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Analysis of General Status and Examination of Estimation Errors for One-Variable Tree Volume Tables in China ZENG Weisheng, YANG Xueyun FOREST RESOURCES WANAGEMENT    2023, 0 (2): 43-49.   DOI: 10.13466/j.cnki.lyzygl.2023.02.006 Abstract （395）   HTML （20）    PDF （1271KB）（1341）       Knowledge map    Save Tree volume tables are important basic tools in forest inventory and monitoring.One-variable tree volume tables have been used in continuous forest inventories (CFIs) of China for more than 40 years,but we have never systematically tested the applicability in nowadays.In this paper,the general status of currently used one-variable tree volume tables were analyzed from the aspects of quantity,zoning,tree species,and model type;and most of one-variable tree volume tables were examined by using the tree height data of 138 911 sample trees.The results showed that the total number of one-variable tree volume tables used in China's CFI reached 707,and the number of provincial volume tables varied greatly,from 3 to 171;there were 18 provincial regions divided into several modeling populations,while others were based on whole provincial regions;there were also great differences in the number of tree species groups for developing tree volume tables in each provincial region,with the least being 3 and the most being 31;a total of 25 models were used to develop tree volume tables,but nearly 90% of the tree volume tables were based on 5 models;about 70% of the one-variable tree volume tables exceeded the allowable error limit of ±5%,and 10 of 31 provincial regions and four forest industry groups exceeded the range of ±10% of the volume estimation errors,among which the maximum negative bias was -14.86% and the maximum positive bias was 23.22%.Based on the results of analysis,it is suggested that at the end of this inventory,a comprehensive and systematic applicability test should be carried out on the current one-variable tree volume tables;and unified revision should be made on the tree volume tables with significant deviation,so as to optimize and adjust the division of modeling populations,tree species grouping and the volume model type;and the change of volume estimation method from one-variable table to two-variable table should be actively promoted. Table and Figures | Reference | Related Articles | Metrics

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Key Data Results and Trend Analysis of the Sixth National Survey on Desertification and Sandification ZAN Guosheng, WANG Cuiping, LI Feng, LIU Zheng, SUN Tao FOREST RESOURCES WANAGEMENT    2023, 0 (1): 1-7.   DOI: 10.13466/j.cnki.lyzygl.2023.01.001 Abstract （3097）   HTML （266）    PDF （1091KB）（1335）       Knowledge map    Save The Sixth National Survey on Desertification and Sandification was based on the results of the Third National Land Survey,using 2019 as the benchmark year.The results showed a comprehensive status of desertification and sandification in China.This paper presented a brief overview of this survey,the status and dynamic changes of desertification and sandification in China,conducted a comprehensive analysis of the current situation,and proposed some suggestions for combating desertification and sandification.The survey results showed that,until 2019,the desertification land area in China was 257.371 3 million hm2 and the sandification land area was 168.782 3 million hm2.Compared with 2014,the desertification area of China decreased by 3.788 0 million hm2 with an average annual decrease of 757.6 thousand hm2.The sandification area of China decreased by 3.335 2 million hm2 with an average annual net reduction of 667 thousand hm2. Table and Figures | Reference | Related Articles | Metrics

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Main Results of the Fourth Rocky Desertification Survey in Karst Area and Analysis of Rocky Desertification Control Situation NING Xiaobin, WU Xiebao, HUANG Junwei, WU Houjian, LIU Wei, PENG Xi FOREST RESOURCES WANAGEMENT    2023, 0 (3): 9-14.   DOI: 10.13466/j.cnki.lyzygl.2023.03.002 Abstract （413）   HTML （31）    PDF （972KB）（911）       Knowledge map    Save The fourth rocky desertification survey in Karst area was based on the result of the third national land survey,while taking 2021 as the base year to comprehensively investigate the condition and change of the rocky desertification land China.This paper briefly introduced the basic situation of the fourth rocky desertification survey,the present situation and dynamic change of rocky desertification land,as well as analyzed the current situation of rocky desertification control,and put forward countermeasures and suggestions.The results showed that,the rocky desertification land area was 7.223 million hm2 by 2021.Compared with 2016,the net decrease of rocky desertification land area was 3.331 million hm2,while the average annual decrease was 0.666 million hm2.The main results indicating that the rocky desertification land in China presents the overall evolution direction of "area decreasing,degree reduction and ecological condition being stable ". Table and Figures | Reference | Related Articles | Metrics

