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331.
PRED问题与地理工程   总被引:1,自引:0,他引:1  
本文首先定义了由人口、资源、环境和发展构成的PRED问题的思路,讨论了它的性质;然后提出用地理工程解决PRED问题,并构建了地理工程的理论框架。  相似文献   
332.
详细讨论了卫星遥感技术在长江流域水资源管理方面的应用问题,提出了两种实用的方法:①卫星遥感技术在灌溉水资源管理方面的应用;②长江流域地下水、地表水资源估算。进一步分析了两种方法的特点,介绍了卫星遥感技术的优点及用途,建议在长江流域水资源管理中加以利用。  相似文献   
333.
农业生产地域分工与农产品专业化生产是使农业从自然经济阶段向以市场为导向的商品农产品生产转变的一个标志。本文在分析该区农业布局现状及其存在问题的基础上,提出了农业总体布局的设想与不同类型地域农业开发的主攻方向与对策,并对市场经济体制下粮食、棉花、猪、禽、水产品等农产品生产基地的地域选择、建设规模与技术措施等进行了探讨。  相似文献   
334.
该模型具有长期经济协调预测、优化和模拟的功能,它将国民经济分为16个部门,充分考虑了影响国民经济各部门变化的主要因素,在供需、资金、流入流出、水资源、环境等均衡约束条件下,以 1990年不变价格,采用线性规划方法,逐年滚动优化预测了1991~2020年烟台市国民经济发展的趋势、产业结构和规模等各项指标。  相似文献   
335.
中国的人口,资源,环境问题及若干战略选择   总被引:3,自引:0,他引:3  
中国具有十分特殊的基本国情,如何根据中国的国情以及特定的历史与现实条件,选择适宜的组织机制,实施正确的长期发展战略,加速中国的现代化进程,这是一个十分紧迫而又令人关注的重大课题。本文主要从人口、资源、环境等方面分析中国现代化所面临的困境,以及应采取的战略选择。  相似文献   
336.
湖北野生食果资源特点及其开发途径   总被引:2,自引:0,他引:2  
野生食果为营养丰富的食用资源植物。在深入调查的基础上,分析了湖北野生食果资源的特点,提出了野生食果资源开发的对策以及产品深加工的途径,为野生食果资源的开发利用打下了坚实的基础。  相似文献   
337.
Polybrominated diphenyl ether in the East Asian environment: a critical review   总被引:20,自引:0,他引:20  
Polybrominated diphenyl ethers (PBDEs) have been extensively used as flame retardants in consumer goods. Sufficient evidence shows that PBDEs have been rapidly accumulating in the environment worldwide. In Asia, deca-bromodiphenyl ether has been produced and used in large quantities, while penta-BDE has largely ceased in the mid-1990s. This paper summarizes and critically reviews the status of PBDE pollution in East Asia, with emphases on the comparisons with Europe and North America and the interpretation of the differences. In general, the concentrations of PBDEs in atmosphere, sludge, human and biological samples of East Asia are comparable to or lower than those in Europe and North America. However, in the sediments of waters near densely populated and heavily industrialized areas, PBDE levels are among the highest ever reported in the literature. In Japan and China, concentrations of PBDEs in sediment cores showed an increasing trend for the past 20-30 years. Also, PBDEs levels in human breast milk in Japan increased about 10-fold in the past 20 years. The presence of PBDEs in fur seal has increased about 150-fold in 1994 than that in 1972. Regional and inter-continental transport cannot be confirmed due to insufficient information. However, the detection of a number of PBDE congeners in a pristine lake on the Qinghai-Tibet Plateau may be an evidence of their long-range transport.  相似文献   
338.
Sustainable development requires enriching and developing the traditional international trade theory, especially integrating the environmental elements into the current analysis framework of relative comparative advantages. These relationships among labor, capital, and environmental resources are analyzed in this study, using the relative comparative advantages method. As indicated in the analysis, the ever-increasing international trading volume in China relies not only on the relative comparative advantage of labor but also on the environmental one; these are the two major advantages in China. However, the two advantages will experience serious challenge in the future along with a rising cost on labor and environmental pollution.  相似文献   
339.
Urban agglomeration of the Yangtze Delta (UAYD), one of the most developed regions of China, has witnessed an increasing prevalence in building ecological cities when the ecological cities are pursued by many modem cities, and great achievements have been made in this regard. It is inevitable, however, that certain problems exist during the construction of ecological city, which include but not limited to non-harmonious development of urban complex ecosystem, and the difficulty in quantifying eco-city construction or incomplete quantification in assessing the construction of present and future eco-city. Based on the analysis on social-economic conditions and regional conditions of the UAYD, this paper attempts to set up an index system of eco-cities combining with local characteristics, and to adopt the indices of eco-city, urban harmony, and eco-city colligate to evaluate the ecological level, urban harmonious development and eco-city construction of cities within the UAYD. Results indicate that among 15 cities in UAYD, Suzhou City ranks the highest in terms of eco-city construction, whereas Nantong ranks relatively lower; sustainable eco-city construction is possible only when cities are developed in every respect of harmony.  相似文献   
340.
The article studies tourism eco-environment of 14 cities of Gangsu Province, China, based on GIS with many kinds of multi-subject spatial database, such as remote sensing data, observation data and literature data. The research results were as follows. First, spatial features of 14 cities' tourism eco-environment are displayed with five levels of vulnerability respectively. The vulnerability in Gansu becomes worse from Gannan City, located in southern Gansu to Hexi Corridor which lies in northwestern Gansu. Second, the areas of above the middle vulnerability level make up 75% of the total areas of Gansu Province. Third, more than 70% of high-level human and natural tourism resources are in the areas with high vulnerability eco-environment. Fourth, it is crucial to develop comprehensive tourism industry in order to improve the harmonious development between tourism industry and eco-environment in Gansu Province.  相似文献   
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