we present the validation results of forest disturbance maps generated for four study areas in Germany using Sentinel-2 data from 2018 to 2022. We apply a time series filtering method to map annual forest disturbances larger than 0.1 ha based on spectral clustering and annual change magnitude. The presented method is part of a research study to design a precursor for a national German forest disturbance monitoring system. In this context, annual forest change areas are used to estimate affected timber volume and related economic losses. To better understand the thematic accuracies and the reliability of the area estimates, we performed an independent and extensive validation of the annual product using 20 validation sets embedded in our four study areas and comprising a total of 11 019 sample points. The collected reference datasets are based on an expert interpretation of high-resolution aerial and satellite imagery, including information on the dominant tree species, disturbance cause, and disturbance severity level. Our forest disturbance map achieves an overall accuracy of 99.1 ± 0.1% in separating disturbed from undisturbed forest. This is mainly indicative of the accuracy for undisturbed forest, as that class covers 97.2% of the total forest area. For the disturbed forest class, the user’s accuracy is 84.4 ± 2.0% and producer’s accuracy is 85.1 ± 3.4% for 2018 to 2022. The similar user’s and producer’s accuracies indicate that the total disturbance area is estimated accurately. However, for 2022, we observe an overestimation of the total disturbance extent, which we attribute to the high drought stress in that year leading to false detections, especially around forest edges. The accuracy varies widely among validation sets and seems related to the disturbance cause, the disturbance severity, and the disturbance patch size. User’s accuracies range from 31.0 ± 8.4% to 98.8 ± 1.3%, while producer’s accuracies range from 60.5 ± 37.3% to 100.0 ± 0.0% across the validation sets. These variations highlight that the accuracy of a single local validation set is not representative of a region with a large diversity of disturbance patterns, such as Germany. This emphasizes the need to assess the accuracies of large-scale disturbance products in as many different study areas as possible, to cover different patch sizes, disturbance severities, and disturbance causes.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"79 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141609256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-10DOI: 10.1093/forestry/cpae037
Vadim Saraev, Anssi Ahtikoski, Richard Whittet, Duncan Ray
The deployment of improved forest reproductive material (FRM) selected to yield greater timber volume and quality than unimproved material could help to maintain productive, sustainable, and resilient forests and increase resistance to abiotic and biotic threats under extreme climate change events. In Scotland, Scots pine (Pinus sylvestris L.) is a productive species that aligns with these objectives. However, confidence in Scots pine has been low in recent years due to damage caused by the needle blight Dothistroma septosporum. Recent provenance/progeny trials using native Scots pine material from the Caledonian pine woods indicate a favourable genetic correlation between growth and resistance to D. septosporum, suggesting that simultaneous improvements are possible. The Scots pine breeding programme in Scotland was closed in 2002. Here, we present an economic case for reopening the breeding programme to further improve Scots pine FRM. Specifically, we evaluate the costs and potential benefits of supporting a new programme. We conduct an analysis using three improvement scenarios using a Faustmann formula (amended with thinnings) to maximize the land expectation value. Our results indicate that further improvement of Scots pine FRM would be cost-effective, outperforming the current Scots pine timber production and financial outcomes. The analysis shows that the Central scenario’s land expectation value rises by £883 ha−1 compared to the baseline of £79 ha−1, assuming a 3.5% interest rate. We employed both annuity calculations and a break-even analysis to show improved FRM could maintain a breeding programme investment of £3.5 million per year over a 30-year period with a break-even cost threshold increase of ~52% for purchasing improved planting materials from £0.33 to £0.50 per seedling. In conclusion, the study provides economic evidence of the commercial benefits for reopening the Scots pine breeding programme to increase timber production and financial returns.