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Habitat Characteristics and Effects on Growth of Arundinaria faberi in Different Slope Positions of Subalpine Meadow YAN Keyu, CHEN Pingping, LI Jianxing, ZHANG Limei, LIU Hui, CHEN Zhengfa FOREST RESOURCES WANAGEMENT    2023, 0 (2): 70-78.   DOI: 10.13466/j.cnki.lyzygl.2023.02.010 Abstract （198）   HTML （7）    PDF （2297KB）（646）       Knowledge map    Save As a dominant plant species in subalpine meadows on the low-latitude plateau,it is of great guiding significance to clarify the habitat characteristics and key growth factors of different slope positions of Arundinaria faberi for its community protection.The research object was Arundinaria faberi in the subalpine meadow of Gaoben Mountain in Xundian,Yunnan.By investigating the characteristics of growth and habitat factors of Arundinaria faberi in different slope positions,the key growth factors of Arundinaria faberi were identified by correlation heat map.The results showed that:1) The air temperature and relative humidity tended to decrease with the increase of the slope position,while the wind speed and solar radiation intensity increased with the increase of the slope position.2) The soil particle composition of different slope positions was mainly composed of silt particles.The soil bulk density increased with the increase of the slope position.The soil moisture content,large aggregate content and soil chemical indicators all increased first and then decreased with the increase of the slope position.The meadow soil was obviously acidic,and the soil quality level reflected by the physical and chemical characteristics of the middle slope soil was relatively higher.3) With the increase of the slope position,the morphology and community characteristics of Arundinaria faberi showed a significant deterioration trend.4) Correlation heat map analysis showed that air temperature,solar radiation intensity,wind speed,soil bulk density and available phosphorus had a great influence on the corresponding growth characteristics of Arundinaria faberi among which air temperature,solar radiation intensity,wind speed and soil bulk density were the most influential key factor for growth. Table and Figures | Reference | Related Articles | Metrics

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Discussion on the Technical System of Forest Fire Risk Assessment JIANG Chunying, YANG Xueqing, ZHANG Guoli, SUN Zhichao, JIANG Yun'an, JIANG Aijun FOREST RESOURCES WANAGEMENT    2023, 0 (2): 17-26.   DOI: 10.13466/j.cnki.lyzygl.2023.02.003 Abstract （394）   HTML （20）    PDF （1228KB）（612）       Knowledge map    Save The risk assessment index system of forest fire was constructed by comprehensively utilizing the hazard of forest fire,the exposure and vulnerability of disaster bodies.The hazard of disaster was based on the contents of combustibles,meteorological conditions,field fire sources,terrain and topography,the exposure of disaster bodies was based on the contents of above-ground living biomass,number of buildings,population,GDP,and the vulnerability of disaster bodies was based on the proportion of flammable forest land,proportion of combustible building area,proportion of the elderly and young population,vulnerability of economic activities.Using The Analytic Hierarchy Process and expert scoring,this paper determined the weights of each evaluation indicator.It refined the accuracy of forest fire risk assessment to multiple spatial scales such as small class,30 arc second geographic grid,township level,county level,etc.to meet the accuracy requirements of forest fire prevention management at different administrative levels of the country,province,city,and county.At the same time,this paper proposed the best solution for forest fire risk identification in different regions and periods. Table and Figures | Reference | Related Articles | Metrics

