陕西省农产品虚拟水的时空变异分析

本文提出了虚拟水指数的概念,制定了等级划分标准,并对陕西省1989~2004年的虚拟水含量进行了时空变异分析。结果表明:1989年陕西省生产家产品的虚拟水含量可分为3级:(1)较低水平的区域,包括西安市、咸阳市、渭南市和安康市;(2)稍低水平的区域,包括榆林市、延安市、宝鸡市和商洛市;(3)中下水平的区域,包括汉中市和铜川市;2004年可分为5级:(1)中下水平的区域,包括西安市;(2)中上水平的区域,包括铜川市、汉中市和安康市;(3)稍高水平的区域,包括商洛市;(4)较高水平的区域,包括宝鸡市、渭南市和延安市;(5)很高水平的区域,包括榆林市和咸阳市。可见近16年来陕西省各地市生产家产品的虚拟水含量呈增长趋势,其中变化量最大的是榆林市,其次是延安市和咸阳市,而增长最少的是西安市和汉中市。1989~2004年陕西省居民的人均年农产品消费虚拟水含量是农村高于城镇居民,且有逐年降低的趋势。

Analysis on the Spatial and Temporal Variety of Virtual Water of Agricultural Products in Shaanxi

In this paper,the index of virtual water was proposed and the criterion of evaluation grade was formulated.The spatial and temporal variation of virtual water was analyzed from 1989 to 2004 in Shaanxi Province.The results showed that the index of virtual water in 1989 could be divided into 3 levels :(1) Lower level regions,including Xi'an,Xianyang,Weinan and Ankang;(2) Slightly low level regions,including Shangluo;(3) Medium below level regions,including Hanzhong and Tongchuan.The index of virtual water in 2004 could be divided into 5 levels,which almost were in the medium or high level:(1) Medium below level regions,including Xi'an;(2) Medium above level regions,including Tongchuan,Hanzhong and Ankang;(3) Slightly high level regions,including Yulin,Yan'an,Baoji and Shangluo;(4) Quite high level regions,including Baoji,Weinan and Yan'an;(5) Very high level regions,including Yulin and Yan'an.In short,the indexes of virtual water in regional cities of Shaanxi Province had increased in the past 16 years;The region that the quantity of virtual water increased mostly was Yulin City,secondly ones were Xianyang and Yan'an,and the least ones were Hanzhong and Xi'an.