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A PROJECT OF SUSTAINABLE UTILIZATION OF FOREST RESOURCES SUPPORTED BY GIS 被引量:1
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作者 ZANG Shu-ying(Derartment of Geography, Harbin Normal University, Harbin 150040, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2000年第2期188-192,共5页
This paper, with the help of GIS, analyzes the structure characteristics, dynamic process and factors which result in failure of forest resources sustainable development in Tayuan Forest Farm, Da Hinggan Mountains, fi... This paper, with the help of GIS, analyzes the structure characteristics, dynamic process and factors which result in failure of forest resources sustainable development in Tayuan Forest Farm, Da Hinggan Mountains, finds that there are big problems either in quantity or in Planning for forest resource development, and puts forward a project for its forest resources sustainable utilization. From the analysis, this paper is going to find an available develoment project for forest resourees sustainabe utlization for the forest farm, and also provides the proection and management of forest resources and the strategy of sustainable forestry development with scienndc foundation. 展开更多
关键词 forest RESOURCES sustainable UTILIZATION project GIS
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Effectiveness Evaluation of the Construction of the Natural Forest Resources Protection Project in Haikou Forest Farm of Kunming
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作者 ZHANG Zhihong WANG Yating +1 位作者 CHEN Jinlong YAN Yi 《Journal of Landscape Research》 2018年第2期42-44,共3页
The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, fo... The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, forest pests, and money management was briefed. Achievements made in the implementation of natural forest protection project in Haikou Forest Farm were analyzed, and problems existing in the project as well as corresponding countermeasures were expounded. 展开更多
关键词 Haikou forest Farm Natural forest protection project Effectiveness evaluation SUGGESTION
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SWOT Analysis of Forest Carbon Sink Projects in Yunnan Province and Recommendations for Enhancing Competitiveness
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作者 Xiaolin FANG Lan GAO Jing ZHAO 《Asian Agricultural Research》 2020年第11期20-23,共4页
Using the SWOT analysis method,this paper analyzed the internal strengths,weaknesses,external opportunities and threats of forest carbon sink projects in Yunnan Province.It found that Yunnan Province has strengths in ... Using the SWOT analysis method,this paper analyzed the internal strengths,weaknesses,external opportunities and threats of forest carbon sink projects in Yunnan Province.It found that Yunnan Province has strengths in economic environment and practical experience,weaknesses in social participation,project scale and carbon sink talents,opportunities in international climate environment,domestic policies,etc.,and threats in project crediting period and forest resource protection,etc.In view of these,Yunnan Province can change the participation mode of forest carbon sink projects,adopt appropriate trading methods,get familiar with the relevant rules of forest carbon sink projects,strengthen the publicity and research of forest carbon sink theory,strengthen the management of carbon sink forests and expand forest carbon sink projects to enhance the market competitiveness of the Yunnan forest carbon sink projects. 展开更多
关键词 forest carbon sink projects SWOT analysis Yunnan Province
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Coastal Protection Forest Construction Project