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Species Diversity and Its Associated Factors of Castanopsis orthacantha Community in Central Yunnan PENG Zexi, LUO Hang, LI Xiaoying, XU Yanhong, YIN Wuyuan, ZHU Hongqin, CHEN Yuqiang, CHEN Xiaoqin FOREST RESOURCES WANAGEMENT    2023, 0 (2): 138-146.   DOI: 10.13466/j.cnki.lyzygl.2023.02.019 Abstract （240）   HTML （9）    PDF （1023KB）（567）       Knowledge map    Save In order to accurately grasp the species diversity level of Castanopsis orthacantha community and its relationship with related factors in central Yunnan,based on the investigation of typical plots,the Margalef richness index,Pielou evenness index,Shannon-Weiner diversity index and species diversity comprehensive index were used to measure the species diversity level of Castanopsis orthacantha community,and the grey correlation analysis method was used to explore the relationship between species diversity level and site factors,stand factors and forest disturbance intensity.The results showed that:1) The species composition of Castanopsis orthacantha community was rich,involving 75 families,141 genera and 202 species,and the species composition of shrub layer was the most complex.The tree species composition of the arbor layer had the characteristics of typical subtropical evergreen broad-leaved forest.And there were significant differences in species composition and important values in different regions.2) The richness index,diversity index and evenness index of shrub layer (including regeneration layer) were the highest,and the species diversity of Castanopsis orthacantha community was at a medium level.The species diversity of different survey areas in the study area was different.The contribution rate of herb layer and shrub layer (including regeneration layer) to the comprehensive index of community species diversity was the highest.3) There was a strong correlation between species diversity and six factors in three levels of site factors,stand factors and forest disturbance intensity.The order of correlation degree was altitude>forest disturbance intensity>average DBH>aspect>plant density>slope.Through research,the aim is to provide a basis for the restoration and conservation measures of Castanopsis orthacantha community in central Yunnan. Table and Figures | Reference | Related Articles | Metrics

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Research on Carbon Peak and Carbon Sink Capacity of Major Carbon Emitting Countries in the World ZHANG Zhe, ZHANG Yuxing FOREST RESOURCES WANAGEMENT    2023, 0 (2): 1-9.   DOI: 10.13466/j.cnki.lyzygl.2023.02.001 Abstract （347）   HTML （29）    PDF （4802KB）（496）       Knowledge map    Save At the level of realistic economy and technology,we must first achieve carbon peaking in order to achieve carbon neutrality.Studying the carbon peak foundation and carbon sink capacity of the major carbon emitting countries in the world has important reference significance for China to achieve carbon peak and carbon neutrality.This study sorted out the top 24 countries in economic aggregate among the world's 224 countries and regions.Based on the data of CO2 emissions,total GDP,energy consumption and reserves on forest carbon sink from 1960 to 2018,it found out total GDP and GDP per capita were positively correlated with CO2 emissions before carbon peak.When GDP per capita reached $\$$20000 to $\$$35000,and low-carbon energy accounted for more than 35%,it would be possible to achieve carbon peak and reduce carbon emissions.In addition,when GDP per capita reached $\$$35000 to $\$$45000,and high-carbon energy (coal and oil) accounted for no more than 55%,it would also be possible to achieve carbon peak and reduce carbon emissions.Energy supply structure was the first determinant of carbon peak time.The results showed that if the proportion of low-carbon energy was higher,it was easier to achieve carbon peak.Nowadays,the forest carbon sink capacity of 24 countries was constantly improving.However,the reserves on forest carbon sink were less than 15% of the country's annual carbon emissions in most countries.It still takes a long time to achieve carbon neutrality.Therefore,special attention should be paid to the healthy,stable,efficient and sustainable management of forest ecosystems. Table and Figures | Reference | Related Articles | Metrics

