Pub Date : 2020-06-01DOI: 10.1093/forestry/cpaa016
A. Hekkala, S. Kärvemo, Martijn Versluijs, J. Weslien, C. Björkman, T. Löfroth, J. Hjältén
The restoration of forest structure and function is increasingly being used in boreal forests in order to halt the loss of biodiversity. Often ecological restoration is aimed at increasing the volume of dead and dying trees to enhance the biodiversity of deadwood-dependent organisms, but it may also increase population sizes of pest bark beetle species, even several years following restoration. Herein, we used a large-scale restoration experiment in Northern Sweden to assess the 5 years post-restoration effects of restorative gap cutting and prescribed burning on the populations of a set of economically harmful pest bark beetles (Ips typographus, Polygraphus poligraphus, Tomicus piniperda and Pityogenes chalcographus) and the most important predators of bark beetles, Thanasimus spp. In addition, we assessed the effects of forest stand characteristics at stand and landscape scale on the abundance of I. typographus. Five years post-restoration, gap-cut stands supported the highest abundances of P. poligraphus and contained the highest count of spruce trees newly attacked by bark beetles. By contrast, prescribed burning generally sustained the lowest abundances of pest bark beetles, especially I. typographus and P. poligraphus, and the highest abundance of their natural predators Thanasimus spp. The population abundance of I. typographus was also positively affected by the area of clear cuts within a 500 m radius from the stand. In conclusion, prescribed burning appears to be a safer method for ecological restoration than gap cutting in the long-term. According to our results, a risk of a local bark beetle outbreak still remains 5 years following the initiation of ecological restoration treatments on spruce-dominated mature gap-cut stands.
{"title":"Ecological restoration for biodiversity conservation triggers response of bark beetle pests and their natural predators","authors":"A. Hekkala, S. Kärvemo, Martijn Versluijs, J. Weslien, C. Björkman, T. Löfroth, J. Hjältén","doi":"10.1093/forestry/cpaa016","DOIUrl":"https://doi.org/10.1093/forestry/cpaa016","url":null,"abstract":"\u0000 The restoration of forest structure and function is increasingly being used in boreal forests in order to halt the loss of biodiversity. Often ecological restoration is aimed at increasing the volume of dead and dying trees to enhance the biodiversity of deadwood-dependent organisms, but it may also increase population sizes of pest bark beetle species, even several years following restoration. Herein, we used a large-scale restoration experiment in Northern Sweden to assess the 5 years post-restoration effects of restorative gap cutting and prescribed burning on the populations of a set of economically harmful pest bark beetles (Ips typographus, Polygraphus poligraphus, Tomicus piniperda and Pityogenes chalcographus) and the most important predators of bark beetles, Thanasimus spp. In addition, we assessed the effects of forest stand characteristics at stand and landscape scale on the abundance of I. typographus. Five years post-restoration, gap-cut stands supported the highest abundances of P. poligraphus and contained the highest count of spruce trees newly attacked by bark beetles. By contrast, prescribed burning generally sustained the lowest abundances of pest bark beetles, especially I. typographus and P. poligraphus, and the highest abundance of their natural predators Thanasimus spp. The population abundance of I. typographus was also positively affected by the area of clear cuts within a 500 m radius from the stand. In conclusion, prescribed burning appears to be a safer method for ecological restoration than gap cutting in the long-term. According to our results, a risk of a local bark beetle outbreak still remains 5 years following the initiation of ecological restoration treatments on spruce-dominated mature gap-cut stands.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77734835","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}
Loblolly pine (Pinus taeda L.) is one of the most widely planted tree species globally. As the reliability of estimating forest characteristics such as volume, biomass and carbon becomes more important, the necessary resources available for assessment are often insufficient to meet desired confidence levels. Small area estimation (SAE) methods were investigated for their potential to improve the precision of volume estimates in loblolly pine plantations aged 9–43. Area-level SAE models that included lidar height percentiles and stand thinning status as auxiliary information were developed to test whether precision gains could be achieved. Models that utilized both forms of auxiliary data provided larger gains in precision compared to using lidar alone. Unit-level SAE models were found to offer additional gains compared with area-level models in some cases; however, area-level models that incorporated both lidar and thinning status performed nearly as well or better. Despite their potential gains in precision, unit-level models are more difficult to apply in practice due to the need for highly accurate, spatially defined sample units and the inability to incorporate certain area-level covariates. The results of this study are of interest to those looking to reduce the uncertainty of stand parameter estimates. With improved estimate precision, managers, stakeholders and policy makers can have more confidence in resource assessments for informed decisions.