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《China's Foreign Trade》 1995年第9期18-18,共1页
China’s coastal line starts at the Yalu River in Liaoning in the north and ends at the Beilun River mouth in Guangxi. It is 18,000 kilometres long and crosses 11 provinces, municipalities and autonomous regions, incl... China’s coastal line starts at the Yalu River in Liaoning in the north and ends at the Beilun River mouth in Guangxi. It is 18,000 kilometres long and crosses 11 provinces, municipalities and autonomous regions, including Liaoning, Hebei, Tianjin, Shandong, Jiangsu, Shanghai, Zhejiang, Fujian, Guangdong, Guangxi and Hainan. In 1988, the Chinese government outlined the Coastal Protection Forest System Construction Project and defined the coastal line of 11 provinces as the main construction line. The project aims at developing a 展开更多
关键词 Coastal Protection forest Construction project LINE
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Analysis of Factors Influencing Forest Carbon Sequestration Project in Guangdong Province and Recommendations
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作者 Xiaolin FANG Lan GAO 《Asian Agricultural Research》 2018年第11期39-42,共4页
Through designing questionnaires for farmers in the project area,the understanding and utilization of carbon sink forests were surveyed. In the form of stratified sampling,150 representative forest farmers were select... Through designing questionnaires for farmers in the project area,the understanding and utilization of carbon sink forests were surveyed. In the form of stratified sampling,150 representative forest farmers were selected from the project area. Through the survey,it found that many factors hindered the progress of forest carbon sequestration project in Guangdong Province. Besides,the implementation of this project was influenced by both natural and social factors. As to the natural factors,natural disasters for the forest carbon sequestration project in Guangdong Province mainly include typhoons,rainstorms,landslides and mudslides. The social factors of the forest carbon sequestration project in Guangdong Province mainly include the weak willingness of forest farmers to participate,the low awareness of forest farmers for forest carbon sinks,the single and insufficient source of afforestation funds,and the single afforestation model. In order to better implement the forest carbon sequestration project,Guangdong Province can take measures such as strengthening the publicity on forest carbon sinks,expanding channels of funds,organizing forest carbon exchange training courses,and diversifying the afforestation models. 展开更多
关键词 农户调查问卷 自然灾害 林业 发展现状
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A system dynamics model for billion trees tsunami afforestation project of Khyber Pakhtunkhwa in Pakistan:Model application to afforestation activities 被引量:1
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作者 Naila NAZIR Aqsa FAROOQ +1 位作者 Sajjad AHMAD JAN Aftab AHMAD 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2640-2653,共14页
As part of the global effort to plant billion trees,an afforestation project is launched in Pakistan in Khyber Pakhtunkhwa(KP)province to conserve existing forests and to increase area under forest cover.The present s... As part of the global effort to plant billion trees,an afforestation project is launched in Pakistan in Khyber Pakhtunkhwa(KP)province to conserve existing forests and to increase area under forest cover.The present study is designed to build a Systems'model by incorporating major activities of the Billion Tree Tsunami Afforestation Project(BTTAP)with special focus on afforestation activities to estimate the growth in forest area of