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变化条件下干旱内陆河流域水循环特征研究
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作者 汪世国 《人民黄河》 CAS 北大核心 2011年第9期16-18,共3页
为探索干旱内陆河流域降水稀少、生态环境脆弱、人类长期活动和剧烈气候变化等对流域内水循环产生的影响,以玛纳斯河流域为例,根据天然-人工二元水循环系统理论,建立了二元水循环模型,并对该流域水循环每一环节的蒸发、渗漏进行了计算... 为探索干旱内陆河流域降水稀少、生态环境脆弱、人类长期活动和剧烈气候变化等对流域内水循环产生的影响,以玛纳斯河流域为例,根据天然-人工二元水循环系统理论,建立了二元水循环模型,并对该流域水循环每一环节的蒸发、渗漏进行了计算。结果表明:玛纳斯河流域平原区天然水循环通量为9.38亿m3/a,占流域降水通量的11.70%;人工水循环通量为18.35亿m3/a,占流域降水通量的22.88%;平原区的人工水循环通量已经远远超过了天然水循环通量。玛纳斯河流域总水循环通量为80.26亿m3/a,现状条件下全流域天然水循环通量为61.91亿m3/a,流域天然水循环通量与人工水循环通量的比例为77.14∶22.86。 展开更多
关键词 水循环变异 天然循环通量 人工循环通量 干旱内陆河流域 玛纳斯河流域
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Spatial Variation and Space Optimization of the Development of China’s Circular Economy
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作者 Li Ning 《Chinese Journal of Population,Resources and Environment》 2012年第2期51-59,共9页
China's circular economy is still at the initial stage, whose development has many difficulties and problems requir- ing immediate resolution theoretically and practically. Due to the differences of regions on the sc... China's circular economy is still at the initial stage, whose development has many difficulties and problems requir- ing immediate resolution theoretically and practically. Due to the differences of regions on the scale of land, endowment of resources, economic basis and cultural background, the devel- opmental levels and capabilities of circular economy are inevi- tably different. Based on establishing the indicator system for assessing the developmental level of regional circular economy, spatial variation of China's circular economy is measured by the quantitative measurement using principal component analysis, and the existing problems are also analyzed and discussed. On one hand, the differences of the development capability of the circular economy of different provinces (cities) are profound in China; (!)Difference between the first category (strong) and the second category (relatively strong) is 1.1264 points. Difference between the second category and the third category (relatively weak) is 0.3867 points. Difference between the third category and the fourth category (weak) is 1.0238 points. Differencebetween the tlrst category and the tourtla category reaches up to 2.0869 points. Average difference between the area where the developmental level of circular economy is relatively strong and the area where the developmental level of circular economy is relatively weak is 1.3617 points. (~)The differences of the dis- tribution of the areas, with different development capability of circular economy, which are located in the three economic regions of China, are also profound. The regions with a relatively strong development capability of circular economy are mainly located in the eastern economic area, which account for 22.58% of the whole regions, while only account for 12.90% in the middle and western economic areas. On the contrary, the regions with a relatively weak development capability of circular economy account for 48.39% in the middle and western area, while ac- count for 16.13% in the eastern area. On the other hand, among regions with different development capability of circular econ- omy, the regions with a relatively weak development capability of circular economy are in a dominant position, which accountfor 64.52% of all the provinces (cities), which indicates that the development of the China's circular economy still has a long way to go. Though certain achievements have been made in the development of China's circular economy, in general, there are still some obstacles to be tacked in the development of China's circular economy which require the economic, legal and administrative methods. 展开更多
关键词 circular economy spatial variation space optimiza-tion China
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