{"title":"A novel application of small area estimation in loblolly pine forest inventory","authors":"P. Green, H. Burkhart, J. Coulston, P. Radtke","doi":"10.1093/forestry/cpz073","DOIUrl":"https://doi.org/10.1093/forestry/cpz073","url":null,"abstract":"Loblolly pine (Pinus taeda L.) is one of the most widely planted tree species globally. As the reliability of estimating forest characteristics such as volume, biomass and carbon becomes more important, the necessary resources available for assessment are often insufficient to meet desired confidence levels. Small area estimation (SAE) methods were investigated for their potential to improve the precision of volume estimates in loblolly pine plantations aged 9–43. Area-level SAE models that included lidar height percentiles and stand thinning status as auxiliary information were developed to test whether precision gains could be achieved. Models that utilized both forms of auxiliary data provided larger gains in precision compared to using lidar alone. Unit-level SAE models were found to offer additional gains compared with area-level models in some cases; however, area-level models that incorporated both lidar and thinning status performed nearly as well or better. Despite their potential gains in precision, unit-level models are more difficult to apply in practice due to the need for highly accurate, spatially defined sample units and the inability to incorporate certain area-level covariates. The results of this study are of interest to those looking to reduce the uncertainty of stand parameter estimates. With improved estimate precision, managers, stakeholders and policy makers can have more confidence in resource assessments for informed decisions.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73387204","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}
J. Socha, P. Hawryło, M. Pierzchalski, K. Stereńczak, G. Krok, P. Wężyk, Luiza Tymińska-Czabańska
Reliable information concerning stand volume is fundamental to making strategic decisions in sustainable forest management. A variety of remotely sensed data and different inventory methods have been used for the estimation of forest biometric parameters. Particularly, airborne laser scanning (ALS) point clouds are widely used for the estimation of stand volume and forest biomass using an area-based approach (ABA) framework. This method relies on the reference measurements of field plots with the necessary prerequisite of a precise co-registration between ground reference plots and the corresponding ALS samples. In this research, the allometric area-based approach (AABA) is proposed in the context of stand volume estimation of Scots pine (Pinus sylvestris L.) stands. The proposed method does not require detailed information about the coordinates of the field plots. We applied Polish National Forest Inventory data from 9400 circular field plots (400 m2) to develop a plot level stand volume allometric model using two independent variables: top height (TH) and relative spacing index (RSI). The model was developed using the multiple linear regression method with a log–log transformation of variables. The hypothesis was that, the field measurements of TH and RSI could be replaced with corresponding ALS-derived metrics. It was assumed that TH could be represented by the maximum height of the ALS point cloud, while RSI can be calculated based on the number of tree crowns delineated within the ALS-derived canopy height model. Performance of the developed AABA model was compared with the semi-empirical ABASE (with two predictors: TH and RSI) and empirical ABAE (several point cloud metrics as predictors). The models were validated at the plot level using 315 forest management inventory plots (400 m2) and at the stand level using the complete field measurements from 42 Scots pine dominated forest stands in the Milicz forest district (Poland). The AABA model showed a comparable accuracy to the traditional ABA models with relatively high accuracy at the plot (relative root mean square error (RMSE) = 22.8 per cent; R2 = 0.63) and stand levels (RMSE = 17.8 per cent, R2 = 0.65). The proposed novel approach reduces time- and cost-consuming field work required for the classic ABA method, without a significant reduction in the accuracy of stand volume estimations. The AABA is potentially applicable in the context of forest management inventory without the necessity for field measurements at local scale. The transportability of the approach to other species and more complex stands needs to be explored in future studies.
