干旱区人工绿洲水土资源承载状态演变分析

Analysis on evolution of carrying state of water and soil resources in artificial oases in arid areas

为明晰干旱区人工绿洲水土资源承载状态在时间序列上的演变过程,以甘肃省景电灌区为例,引入多级模糊分级理论建立水土资源承载状态综合评价指标体系.基于熵权法和物元分析理论构建物元分析模型,同时集成黄金分割率、组合赋权法及云理论构建综合评价云模型,对灌区1994,2002,2010及2018年的水土资源承载力状态进行综合评估.结果表明:水土协调度和地下水矿化度是灌区水土资源承载力发生变迁的主导因素;研究区各时期水土资源承载状态均处于“轻微承载-承载良好”,整体上呈良性演变趋势;水土资源承载力综合评价云的熵值(En)及超熵值(He)分别为0.0271,0.0263,0.0244,0.0267和0.0067,0.0078,0.0065,0.0057,数值较小,且He/En小于1/3,表明评估结果与实际水土资源承载状态呈现一致性.

In order to clarify the evolution process of the water and soil resources bearing status of the artificial oasis in arid area in time series,taking Jingdian Irrigation Area in Gansu Province as an example,the multi-level fuzzy classification theory was introduced to establish a comprehensive evaluation index system of the water and soil resources bearing status.Based on entropy weight method and matter element analysis theory,a matter element analysis model was built,and a comprehensive evaluation cloud model was built by integrating the golden ratio method,combination weighting method and cloud theory to comprehensive evaluation of water and soil resources bearing capacity of the irrigation area in 1994,2002,2010 and 2018.The results show that the water and soil coordination degree and groundwater mineralization degree are the dominant factors for the change of water and soil resources bearing capacity in the irrigation area.The bearing capacity of water and soil resources in the study area is between″slight bearing and good bearing″state in all periods,showing a benign evolution trend as a whole.The entropy(En)and super entropy(He)values of the comprehensive evaluation cloud of water and soil resources carrying capacity are 0.0271,0.0263,0.0244,0.0267 and 0.0067,0.0078,0.0065,0.0057,respectively,which are small values and He/En is less than 1/3,indicating that the assessment results are consistent with the actual water and soil resources carrying state.