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The Resource Status and Conservation Strategies of National Key Protected Wild Plants in China JIANG Yafang, TIAN Jing, LIU Zengli, MA Wei, SHAO Wei, BAI Ling FOREST RESOURCES WANAGEMENT    2023, 0 (4): 1-10.   DOI: 10.13466/j.cnki.lyzygl.2023.04.001 Abstract （465）   HTML （53）    PDF （1248KB）（483）       Knowledge map    Save Accurate data on the population and survival status of wild plant are the basis for the plant diversity conservation.The Regulations of the People's Republic of China on the Protection of Wild Plants make it clear that the wild plants administrative departments should periodically organize surveys of national key protected wild plants,and establish wild plants resource archives.Therefore,China launched the second national survey of national key protected wild plants in 2012.Based on the survey data,the population,community area and in situ conservation status of 283 species of national key protected wild plants in China are reported.Reasons for the changes of wild plant resources over the past 10 years are also discussed through comparative analysis between the first and second national survey of national key protected wild plants.In order to advance conservation and management of wild plants in China,several countermeasures and suggestions were put forward,including establishing a national platform for wild plant supervision and management,improving the plant diversity conservation system,and carrying out the wild plant rescue and conservation projects. Table and Figures | Reference | Related Articles | Metrics

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Analysis of Vegetation Cover Changes in Beijing from 2005 to 2020 YU Shiyong, XU Qian, YU Xiaofei FOREST RESOURCES WANAGEMENT    2023, 0 (3): 98-104.   DOI: 10.13466/j.cnki.lyzygl.2023.03.013 Abstract （329）   HTML （13）    PDF （3716KB）（404）       Knowledge map    Save Based on NDVI data from 2005—2020,the spatial distribution characteristics,temporal distribution characteristics and spatio-temporal characteristics of vegetation were analysed using NDVI classification and difference analysis to reveal the spatio-temporal patterns of NDVI changes in Beijing,and to explore the reasons for the changes by analysing the vegetation cover changes in Beijing in the past 15 years.Through analysis,it is found that,the overall vegetation cover in the Beijing area is at a high level.From a regional perspective,the areas with very high NDVI mean coverage classes in Beijing from 2005 to 2020 were all located in the Jundu and Xishan mountain ranges.The vegetation coverage of Mentougou District,Huairou District,Yanqing District,Fangshan District,Changping District and Pinggu District was at the highest level in Beijing.In terms of time,the level of vegetation coverage changed significantly from 2005 to 2020,with the average annual NDVI value increasing from 0.659 0 to 0.756 6,an increase of 14.81%.The proportion of area with "very high" vegetation coverage increased from 5.31% to 47.79%,and the proportion of area with "low" vegetation coverage decreased from 5.91% to 1.25%.In terms of spatiotemporal change characteristics of vegetation,the area with obvious improvement and slight improvement accounted for more than 80%.Two "million mu afforestation" projects and mountain forest management were the main driving forces to improve the quality of vegetation coverage in Beijing. Table and Figures | Reference | Related Articles | Metrics

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Dynamic Monitoring of Spartina alterniflora in Xiangshan Harbor Based on GEE and Random Forest LIANG Licheng, FU Xiaoqiang, ZHANG Bin, CHENG Guxun, LI Zuohui FOREST RESOURCES WANAGEMENT    2023, 0 (3): 38-45.   DOI: 10.13466/j.cnki.lyzygl.2023.03.006 Abstract （198）   HTML （8）    PDF （2259KB）（372）       Knowledge map    Save The large-scale invasion of Spartina alterniflora has endangered the ecological security of China's coastal area.Therefore,studying a fast and accurate algorithm for identifying Spartina alterniflora is particularly important for achieving dynamic monitoring within the region.Taking Xiangshan harbor as a research zone in this study,151 Spartina alterniflora and 140 non-Spartina alterniflora land patches were used as the training data set on the GEE platform.The index of NDVI,EVI,NDWI and BSI were extracted from the Sentinel-2 remote sensing image band information,and these indices were added to the remote sensing image data.Machine learning methods such as Support Vector Machines and Random Forests were used for identification and classification.By identifying and classifying Sentinel-2 remote sensing images from 2017 to 2022,dynamic monitoring of Spartina alterniflora within the study area was achieved.The research results showed that compared with SVM,the RF method had higher recognition accuracy for identifying Spartina alterniflora,and the overall recognition accuracy in 2022 reached 99.03% with a Kappa coefficient of 0.978 7.At the same time,the experimental results showed that the area of Spartina alterniflora in Xiangshan harbor has gradually decreased since 2017,indicating that the artificial intervention measures taken during this period were very effective.The dynamic monitoring and status analysis of Spartina alterniflora in Xiangshan harbor provided quantitative scientific data for the management of Spartina alterniflora,and have important reference value for formulating relevant prevention and control measures. Table and Figures | Reference | Related Articles | Metrics

