The Evaluation Of Groundwater' Carrying Capacity In Pengshan District Of Meishan City

Groundwater is an invaluable resource for Pengshan district in Meishan City, it's rather a daunting task for us to make the sustainable utilization of the groundwater.With the rapidly growing economy and a rising number of urban population in recent years, some environmental and resource issues began to appear. Among them, the shortage of groundwater is the especially influential one, and cause a noticeable setback both for people's daily life and the city's development.This paper took the evaluation of groundwater's carrying capacity in Pengshan district as a main research content. We started the research with identifying the current groundwater situation, then combined society economy, environment and geological background into consideration to calculate the potential available groundwater resources.We set up an evaluation index system of groundwater's carrying capacity to determine the weight of each index by data processing and theoretical studying as well as by using Delphi method and Entropy method. To improve the accuracy, we took the weighted average results between the two methods for individual evaluation of each indicator and the comprehensive analysis of all the indicators.The main results are as follows:(1) This paper elucidates geological environments, hydrogeological conditions, groundwater storage modes, hydrological properties and hydraulic characteristics in Pengshan district and then divides the groundwater into two types: the loose rock pore water and the bedrock fissure water. Then we determine hydrogeological parameters needed for this evaluation.(2) Base on all the information mentioned above, we choose 11 different indicators appropriate to Pengshan district to form the evaluation system of groundwater's carrying capacity. The 11 indicators are: groundwater recharge resources(C1), available groundwater resources(C2), water environmental capacity(C3), domestic water consumption(C4), industrial water consumption(C5), irrigating water(C6), ecological environment of water(C7), wastewater emissions per 10,000 yuan of GDP(C8), industrial wastewater discharge compliance rate(C9), groundwater resources exploitation capacity(C10), groundwater resources capacity(C11).(3)The evaluation results show that the status of groundwater's carrying capacity are different among the evaluation units significantly. Groundwater resource is a major problem in low mountain areas, where its groundwater's carrying capacity is overloaded in towns such as Yihe, Xie, Gongyi, Muma, Jinjiang, Jiangkou, Huangfeng and Baosheng. In the plain areas, take the social economic development and utilization of water into account, the groundwater's carrying capacity is in balanced or surplus condition in towns like Pengxi, Fengming, Wuyang, Guanyin and Qinglong.(4)The main present problems of groundwater's carrying capacity in Pengshan strict are as follows: low utilization level of water resource, increasingly poor water environment, serious water pollution, irrational exploitation of groundwater and unsound management. All the problems are more prominent in low mountain areas and that requires timely attention and improvement.