{"title":"Economic evaluation of reopening a dormant tree improvement programme: a case study with Scots pine in Scotland","authors":"Vadim Saraev, Anssi Ahtikoski, Richard Whittet, Duncan Ray","doi":"10.1093/forestry/cpae037","DOIUrl":"https://doi.org/10.1093/forestry/cpae037","url":null,"abstract":"The deployment of improved forest reproductive material (FRM) selected to yield greater timber volume and quality than unimproved material could help to maintain productive, sustainable, and resilient forests and increase resistance to abiotic and biotic threats under extreme climate change events. In Scotland, Scots pine (Pinus sylvestris L.) is a productive species that aligns with these objectives. However, confidence in Scots pine has been low in recent years due to damage caused by the needle blight Dothistroma septosporum. Recent provenance/progeny trials using native Scots pine material from the Caledonian pine woods indicate a favourable genetic correlation between growth and resistance to D. septosporum, suggesting that simultaneous improvements are possible. The Scots pine breeding programme in Scotland was closed in 2002. Here, we present an economic case for reopening the breeding programme to further improve Scots pine FRM. Specifically, we evaluate the costs and potential benefits of supporting a new programme. We conduct an analysis using three improvement scenarios using a Faustmann formula (amended with thinnings) to maximize the land expectation value. Our results indicate that further improvement of Scots pine FRM would be cost-effective, outperforming the current Scots pine timber production and financial outcomes. The analysis shows that the Central scenario’s land expectation value rises by £883 ha−1 compared to the baseline of £79 ha−1, assuming a 3.5% interest rate. We employed both annuity calculations and a break-even analysis to show improved FRM could maintain a breeding programme investment of £3.5 million per year over a 30-year period with a break-even cost threshold increase of ~52% for purchasing improved planting materials from £0.33 to £0.50 per seedling. In conclusion, the study provides economic evidence of the commercial benefits for reopening the Scots pine breeding programme to increase timber production and financial returns.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"36 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141587720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-10DOI: 10.1093/forestry/cpae036
Arne Pinnschmidt, Rasoul Yousefpour, Anja Nölte, Marc Hanewinkel
Reforestation of tropical forests is crucial to mitigate the climate crisis and restore ecosystems. However, past efforts have been criticized for establishing monoculture timber plantations with exotic tree species. Close-to-nature (CTN) practices aim to minimize negative forest management impacts on forests ecosystems by mimicking natural dynamics. So far, CTN management practices are rarely applied in tropical plantation forestry. This study evaluates the economic, carbon sequestration, and biodiversity potential of CTN management in tropical mixed-species plantations in Central America using a simulation-optimization approach. To our knowledge, this study is the first to assess the potential of tropical CTN-managed plantations on the basis of detailed process-based forest growth simulations. CTN practices such as selective harvesting, retention forestry, and shelterwood cutting of mixed-species stands were compared to even-aged mixtures and conventional monoculture practices. Results showed that CTN management was economically viable for certain species mixtures and management practices at an 8 % discount rate and had the potential to increase carbon storage and biodiversity in the modeled plantations. At current carbon prices, CTN-managed plantations may only become financially competitive with monocultures, if monocultures are excluded from carbon certification schemes that increasingly aim at co-producing non-carbon benefits like biodiversity conservation. If carbon prices increase, the sale of carbon credits could finance the transformation of monocultures to CTN-managed mixed-species stands. The competitiveness of CTN management could also be improved through performance-based biodiversity payments, such as the sale of biodiversity credits.
{"title":"Close-to-nature management of tropical timber plantations is economically viable and provides biodiversity benefits","authors":"Arne Pinnschmidt, Rasoul Yousefpour, Anja Nölte, Marc Hanewinkel","doi":"10.1093/forestry/cpae036","DOIUrl":"https://doi.org/10.1093/forestry/cpae036","url":null,"abstract":"Reforestation of tropical forests is crucial to mitigate the climate crisis and restore ecosystems. However, past efforts have been criticized for establishing monoculture timber plantations with exotic tree species. Close-to-nature (CTN) practices aim to minimize negative forest management impacts on forests ecosystems by mimicking natural dynamics. So far, CTN management practices are rarely applied in tropical plantation forestry. This study evaluates the economic, carbon sequestration, and biodiversity potential of CTN management in tropical mixed-species plantations in Central America using a simulation-optimization approach. To our knowledge, this study is the first to assess the potential of tropical CTN-managed plantations on the basis of detailed process-based forest growth simulations. CTN practices such as selective harvesting, retention forestry, and shelterwood cutting of mixed-species stands were compared to even-aged mixtures and conventional monoculture practices. Results showed that CTN management was economically viable for certain species mixtures and management practices at an 8 % discount rate and had the potential to increase carbon storage and biodiversity in the modeled plantations. At current carbon prices, CTN-managed plantations may only become financially competitive with monocultures, if monocultures are excluded from carbon certification schemes that increasingly aim at co-producing non-carbon benefits like biodiversity conservation. If carbon prices increase, the sale of carbon credits could finance the transformation of monocultures to CTN-managed mixed-species stands. The competitiveness of CTN management could also be improved through performance-based biodiversity payments, such as the sale of biodiversity credits.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":"10 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141587721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}