KP.Availability of complete dataset was a challenge.To fix the model,the raw data taken from the project office has been utilized.Planning Commission Form 1-Phase I&II helped us with additional information.We relied on the data available for one and half period of the project as rest of the data is subject to the completion of the project.Our results show that the project target to enhance area under forest differs from the target to afforest area under the project.The system dynamics'model projection shows that the forest area of KP would be 23.59 million hectares at the end of the BTTA project,thus having an increase of 3.29%instead of 2%that has been initially proposed.However,the results show that the progress to meet the target in some afforestation classes is slow as compared to other categories.Farm forestry,plantation on communal lands and owners'plantation need special focus of the authority.Deforestation would affect 0.02 million hectares area of the project.The model under study may be used as a reference model that can be replicated to other areas where billion tree campaigns are going on. 展开更多
关键词 Billion trees project AFforestATION System dynamic model forest area DEforestATION Pakistan
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Designing a Citizen Science Project for Forest Landscapes: A Case from Hofmann Forest in Eastern North Carolina
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作者 Meredith Hovis Frederick Cubbage Diana Rashash 《Open Journal of Forestry》 2020年第2期187-203,共17页
Citizen science is a participatory research design that utilizes both non-professional researchers and professional researchers to collect, analyze, and disperse data. Citizen scientists seek to discover answers and d... Citizen science is a participatory research design that utilizes both non-professional researchers and professional researchers to collect, analyze, and disperse data. Citizen scientists seek to discover answers and draw solutions to scientific questions. The Hofmann Open Water Laboratory (HOWL) project, established in 2016, focuses its collaborative-based efforts in eastern North Carolina. HOWL citizen scientists monitor water quality, and quantity, that flows on and off the Hofmann Forest. HOWL provides opportunities to citizen scientists and gathers data to meet the project outcomes, which include understanding the importance of Hofmann Forest in the inner coastal plain of North Carolina, building science education skills for citizen science participants, and enhancing community relationships between the forest and citizens. This article outlines several approaches for developing citizen science projects in a forest context, drawing on experiences from HOWL. The paradigm can be used to meet the needs of any forest landscape’s research and management goals, while employing a participatory research approach. The guidelines present suggestions for productive and enduring processes for citizen engagement and project sustainability. Each project will need participants to set goals, build a diverse collaboration, and establish on-going evaluation processes to determine successful and failed components that ensures the project moves forward effectively. The citizen science efforts near the Hofmann Forest in Eastern North Carolina provided an excellent case study of the development of citizen science on the forest and adjacent lands. HOWL attempts to meet participant and socio-ecological outcomes, such as encouraging public action in natural resource and forest management, as well as enhancing scientific knowledge and skills. The project helps synthesize our experiences in this effort and the social science literature, providing reasonable guidelines for those seeking to establish their own citizen science efforts within a forest context. 展开更多