{"title":"An allometric area-based approach—a cost-effective method for stand volume estimation based on ALS and NFI data","authors":"J. Socha, P. Hawryło, M. Pierzchalski, K. Stereńczak, G. Krok, P. Wężyk, Luiza Tymińska-Czabańska","doi":"10.1093/forestry/cpz062","DOIUrl":"https://doi.org/10.1093/forestry/cpz062","url":null,"abstract":"\u0000 Reliable information concerning stand volume is fundamental to making strategic decisions in sustainable forest management. A variety of remotely sensed data and different inventory methods have been used for the estimation of forest biometric parameters. Particularly, airborne laser scanning (ALS) point clouds are widely used for the estimation of stand volume and forest biomass using an area-based approach (ABA) framework. This method relies on the reference measurements of field plots with the necessary prerequisite of a precise co-registration between ground reference plots and the corresponding ALS samples. In this research, the allometric area-based approach (AABA) is proposed in the context of stand volume estimation of Scots pine (Pinus sylvestris L.) stands. The proposed method does not require detailed information about the coordinates of the field plots. We applied Polish National Forest Inventory data from 9400 circular field plots (400 m2) to develop a plot level stand volume allometric model using two independent variables: top height (TH) and relative spacing index (RSI). The model was developed using the multiple linear regression method with a log–log transformation of variables. The hypothesis was that, the field measurements of TH and RSI could be replaced with corresponding ALS-derived metrics. It was assumed that TH could be represented by the maximum height of the ALS point cloud, while RSI can be calculated based on the number of tree crowns delineated within the ALS-derived canopy height model. Performance of the developed AABA model was compared with the semi-empirical ABASE (with two predictors: TH and RSI) and empirical ABAE (several point cloud metrics as predictors). The models were validated at the plot level using 315 forest management inventory plots (400 m2) and at the stand level using the complete field measurements from 42 Scots pine dominated forest stands in the Milicz forest district (Poland). The AABA model showed a comparable accuracy to the traditional ABA models with relatively high accuracy at the plot (relative root mean square error (RMSE) = 22.8 per cent; R2 = 0.63) and stand levels (RMSE = 17.8 per cent, R2 = 0.65). The proposed novel approach reduces time- and cost-consuming field work required for the classic ABA method, without a significant reduction in the accuracy of stand volume estimations. The AABA is potentially applicable in the context of forest management inventory without the necessity for field measurements at local scale. The transportability of the approach to other species and more complex stands needs to be explored in future studies.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81270920","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}
H. Soman, A. Kizha, Bethany L. Muñoz Delgado, L. Kenefic, K. Kanoti
Felled trees with tops and branches are transported to the landing with a grapple skidder in conventional groundbased whole-tree (WT) harvesting. This method has greater potential to damage advance regeneration than those in which trees are processed at-stump. Hybrid tree-length (Hyb TL) harvesting using an stroke-boom delimber for in-woods processing might be a feasible alternative, but little is known about the production economics of this method. An experimental strip-cutting study was conducted in central Maine, US in the winter of 2018 to: (1) evaluate and compare operational productivity and costs of ground-based Hyb TL and WT methods; (2) identify factors influencing productivity of at-stump and at-landing log processing; and (3) calculate best management practice (BMP) implementation costs in WT harvesting. Time-motion data were recorded for operational phases such as felling, extraction, processing, sorting and loading; machine rates were calculated to determine productivity and costs of operations. Total cost of Hyb TL (US $17.01 m−3) was lower than that of WT ($18.38m−3). Processing costwas lower at-stump than at-landing ($2.66 and $2.73m−3 for Hyb TL and WT, respectively). This is likely due to fewer logs handled per cycle at-landing (1.2 logs per turn) compared to the number handled per cycle at-stump (1.4 logs per turn). Sensitivity analysis showed that a 30-m increase in average in-woods distance travelled by the delimber would result in a 41 per cent increase in the processing cost. Cost of BMP implementation in WT was $2.25 m−3 or $59.2 per productive machine hour. Results suggest that it is feasible to apply Hyb TL method in an industrial harvesting operation, though distance of in-woods delimber movement influences processing costs. Insights from this study will help forest managers and loggers efficiently plan and execute harvesting operations.