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Assessment on Habitat Suitability of Macaca thibetana in Xianxialing Provincial Nature Reserve Using MaxEnt Modeling YU Zhucheng, XU Linli, LUO Shuigen, WANG Meifang, ZHOU Xiao, CHEN Danna, JIN Wei FOREST RESOURCES WANAGEMENT    2023, 0 (2): 111-117.   DOI: 10.13466/j.cnki.lyzygl.2023.02.015 Abstract （205）   HTML （8）    PDF （3775KB）（366）       Knowledge map    Save The Macaca thibetana is an endemic species to China.Assessment on habitat suitability Macaca thibetana is very important for the conservation,which plays an important role in the rational and scientific protection of this species.To improve the conservational strategy,by using the MaxEnt model,this study evaluated and analyzed the habitat suitability based on site data obtained by infrared camera monitoring technology and three environmental factors such as vegetation,terrain,and human interference for the Macaca thibetana in Xianxialing provincial nature reserve in Jiangshan city.The results showed:the MaxEnt model could accurately predict the spatial distribution of habitat suitability for Macaca thibetana.The moderate and high suitable habitats for Macaca thibetana were mainly distributed in the southeast,northeast,and northwest of the Reserve with high altitude and broad-leaved forests.The area of moderate and high suitable habitats was 3 041.10 hm2,accounting for 43.96% of the total area of the Reserve.Factor variable contribution analysis showed that altitude,distance from road,and slope aspect were the main factors affecting habitat quality,with contribution rates of 33.30%,29.40%,and 12.40%,respectively.Based on the results of the distribution of habitat suitability,we suggested that management department should further rationally plan the functional areas of the reserve through preventing the expansion of the bamboo forest area from causing the degradation of the broad-leaved forest,improving the connectivity between the northwest and southwest suitable habitats,and providing a safe and smooth corridor for the migration of the Macaca thibetana population. Table and Figures | Reference | Related Articles | Metrics

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Geographic Weighted Regression Model Combined with Remote Sensing for Estimating Forest Aboveground Carbon Storage of Songyang County ZOU Weimin, CHEN Chao, HUANG Lei, SONG Meixuan, LI Xuejian, DU Huaqiang FOREST RESOURCES WANAGEMENT    2023, 0 (4): 132-140.   DOI: 10.13466/j.cnki.lyzygl.2023.04.016 Abstract （158）   HTML （7）    PDF （5877KB）（353）       Knowledge map    Save Aboveground carbon(AGC)is an important indicator of the basic characteristics of forest ecosystems and a theoretical basis for evaluating the functional structure and productive potential of forests.As one of the nine key forestry counties in Zhejiang Province,Songyang County has a very important ecological status,so the accurate estimation of forest AGC in Songyang County is an important reference value for the stability evaluation of forest ecosystems and forest management in Songyang County.However,Songyang County is dominated by medium and low hilly areas surrounded by mountains,and how to consider the influence of complex terrain on the temporal and spatial variation of AGC is an urgent problem to be solved to achieve accurate estimation of AGC in mountainous forests.Therefore,based on Landsat TM satellite imagery and forest AGC survey data in Songyang County,a geographically weighted regression model(GWR)combined with spatial variation characteristics was constructed to estimate forest AGC,and compared with the results of ordinary least squares(OLS),finally,the optimal model was selected to predict forest AGC and its spatial distribution in Songyang County.The results were asfollows:Texture information from Landsat TM satellite imagerywas important for predicting forest AGC in Songyang County;The GWR model accurately estimated the AGC and spatial distribution of forests in Songyang County,and improved the accuracy by 9% over the OLS model,with an R2 of 0.71.The total AGC of forests in Songyang County was 3.901×106 Mg,with an average AGC of 23.70 Mg/hm2,accounting for about 10% of the total AGC of forest vegetation in Lishui City,which had a relatively important position in serving regional ecological functions.The study will provide advanced technical tools for accurate estimation of forest AGC in Songyang County,as well as scientific data for evaluating the function of forest carbon sink in Songyang County. Table and Figures | Reference | Related Articles | Metrics