关键词 CITIZEN Science forest Landscapes forest Context Public PARTICIPATION project Design
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Project to Protect Natural Forests
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《China's Tibet》 2002年第3期16-16,共1页
Gungjor County in Qamdois situated on the middlesection of the Jinsha-jiang River,on the upperreaches of the Yangtze Riverand in the northern part ofHenduan Mountains.Foreststhere total 220,198 hectares,and the forest... Gungjor County in Qamdois situated on the middlesection of the Jinsha-jiang River,on the upperreaches of the Yangtze Riverand in the northern part ofHenduan Mountains.Foreststhere total 220,198 hectares,and the forested area totals60,791 hectares.They com-bine to function as a naturalscreen on the Yangtze’s upperreaches. 展开更多
关键词 project to Protect Natural forests
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“工程治沙”新模式:机械化专业技术服务队
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作者 杨建华 刘恒 +3 位作者 戴蕙泽 吴立国 张明远 周建波 《林业机械与木工设备》 2025年第1期20-26,共7页
随着沙漠化问题的日益严重,传统的治沙方法已经难以满足现代生态环境保护的需求。提出了一种新型的“工程治沙”模式——机械化专业技术服务队的概念,这是一种结合现代化技术和机械化操作的高效治沙新策略。首先,介绍了三北防护林工程... 随着沙漠化问题的日益严重,传统的治沙方法已经难以满足现代生态环境保护的需求。提出了一种新型的“工程治沙”模式——机械化专业技术服务队的概念,这是一种结合现代化技术和机械化操作的高效治沙新策略。首先,介绍了三北防护林工程建设的现状;其次,就工程治沙的技术方法和机械设备进行了深入探讨;最后,结合土地沙漠化治理现状和现有装备技术,给出了工程治沙机械化专业技术服务队的人员组成、作业规程以及装备配置。总之,机械化专业技术服务队作为“工程治沙”的一种新模式,不仅优化了治沙技术,还为沙区的生态恢复和可持续发展提供了新的思路和方法。未来,这种模式有望在更广泛的区域得到应用,并为全球抗击沙漠化问题贡献力量。 展开更多
关键词 工程治沙 机械化 服务队 三北工程
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结合Rotation Forest和MultiBoost的SVM集成方法 被引量:1
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作者 姚旭 王晓丹 +1 位作者 张玉玺 毕凯 《计算机科学》 CSCD 北大核心 2013年第3期266-270,290,共6页
针对如何提高集成学习的性能,提出一种结合Rotation Forest和MultiBoost的集成学习方法——利用Ro-tation Forest中旋转变换的思想对原始数据集进行变换,旨在增加分类器间的差异度;利用MultiBoost在变换后的数据集上训练基分类器,旨在... 针对如何提高集成学习的性能,提出一种结合Rotation Forest和MultiBoost的集成学习方法——利用Ro-tation Forest中旋转变换的思想对原始数据集进行变换,旨在增加分类器间的差异度;利用MultiBoost在变换后的数据集上训练基分类器,旨在提高基分类器的准确度。最后用简单的多数投票法融合各基分类器的决策结果,将其作为集成分类器的输出。为了验证该方法的有效性,在公共数据集UCI上进行了实验,结果显示,该方法可获得较高的分类精度。 展开更多
关键词 集成学习 支持向量机 随机投影 旋转森林 MultiBoost
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Assessing current stocks and future sequestration potential of forest biomass carbon in Daqing Mountain Nature Reserve of Inner Mongolia, China 被引量:3
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作者 Yahui Sun Li Meng +2 位作者 Lü Tian Guoliang Li Osbert Jianxin Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期931-938,共8页
Assessment of regional forest carbon stocks and underlying controls is critical for guiding forest management in the context of carbon sequestration. We investigated the variations in tree biomass carbon stocks relati... Assessment of regional forest carbon stocks and underlying controls is critical for guiding forest management in the context of carbon sequestration. We investigated the variations in tree biomass carbon stocks relating to forest types, and estimated the total tree biomass carbon stocks and projected gains through natural stand development by 2020 and 2050 in the Daqing Mountain Nature Reserve based on Category II data of the Forest Inventory of Inner Mongolia for the period ending 2008. Over a total area of 388,577 ha,this nature reserve currently stores an estimated 2221 Gg C in tree aboveground biomass alone, with potential to grow by more than 30 % to reach 2938 Gg C by 2020 and nearly double to 4092 Gg C by 2050 through natural development of the existing forest stands. The tree biomass carbon density and potential gain in tree biomass carbon stocks vary markedly among forest types and with stand development.The variations