{"title":"Production economics: comparing hybrid tree-length with whole-tree harvesting methods","authors":"H. Soman, A. Kizha, Bethany L. Muñoz Delgado, L. Kenefic, K. Kanoti","doi":"10.1093/forestry/cpz065","DOIUrl":"https://doi.org/10.1093/forestry/cpz065","url":null,"abstract":"Felled trees with tops and branches are transported to the landing with a grapple skidder in conventional groundbased whole-tree (WT) harvesting. This method has greater potential to damage advance regeneration than those in which trees are processed at-stump. Hybrid tree-length (Hyb TL) harvesting using an stroke-boom delimber for in-woods processing might be a feasible alternative, but little is known about the production economics of this method. An experimental strip-cutting study was conducted in central Maine, US in the winter of 2018 to: (1) evaluate and compare operational productivity and costs of ground-based Hyb TL and WT methods; (2) identify factors influencing productivity of at-stump and at-landing log processing; and (3) calculate best management practice (BMP) implementation costs in WT harvesting. Time-motion data were recorded for operational phases such as felling, extraction, processing, sorting and loading; machine rates were calculated to determine productivity and costs of operations. Total cost of Hyb TL (US $17.01 m−3) was lower than that of WT ($18.38m−3). Processing costwas lower at-stump than at-landing ($2.66 and $2.73m−3 for Hyb TL and WT, respectively). This is likely due to fewer logs handled per cycle at-landing (1.2 logs per turn) compared to the number handled per cycle at-stump (1.4 logs per turn). Sensitivity analysis showed that a 30-m increase in average in-woods distance travelled by the delimber would result in a 41 per cent increase in the processing cost. Cost of BMP implementation in WT was $2.25 m−3 or $59.2 per productive machine hour. Results suggest that it is feasible to apply Hyb TL method in an industrial harvesting operation, though distance of in-woods delimber movement influences processing costs. Insights from this study will help forest managers and loggers efficiently plan and execute harvesting operations.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79894284","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}
Fast-growing tree species will be an important tool in the future production of renewables and in substituting non-renewable fossil energy sources. Sweden, like other countries around the Baltic Sea, has large areas of abandoned farmland usable for biomass production, but knowledge of growth performance of tree species candidates is insufficient. An experiment was initiated where six potentially high-producing tree species were compared. The best available plant material for each species was used on five sites over latitudes 56–64°N in Sweden. Results from the first 8–9 years are reported. Short rotation coppice willow (Salix schwerinii Wolf × S. viminalis L., clone ‘Tora’) had the fastest initial growth and production in southern Sweden. Hybrid aspen (Populus tremula L. × P. tremuloides Michx.) and poplar (Populus spp., section Tacamahaca), grown as short rotation forest, grew well over all sites and showed the highest productivity at the two northern sites. Hybrid larch (Larix ×eurolepis Henry) displayed a high potential at the two most southerly sites, whilst silver birch (Betula pendula Roth) was a medium-producing species at all sites. Norway spruce (Picea abies (L.) Karst.) started slowly, and Siberian larch (L. sukaczewii Dylis) produced poorly at the two northern sites in the initial stage. All tree species followed existing height development curves for the respective species on a high site quality level. Currently, well-growing clones of Populus spp. indicated that a wider selection of tree species can be used at high latitudes under climate change. The study showed a high growth potential for most species on former agricultural lands. However, measures to reduce climate and biological damage must be included in future efforts.
速生树种将成为未来可再生能源生产和替代不可再生化石能源的重要工具。与波罗的海沿岸的其他国家一样，瑞典有大片可用于生物质生产的废弃农田，但对候选树种的生长性能了解不足。开展了6种潜在高产树种的比较试验。在瑞典56-64°N纬度的5个地点使用了每个物种的最佳可用植物材料。报告前8-9年的结果。在瑞典南部地区，短轮生灌木柳(Salix schwerinii Wolf × S. viminalis L.，无性系‘Tora’)的初期生长和产量最快。杂交白杨(Populus tremula L. × P. tremuloides Michx.)和杨树(Populus spp.， section Tacamahaca)作为短轮作林生长，在所有样地均生长良好，其中北部两个样地的生产力最高。杂交落叶松(Larix ×eurolepis Henry)在两个最南端的样地表现出较高的产量潜力，而白桦(Betula pendula Roth)在所有样地都是中等产量。挪威云杉(Picea abies, L.)喀斯特)起步缓慢，西伯利亚落叶松(L. sukaczewii Dylis)在北部两个遗址的初始阶段产量较差。所有树种在高立地质量水平上遵循各自树种的现有高度发展曲线。目前，生长良好的杨树无性系表明，在气候变化的条件下，高纬度地区可以有更广泛的树种选择。研究表明，在原农业用地上，大多数物种具有较高的生长潜力。然而，减少气候和生物损害的措施必须纳入未来的努力。
