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281.
New institutional economists have argued that there are many categories of institutions, including market and non-market institutions, which may prove economically efficient, specifically for public goods and common pool goods. The Government of India introduced a non-market community-based institution, known as Joint Forest Management (JFM), for forest management and protection in 1990. JFM is a sharing mechanism for forest planning and management based on sharing of rights and duties, control and decision-making authority over forestlands, between forest departments and local user groups. By 2001, 42 000 Village Forest Committees established under JFM were managing over 11.5 million ha forestland. These institutions have proved very useful, and have contributed to forest management as well as four aspects of sustainable human development (SHD) – ecological output, income generation, village infrastructure development, and community empowerment. In the long-term, community-based institutions will prove to be a foundation of SHD and participatory democracy. 相似文献
282.
A simple method for the quantitative gradient analysis of a xerotermic forest-margin ecotone is described. In this method, the mean value of the coefficient of similarity between all plots of the transect is used for estimating the rate of changes in species composition. Changes in the phytosociological spectrum are analyzed. The method adequately reflects trends in the displacement of forest species by forest-margin, steppe, and meadow species. 相似文献
283.
Richard J. Brazee 《中国人口.资源与环境(英文版)》2010,8(3)
Chinese forest resources have become very scarce in the face of rapid economic growth demand, while the reform of collective forest right system is in full swing across the country. It will directly affect the regeneration level of forest resources and the diverse ecological value functions. In this article, the mainstream model paradigm of forest economics, that is, the basic framework of the Faustmann model and its evolution process are made in a more detailed explanation, especially the extended model in... 相似文献
284.
General trends in simplification of the structure and composition of forest communities in the zone of impact from the metallurgical industry are revealed. The load of toxicants is estimated from the concentrations of heavy metals in the snow and soil. The method is proposed for assessing biological damage on the basis of the main characteristics of phytocenosis, such as its species diversity and the cenotic significance of its structural components. The resultant integrated index of phytocenosis preservation (IIP
p) characterizes the degree of biological damage, and its value depends on the load of toxicants and resistance of plant communities characteristic of different natural zones. 相似文献
285.
In the current stage of Chinese forest ownership reform, the central and local governments as well as the forest farmers play different roles with variations in their expected returns. Managing these respective relationships between the forestry stakeholders to maximize their benefits while actively engaging each stakeholder in the collective forest ownership reform process has become an important issue. This study uses the game theory methodology to analyze the relationship between the different reform stakeholders and then builds on the forest farmers’ participation in the reform model process at the reform movement micro-level. This model calculates the forest products equilibrium marketing sales and the government subsidies provided to the forest farmers, when the forest farmers willingly participate in the reform process. It will provide a reliable basis for formulation of government policies which positively impacts Chinese forestry reform. 相似文献
286.
Ordination of Plant Communities in Forest Biogeocenoses under Conditions of Air Pollution in the Northern Kola Peninsula 总被引:1,自引:0,他引:1
The species diversity and structure of the tree, herb–dwarf shrub, and moss–lichen layers in the biogeocenoses (BGCs) of pine forests of the Kola Peninsula were analyzed in the zone affected by the Pechenganikel Combined Works. Relationships of the diversity of phytocenoses with the amount of atmospheric fallout and the concentrations of accessible compounds of polluting elements (nickel and copper) and nutrients (potassium, magnesium, and nitrogen) in forest litters were revealed. 相似文献
287.
Perceived Impacts of Ecotourism on Environmental Learning and Conservation: Turtle Watching as a Case Study 总被引:1,自引:0,他引:1
Clem?TisdellEmail author Clevo?Wilson 《Environment, Development and Sustainability》2005,7(3):291-302
Using a case study, involving turtle-based ecotourism, we explore the role of ecotourism in promoting environmental learning
and in sustaining conservation of nature. Mon Repos Conservation Park (an important marine turtle rookery involved in ecotourism)
in Queensland, Australia, was selected for this study and visitors were surveyed using a structured questionnaire. The reported
on-site experiences of respondents are analysed to identify important factors that alter their stated conservation attitudes
and behaviours. The impact of these factors (such as the amount of environmental education that respondents claimed they obtained,
sighting of sea turtles, nationality) is quantified using regression analyses. There has been little previous quantification
of such influences. The study reveals that a considerable amount of environmental knowledge is gained by visitors to Mon Repos.
