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排序方式: 共有1797条查询结果,搜索用时 46 毫秒
131.
Chen Xuebin 《中国人口.资源与环境(英文版)》2011,9(2)
During the 11^th Five Year Plan period, China improved its policy system for the overall strategy of regional development, and established and completed the policies intended for the promotion of regional cooperation and interaction. Thereupon, regional development in China took on a series of positive changes such as the enhancement of coordination. During the 12^th Five Year Plan period, China will fully implement and continuously improve the policy measures for development in its four major regions, strengthen differentiated guidance to different regions in line with the planning for major function-oriented zones, and accelerate the establishment of basic systems that facilitate coordinated regional development. 相似文献
132.
A major bottleneck for data-based policy making is that data sources are collected, managed, and distributed by different institutions, residing in different locations, resulting in conceptual and practical problems. The use of dispersed data for agricultural systems research requires the integration of data sources, which means to ensure consistency in data interpretations, units, spatial and temporal scales, to respect legal regulations of privacy, ownership and copyright, and to enable easy dissemination of data. This paper describes the SEAMLESS integrated database on European agricultural systems. It contains data on cropping patterns, production, farm structural data, soil and climate conditions, current agricultural management and policy information. To arrive at one integrated database, a shared ontology was developed according to a collaborative process, which facilitates interdisciplinary research. The paper details this process, which can be re-used in other research projects for integrating data sources. 相似文献
133.
ABSTRACT: A procedure of estimating instantaneous flood flows for various return periods on the Island of Newfoundland is presented. The procedure is based on annual maximum instantaneous flows rather than annual maximum daily-mean flows, as the latter requires the conversion of estimated daily-mean flows into instantaneous flows. Regression equations were developed for each of three homogeneous regions for the desired return periods. The flood flow estimation capability of the presented procedure is demonstrated to be better than any other currently available procedure on the Island. 相似文献
134.
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
135.
Berton L. Lamb 《Journal of the American Water Resources Association》1986,22(5):811-815
ABSTRACT: Water resource scientists face complex tasks in evaluating aspects of water projects, but relatively few assessment procedures have been applied and accepted as standard applications. Decision-makers often rely on environmental assessments to evaluate the value and operation of projects. There is often confusion about scientists' role in policy decisions. The scientist can affect policy-making as an expert withess, an advocate or a surrogate. By understanding the policy process, scientists can make their work more “policy relevant.” Using the Terror Lake hydro project in Alaska as a guide, three lessons are discussed: (1) not all problems are able to be solved with technology; (2) policy-relevant technology is rarely imposed on a problem; and (3) the scientist need not just react to the policy process, but can have an impact on how that process unfolds. 相似文献
136.
论区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位 总被引:3,自引:0,他引:3
回顾了国内外区域开发环境管理的发展历程,简要论述了区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位以及两者的相互关系。 相似文献
137.
Thomas R. Harris Chauncey T. K. Ching 《Journal of the American Water Resources Association》1983,19(2):205-210
ABSTRACT: Tradeoffs between regional economic development and resource use is a question often confronting local decisionmakers. A resource-interindustry model can be used to depict the interrelationships between regional economic sectors as to household income and/or employment and resource use. A resource-interindustry model was developed for Humboldt and Lander Counties in Nevada which shows the tradeoffs between regional household income (wages, salaries, profits, and rents) and/or employment and water usage. Water income and water employment multipliers can be ranked, enabling decisionmakers to realize sectors which require greatest regional water usage to regional household income and/or employment. 相似文献
138.
通过对普栉鰕虎鱼的生物学研究和资源现状分析,从做好资源评估,完善管理制度;加强水质监测,保护生态环境;改善繁殖场所,实现人工增殖;加强放流研究,实行规模生产等环节对其资源开发提出了可行性的对策,这对维护生物多样性,将地方特色资源优势持续、有效地转变为经济优势具有重要意义。 相似文献
139.
矿产资源经济区划的理论与方法 总被引:2,自引:0,他引:2
矿产资源经济区划是保护与合理开发利用矿产资源、实现资源优化配置和区域经济可持续发展的基础。本文依据经典的区位理论和地域分工理论,应用系统分析的方法,建立了矿产资源经济区划的一般程序,并归纳了定量分析中必要的技术手段和方法路线。 相似文献
140.
以地市州为基本经济单元,以1999年主要相对指标为依据,通过综合值测算法,将全省划分为四类经济发展水平不同的地区,对四类地区平均总量指标、相对指标进行了对比分析,并揭示了其空间分布特征,简要分析了各类地区经济发展的条件和方向;以1999年、1978年各地市州GDP为例,对比分析了四川省区域经济不平衡发展的动态性特征。 相似文献