{"title":"Early growth of different tree species on agricultural land along a latitudinal transect in Sweden","authors":"L. Rytter, Reimo Lutter","doi":"10.1093/forestry/cpz064","DOIUrl":"https://doi.org/10.1093/forestry/cpz064","url":null,"abstract":"\u0000 Fast-growing tree species will be an important tool in the future production of renewables and in substituting non-renewable fossil energy sources. Sweden, like other countries around the Baltic Sea, has large areas of abandoned farmland usable for biomass production, but knowledge of growth performance of tree species candidates is insufficient. An experiment was initiated where six potentially high-producing tree species were compared. The best available plant material for each species was used on five sites over latitudes 56–64°N in Sweden. Results from the first 8–9 years are reported. Short rotation coppice willow (Salix schwerinii Wolf × S. viminalis L., clone ‘Tora’) had the fastest initial growth and production in southern Sweden. Hybrid aspen (Populus tremula L. × P. tremuloides Michx.) and poplar (Populus spp., section Tacamahaca), grown as short rotation forest, grew well over all sites and showed the highest productivity at the two northern sites. Hybrid larch (Larix ×eurolepis Henry) displayed a high potential at the two most southerly sites, whilst silver birch (Betula pendula Roth) was a medium-producing species at all sites. Norway spruce (Picea abies (L.) Karst.) started slowly, and Siberian larch (L. sukaczewii Dylis) produced poorly at the two northern sites in the initial stage. All tree species followed existing height development curves for the respective species on a high site quality level. Currently, well-growing clones of Populus spp. indicated that a wider selection of tree species can be used at high latitudes under climate change. The study showed a high growth potential for most species on former agricultural lands. However, measures to reduce climate and biological damage must be included in future efforts.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83250938","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 : 2020-05-14DOI: 10.1093/forestry/cpaa006
M. Wulder, T. Hermosilla, G. Stinson, F. Gougeon, Joanne C. White, D. A. Hill, B. Smiley
Forests are dynamic ecosystems, subject to both natural and anthropogenic agents of change. Wildfire, harvesting and other human activities alter the tree-covered area present in forests. From national and international reporting perspectives, forests include areas currently treed, as well as those disturbed forest areas that are not currently treed but will be, given time for regeneration and the advancement of natural successional processes. As a consequence, forest area can be depicted at a particular point in time, informed by a retrospective temporal context. Using time series of Landsat imagery, annual land cover maps can be generated that are informed by knowledge of past disturbance history (such as wildfire and harvesting). In this research, we use over three decades of annual land cover data generated from Landsat time series to generate a spatially explicit estimate of the forest area of Canada in 2010. We demonstrate how land cover and disturbance information can be combined to map the area of ‘forest’, as defined by the Food and Agricultural Organization of the United Nations (FAO), within Canada’s 650 Mha of forested ecozones. Following this approach, we estimated Canada’s total forest area in 2010 to be 354.5 Mha. This estimate includes 324.5 Mha of current forest cover in 2010, plus an additional 33.2 Mha (or 9.4 per cent) of temporally informed forest area where tree cover had been temporarily lost due to fire or harvest, less 3.3 Mha that were removed to meet a definitional minimum size (0.5 ha) for contiguous forest area. Using Canada’s National Forest Inventory (NFI) as an independent reference source, the spatial agreement between the two estimates of forest area was ~84 per cent overall. Aspatially, the total area of the Landsat-derived estimate of 2010 forest area and the NFI baseline estimates differed by only 3 per cent, with notable regional differences in the wetland-dominated Hudson Plains Ecozone. Satellite-derived time series land cover and change information enable spatially explicit depictions of forest area (distinct from representations of forest cover) in a robust and transparent fashion, producing information of value to science, management and reporting information needs.