The ecotourism experience, involving environmental education and seeing of turtles, was found to have positive and statistically
significant impacts on the visitors' stated desire and intended behaviour to protect sea turtles. The study reveals the importance
of learning and the interaction of tourists with wildlife as a contributor to their pro-conservation sentiments and actions.
It shows how ecotourism can support nature conservation.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
288.
温室气体上升导致的全球气候变暖问题不容忽视,增加森林碳汇和木质林产品碳储是缓解温室效应的有效途径。根据森林碳汇功能与林产品碳储功能的关联理论与模型,推导和改进包括森林子碳库、土壤子碳库及木质林产品子碳库在内的林业碳库核算模型及方法,以实现目标碳从森林碳库向木质林产品碳库的过渡与转移。基于气候变化背景下森林-林产品产业链的发展现状,构建包括森林子碳库和林产品子碳库的复合一体化林业碳库模型,使之为中国林业碳库的计量与评价提供判据。首先,对包含森林子碳库和木质林产品子碳库在内的世界林业碳库的发展现状进行探讨,归纳和比较国内外主流的关联林业碳库评估方法模型,从而对中国林业碳库模型的构建提供理论背景支持和逻辑方法支撑。其次,分析现有中国林业碳库评估存在的优势和弊端,找出适合中国林业特点的国家碳库创新评估路径,运用政府间气候变化专门委员会指定的生产法的思路,通过分析目标碳在林产品产业链生产、加工等过程中的流入和支出,提出创新中国林业碳库的模型构想并对其系统内涵进行分析。最后,赋予中国林业碳库系统模型数学表达,分析其数理结构并进行逻辑演绎,在森林子碳库和木质林产品子碳库两个复合链式体系下构建中国林业碳库系统测度模型(ForestProducts Carbon Model/FPCM)。 相似文献
289.
中国实施生态旅游认证的机遇与挑战 总被引:18,自引:0,他引:18
在界定生态旅游认证、分析建立生态旅游认证体系意义的基础上.对绿色环球21、澳大利亚的NEAP、厄瓜多尔的Smart Voyager等目前国际知名的认证体系进行了介绍.重点分析了中国实施生态旅游认证的机遇和面临的挑战,并对我国建立生态旅游认证体系的必要性及相关问题提出了建议。 相似文献
290.
庐山不同森林植被类型土壤特性及其健康评价 总被引:2,自引:0,他引:2
土壤作为森林生态系统的一个重要因子,评价森林土壤健康状况对森林健康的维护经营以及森林系统功能的发挥具有重要意义。在系统调查和分析庐山8种森林植被类型土壤特性的基础上,评价指标分别从物种多样性以及不同的森林土壤特性中进行筛选,包括物种多样性系数、枯落物层厚度、腐殖质层厚度、土层厚度、容重、粘粒含量、有机质、p H值、阳离子交换量、全氮、水解氮、有效磷、速效钾、磷酸酶活性等指标,基于SPSS19.0软件对所获得数据进行差异性检验和相关分析,确定各项指标的权重,应用合适的土壤健康评分函数,将测得的指标值转换为对应指标的分值,最后通过加权综合法,计算其土壤健康指数,并对不同森林植被类型土壤健康状况进行评价。结果表明,8种森林植被类型下最终的土壤健康指数大小排序为:针阔混交林(0.78)常-落混交林(0.72)灌丛(0.69)常绿阔叶林(0.67)落叶阔叶林(0.64)竹林(0.59)马尾松林(0.53)黄山松林(0.46)。 相似文献