in the potential change of tree biomass carbon density for the periods 2008–2020 and 2008–2050 among forest types partly reflect the varying relationships of tree biomass carbon density with stand age for different tree species, and partly are attributable to variations in the stand age structure among different forest types. Of the major forest types, the ranking of projected changes in tree biomass carbon density are not consistent with variations in the relationship between tree biomass carbon density and stand age, neither are they explainable by variations in stand age structures, implying the interactive effect between forest type and stand dynamics on temporal changes in tree biomass carbon density. Birch rank highest for future biomass carbon sequestration because of its dominance in cover area and better age structure for potential gain in tree biomass carbon stocks. Poplar and larch were out-performers compared to other forest types given their greater contribution to total tree biomass carbon stocks relative to their distributional areas. Findings in this study illustrate that protection and proper management of under-aged forests can deliver marked gains in biomass carbon sequestration. This is of great importance to policy-makers as well as to scientific communities in seeking effective solutions for adaptive forest management and mitigation of anthropogenic greenhouse gases emissions using forest ecosystems. 展开更多
关键词 sequestration biomass stocks stand forests Reserve Birch projected gains anthropogenic
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Evaluation of the Land Production Potential in the Context of Returning Farmland to Forest in Karst Region:A Case Study of Guizhou Province 被引量:2
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作者 Shuang YU Guang LI Ruiping RAN 《Asian Agricultural Research》 2013年第1期21-26,共6页
In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test ... In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test on the actual production capacity of land and the forecasted production capacity of land in 2007 and 2008, and then conduct comprehensive forecast of the land production potential in Guizhou Province in 2020. On this basis, considering the nutritional standards needed by three kinds of life type (dressing warmly and eating one's fill, well-off life, relatively affluent life), we evaluate the land production potential in Guizhou Province under the project of returning farmland to forest. Based on the evaluation results, we put forth the relevant recommendations for achieving sustainable land use in the context of returning farmland to forest in Guizhou Province. 展开更多
关键词 KARST region project of RETURNING FARMLAND to fore
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REDD+ benefit sharing under models tested by pilot projects in Tanzania:Inputs towards developing national benefit-sharing mechanism models
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作者 Shemdoe Riziki Silas 《Chinese Journal of Population,Resources and Environment》 2016年第1期38-44,共7页
This paper presents results of the assessment on benefit sharing and payment mechanisms tested by six non-governmental organizations(NGOs)-piloted Reducing Emissions from Deforestation and Forest Degradation(REDD+) in... This paper presents results of the assessment on benefit sharing and payment mechanisms tested by six non-governmental organizations(NGOs)-piloted Reducing Emissions from Deforestation and Forest Degradation(REDD+) initiatives in Tanzania.Results from the assessment indicate that models applied by most of the REDD+ pilot projects have provided most of decisions for the distribution of benefits to the communities through village