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Biomass Distribution Characteristics and Carbon Measurement Parameters of Chinese Fir Plantation LAN Xiao, HAO Haikun, HUANG Kaiyong, CHEN Qin, DAI Jun, CHENG Lin, CHEN Shichang FOREST RESOURCES WANAGEMENT    2023, 0 (2): 50-56.   DOI: 10.13466/j.cnki.lyzygl.2023.02.007 Abstract （295）   HTML （13）    PDF （1668KB）（337）       Knowledge map    Save The purpose of this study is to explore the biomass distribution regularity of Chinese fir plantation and establish its biomass prediction model,and to provide a basis for scientific prediction and reasonable evaluation of its carbon sequestration capacity.In the study,the Chinese fir plantations of different ages and different site conditions in the typical cultivation area in Guangxi were selected as the research objects,the characteristics of rhizome ratio,wood basic density,carbon content,biomass conversion and expansion factor were analyzed by means of field biomass survey and indoor measurement.The results showed that the stem biomass of Chinese fir at different ages was the highest (40.00%~67.40%),followed by the root (14.70%~22.70%).The average rhizome ratio was 0.263,and the average wood basic density was 300.5 kg/m3.There was no significant difference in the fitting effect of different relative growth equations on stem,bark,branch,above-ground biomass,underground biomass and total biomass.The average carbon content ofall organs was 50.57%,which increased with the increase of forest age.The relationship between stem biomass and stand volume was the best with power function,and the relationship between above-ground biomass,underground biomass,total biomass and volume was best with hyperbolic model. Table and Figures | Reference | Related Articles | Metrics

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Evaluation and Optimization of Survey Methods for Ecological Factors about Wild Animals and Their Habitats YANG Xiao, HU Jiping, REN Kailei, RUAN Xiangdong FOREST RESOURCES WANAGEMENT    2023, 0 (3): 65-70.   DOI: 10.13466/j.cnki.lyzygl.2023.03.009 Abstract （295）   HTML （18）    PDF （998KB）（326）       Knowledge map    Save The field survey of the current ecological situation is the basis for the prediction and evaluation of ecological environment.However,the current field investigation methods focus on assessing the status of the ecological environment,and cannot accurately predict the potential impact of construction projects during construction and operation.Under the new situation of comprehensively strengthening the protection of wild animals,the paper innovatively introduced the concept of "relative value" for six indicators which were wildlife activity degree,species richness,the quantity of key national protected wild animals,habitat connectivity,vegetation coverage and the quantity of key national protected wild plants.Combining qualitative and quantitative technical measures,the optimization of the content,methods and data calculation methods of ecological status investigation were discussed.The optimized investigation method not only lays a foundation for the objective prediction of the potential impacts of construction projects on wildlife and their habitats,but also provides effective technical support for the early project approval and decision making.It also is of great significance to study how to coordinate the development of infrastructure construction with the protection of ecological environment. Table and Figures | Reference | Related Articles | Metrics

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Study on Tracing Pilot Work of China's National Park System MA Wei, LIU Zengli, WANG Zhichen, JIANG Yafang, TANG Xiaoping FOREST RESOURCES WANAGEMENT    2023, 0 (3): 1-8.   DOI: 10.13466/j.cnki.lyzygl.2023.03.001 Abstract （339）   HTML （41）    PDF （3035KB）（314）       Knowledge map    Save Since 2013,remarkable achievements had been made in the development of national parks in China.From the initial developement of national park system to the official establishment of the first batch of national parks and the release of the national park spatial layout plan,the leap from theory to practice had been realized.Our study focused on tracking the national park system pilots in China,sorting out and refining the pilot work at both the national level and pilot area level.By tracing the progresses of the pilot work of China's national park system,sorting out and refining the pilot work at both national and pilot area levels,comprehensively analysing and summarising the main achievements and lessons learnt at different stages of China's national park system pilot,recommendations that can be replicated and applied were put forward.In addition,we took Three-River-Source National Park as an example to trace the pilot study process to provide references for the establishment and management of national parks in China. Table and Figures | Reference | Related Articles | Metrics

