Study On Vulnerability Of Water Resources In Handan

The total amount of water resources in Handan is about 1.67×10~9m~3,and the per capita water resource is 191m~3,accounting for only 9%of the country's total per capita water resources.In recent years,the actual utilization of water resources in Handan has reached 1.90×10~9m~3,of which surface water is 0.50×10~9m~3,accounting for only 1/4 of the total water consumption.Due to the shortage of surface water,the local groundwater is overexploited for a long time,and the groundwater level is falling.This leads to the change of dynamic conditions,the environmental damage of aquifer and the pollution of groundwater quality,forming a vicious circle.With the rapid development of economy and the continuous growth of population,the water consumption of production and life increases,and the discharge of waste water increases year by year.Finally,the shortage of water resources becomes more and more serious.All of these have become the key factors affecting the social and economic health and sustainable development of Handan.The water resources system in Handan has been gradually destroyed,and its fragility also has been gradually highlighted.Therefore,how to determine the vulnerability of water resources,in order to analyze its restriction to the social,economic and ecological environment of this city,has become an urgent problem to be solved for the sustainable utilization of water resources.But up to now,few studies focused on the asseement of water resources system vulnerabilityin Handan.In order to reasonably evaluate the vulnerability of water resources system in Handan,this paper presents a Modified Ordered Weighted Averaging(MOWA)model based on Extended Ordered Weighted Averaging(EOWA)and Principal Component Analysis(PCA).The advantages of this model are as follows:(1)Several uncertainties in the evaluation system are quantificationally represented based on EOWA operator;(2)Because the using of cumulative contribution rate,it can not only avoids overlapping and crossing of indexes,but also retains the authenticity of the original index,thus avoiding the subjective randomness.(3)It can effectively reflect the importance of different decision-making levels in the evaluation system through using order weight and reduce the extreme error.In this paper,MOWA model is used to objectively evaluate the vulnerability of water resources system in Handan from 2005 to 2015.The research contents include:(1)the interannual trend of vulnerability of water resources system in Handan in recent ten years;(2)continuous annual and spatial change trend;(3)the main influence factors of water resources system vulnerability in each area.The results show that the proposed MOWA in this paper can be used to evaluate water resources system vulnerability in Handan.The vulnerability of water resources system in Handan has obvious spatial distribution law,and the vulnerability is increasing gradually from south to north and from west to east.This is the same as the decreasing trend of the annual rainfall from south to north and from west to east.Among them,groundwater exploitation rate,population density and water resource utilization rate are the most important factors in vulnerability assessment.Therefore,the obtained results can provide scientific significance and good guidance for mentors,water managers and researchers in the management of water resources systems.