general assemblies.Based on requirements of the tested models,national benefit-sharing mechanism models are proposed.Major attributes to be considered in the development of national benefit-sharing models should include:(i) ensuring that the existing government structure is not excluded to ensure sustainability;(ii) village general assembly is involved in determining the distribution of the benefits accrued;and(iii) transparency in handling the carbon finance is ensured.Models that are proposed for the national REDD+ benefit sharing apply to two forest management systems,namely Joint Forest Management(JFM) and Community Based Forest Management(CBFM).The paper recommends testing of the two proposed models to determine whether they could be useful in sharing benefits resulting from REDD+ in Tanzania. 展开更多
关键词 forest management systems developmental projects REDD+ payments
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Floristic Inventory and Evaluation of Carbon Sequestration Potential of the Misomuni Forest Massif,Kikwit City (Democratic Republic of the Congo)
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作者 Masens Da-Musa Y.B. Briki K.Cyril +1 位作者 Masens Mandung Koto-Te-Nyiwa Ngbolua 《Journal of Botanical Research》 2021年第4期11-21,共11页
The aim of this study was to inventory plant biodiversity and to evaluate the carbon sequestration potential of the Misomuni forest massif.An inventory of all trees with diameter at breast height(dbh)≥10 cm measured ... The aim of this study was to inventory plant biodiversity and to evaluate the carbon sequestration potential of the Misomuni forest massif.An inventory of all trees with diameter at breast height(dbh)≥10 cm measured at 1.30 m height was performed.The aerial biomass(AGB)was used for estimating the stored CO2 and its carbon equivalent.88 plant species belonging to 71 genera and 32 families were inventoried.Fabaceae family displayed the highest number of species and genera.The highest basal area values were displayed by Scorodophloeus zenkeri(7.34±2.45 m2/ha),Brachystegia laurentii(5.82±1.94 m2/ha),Entandrophragma utile(5.28±1.94 m2/ha),Pentadesma butyracea(4.53±1.51 m2/ha).The highest values of stored carbon and their carbon equivalent were observed in Pentadesma butyracea(15.13±5.00 and 50.55±16.85 t/ha),Picralima nitida(7.02±2.34 and 23.66±7.88 t/ha),Strombosia tetandra(6.56±2.18 and 22.10±7.36 t/ha).The Misomuni forest massif is thus much floristically diversified and plays a significant role in the sequestration of CO2.The total AGB of the inventoried trees is 183.78±61.26 t/ha corresponding to stored carbon and carbon equivalent of 96.63±32.21 t/ha and 289.92±96.64 t/ha respectively.The protection of this ecosystem is highly needed for combatting climatic changes at local,national and regional scales and for the conservation biodiversity habitat. 展开更多
关键词 forest ecosystem Plant biodiversity Carbon sequestration Reducing Emissions from Deforestation and forest Degradation project Democratic Republic of the Congo
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阿克苏地区天然林保护工程区植被覆盖度变化及驱动因子研究
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作者 康娟 方贺 +2 位作者 石守海 夏瑞 彭金灵 《测绘通报》 CSCD 北大核心 2024年第5期41-47,共7页
本文以阿克苏地区天然林保护工程区为研究区域,基于MODIS卫星影像资料,首先利用像元二分法模型制作了研究区2000—2020年生长季(5—9月)植被覆盖度产品,然后分析了长时序植被覆盖度时间变化规律和空间分布特征,最后利用地理探测器模型... 本文以阿克苏地区天然林保护工程区为研究区域,基于MODIS卫星影像资料,首先利用像元二分法模型制作了研究区2000—2020年生长季(5—9月)植被覆盖度产品,然后分析了长时序植被覆盖度时间变化规律和空间分布特征,最后利用地理探测器模型分析植被覆盖度变化驱动机制。结果显示,2000—2020年阿克苏天保区植被覆盖度以0.23%/a的速度呈显著上升趋势,植被覆盖度显著增加面积占比达50.4%。在众多影响因子中,土地利用是影响研究区植被覆盖的主要影响因子,解释力达0.59;人口密度、蒸散发及GDP对植被的解释力是次要影响因子,分别为0.360、0.357、0.308。本文有助于更好地理解人类活动和自然因素对植被生态质量变化的影响及其相互作用机制。 展开更多
关键词 植被覆盖度 遥感 阿克苏地区 天然林保护工程 地理探测器