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Habitat Suitability Assessment of Moose Based on Combined MaxEnt and HSI Model ZENG Haowei, LING Chengxing, ZHANG Jun, LIU Hua, ZHAO Feng, JIN Yue, LIU Shuguang, ZHANG Yutong FOREST RESOURCES WANAGEMENT    2023, 0 (4): 115-122.   DOI: 10.13466/j.cnki.lyzygl.2023.04.014 Abstract （170）   HTML （9）    PDF （3281KB）（285）       Knowledge map    Save Moose is a national first-class protected animal in China.Studying the habitat quality of moose is a key step to protect moose population.In this paper,taking Heilongjiang Nanwenghe National Natural Reserve as an example,the habitat suitability of moose was evaluated using maximum entropy model(MaxEnt)and habitat suitability index(HSI)model.Moose distribution points data was gathered from unmanned aerial vehicle transect survey,the maximum entropy model was used to get the environmental factor contribution and single environment variable response curve,combined with natural geography of the Reserve,the evaluation model was set up based on the impact of different environmental factors on moose to evaluate the moose habitat suitability of reserve quantitatively.The results showed that altitude(20.3%),slope(11.4%)and distance from river(11.3%)were the main environmental factors affecting the habitat distribution of moose,while slope aspect,slope position and vegetation coverage had less effect on moose habitat.Moose prefer to live in forested area with low altitude,moderate slope,sunny slope,and prefer to live close to river,far away from human disturbance and in areas with high coverage.In the reserve,the area of high suitable habitat for moose is 424.6 km2,accounting for 18.5% of the total area.The area of low suitable habitat is 1 422.9 km2,accounting for 62% of the total area.The area of unsuitable habitat is 447.5 km2,accounting for 19.5% of the total area. Table and Figures | Reference | Related Articles | Metrics

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The Value,Existing Problems and Development Suggestions of China's National Park Concession System WANG Tianwei, LIU Rui Forest and Grassland Resources Research    2023, 0 (6): 8-17.   DOI: 10.13466/j.cnki.lczyyj.2023.06.002 Abstract （186）   HTML （15）    PDF （1039KB）（281）       Knowledge map    Save The national park concession system is an innovation of Chinese government concessions in the field of ecological civilization construction,which not only injects funds into the construction of national parks,but also improves the quality of public services through market competition mechanism.It not only implements the basic goal of the public interest of national parks to protect the ecological environment,but also protects the personal interests of indigenous residents.However,in the process of implementation,the national park concession system still faces problems such as the questionable nature of the concession agreement,the defects of the access mechanism and the lack of systematic regulation of the exit mechanism,which hinders the effectiveness of the concession system.On this basis,the franchise agreement should be given the dual nature of both "administrative" and "civil",with an administrative license at the stage of agreement conclusion and a civil contract at the stage of agreement implementation;The franchise access mechanism should be further improved by establishing a franchise management advisory committee,restricting the use of priority renewal rights,and introducing a "negative list" management model.And through the establishment of a temporary takeover system,improve the franchise supervision system and other ways to establish an exit mechanism. Reference | Related Articles | Metrics

