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CPSDv0: a forest stand structure database for plantation forests in China

Big Earth Data 2023年第1期7卷 212-230页

作者： Xiuchen Wu Xiaofei Jiang Hongyan Liu Craig Allen Xiaoyan Li Pei Wang Zongshan Li Yuting Yang Shulei Zhang Fangzhong Shi Jiaojun Zhu Pengtao Yu Mei Zhou Pengwu Zhao Yanhui Wang Chao Yue Deliang Chen State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingChina School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes Peking UniversityBeijingChina U.S.Geological Survey-Nebraska Cooperative Fish&Wildlife Research Unit School of Natural Resources423 Hardin HallUniversity of NebraskaLincolnNEUSA State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijingChina CAS Key Laboratory of Forest Ecology and Management Qingyuan Forest CERNInstitute of Applied EcologyChinese Academy of SciencesShenyangChina Key Laboratory of Forest Ecology and Environment of the National Forestry and Grassland Administration of China Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of ForestryBeijingChina Academy of Forestry Inner Mongolia Agricultural UniversityHuhhotChina State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYanglingShaanxiChina Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburgSweden

Forest stand structure is not only a crucial factor for regulating forest functioning but also an important indicator for sustainable forest management and ecosystem *** there exists a few national/global structure databases for natural forests,a country-wide synthetic structure database for plantation forests over China,the world’s largest player in plantation forests,has not been *** this study,we built a country-wide synthetic stand structure database by surveying more than 600 peer-reviewed *** database covers tree species,mean stand age,mean tree height,stand density,canopy coverage,diameter at breast height,as well as the associated ancillary in-situ topographical and soil properties.A total of 594 pub-lished studies concerning diverse forest stand structure parameters were compiled for 46 tree *** first synthesis for stand structure of plantation forests over China supports studies on the evolution/health of plantation forests in response to rapid climate change and intensified disturbances,and benefits country-wide sustainable forest management,future afforestation or reforestation *** users include those studying forest community dynamics,regional tree growth,ecosystem stability,and health,as well as those working with conservation and sustainable *** dataset is freely acces-sible at http://***/10.11922/sciencedb.j00076.00091.

关键词： stand structure plantation tree age tree height stand density canopy coverage

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stand structure and height-diameter relationship of a degraded Populus euphratica forest in the lower reaches of the Tarim River, Northwest China

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Journal of Arid Land 2015年第4期7卷 544-554页

作者： AISHAN Tayierjiang HALIK ümüt Florian BETZ TIYIP Tashpolat DING Jianli NUERMAIMAITI Yiliyasijiang Key Laboratory of Oasis Ecology College of Resource & Environmental Sciences Xinjiang University Faculty of Geography and Mathematics Catholic University of Eichstaett-Ingolstadt

Understanding stand structure and height-diameter relationship of trees provides very useful information to establish appropriate countermeasures for sustainable management of endangered forests. Populus euphratica, a dominant tree species along the Tarim River watershed, plays an irreplaceable role in the sustainable development of regional ecology, economy and society. However, as the result of climate changes and human activities, the natural riparian ecosystems within the whole river basin were degraded enormously, particularly in the lower reaches of the river where about 320 km of the riparian forests were either highly degraded or dead. In this study, we presented one of the main criteria for the assessment of vitality of P. euphrafica forests by estimating the defoliation level, and analyzed forest structure and determined the height-diameter （height means the height of a tree and diameter means the diameter at breast height （DBH） of a tree） relationship of trees in different vitality classes （i.e. healthy, good, medium, senesced, dying, dead and fallen）. Trees classified as healthy and good ac- counted for approximately 40% of all sample trees, while slightly and highly degraded trees took up nearly 60% of total sample trees. The values of TH （tree height） and DBH ranged from 0-19 m and 0-125 cm, respectively. Trees more than 15 m in TH and 60 cm in DBH appeared sporadically. Trees in different vitality classes had different distribution patterns. Healthy trees were mainly composed more of relatively younger trees than of degraded tress. The height-diameter relationships differed greatly among tress in different vitality classes, with the coefficients ranging from 0.1653 to 0.6942. Correlation coefficients of TH and DBH in healthy and good trees were higher than those in trees of other vitality classes. The correlation between TH and DBH decreased with the decline of tree vitality. Our results suggested that it might be able to differentiate degraded P. eup