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湖南省权益类森林生态产品价值实现的问题与对策
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作者 刘见 张运明 +2 位作者 曹兰芳 周训芳 李敏 《湖南林业科技》 2024年第4期96-100,共5页
权益类森林生态产品是一类需要政府赋权和确权并通过市场实现生态价值的生态产品,具有不完全的排他性和竞争性特征,依靠政府与市场共同作用实现生态价值。湖南省探索开发了林业碳汇项目、集体林权、林权抵押贷款等三种权益类森林生态产... 权益类森林生态产品是一类需要政府赋权和确权并通过市场实现生态价值的生态产品,具有不完全的排他性和竞争性特征,依靠政府与市场共同作用实现生态价值。湖南省探索开发了林业碳汇项目、集体林权、林权抵押贷款等三种权益类森林生态产品,取得了积极成效,但依然在运行机制、配套政策等方面存在亟待解决的问题。政府应当采取优化林业碳汇项目开发、推动集体林权交易监管协同、打通林权抵押贷款通道等举措,推动权益类森林生态产品价值实现。 展开更多
关键词 权益类森林生态产品 林业碳汇项目 集体林权交易 林权抵押贷款
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东北天然林资源保护工程成效评估及热点区域识别 被引量:4
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作者 王佳琪 邢艳秋 +1 位作者 常晓晴 杨红 《生态学报》 CAS CSCD 北大核心 2024年第3期1231-1241,共11页
东北地区天然林资源保护工程的实施,改善了生态环境,提高了生态系统服务能力,对东北地区生态系统服务也起到了积极促进作用。为了更直观的反映东北地区天保工程的实施成效,研究基于长时间序列的遥感监测数据集-土地利用数据,采用InVEST... 东北地区天然林资源保护工程的实施,改善了生态环境,提高了生态系统服务能力,对东北地区生态系统服务也起到了积极促进作用。为了更直观的反映东北地区天保工程的实施成效,研究基于长时间序列的遥感监测数据集-土地利用数据,采用InVEST模型和RUSLE模型对1990—2020年天保工程实施前后东北地区和天保工程区生态系统服务变化进行定量评估分析并采用Getis-Ord Gi∗指数识别热点区域。结果表明:(1)东北地区1990—2020年城乡/工矿居民用地和耕地面积分别增加25.37%,12.15%,水域减少21.42%,草地减少14.02%,未利用土地和林地分别减少8.41%,5.34%。(2)1990—2020年东北地区和天保工程区土壤保持量分别增加了95.81×106 t、24.05×10^(6) t,碳储量分别减少了7.49×10^(8) tC、3.92×10^(8) tC,水源涵养量分别增加了177.51×10^(9) m^(3)、58.65×10^(9) m^(3)。(3)东北地区的极显著热点区域主要分布内蒙古地区东北部、黑龙江省北部、吉林省东部和辽宁省东部。随着天保工程的实施,极显著热点区域显著增加,且范围与天保工程高度重合。研究拟为后续东北地区林业政策和生态工程的实施提供科学的参考依据。 展开更多
关键词 生态系统服务 天然林资源保护工程 热点分析 INVEST RUSLE
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基于InVEST模型的大兴安岭天保工程区碳储量时空变化研究 被引量:2
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作者 张宇飞 王子昊 +1 位作者 王冰 张秋良 《西部林业科学》 CAS 北大核心 2024年第1期108-118,共11页
为给大兴安岭天保工程区生态系统保护和土地利用规划提供科学依据,以大兴安岭天保工程区为研究区,基于研究区2000—2020年土地利用数据和各地类碳密度数据,运用InVEST模型碳储量模块对大兴安岭天保工程区2000—2020年生态系统的碳储量... 为给大兴安岭天保工程区生态系统保护和土地利用规划提供科学依据,以大兴安岭天保工程区为研究区,基于研究区2000—2020年土地利用数据和各地类碳密度数据,运用InVEST模型碳储量模块对大兴安岭天保工程区2000—2020年生态系统的碳储量进行估算,并通过土地利用转移矩阵分析土地利用类型之间的相互转化对碳储量的影响。结果显示:(1)研究区2000、2005、2010、2015、2020年碳储量分别为569.87×10^(7)、573.22×10^(7)、573.69×10^(7)、572.42×10^(7)、573.14×10^(7) t,呈增加趋势,累计增加3.27×10^(7) t;(2)碳储量较高的地区主要分布在北部和中部,较低的区域主要分布西部、南部、东南角和东部小区域;(3)林地是研究区最重要的碳库,其碳储量占研究区固碳总量的93.31%,林地和耕地面积的增加是大兴安岭天保工程区碳储量增加的主要原因。研究结果表明:天保工程促使大兴安岭林地面积保持稳定并且呈现出一定增长趋势,提高了大兴安岭的整体固碳能力。在未来,大兴安岭应当继续实施和巩固天然林保护工程,继续坚持退耕还林还草政策,通过合理的行政规划,调控草地和耕地向建设性用地转换;此外,通过人工种植、草畜平衡的政策,围栏封育和优化种苗的方式来缓解草地退化,修复草地生态系统;而耕地则通过间作套作、改良品种、合理使用肥料等方法提高产量。 展开更多
关键词 大兴安岭 天然林保护工程 InVEST模型 碳储量 时空变化
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基于随机森林优化RL的电力工程造价预测
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作者 张文静 刘云 +2 位作者 周波 洪崇 王立功 《沈阳工业大学学报》 CAS 北大核心 2024年第6期754-759,共6页
针对现阶段电力工程造价数据预测准确度较低的问题,提出了一种基于随机森林优化RL的相关预测算法。通过分析影响电力工程造价的因素,将其按照影响程度的大小进行分级,利用随机森林算法加以筛选,并采用筛选后的影响因素特征向量作为预测... 针对现阶段电力工程造价数据预测准确度较低的问题,提出了一种基于随机森林优化RL的相关预测算法。通过分析影响电力工程造价的因素,将其按照影响程度的大小进行分级,利用随机森林算法加以筛选,并采用筛选后的影响因素特征向量作为预测模型的训练和测试数据。同时,将电力工程造价预测问题转化为输电线路规划问题,再使用强化学习优化蚁群算法的参数来构建电力工程造价预测模型。经过实验对照,综合两种栅格尺寸结果,所提方案比两种对照组算法的电子工程造价分别降低了2.97%、3.78%。 展开更多
关键词 输变电工程 工程造价 随机森林 强化学习 蚁群算法 输电线路规划 数据预测 特征向量
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社会资本与林农林业碳汇项目参与——基于交易费用经济学视角 被引量:2
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作者 席子立 潘焕学 秦涛 《重庆社会科学》 CSSCI 北大核心 2024年第1期101-119,共19页
作为林地最主要的经营主体,林农的参与是林业碳汇项目开发的首要环节。考虑到中国“关系型”社会的特征以及由此产生的交易费用问题,基于交易费用经济学视角,结合社会资本理论剖析林农参与林业碳汇项目的内在机理,同时利用宁陕县微观农... 作为林地最主要的经营主体,林农的参与是林业碳汇项目开发的首要环节。考虑到中国“关系型”社会的特征以及由此产生的交易费用问题,基于交易费用经济学视角,结合社会资本理论剖析林农参与林业碳汇项目的内在机理,同时利用宁陕县微观农户调研数据分析社会网络、社会信任与社会规范是否会影响林农林业碳汇项目参与决策并检验社会资本变量发挥作用的条件,研究表明:89%的样本林农参与了林业碳汇项目,显现出了较高的参与水平;Logit模型结果表明强关系网络、人际信任、制度信任、惩罚机制与互惠行为变量均对林农林业碳汇项目参与具有显著促进作用,而弱关系网络变量并不会影响到林农的林业碳汇项目参与决策;调节效应模型的结果则表明林农的合作社社员身份可以显著地增强社会资本各维度对林农林业碳汇项目参与的正向影响。 展开更多
关键词 林农参与 林业碳汇项目 社会资本 交易费用
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