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Spatio-Temporal Pattern Analysis of Vegetation NPP in Yunnan Province Based on Improved CASA Model QIAN Hui, ZHANG Chao, FAN Jinming, DENG Zaichun, ZHU Xiali, LI Chengrong Forest and Grassland Resources Research    2023, 0 (6): 120-128.   DOI: 10.13466/j.cnki.lczyyj.2023.06.015 Abstract （92）   HTML （5）    PDF （4149KB）（276）       Knowledge map    Save Vegetation net primary productivity (NPP)is one of the indicators to measure the level of ecosystem productivity,it is of great significance to estimate it by using the combination of ecology and remote sensing.In this study,we applied the improved CASA model;based on the MODIS vegetation index product,meteorological data,and land cover data;estimated the vegetation NPP in Yunnan Province in 2000,2005,2010,2015,and 2020,and explored its spatial distribution characteristics using the Moran's I index,Getis-Ord Gi* hotspot analysis,and overlaying analysis with China's ecologically Functional Protected Areas in China were superimposed and analyzed.The results showed that:1)the vegetation NPP in Yunnan Province in the past 20 years showed a trend of decreasing and then increasing trend,with an average value of 822.98 gc/(m2 a);the monthly vegetation NPP reached the highest in summer and the lowest in winter;and among the different vegetation types,the evergreen broadleaf forests had the highest NPP values.2)The spatial distribution of vegetation NPP decreased from south to north in each year,and the global spatial autocorrelation Moran 's I index was greater than 0.7.The NPP hot spots were mainly located in the southwestern border of Yunnan,and the cold spots were located in the northwestern and central urbanization areas of Yunnan.3)NPP hotspot areas superimposed with ecological function reserve intersected in Xishuangbanna Ecological Function Reserve and Southwest Karst Ecological Function Reserve,and the superimposed area accounted for 23%~26% of the total area of hotspot areas in each year.The study shows that NPP in Yunnan Province has shown a fluctuating upward trend in the past 20 years,and the results can provide scientific references for vegetation monitoring and ecological environmental protection in Yunnan Province. Table and Figures | Reference | Related Articles | Metrics

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Research on the Plot Survey and Load Estimation of National Forest Fuels YANG Xueqing, SUN Zhichao, CHAI Zheng, QIU Yiwen, JIANG Chunying FOREST RESOURCES WANAGEMENT    2022, 0 (6): 1-6.   DOI: 10.13466/j.cnki.lyzygl.2022.06.001 Abstract （700）   HTML （75）    PDF （934KB）（262）       Knowledge map    Save From the viewpoint of tediousness and professionalism of forest fuel load investigation,a stratified sampling system for the plot survey of forest fuel loads at national and provincial scale were developed based on five commonly used indicators,namely vegetation area,tree species,stand origin,age group and canopy density.Within each specific plot,the fuel loads of tree-layer can be estimated by using the data of individual tree survey combined with the algometric biomass model or the biomass expansion factor,while fuel loads of shrub-,herb-,litter- and humus-layer should be jointly estimated by the quadrat survey and the data of sample moisture content.This method has important guidance and reference significance for the survey and estimation of forest fuel loads at national or regional scale. Table and Figures | Reference | Related Articles | Metrics

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Single-Tree Crown Delineation in Plain Afforestation Areas Based on Mask R-CNN XING Yuanjun, WEN Kunjian, GUO Xiaoni, SONG Yabin, HU Zhongyue, JIANG Tengyu, HE Zijing FOREST RESOURCES WANAGEMENT    2023, 0 (3): 115-120.   DOI: 10.13466/j.cnki.lyzygl.2023.03.015 Abstract （194）   HTML （6）    PDF （5403KB）（259）       Knowledge map    Save This paper aims to investigate an automated approach for extracting spatial distribution and quantities of planted trees in plain areas by using of visible light imagery obtained from unmanned aerial vehicles.Specifically,the study focuses on analyzing afforestation patches located in Huailai,Zhangjiakou,Hebei Province.To achieve this,a manually constructed single-tree crown dataset was utilized to train and predict Mask R-CNN models with varying backbone networks(R50-FPN-1x,R50-FPN-3x,R101-FPN-3x),and their accuracies were compared on an independent test set.Results indicate that all backbone models were able to segment tree crowns in the afforested areas,with the R101-FPN-3x model achieving the highest accuracy of 75.33% and a recall rate of 73.23%.The results showed that the single tree segmentation method based on Mask R-CNN from UAV images could quickly and accurately detect single tree targets in afforestation areas automatically,and effectively segment single tree crown to map the crown contour,which could meet the needs of efficient investigation and monitoring in small and medium-sized plain afforestation areas. Table and Figures | Reference | Related Articles | Metrics