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21.
Convergence or divergence in desertification risk? Scale-based assessment and policy implications in a Mediterranean country 总被引:1,自引:0,他引:1
This paper explores changes (1990–2000) in two environmental indexes with the aim of providing empirical evidence on regional and local convergence in an increasing-impact phenomenon such as Land Degradation (LD) in Italy. Convergence analysis for ESAI (Environmental Sensitive Area Index) and LVI (Land Vulnerability Index) was developed at five different geographical scales. Results indicate that territorial disparities in land vulnerability tend to increase during the investigated period following a defined spatial pattern that depends on land quality, the environmental context and the economic performance of regional systems. Finally, the implications this process has on policy strategies aimed at mitigating desertification risk are discussed. 相似文献
22.
西部大开发十五年环境效率评价及其影响因素分析 总被引:1,自引:0,他引:1
西部大开发政策实施以来,西部地区实现了快于东部和中部的经济增长。正确认识西部地区经济增长中的环境成本,评价西部地区的环境效率具有重要意义。本文运用考虑非期望产出的超效率SBM模型测算了2000—2014年西部大开发以来的环境效率。研究发现:西部地区环境效率偏低,处于相对无效状态。西部地区环境效率明显低于传统效率,经济增长付出了较高的环境代价。西部大开发以来传统效率与环境效率之间的差距呈现先扩大后缩小的"倒U"型走势变化。西部地区省份环境效率在全国排名靠后,各省份的环境效率呈现出差异化的发展态势,其中重庆和四川排名不断提升,新疆排名逐步回落,内蒙古和广西在西部地区排名相对靠前且比较稳定,云南和陕西一直处于中间水平,贵州、甘肃、青海、宁夏排名相对靠后。西部地区环境效率2000—2003年上升,2004—2010年不断下降,2010—2014年趋于平稳。西部地区环境效率低于东部地区且差距大,也低于中部地区和全国平均水平。通过收敛性检验发现,西部地区各省份间的环境效率差距呈现先缩小后扩大的趋势;西部地区与东部地区间的环境效率差距逐渐扩大,与中部地区间的环境效率差距先扩大后缩小。本文同时采用了Tobit模型进行面板回归,实证分析了西部地区环境效率的影响因素。结果表明:经济发展水平、科学技术水平、能源消费结构、环保投资力度对西部地区环境效率具有显著影响;产业结构变化和对外开放程度对西部地区环境效率影响不显著;西部地区存在环境效率的库兹涅茨曲线。 相似文献
23.
湘西民族文化产业发展对策研究 总被引:1,自引:0,他引:1
民族文化产业是文化产业发展中一个重要组成部分,是充分利用当地富有特色的民族文化资源,促进本地区经济社会文化协调发展的一个重要途径。以湘西自治州民族文化产业为研究对象,通过实地调查,分析了湘西民族文化产业发展中存在的问题,提出了湘西民族文化产业的发展对策。 相似文献
24.
Denis Gingras Kaz Adamowski Paul J. Pilon 《Journal of the American Water Resources Association》1994,30(1):55-67
ABSTRACT: When nonparametric frequency analysis was performed on 183 stations from Ontario and Quebec, unimodal and multimodal maximum annual flood density functions were discovered. In order to determine generating mechanisms, a monthly partitioning of the annual maximum floods was undertaken. The timing of the floods revealed that the unimodal distributions reflected a single flood generating mechanism while the multi-modal densities reflected two or more mechanisms. Based on the division of the flood series by mechanisms, nine homogeneous regions were delineated. L-moment distributional homogeneity tests along with smaller standard errors for the regional equations supported the delineation. 相似文献
25.
26.
Gary D. Tasker 《Journal of the American Water Resources Association》1982,18(6):965-970
ABSTRACT: Data splitting is used to compare methods of determining “homogeneous” hydrologic regions. The methods compared use cluster analysis based on similarity of hydrologic characteristics or similarity of characteristics of a stream's drainage basin. Data for 221 stations in Arizona are used to show that the methods, which are a modification of DeCoursey's scheme for defining regions, improve the fit of estimation data to the model, but that is is necessary to have an independent measure of predictive accuracy, such as that provided by data splitting, to demonstrate improved predictive accuracy. The methods used the complete linkage algorithm for cluster analysis and computed weighted average estimates of hydrologic characteristics at ungaged sites. 相似文献
27.
Tiziano Gomiero Davide Pettenella Giang Phan Trieu Maurizio G. Paoletti 《Environment, Development and Sustainability》2000,2(2):119-142
Vietnam, in the ongoing transition to market economies, has to cope with high rural poverty and a dramatic process of forest loss and environment degradation, particularly in the mountainous regions. The government considers rural poverty as the main cause of environment degradation, associated with slash-and-burn cultivation and to an unclear definition of property rights on forest land. In 1993, the government launched a Forest Land Allocation programme aiming to lease forest lands to individual households and, on this basis, to solve food security problems, halt the increasing environment degradation and preserve the remaining forests.To evaluate the results of this land reform policy, two upland pilot communes have been intensively monitored. The environmental and economic impacts of the forest land reform allocation in the two study areas are presented, after providing a background on the Vietnamese situation of mountain zones. On the basis of these findings, it is discussed as to whether the current forest land allocation process may actually promote local development and natural resources conservation, and under what conditions. Deforestation problems must be tackled also with new macroeconomic policies (e.g. credit programmes to support sustainable agriculture practices) and social policy (e.g. reduction of demographic pressure), together with the reform of the State institutions (e.g. State Forest Enterprises) involved in management of the forest areas. 相似文献
28.
29.
Cai Kui Du Juan Dai Cong Hu Huabin . Center for Rural Development Studies Yunnan University Kunming Yunnan China . Institute of Ethnology Yunnan Academy of Social Science Kunming Yunnan China . Institute of Economics Yunnan Academy of Social Science Kunming Yunnan China . Xishuangbanna Tropical Botany Garden Chinese Academy of Sciences Kunming Yunan China 《中国人口.资源与环境(英文版)》2007,5(2):78-83
A three-year study over the Bai, Jingpo and Huayaodai communities in Yunnan Province reveals that the community development is significantly influenced in various ways by such cultural factors as the concepts of development; concepts and traditions of inter-community relationships, consumption, mar- riage and gender; patterns of decision-making and production, resource and income allocation; as well as the role of information dissemination systems, religion and ritual. Based on the analysis over the interactive relevance between each factor and community development, some strategies and methods for dealing with such a cultural relevance in development projects are recommended. 相似文献
30.
发达与欠发达地区耕地保护行为中的利益机制分析 总被引:6,自引:0,他引:6
俞文华 《中国人口.资源与环境》1997,7(4):22-27
本文从当前发达与欠发达地区耕地保护上的利益矛盾入手,以它们之间的内在经济关系为基础,运用局部均衡分析方法,构建了一个简单的经济模型,对上述矛盾“零和博弈”的长期效应进行了揭示,并讨论了消除这种不良影响的政策或制度安排。 相似文献