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101.
Ecotourism in private reserves combines the establishment of protected areas with an incentive mechanism to conserve biodiversity. Brazil's private reserve system is well-established but little is known about its links to tourism. This study puts the global private protected area into context and quantifies the extent to which ecotourism has been adopted as a sustainable land-use practice on private reserves in Brazil. Our findings demonstrate that small reserves do contribute to conservation and are used for ecotourism. The belief that large reserves are necessary for ecotourism and conservation is challenged. Only 4% (n = 45) of the 1182 reserves are engaged in ecotourism, mainly those within the Atlantic Forest biome and these are generally small in size (<50 ha). Reserves provide modest to basic accommodation as well as education and economic opportunities that include adjacent communities. Hiking and bird watching are the most popular activities but many reserves are threatened by poaching and invasive species. The low adoption of ecotourism appears due to a combination of factors, including lack of landowner interest, constraints imposed by regulations, logistics and anthropogenic threats. Nonetheless, there is potential to expand ecotourism within private reserves as 143 further private reserves are located near those already engaged in ecotourism.  相似文献   
102.
This paper presents a free available dataset, the CORINE land cover that helps dealing with the biases caused by pre-defined and heterogeneous census district boundaries in airport catchment area analysis in Europe. Using this dataset and a conventional GIS software it is possible to measure the size of the population within catchment areas at the same spatial level for all EU airports, allowing for consistent comparisons among airports. To illustrate the potential of the CORINE/GIS approach, the size of the population in the catchment areas of all European airports was determined. The empirical exercise has an aggregate perspective, but this database presents many other possibilities of analysis to perform in a case-by-case basis.  相似文献   
103.
本文通过对房地产面积测绘内容的分析,提出了相关的优化房地产面积测绘的措施及其质量管理。  相似文献   
104.
In this paper we derive a series expansion for the price of a continuously sampled arithmetic Asian option in the Black–Scholes setting. The expansion is based on polynomials that are orthogonal with respect to the log-normal distribution. All terms in the series are fully explicit and no numerical integration nor any special functions are involved. We provide sufficient conditions to guarantee convergence of the series. The moment indeterminacy of the log-normal distribution introduces an asymptotic bias in the series, however we show numerically that the bias can safely be ignored in practice.  相似文献   
105.
作为提高农业生产效率、改善农民生活质量及促进农村经济增长的重要物质基础,农村基础设施建设对扩大农村地区内需增长点,解决农村剩余劳动力就业问题以及全面推进城乡统筹发展具有至关重要的意义。广东省作为我国南部地区经济发达省份,具有丰富的农业生产自然资源,但其农村基础设施发展程度相对来说却比较低,其成为农村经济发展的"瓶颈",不利于农村经济结构优化升级。为了保障农村基础设施的供给与农村经济发展水平保持协调一致,文章以广东地区农村为例,采用多元非线性回归分析的方法,在论证农村基础设施建设对农村经济增长的作用机制的基础上,从农村基础设施建设与农业生产、非农生产和农民人均纯收入3方面的内在关系进行计量分析,结果表明,首先农村基础设施对影响农业经济增长的3方面因素都发挥了显著的规模经济效益;其次农村基础设施建设中的教育变量对农业经济增长的作用最为显著;再次,农业机械设施在农业生产中的作用相对于其他影响因素而言不太显著;最后,道路、通讯设施对非农生产和农民人均收入收入的贡献率相对其他变量数值较低。并提出健全农村基础设施建设投融资机制、加大农村基础设施的资金投入力度、提高农村基础设施建设和利用水平、全面推进农村基础设施建设进程等优化策略。  相似文献   
106.
随着近年来党和国家对自然保护区的建设情况的高度重视,自然保护区的规划与管理成为了工作的重中之重。合理高效的方法将直接切实影响到自然保护区的规划、管理、建设,直接影响自然保护区相关相关工作的进展落实情况。自然保护区以它特有的巨大的生态价值和环境效应成为了国内外重点研究的对象,本文就龙凤自然保护区简析国内自然保护区的规划与管理,针对国内外现状进行分析,找出不足和存在的问题,结合实际情况,提出建议和可行性高的解决方案。  相似文献   
107.
通过实地调查研究,借鉴已发布的国际、国家、地区、经营单位层面森林可持续经营标准和指标,以森林可持续经营为主要内容,对亚热带地区国有林场森林经营、人力资源、社会资源等方面进行研究,构建出亚热带地区国有林场可持续经营指标体系,为亚热带地区国有林场可持续经营提供理论借鉴,期盼为制定亚热带地区森林可持续经营指标提供借鉴。  相似文献   
108.
Sovereign risk premia in several euro area countries have risen markedly since 2008, driving up credit spreads in the private sector as well. We propose a New Keynesian model of a two-region monetary union that accounts for this “sovereign risk channel.” The model is calibrated to the euro area as of mid-2012. We show that a combination of sovereign risk in one region and strongly procyclical fiscal policy at the aggregate level exacerbates the risk of belief-driven deflationary downturns. The model provides an argument in favor of coordinated, asymmetric fiscal stances as a way to prevent self-fulfilling debt crises.  相似文献   
109.
利用区位商、EG指数等集聚测度指数对兰州市服务业中的批发业和零售业进行实证分析,得出兰州市的零售业和批发业在大都市内的集中度相对较高,且集聚程度不断增强。  相似文献   
110.
By making use of a gravity model, this paper examines the impact of FDI on exports, imports and net export of Vietnam. The empirical analysis presented in this paper is based on a recently released panel dataset involving Vietnam's 19 major trading partners for the period 1990-2007. The paper also considers the impact of FDI on trade during three sub-periods: the pre-Asian financial crisis, the post-Asian financial crisis and during the Asian financial crisis period. The empirical analysis reveals that a complementary relationship exists between FDI and exports and FDI and imports. While the impact of FDI on net-exports is insignificant during the full sample period, a significant positive relationship exists between net-exports and FDI in the post-Asian financial crisis period.  相似文献   
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