{"title":"Satellite-based time series land cover and change information to map forest area consistent with national and international reporting requirements","authors":"M. Wulder, T. Hermosilla, G. Stinson, F. Gougeon, Joanne C. White, D. A. Hill, B. Smiley","doi":"10.1093/forestry/cpaa006","DOIUrl":"https://doi.org/10.1093/forestry/cpaa006","url":null,"abstract":"\u0000 Forests are dynamic ecosystems, subject to both natural and anthropogenic agents of change. Wildfire, harvesting and other human activities alter the tree-covered area present in forests. From national and international reporting perspectives, forests include areas currently treed, as well as those disturbed forest areas that are not currently treed but will be, given time for regeneration and the advancement of natural successional processes. As a consequence, forest area can be depicted at a particular point in time, informed by a retrospective temporal context. Using time series of Landsat imagery, annual land cover maps can be generated that are informed by knowledge of past disturbance history (such as wildfire and harvesting). In this research, we use over three decades of annual land cover data generated from Landsat time series to generate a spatially explicit estimate of the forest area of Canada in 2010. We demonstrate how land cover and disturbance information can be combined to map the area of ‘forest’, as defined by the Food and Agricultural Organization of the United Nations (FAO), within Canada’s 650 Mha of forested ecozones. Following this approach, we estimated Canada’s total forest area in 2010 to be 354.5 Mha. This estimate includes 324.5 Mha of current forest cover in 2010, plus an additional 33.2 Mha (or 9.4 per cent) of temporally informed forest area where tree cover had been temporarily lost due to fire or harvest, less 3.3 Mha that were removed to meet a definitional minimum size (0.5 ha) for contiguous forest area. Using Canada’s National Forest Inventory (NFI) as an independent reference source, the spatial agreement between the two estimates of forest area was ~84 per cent overall. Aspatially, the total area of the Landsat-derived estimate of 2010 forest area and the NFI baseline estimates differed by only 3 per cent, with notable regional differences in the wetland-dominated Hudson Plains Ecozone. Satellite-derived time series land cover and change information enable spatially explicit depictions of forest area (distinct from representations of forest cover) in a robust and transparent fashion, producing information of value to science, management and reporting information needs.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75333103","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}
Xingtong Wu, M. Ruhsam, Y. Wen, P. Thomas, J. Worth, Xue-Ying Lin, Min-qiu Wang, Xinyu Li, Lu Chen, V. Lamxay, Nam Le Canh, G. Coffman
Glyptostrobus pensilis (Staunt.) Koch is a relict species in the Cupressaceae that previously had a global distribution but is now restricted to Southern China and two disjunct populations along the Annamite ranges in Laos and Vietnam. Using nuclear and chloroplast microsatellite markers (cpSSR and nSSR, respectively), we investigated the genetic diversity and divergence within and between 14 populations representing the entire range. Nuclear EST-SSR markers revealed low genetic diversity (He = 0.272) within populations and strong genetic differentiation (FST = 0.452) among populations. Populations in Laos, which represent the last primary forests of G. pensilis, contain the highest genetic diversity and are of particular conservation importance. The geographic cpSSR variation is consistent with the results from the nSSR analysis. Prolonged geographical isolation is likely to be the main reason for regional genetic patterns. Climatic changes during the Holocene, coupled with anthropogenic impacts, have further reduced its distribution and population size. The clear genetic structure suggests that at least, two refugia existed at different latitudes in Southeast Asia. Preserving and expanding its remaining habitat and increasing population sizes are likely to be the most important measures for the conservation of this species.
{"title":"The last primary forests of the Tertiary relict Glyptostrobus pensilis contain the highest genetic diversity","authors":"Xingtong Wu, M. Ruhsam, Y. Wen, P. Thomas, J. Worth, Xue-Ying Lin, Min-qiu Wang, Xinyu Li, Lu Chen, V. Lamxay, Nam Le Canh, G. Coffman","doi":"10.1093/forestry/cpz063","DOIUrl":"https://doi.org/10.1093/forestry/cpz063","url":null,"abstract":"Glyptostrobus pensilis (Staunt.) Koch is a relict species in the Cupressaceae that previously had a global distribution but is now restricted to Southern China and two disjunct populations along the Annamite ranges in Laos and Vietnam. Using nuclear and chloroplast microsatellite markers (cpSSR and nSSR, respectively), we investigated the genetic diversity and divergence within and between 14 populations representing the entire range. Nuclear EST-SSR markers revealed low genetic diversity (He = 0.272) within populations and strong genetic differentiation (FST = 0.452) among populations. Populations in Laos, which represent the last primary forests of G. pensilis, contain the highest genetic diversity and are of particular conservation importance. The geographic cpSSR variation is consistent with the results from the nSSR analysis. Prolonged geographical isolation is likely to be the main reason for regional genetic patterns. Climatic changes during the Holocene, coupled with anthropogenic impacts, have further reduced its distribution and population size. The clear genetic structure suggests that at least, two refugia existed at different latitudes in Southeast Asia. Preserving and expanding its remaining habitat and increasing population sizes are likely to be the most important measures for the conservation of this species.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87760570","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}
