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1.
资源依赖型地区产业转型是保障国家资源安全和促进经济社会可持续发展的关键。我国资源依赖型地区数量多且分布广,现阶段此类地区开发阶段不同,所以进行产业转型的路径存在差异,其过程任重而道远。针对我国资源依赖型地区产业发展的现状进行分析并找出其问题,基于此,科学全面的探讨适合此类地区实现产业转型的五个战略,并进一步分别从地区资源开发阶段和地区利益相关主体两个维度,制定出符合资源依赖型地区产业转型的对策。 相似文献
2.
对西部特色农业结构调整的思考 总被引:1,自引:0,他引:1
西部开发战略的重要内容之一,就是开发西部特色农业,而开发西部特色农业首先要搞好农业结构调整.农业结构调整的内容有:农产品品种结构、农业生产内部结构、农产品加工转化增值和食粮主产区域结构的调整.农业结构调整也要注意一些问题,趋利避害,从实际出发,因地因时制宜,把握全局,平稳进行. 相似文献
3.
位山引黄灌区泥沙淤积原因及处理对策 总被引:7,自引:2,他引:5
位山灌区是黄河下游大型引黄灌区 ,渠系泥沙淤积严重 ,泥沙处理困难。通过采用远距离输沙、集中处理沉沙区泥沙、分散沉沙和节水减淤等技术措施 ,减少了渠系的泥沙淤积。对清淤产生的泥沙 ,采取综合开发利用的技术和管理措施 ,取得了比较可靠的效果。 相似文献
4.
三峡库区湖北宜昌、秭归、兴山、巴东四县幅员面积11589.3平方公里,总人口数166.02万人,三峡水库形成后,淹没土面积74.47平方公里,涉及8.94万人,规划农业生产安置2.8万人。本文以四县土地资源利用现状主和环境容量的分析为基础,进行三峡库区移民安置对水土流失的影响评价,论证综合开发利用水土资源,水土保持与开发性移民相结合,是扩大库区人口环境容量的必由之路,研究制订出移民安置与水土资源的 相似文献
5.
Structure and Ordination of Epiphytic Invertebrate Communities of Four Coastal Wetlands in Green Bay,Lake Michigan 总被引:1,自引:0,他引:1
Epiphytic macroinvertebrate communities of four coastal wetlands of Green Bay, Lake Michigan were compared by taxonomic composition, feeding group composition, and environmental influences using Bray-Curtis ordination. Ordination scores from the most sheltered oligotrophic site, Portage Marsh, were distinct from the eutrophic, exposed sites located in middle and lower Green Bay— Seagull Bar, Little Tail Point, and Dead Horse Bay. Epiphyton chlorophyll a, phytoplankton chlorophyll a, and specific conductance strongly correlated to the ordination axes, indicating the trophic gradient within Green Bay was a primary environmental influence. The feeding group compositions at the sites were consistent with the type and abundance of food available. Portage Marsh is a scraper-shredder system, with macroinvertebrates feeding mainly on epiphyton and coarse particulate detritus. Dead Horse Bay and Little Tail Point are collector systems, sustained by phytoplankton and fine particulate organic matter. Seagull Bar is intermediate in trophic position along the ordination axes, but more closely resemble the latter two sites. The type and abundance of food resources available to these invertebrate communities are influenced by wave exposure, light attenuation, nutrient levels, and algae levels of the littoral and pelagial waters. Macroinvertebrate communities were sensitive to shifts in food resources, which generated shifts in trophic structure. 相似文献
6.
Optimal Locations of Groundwater Extractions in Coastal Aquifers 总被引:1,自引:0,他引:1
A regional water supply management model for coastal aquifers was developed. One of its outcomes is the definition of the
optimized locations for groundwater withdrawal. Such a tool permits the analysis of alternative plans for groundwater extraction
and the sustainable use of water resources in a coastal aquifer subject to saltwater intrusion. The principal components are
the evolutionary optimization and the analytical/numerical simulation models. The optimization technique looks for the best
well locations taking into consideration the economic results and the satisfaction of the societal water demand. However these
two concerns are conditioned by trying to control the saltwater intrusion, i.e., preserving the environmental equilibrium.