关键词： stand structure height-diameter relationship Populus euphratica tree vitality Tarim River

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Floristic Diversity and stand structure of the Ngambe-Ndom-Nyanon Communal Forest, Littoral Region of Cameroon

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Open Journal of Forestry 2022年第4期12卷 503-520页

作者： Ervis Dongmo Manfothang Precilia Tumenta Steve Nanfack Tassiamba Vianny Rodel Nguimdo Kelvin Yenkong Defouh Department of Forestry Faculty of Agronomy and Agricultural Sciences University of Dschang Dschang Cameroon Ebo Forest Research Project Douala Cameroun

The present study aimed to contribute to the sustainable management of the Ngambe-Ndom-Nyanon communal forest in Cameroon. Thus, an evaluation of the floristic diversity and stand structure of the forest was carried out. By using systematic sampling, a diverse inventory of the plant species was carried out, taking into account the dendrometric measurements of all the species present in the forest (trees, shrubs, herbs). Data were analyzed with Microsoft Excel software to bring out curves and histograms. This software also made it possible to produce tables and also to come up with different diversity indexes. A total of 19,007 individuals from 395 plant species grouped into 99 families were identified in the area. The family Euphorbiaceae was the most represented. Species dominated in this stand were Uapaca guineensis and Pycnanthus angolensis with 9% and 6% of individuals identified. The result of the Shannon index showed that all the strata in the forest are diversified with the highest values in the adult secondary forest (FSA) with indices of 4.74, followed by young secondary forest (FSJ) and the secondary forest (FS) with indice respectively 4.68 and 4.61. The values of the Sorensen index show that 100% of species are common in the young secondary forest (FSJ) and the adult secondary forest (FSA). In the same forest, the FSA and Swamp with FSJ and Swamp have just 15% of species in common respectively. This diversified forest stand projects an inverted J structure, thus testifying to its strong potential for stems of the future. According to the research objectives, some measures were proposed for sustainable management of this forest, such as the reforestation of areas degraded by agricultural activities and the promotion of agroforestry practices by using trees with the high fertilizing potential to improve agricultural yields while preserving the trees in place.

关键词： Floristic Diversity stand structure Floristic Index Dendrometric

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How does the stand structure of treeline-forming species shape the treeline ecotone in different regions of the Nepal Himalayas?

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Journal of Mountain Science 2020年第10期17卷 2354-2368页

作者： Parveen K.CHHETRI Raju BISTA Krishna B.SHRESTHA Department of Earth Science and Geography California State UniversityDominguez HillsCarsonCalifornia90747USA Department of Biological Sciences University of BergenPO Box 7803N-5020BergenNorway

stand structure dynamics are considered as major happenings in any forest as a response to environmental ***,this important topic is underrepresented in the treeline studies in the Nepal *** aimed to investigate site-as well as species-specific changes in morphometric features(basal diameter,crown cover,density,and height)along the elevational gradient across treeline ecotones in response to recent environmental *** stand structure characteristics of Abies spectabilis,Pinus wallichiana,and Betula utilis across the treeline ecotone of three study sites in Eastern(Barun),Central(Manang),and Western(Dhorpatan)Nepal were analyzed to elucidate structural ***,eight transects(20 m×(60–250 m))across the treeline ecotone were *** of all life forms,trees(>2 m),saplings(0.5–2 m),and seedlings(stand structure dynamics were *** rate of basal area increment was higher in Barun,but the Manang treeline,despite profound regeneration in recent years,had a low annual basal area ***,the altitudinal distribution of age and morphometry were not consistent among those ***,intra-specific competition was not *** site-specific stand structure dynamics explain why treelines do not respond uniformly to increasing *** invokes,in further studies,the incorporation of the tree’s morphometric adaptation traits,phenotypic plasticity,and interactions between species genotype and the environment.