C. A. Marchioro, Karine Louise Santos, A. Siminski
The critically endangered Brazilian pine, also called araucaria, (Araucaria angustifolia (Bertol.) Kuntze) is a key species of the Araucaria moist forest (AMF, Mixed Ombrophilous Forest). Illegal timber extraction, agricultural conversion and severe degradation have reduced the AMF to only 13 per cent of its original cover, with climate change imposing additional challenges for cold adapted species such as araucaria. Previous studies have assessed climate change impacts on A. angustifolia, but have been limited by analysis constraints. Here, we used a machine learning technique to understand how land use and climate change might affect the distribution of A. angustifolia, and to evaluate the effectiveness of existing protected areas (PAs) to conserve this species. Our results demonstrated that despite the recent efforts to conserve the Atlantic Forest, conversion of natural habitats into forest plantation still occurs within araucaria’s distribution range. Our model predicted a drastic reduction in environmentally suitable areas for this species of up to 77 per cent in the coming decades. Also, the existing PAs show low efficacy to protect suitable areas in the future. Combined, these results suggest that A. angustifolia will be under great threat within the next few decades and the development of conservation strategies to save this species is essential. Ideally, the conservation programs should integrate in situ and on farm approaches, including forest management strategies. Although in situ strategies play an important role as gene banks, on-farm strategies can be used to promote the restoration and expansion of A. angustifolia populations in the areas predicted as suitable.
{"title":"Present and future of the critically endangered Araucaria angustifolia due to climate change and habitat loss","authors":"C. A. Marchioro, Karine Louise Santos, A. Siminski","doi":"10.1093/forestry/cpz066","DOIUrl":"https://doi.org/10.1093/forestry/cpz066","url":null,"abstract":"\u0000 The critically endangered Brazilian pine, also called araucaria, (Araucaria angustifolia (Bertol.) Kuntze) is a key species of the Araucaria moist forest (AMF, Mixed Ombrophilous Forest). Illegal timber extraction, agricultural conversion and severe degradation have reduced the AMF to only 13 per cent of its original cover, with climate change imposing additional challenges for cold adapted species such as araucaria. Previous studies have assessed climate change impacts on A. angustifolia, but have been limited by analysis constraints. Here, we used a machine learning technique to understand how land use and climate change might affect the distribution of A. angustifolia, and to evaluate the effectiveness of existing protected areas (PAs) to conserve this species. Our results demonstrated that despite the recent efforts to conserve the Atlantic Forest, conversion of natural habitats into forest plantation still occurs within araucaria’s distribution range. Our model predicted a drastic reduction in environmentally suitable areas for this species of up to 77 per cent in the coming decades. Also, the existing PAs show low efficacy to protect suitable areas in the future. Combined, these results suggest that A. angustifolia will be under great threat within the next few decades and the development of conservation strategies to save this species is essential. Ideally, the conservation programs should integrate in situ and on farm approaches, including forest management strategies. Although in situ strategies play an important role as gene banks, on-farm strategies can be used to promote the restoration and expansion of A. angustifolia populations in the areas predicted as suitable.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90618855","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}
S. Huuskonen, Soili Haikarainen, Tiina Sauvula-Seppälä, H. Salminen, M. Lehtonen, J. Siipilehto, A. Ahtikoski, K. Korhonen, J. Hynynen
We evaluated the impacts of juvenile stand management on wood production based on a nationwide scenario analysis. Measured plot-level information of the Finnish 11th National Forest Inventory (NFI) from juvenile stands formed the initial data for the analysis. To represent a total of 2.5 million hectares of productive forest land available for wood production, 6900 sample plots were selected. We predicted the development of the sample-plot stands for the next 100 years using the Motti stand simulator. We examined the impacts of juvenile stand management, including early cleaning and precommercial thinning, with three scenarios of different intensities of early-stage management (intensive, no management and business-as-usual). The results showed the benefits of juvenile stand management: earlier harvesting revenues, larger total removals, more valuable wood in the removals, and additional benefits that are associated with the first commercial thinning (i.e. no need for clearing before thinning, a larger stem size of removed trees). The main downside of juvenile stand management was the cost of the early cleaning and precommercial thinning. According to the results, a €560 million increase in costs would result in a €1700 million increase in stumpage earnings in Finnish forests during the next 100-year period. The 34 million m3 increase in the sawlog yield together with 28 million m3 decrease in the pulpwood yield also demonstrated the nationwide potential for increasing valuable sawlog production by intensive management of juvenile stands.
