地下水遥感模糊评估指数的构建与研究

为提高地下水定量遥感的评估精度,完善评估内容,扩大评估模型的适用范围,本文从水文地质的角度出发对地下水赋存空间、补给条件和地表指示进行研究,确定以地层岩性、断裂密度、地形坡度、地貌类型、汇流累积量、地表温度、土壤湿度作为地下水富集性评估的7个指标.选择具有代表性和典型性的丹东为研究区,利用ALOS、SPOT、TM和DEM数据对7个指标进行提取和解译,通过分析各指标对地下水富集性的影响特性,首次建立模糊隶属度函数对各指标进行模糊评判.利用层次分析法分别计算孔隙型地下水和裂隙型地下水各指标的权重,采用加权合成算法首次建立了地下水遥感模糊评估指数GRSFAI.研究区实地调查的钻井和泉眼数据表明:GRSFAI与孔隙水出水量的决定系数为0.82,与裂隙水出水量的决定系数为0.57.依据研究区GRSFAI的分布特点对地下水富集性进行评估分级,分级结果与实际情况一致,与地下水分布规律相符.分析认为:GRSFAI能准确反映地下水富集程度,评估结果可靠,具有良好的适用性和推广应用能力.

Construction and investigation of groundwater remote sensing fuzzy assessment index

In order to improve the precision of assessment in groundwater quantitative remote sensing, perfect the evaluation content and expand the application scope, this paper studied the storage space, supply condition and surface indication of groundwater through hydrogeology analysis, and selected lithology, fault density, slope, relief, flow accumulation, land temperature, and soil humility as 7 factors to evaluate groundwater potential. Took Dandong as representative and typical research area, the 7 factors were extracted and interpreted from ALOS, SPOT, TM and DEM data. Fuzzy membership functions were established for the first time through analyzing each factor's impact on groundwater enrichment, and factor weights were calculated by analytic hierarchy process (AHP) for pore water and fissure water respectively. The groundwater remote sensing fuzzy assessment index (GRSFAI) was constructed using weighted synthesis algorithm and tested by field investigation data of drilling and spring. The results showed that the R² between GRSFAI and well/fountain quantity is 0.82/0.57. According to distribution characteristic of GRSFAI, the groundwater potential of study area was graded. It came out to be well consistent with field validation and the law of groundwater distribution. In a word, GRSFAI can well reflect groundwater enrichment, its evaluation is accurate and reliable, and has good applicability.