关键词： Climate change Morphometry Nepal Himalayas stand structure Treeline Tree-rings

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Exploring tree diversity and stand structure of savanna woodlands in southeastern Sudan

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Journal of Arid Land 2020年第4期12卷 609-617页

作者： Ahmed M M HASOBA Ahmed A H SIDDIG Yousif E YAGOUB Faculty of Forest Sciences and Technology University of GeziraMadani 22212Sudan Faculty of Forestry University of KhartoumKhartoum North 13314Sudan Department of Environmental Conservation University of Massachusetts AmherstAmherst 01003USA

Savanna woodlands in Sudan host great biodiversity, provide a plethora of ecosystem goods and services to local communities, and sustain numerous ecological functions. Although the importance of the Acacia trees in these areas is well known, up-to-date information about these woodlands' diversity is limited and changes in their woody vegetation composition, density, diversity and relative frequency are not monitored over time. This study explored tree diversity and stand stage structure in Nuara Reserved Forest, a typical savanna woodland ecosystem in southeastern Sudan. A total of 638 circular sample plots(1000 m^2 for each) were established using a systematic sampling grid method. The distance between plots was 200 m. In each plot, all living trees with diameter at breast height(DBH) ≥5.00 cm were identified and counted, and their DBH values were recorded. From these data, tree composition, diversity, density and stage structure were assessed. There were 12,259 individual trees representing four species(Acacia seyal, Balanites aegyptiaca, Acacia Senegal and Acacia mellifera) that belong to two families. The dominant species was Acacia seyal. Average tree density was 191 trees/hm^2 and the Shannon-Weiner index for trees diversity was 0.204. Overall, young trees comprised 86.30% of the forest. The state of tree richness and density in the study area was low compared to other similar environments in the region and around the world. We recommended adoption of a proper management system that includes monitoring of woody vegetation diversity in this forest, and management actions to enhance tree diversity and sustain ecosystem services to local communities. In addition to care for the dominant Acacia seyal stands, more attention and conservation should be devoted to reestablishing Acacia senegal and Acacia mellifera trees because of their high ecological and economic values for local communities.

关键词： species diversity stand structure savanna woodland ecosystem forest monitoring forest management ecosystem services Nuara Reserved Forest

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STUDY ON THE TREE GROWTH, ARCHITECTURE AND stand structure OF KOREAN PINE PLANTATION

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Journal of Northeast Forestry University 1995年第3期6卷 84-88页

作者：葛剑平李传荣李平李景文 Northeast Forestry University P.R. China

The artificial pure and mixed Korean pine (Pinus koraiensis) forests were investigated at Dailing Forestry Bureau in Xiaoxing'an mountains from 1990 to 1992. Depending on the distance between the samplings of Korean pine and their neighbor trees, the neighbor tree height, the size of neighbor tree canopy, and dimension of neighbor tree. The forest structure was classified into three types: (1) prowth of a tree in the light (open), (2) Growth of a tree in the canopy gap (Gap), (3)Growth of a tree under broad-leaved tree canopy. The frequeney, height, and age of stem divergence of Korean pine tree were investigated by sampling trees. The temporal and spatial model of the tree growth was applied on basis of the height of stem divergence, ratio of height and DBH, and character of tree *** morphology and growth character of Korean pine trees during different development stage were forecasted.

关键词： Korean pine plantation Tree growth model stand structure

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Impact of cattle density on the structure and natural regeneration of a turkey oak stand on an agrosilvopastoral farm in central Italy

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Journal of Forestry Research 2024年第1期35卷 168-182页

作者： Alessandra Pacini Francesco Pelleri Francesco Marini Alberto Maltoni Barbara Mariotti Gianluigi Mazza Maria Chiara Manetti Department of Agriculture FoodEnvironmentand ForestryUniversity of Florence50144 FlorenceItaly CREA Research Centre for Forestry and Wood 52100 ArezzoItaly PEFC Programme for the Endorsement of Forest Certification 06135 PerugiaItaly