{"title":"Benefits of juvenile stand management in Finland—impacts on wood production based on scenario analysis","authors":"S. Huuskonen, Soili Haikarainen, Tiina Sauvula-Seppälä, H. Salminen, M. Lehtonen, J. Siipilehto, A. Ahtikoski, K. Korhonen, J. Hynynen","doi":"10.1093/forestry/cpz075","DOIUrl":"https://doi.org/10.1093/forestry/cpz075","url":null,"abstract":"\u0000 We evaluated the impacts of juvenile stand management on wood production based on a nationwide scenario analysis. Measured plot-level information of the Finnish 11th National Forest Inventory (NFI) from juvenile stands formed the initial data for the analysis. To represent a total of 2.5 million hectares of productive forest land available for wood production, 6900 sample plots were selected. We predicted the development of the sample-plot stands for the next 100 years using the Motti stand simulator. We examined the impacts of juvenile stand management, including early cleaning and precommercial thinning, with three scenarios of different intensities of early-stage management (intensive, no management and business-as-usual). The results showed the benefits of juvenile stand management: earlier harvesting revenues, larger total removals, more valuable wood in the removals, and additional benefits that are associated with the first commercial thinning (i.e. no need for clearing before thinning, a larger stem size of removed trees). The main downside of juvenile stand management was the cost of the early cleaning and precommercial thinning. According to the results, a €560 million increase in costs would result in a €1700 million increase in stumpage earnings in Finnish forests during the next 100-year period. The 34 million m3 increase in the sawlog yield together with 28 million m3 decrease in the pulpwood yield also demonstrated the nationwide potential for increasing valuable sawlog production by intensive management of juvenile stands.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85171896","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}
H. Evans, D. Williams, G. Hoch, A. Loomans, M. Marzano
The threats posed by the buprestid beetles emerald ash borer (Agrilus planipennis Fairmaire) and bronze birch borer (Agrilus anxius Gory) have been the subject of considerable research, primarily to develop methods for detection and management of the pests. PREPSYS, a Euphresco project, has worked with collaborators globally to assess the ‘state of the art’ for the two insect pests and to identify those measures that would best prepare Europe for potential invasion by the pests, especially emerald ash borer which is now in the western part of Russia and in eastern Ukraine. Building on an excellent exchange of knowledge and discussion at the OECD-sponsored international conference held in Vienna in October 2018, the concept of a European Toolbox to increase preparedness for dealing with the pests has been developed. This includes key components including surveillance, direct intervention, use of natural enemies and increased awareness of the problems associated with the pests. Collaboration is essential in delivering and refining the European Toolbox.
{"title":"Developing a European Toolbox to manage potential invasion by emerald ash borer (Agrilus planipennis) and bronze birch borer (Agrilus anxius), important pests of ash and birch","authors":"H. Evans, D. Williams, G. Hoch, A. Loomans, M. Marzano","doi":"10.1093/forestry/cpz074","DOIUrl":"https://doi.org/10.1093/forestry/cpz074","url":null,"abstract":"\u0000 The threats posed by the buprestid beetles emerald ash borer (Agrilus planipennis Fairmaire) and bronze birch borer (Agrilus anxius Gory) have been the subject of considerable research, primarily to develop methods for detection and management of the pests. PREPSYS, a Euphresco project, has worked with collaborators globally to assess the ‘state of the art’ for the two insect pests and to identify those measures that would best prepare Europe for potential invasion by the pests, especially emerald ash borer which is now in the western part of Russia and in eastern Ukraine. Building on an excellent exchange of knowledge and discussion at the OECD-sponsored international conference held in Vienna in October 2018, the concept of a European Toolbox to increase preparedness for dealing with the pests has been developed. This includes key components including surveillance, direct intervention, use of natural enemies and increased awareness of the problems associated with the pests. Collaboration is essential in delivering and refining the European Toolbox.","PeriodicalId":12342,"journal":{"name":"Forestry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2020-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79699426","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}
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