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areal differentiation of spermatophytic flora in Henan Province

Journal of Geographical Sciences 2006年第2期16卷 223-230页

作者： ZHANG Guibin Institute of Natural Resources and Environmental Science Research College of Environment and Planning Henan University Kaifeng 475001 China

Henan province, located between 110°21＇E-116°39＇E and 31°23＇N-36°22＇N, stretches from warm-temperate to subtropical transitional zone. Its special position and resultant varied physical conditions, in its long geologic history, give rise to not only a rich but also complex and prominently transitional flora. Therefore, in-depth study of the floristic areal differentiation is of importance to Chinese florilization and in accurately drawing the boundary of warm-temperate and subtropic zones in China. Based on the recent floristic data, this paper conducts comparison and analysis of the floristic difference and resemblance among the Dabie, Tongbai, Funiu and Taihang Mts. in Henan province. The result shows that the Dabie and the Tongbai Mts. have the similar flora components, the northern and the southern slopes of the Funiu Mts. have identical flora, but the Taihang Mts. stand alone in their floristic character. Therefore these mountainous areas should be grouped into three floral regions in China： the Dabie and the Tongbai Mts. belong to East China Floral Region, the Taihang Mts. to North China Floral Region, and the two slopes of the Funiu *** Central China region.

关键词： flora areal differentiation spermatophyte Henan province

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areal differentiation of virtual water for agricultural products and its effect on regional agricultural structure adjustment in China: 1995-2007

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Ecological Economy 2010年第1期6卷 80-87页

作者： QIN Li-jie ZONG Sheng-wei CHANG Yong-zhi College of Urban and Environmental Science. Northeast Normal University Changchun 130024. P. R. China

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.

关键词： Virtual water areal differentiation Adjustment of agricultural structure

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知识经济的地理特征

中国地理

引用

中国地理 1999年第3期 398-400页

作者：张平宇

知识经济作为一种新的地理现象，它将引起传统地理空间概念的变化。知识经济具有一定的区位趋向性，并在宏观、中微观地域层次上都将展现出明显的地域分异特征。不同于传统的农业经济和工业经济，知识经济的空间组织亦具有新的特点。

关键词：知识经济地域分异空间组织 Knowledge economy areal differentiation spatial organization

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