Off In Regional Water Resources Carrying Capacity Evaluation Of Temporal And Spatial Differences

As one of fundamental research subject in the study of sustainable development and safety strategy, bearing force of water resource has already aroused the high attention of academic circle and become a focus and hot spot in the science field of water resource at present since it was proposed by the researchers in our country during 1980s. The traditional mode of exploitation and utilization resulted in the increasingly poverty of water resource and the contamination of water environment and a series of other important problems. This severe reality has restricted the development of social economy, affected social stability and threatened the survival of human beings. Because of the crucial role of water resource in the development of social economy, in recent years, "using water resource to decide the production, using water resource to decide the development" is brought forward, that is to say, the bearing force of water resource has become widely concerned.In this paper, the author puts forward the load index of water resource and the concept of carrying index and mode based on water- human beings relationship, according which, load index, carrying capacity and carrying index of water resource in Guanzhong region are calculated, and time- space difference of carrying capacity of water resource in this area is analyzed. Based on load index of water resource and human beings- water balance relation, population overloading district, human beings- water balance district and water volume abundance district are divided separately on the scale of district, city region and county region. This result has enriched the research theory of evaluation on carrying capacity of water resource. At the same time it is significant for the reasonable exploitation and utilization of water resource in Guanzhong region and exploration on the road of sustainable use of water in the whole province scientifically, safely and reliably facing the 21^st century. It is also of great meaning to ensure the sustainable development of the social economy of the whole province in the new century.Through deep, scientific and comprehensive research, the following important results and conclusions are obtained:(1) The potentiality of Water resources' development and utilization in Guanzhong region.On district scale, 1997-2006 water resource carrying indexes in Guanzhong region are all above 10, being I grade. The utilization degree is very high; development potentiality is very small; development conditions are really difficult, and external basin water transfer is need if conditions are allowed. On city region scale, water resource carrying indexes of five prefecturals and municipals in Guanzhong region in 1997, 2001 and 2006 are all I grade. The utilization degree is high; development potentiality is very small; and external basin water transfer is needed to relieve the pressure of water resource if conditions are allowed. On county region scale, in 1997, of 43 jurisdictional districts and counties in Guanzhong region, there are 34 districts and counties whose water resource carrying indexes are I grade, 6 districts and counties are II grade, 2 are III grade and 1 is IV grade. In 2001, there are 35 districts and counties whose water resource carrying indexes belong to I grade, 2 districts and counties belong to II grade, 4 belong to III grade and 2 belong to V grade. In 2006, there are 36 districts and counties whose water resource carrying indexes belong to I grade, 3 districts and counties belong to II grade, 3 belong to III grade and 1 belongs to V grade. The potentiality of water resource in Guanzhong region is of distinct regional nature, utilization degree is relatively high and development potentiality is relatively small.(2) Water resource carrying capacity in Guanzhong region.On district scale, 1997 -2006 water resource carrying indexes in Guanzhong region are between 1.76-4.90, among which, water resource in 2003 is overloading, the in other years, water resource is excess loading. On city region scale, water resource carrying index of prefecturals and municipals in Guanzhong region in 1997, 2001 and 2006 are all above 1.33, all of which are overloading area, and the ration of overloading population is over 33%. Among these, 1997-2006 water resource in Xi'an city is overloading, and Xianyang city is severely overloading, Baoji city dropped from excess loading to overloading, and Tongchuan city and Weinan city are both dropped from severely overloading to excess loading. On county scale, of 43 jurisdictional districts and counties in Guanzhong region, most of which are water resource overloading area, and in 1997, there are 40 districts and counties being overloading area, 1 human being - water balance area and 2 being water resource abundance area. In 2001, there are 37 districts and counties being overloading area, 3 being human being - water balance area and 3 being water resource abundance area. In 2006, there are 35 districts and counties being overloading area, 5 being human being - water balance area and 3 being water resource abundance area.The progress and innovation points of this paper are as follows:First, based on the water resource load index, the utilization and development potentiality of water resource in Guanzhong region are evaluated systematically, and the balance relation of population-economy development and water resource in this study area is revealed quantitatively on the scale of district, city region and county region.Second, on the scale of district, city region and county region, based on the water resource carrying capacity according to the national unified standards, the changes of population scale in time and space which could be supported continuously by the water resource of the study area are analyzed systematically, difference analysis of the population which could be supported and the actual population is conducted, and the quantity and scale of overloading or surplus population is determined in time and space.Third, based on the water resource carrying index and the balance relation of human and water, the study area is divided to water resource overloading district, human beings -water balance district and water resource volume abundance district on the scale of district, city region and county region.Forth, based on the water resource carrying status of the study area, several constructive suggestions are proposed.