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81.
以衡阳紫色土丘陵坡地为例,通过总结前人的研究成果和采集湖南环境生物职业技术学院生态研究所紫色土生态实验站部分收集整理和试验数据,从全局性、紧迫性、高效性、层次性、可持续性、创新性与多样性的角度提出了在衡阳紫色土丘陵坡地的急坡地、陡坡地、缓陡坡地其水土保持生态经济型植被恢复模式分别采用三种典型模式,即灌草模式、乔灌草模式与林果模式,以期促进该区域的生态、经济与社会的全面协调与可持续发展。 相似文献
82.
谢谦 《湖南经济管理干部学院学报》2012,(3):103-105
都市产业园是我国产业经济发展的重要方式,与城市建设密切相关,是集生产、流通、消费为一体的综合性产业园区,具有资源丰富、空间集约等多个特征。岳麓科技产业园位于长沙市岳麓区,园区发展尚处于起步阶段,存在着资源、企业、设施等多方面的制约因素。以"753"战略为核心,走以聪明增长、高新技术、国际化建设为特征的发展道路,才能促使园区稳定迅速的发展。 相似文献
83.
With a vast territory, the space-time distribution of water resources is uneven in China. There is a great dif ference in natural conditions and farmland management of agricuttural production in different regions. The areal differentiation of agricultural products virtual water is obvious. Comparison with the agricultural products virtual water from 1995 to 2007 in China shows an increase in the first ten vears and a little decrease in recent years. There has been a tendency of increase all the time in Northeast and Northwest. but a decrease after an increase firstly in other regions. The virtual water offood crops is the maximum which accounts for more than 70% in China. and that of vegetables is in a fast growth. The proportion of agricultural products virtual water to the total water resources in each region has a large difference, showing the imbalance of agricultural water in different regions, which accounts for 50%-90% in Northeast, and 125%-185% in North China. Under the guidance of virtual water strategy, based on the differences of resource endowment, each region should adjust agricultural structure, decide production by water, and select water suitable crops. In water-rich region, agricultural produets of high water consumption should be planted appropriately, which will make full use of the abundant local water resources. In water-shortage region the crop production of high water consumption and low efficiency should be depressed, and that of low water consumption and high efficiency should be supported and increased. It will achieve reasonable disposition of water resources, promote ecological restoration and environmental protection, as welt as ensure food security. 相似文献
84.
国外水资源管理模式对湘江水资源统一管理与调配的借鉴 总被引:1,自引:0,他引:1
在城市化进程加速,流域人口不断增加并向沿岸城市迅速集中的背景下,湘江水资源管理存在"条块分割、部门分割"的问题,管理成本高、效率低。借鉴国外水资源管理的经验,建立健全水资源管理法律机制,对湘江水资源实行统一管理和统一调配,以提高管理效率,实现水资源公平配置,为长株潭两型社会建设提供保障。 相似文献
85.
This paper suggests an application of an averting behaviormethod to reconcile inconsistent public activity with objectiveenvironmental risk. In Korea, an historically polluted watersupply has created citizen resistance to using tap water. Koreansperceive low quality levels for tap water, although objectivelymeasured data show that the pollution levels are lower than theacceptable risk. We hypothesized that the irrational aversion tousing tap water is a consequence of inconsistencies between theobjectively measured and perceived pollution levels. We introducethe perception averting behavior method, in which we add aperception measure unit to the conventional averting behaviormethod. We found that the perception measure provided a validexplanation for citizens' aversion to using tap water in Korea. 相似文献
86.
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88.
Water's role in manufacturing technologies has received limited attention. A KLEM model of the sector's technology is extended to include two facets of water use: intake and recirculation. Three annual cross-sectional surveys on plant-level water use are pooled and combined with census data to estimate this extended model for the Canadian manufacturing sector over the period 1981–1991. While Canada's water allocation regulations influence private water withdrawals, statistical tests support representing water intake as a variable input. Water intake is found to be a substitute for water recirculation, energy, labour and capital. The relationship between water intake and recirculation is stronger when water intake is process-related rather than related to cooling and steam production. Technological change has been biased in the direction of increased water intake and decreased water recirculation. 相似文献
89.
Agricultural impacts on water quality and implications for virtual water trading decisions 总被引:2,自引:0,他引:2
Research on the flow of virtual water associated with agricultural crop production and trade has focussed almost entirely on water quantity. It is pertinent to consider and quantify the opportunity costs in terms of reduced water quality associated with crop production. This paper investigates the impacts of water quality on virtual water trading by creating a proxy for water quality impacts by calculating the amount of water required to dilute nonpoint-source agrochemical inputs to relevant water quality guideline values. The quantity of water required for dilution of five agrochemicals (two nutrients; nitrogen and phosphorus and three insecticides; azinphos-methyl, chlorpyrifos and endosulfan) was estimated for five crops in South Africa (maize, wheat, sugar cane, citrus and cotton) and compared to consumption of irrigation water (blue water) and rainfall (green water) for the same crops. Results indicate that the volume of water required for dilution is similar to the total sum of green and blue water required for crop production, but significantly greater than blue water use (irrigation use). For all crops phosphorus losses require greater amounts of water for dilution than for nitrogen, while pesticides result in the greatest water quality use. Estimates of water quality use are based on assumptions for a number of input variables (i.e. fertilizer application rates, percentage loss of agrochemicals from cropped areas). A Monte Carlo analysis (5000 iterations) was run to randomly select input variables from within defined ranges. Water quality use was calculated and expressed as a factor of blue water use. For all crops the average factor indicated that the volume of water required for dilution of all agrochemicals was greater than that required for irrigation. The results of this study clearly indicate that the impacts of agriculture on water quality need to be considered in virtual water trading scenarios. The incorporation of a method to predict impacts on water quality provides a comparative tool which generates a more holistic frame of reference for decision making with regard to impacts on the water resource and virtual water trading. 相似文献
90.
王文浩 《生态经济(学术版)》2009,(2):375-377
甘南黄河重要水源补给生态功能区地处青藏高原东北边缘,是内地通向藏区的门户。保护与建设这一区域的生态环境,不仅对黄河中下游地区广大人民群众的生产生活、维护国家生态安全具有重要意义,而且对加强民族团结、维护祖国统一,促进各民族的共同发展具有重要意义,文中分析了甘南黄河重要水源补给区生态环境问题,提出了改善对策。 相似文献