On an agrosilvopastoral farm in central Italy where Maremmana cattle graze in Turkey oak forests,we evaluated the impact of different livestock densities on stand structure,tree diversity and natural regeneration in four types of grazed areas based on the grazing regime adopted:calf-grazed,high-intensity-grazed,low-intensity-grazed,ungrazed *** each area,we set up three permanent circular plots(radius of 15 m)to survey the structural and dasometric characteristics of the overstorey,understorey,and regeneration *** results showed that grazing negatively affected the complexity of the forest structure and its potential to regenerate and maintain a high level of *** differences in stand structure observed between the grazing areas were closely related to livestock *** most sensitive components of the system were the understorey and the regeneration ***,the current grazing management did not affect the dominant tree structure or its *** findings identified medium-term monitoring and regeneration management as the two significant aspects to consider when assessing sustainable *** forests can be established by excluding graz-ing for about 20–25 years.

关键词： Agroforestry stand structure Regeneration Tree biodiversity Grazing intensity

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What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships

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Forest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang John A.Kershaw Mark J.Ducey Yuan Sun James B.McCarter Integrated Forest Mensuration and Systems Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA College of Forestry Nanjing Forestry UniversityNanjing210037China Scientific Programmer RayonierYuleeFLUSA

Volume is an important attribute used in many forest management *** from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume *** density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height *** density was not included(Volume=f(Diameter,Height)),the opposite was *** models with density included,moment-based estimators of stand diameter and height performed better than all other *** models without density,largest tree estimators of stand diameter and height performed better than other *** overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses.

关键词： Allometric relationships stand structure Volume estimation stand-level attributes

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Prediction of tree crown width in natural mixed forests using deep learning algorithm

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Forest Ecosystems 2023年第3期10卷 287-297页

作者： Yangping Qin Biyun Wu Xiangdong Lei Linyan Feng Key Laboratory of Forest Management and Growth Modelling National Forestry and Grassland AdministrationInstitute of Forest Resource Information TechniquesChinese Academy of ForestryBeijing100091China Southwest Survey and Planning Institute National Forestry and Grassland AdministrationKunming650031China

Crown width(CW)is one of the most important tree metrics,but obtaining CW data is laborious and timeconsuming,particularly in natural *** Deep Learning(DL)algorithm has been proposed as an alternative to traditional regression,but its performance in predicting CW in natural mixed forests is *** aims of this study were to develop DL models for predicting tree CW of natural spruce-fir-broadleaf mixed forests in northeastern China,to analyse the contribution of tree size,tree species,site quality,stand structure,and competition to tree CW prediction,and to compare DL models with nonlinear mixed effects(NLME)models for their *** amount of total 10,086 individual trees in 192 subplots were employed in this *** results indicated that all deep neural network(DNN)models were free of overfitting and statistically stable within 10-fold cross-validation,and the best DNN model could explain 69%of the CW variation with no significant *** addition to diameter at breast height,stand structure,tree species,and competition showed significant effects on *** NLME model(R^(2)=0.63)outperformed the DNN model(R^(2)=0.54)in predicting CW when the six input variables were consistent,but the results were the opposite when the DNN model(R^(2)=0.69)included all 22 input *** results demonstrated the great potential of DL in tree CW prediction.

关键词： Mixed forests Deep neural networks Crown width stand structure Competition

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Plant functional trait diversity and structural diversity co-underpin ecosystem multifunctionality in subtropical forests

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Forest Ecosystems 2023年第2期10卷 153-161页

作者： Shuai Ouyang Mengmeng Gou Pifeng Lei Yue Liu Liang Chen Xiangwen Deng Zhonghui Zhao Yelin Zeng Yanting Hu Changhui Peng Wenhua Xiang Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha410004China Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province Huitong438107China Ecology and Nature Conservation Institute Chinese Academy of ForestryBeijing100101China Institute of Environment Sciences Department of Biological SciencesUniversity of Quebec at MontrealMontrealQCH3C 3P8Canada

Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem ***,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains *** this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical *** community-weighted mean of tree maximum height was the best predictor of ecosystem *** diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal *** structure-played an important role in modulating the effects of tree diversity on *** work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.

关键词： Abiotic and biotic factors Biodiversity Functional composition Functional traits Soil microbial diversity stand structure

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