The simulation model uses the governing mathematical equations for groundwater movement to find the interface between freshwater
and saltwater. Because of the non-linearity in the system and the possibility of a jumping interface, a security distance
was defined. This is a controlling variable which can be set by the decision makers. The model was applied to a typical case
with interesting results. For example, diagrams showing the relationship between the location of the wells and the security
distance(s) are of importance to the managers. It was also crucial to have an understanding of the tradeoffs between groundwater
withdrawals, positions of the wells from the coast line, and the security distance. The model was also applied to a real case
in order to relate the extractions, distances and artificial recharge (not presented in this paper). 相似文献
7.
Thomas M. Burton Craig A. Stricker Donald G. Uzarski 《Lakes & Reservoirs: Research and Management》2002,7(3):255-269
Invertebrate communities from different coastal marsh‐plant communities were compared along wave‐exposure gradients using data from 1994, 1998 and 1999. Data were subjected to correspondence analyses to search for patterns in invertebrate communities in relation to plant‐community structure and wave exposure. In 1994, quantitative plant‐ and sediment‐invertebrate samples were taken from nine habitats: four from inland, subsurface‐connected marshes and five from littoral, emergent marshes. In 1998, sweep‐net samples were taken from 13 plant communities: six on the exposed and seven on the protected side of an island. In 1999, 2–3 plant communities/sites were sampled with sweep nets from four sites around the Bay so that intersite differences between inner, less‐exposed and outer, more‐exposed habitats could be examined. In all three studies, correspondence analyses separated inland, protected or inner sites from littoral, exposed or outer sites, suggesting differences in invertebrate‐community structure. For example, Hydracarina and Asellidae occurred in large numbers in inland sites, but were less common or absent from exposed, littoral sites. Littoral marshes also separated along an exposure gradient with Tanytarsini and Orthocladiinae collectors of organic particles occurring in very high numbers in outer, exposed areas where organic particles from the pelagic zone entered the marsh. Certain plant‐community types clustered together (e.g. wet meadow and Scirpus) while others, such as Typha, stands clustered according to exposure to waves suggesting the importance of both plant‐community structure and wave exposure in determining invertebrate‐community structure. We present a conceptual model that suggests that invertebrates in Great Lakes' marshes are distributed along gradients of decreased mixing of pelagic water and increases in sediment organic matter from outer to inner marsh and between littoral and adjacent inland marshes. Some invertebrates do best on one end of these gradients, while the majority are generalists found across habitat types. 相似文献
8.
Yoshiharu Takamura 《Socio》2003,37(2):85-102
As a national project of Japan, plans for the relocation of several government agencies out of Tokyo have been ongoing. This paper is concerned with the problem of site selection for this project. The National Land Agency, the agency responsible for this project, has declared that the process of site selection should be rational, open to the public and easily understandable. In an effort to meet these requirements, we propose a consensus-making method for reaching a group decision, based on a combination of the analytic hierarchy process (AHP) and the Assurance Region model of data envelopment analysis (DEA). Several strategic uses of these methodologies, e.g., Delphi procedures, are also discussed. Based on these analyses, the “Wise Men” Committee for deciding the best site has chosen two from among ten contenders, one from the North-East and the other from the Central part of Japan, as candidates for the best relocation site. We could not discriminate between the two with respect to the multiple criteria chosen for evaluating sites. The Committee recommended the two sites to the Prime Minister at the end of December 1999. The Prime Minister reported this conclusion to the Diet. This topic is currently the focus of political discussions in the Diet. In this report, the authors summarize the decision-making processes that the Wise Men Committee followed, putting emphasis on the methodological aspects. 相似文献
9.
基于协整分析的东北区域产业结构优化与金融支持关系研究 总被引:1,自引:0,他引:1
基于1978—2003年的统计数据,采用协整关系检验法和格兰杰(Granger)因果检验法对东北地区金融发展与产业结构优化之间的关系进行了实证检验。分析结果表明东北区域产业结构优化与金融发展之间存在长期动态均衡关系及单向因果关系,即金融发展对东北区域产业结构优化具有支持作用,从而为政府经济决策提供了政策依据。 相似文献
10.
文章介绍了外向型经济的概念、内容、类型,分析了中部地区的基本情况及存在的问题,论述了外向型经济对中国中部崛起的影响。 相似文献