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1.
围绕中国碳中和目标的实现路径与模式选择问题,提出了一个中国应对气候变化整体治理模式,即多阶段混合主导型碳中和实现模式。这一模式是以国家为核心,在一定时期和内外环境约束下,通过减排和增汇路径,对中国境内由人类活动造成的CO2排放与人为CO2吸收量之间关系进行调整和平衡的过程;其内部由宏观、中观和微观三层结构组成,每层结构各不相同。多阶段混合主导型碳中和实现模式的提出,拓展和完善了气候变化整体治理理论,为气候变化治理提供了机制借鉴。  相似文献   
2.
运用参与性诊断(即PRRA)方法对临安示范林地区的森林经营主要政策进行了诊断分析,找出了现行政策存在的问题,如:政策环境欠佳,产权政策不到位,税费政策不合理,林业产品生产、加工和销售脱节,森林生态效益补偿政策欠规范、不合理等.同时,运用参与性设计的方法对若干主要政策进行专项设计,并在此基础上,从优化森林可持续经营的政策环境和规范政策系统运行两方面入手,提出一套科学、合理和有效的适合当地水平的森林可持续经营综合设计方案,以促进示范林网络的发展.  相似文献   
3.
对林业税费的经济学分析   总被引:3,自引:0,他引:3  
该文运用经济学的基本工具———供给和需求曲线 ,以商品林为研究对象 ,探讨了林业税费的作用机理和内涵。该文认为商品林生产具有正的外部性 ,市场失灵使生产者将不能提供社会真正所需要的商品林数量。在封闭的市场条件下 ,林业税费会直接成为价格的一部分 ,商品林生产者应当能够获得正常利润 ,与税费高低无关 ,但会使一部分林地退出生产。林业补贴是一种负的林业税收。在开放市场经济条件下 ,国内商品林供应量低于没有林业税收时的商品林供应量 ,更低于考虑社会生态需求时的商品林供应量 ,造成巨大的社会福利损失 ,应减免林业税费、增加林业扶持、取消价格管制。该文进一步研究了与林业税费密切相关的森林采伐限额政策 ,认为对商品林应该完全取消采伐限额政策  相似文献   
4.
森林旅游业实施绿色营销的研究   总被引:4,自引:0,他引:4  
深刻分析了传统市场营销策略对森林旅游业所产生的负面影响。阐述了森林旅游业实施绿色营销的基本原则 ,并提出相应的实施对策。这些对策主要包括努力塑造绿色企业形象 ,建立新型的绿色管理模式 ,大力开发森林旅游绿色产品和生态道德建设  相似文献   
5.
Silphids in urban forests: Diversity and function   总被引:2,自引:0,他引:2  
Wolf  Jordan M.  Gibbs  James P. 《Urban Ecosystems》2004,7(4):371-384
Many ecologists have examined the process of how urbanization reduces biological diversity but rarely have its ecological consequences been assessed. We studied forest-dwelling burying beetles (Coleoptera: Silphidae)—a guild of insects that requires carrion to complete their life cycles—along an urban-rural gradient of land use in Maryland. Our objective was to determine how forest fragmentation associated with urbanization affects (1) beetle community diversity and structure and (2) the ecological function provided by these insects, that is, decomposition of vertebrate carcasses. Forest fragmentation strongly reduced burying beetle diversity and abundance, and did so far more pervasively than urbanization of the surrounding landscape. The likelihood that beetles interred experimental baits was a direct, positive function of burying beetle diversity. We conclude that loss of burying beetle diversity resulting from forest fragmentation could have important ecological consequences in urban forests.  相似文献   
6.
提出了非负权最短路问题的一种新算法。与有名的Dijkstra算法相比,这种算法计算简便、容易理解、易于编程。  相似文献   
7.
Rainfall interception by Santa Monica's municipal urban forest   总被引:4,自引:2,他引:2  
Effects of urban forests on rainfall interception and runoff reduction have been conceptualized, but not well quantified. In this study rainfall interception by street and park trees in Santa Monica, California is simulated. A mass and energy balance rainfall interception model is used to simulate rainfall interception processes (e.g., gross precipitation, free throughfall, canopy drip, stemflow, and evaporation). Annual rainfall interception by the 29,299 street and park trees was 193,168 m3 (6.6 m3/tree), or 1.6% of total precipitation. The annual value of avoided stormwater treatment and flood control costs associated with reduced runoff was $110,890 ($3.60/tree). Interception rate varied with tree species and sizes. Rainfall interception ranged from 15.3% (0.8 m3/tree) for a small Jacaranda mimosifolia (3.5 cm diameter at breast height) to 66.5% (20.8 m3/tree) for a mature Tristania conferta (38.1 cm). In a 25-year storm, interception by all street and park trees was 12,139.5 m3 (0.4%), each tree yielding $0.60 (0.4 m3/tree) in avoided flood control costs. Rainfall interception varied seasonally, averaging 14.8% during a 21.7 mm winter storm and 79.5% during a 20.3 mm summer storm for a large, deciduous Platanus acerifolia tree. Effects of differences in temporal precipitation patterns, tree population traits, and pruning practices on interception in Santa Monica, Modesto, and Sacramento, California are described.  相似文献   
8.
公益林补偿政策评价研究   总被引:1,自引:0,他引:1  
论述了公益林补偿政策评价研究的现状,分析了补偿政策评价的特点和存在问题,提出了解决问题的对策,并借鉴了美国联邦政府项目评价体系,提出了补偿政策的定性评价内容。  相似文献   
9.
Under current conditions of accelerated socioenvironmental change in the Mediterranean forested landscapes, fire is one of the most critical and difficult risks to tackle within the region. This article summarizes the lessons learned from a project based on the participatory integration of qualitative local stakeholders' knowledge with expert GIS fire simulations carried out in the County of El Bages, Catalonia, Spain. First, in this article, a theoretical model--the forest fire circle--is presented in order to explain the reasons for the rise in the damage and frequency of forest fires in this Mediterranean area. Second, it describes the methodology developed and the stages followed during the project. Results show that: (1) the advocacy of old forest reactive management paradigm assumptions and practices based on uncontrolled forest succession can put vast wooded areas of the Mediterranean basin at critical risk; and (2) forest fire management approaches that ignore the crucial role of long-term prevention and local capacity building strategies have failed. In the final section, the content and the specific dimensions of the old reactive paradigm that has characterized forest fire risk management in Catalonia are discussed and contrasted with the possibly emerging preventative paradigm.  相似文献   
10.
In this article, I utilize the perspectives of economic sociology to examine the structural background of forest devastation in Japan. First, I explore the factors behind cited problems for the forestry industry and demonstrate that expanded imports of inexpensively priced foreign-sourced logs do not sufficiently explain those issues. On that basis, I then demonstrate that the concepts and analytical tools offered by economic sociology are essential to a full understanding of relevant problems. Next, to understand how the current crisis differs from that experienced by forestry households in the 1980s, I turn my focus to changes in the social networks that supported the trade in wood products. The crisis witnessed a transformation that involved disembedding sawmills from the traditional wood trading networks that had relied on cooperative ties with forestry households. Eventually, social relationships between forestry households and sawmills were severed and these households became unable to address their economic difficulties through their existing practices. Given that context, I then examine the contrasting economic behavior of sawmills and forestry households and demonstrate that exposure to global price competition forced forestry households into uncontrolled over-cutting. Finally, I assert that economic sociology is better able to provide a more precise understanding of the true nature of the problems facing forestry in modern-day Japan than conventional economics with its adherence to the useful but insufficient principles of market competition and economic efficiency.  相似文献   
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