煤矿排水影响下的水体水质特征及灌溉适宜性评价——以贵州织金县贯城河小流域为例

煤矿废水的直接排放影响下游农田灌溉的水体水质。以贵州省典型煤矿区织金县贯城河小流域为例,研究基于GIS的水质空间分布特征,并用EC、SAR、Na%和KI指数对地表水和地下水的农田灌溉适宜性进行评价。结果表明,受矿山开采的影响,地表水各物理化学参数变化范围较广,地下水中SO_4~(2-)含量范围变化较大;地表水和地下水中pH、EC、TDS、Ca~(2+)、Mg~(2+)、SO_4~(2-)和HCO_3~-具有较一致的空间分布特点;大部分地表水处于较适合灌溉水平,与矿山排水有水力联系的上游地表水体灌溉适宜性较差,而地下水均适合用于灌溉。

Water Quality Characteristics and Irrigation Suitability Evaluation Under the Influence of Coal Mine Drainage A Case Study of the River Watershed in Zhijin,Guizhou

The direct discharge of coal mine wastewater will affect the downstream water quality used for farmland irrigation .Based on the water quality spatial distribution characteristics of GIS ,this paper set the coal minding area in Guancheng River watershed of Zhijin county of Guizhou ,as a typical example and evaluated the applicability of surface water and groundwater for farmland irriga‐tion with the indexes of EC ,SAR ,Na% and KI .The results indicated that there existed significant differences among physical and chemical parameters in surface water affected by mining exploitation ;regarding the concentration ,the variation in groundwater was evident ;the pH ,EC ,TDS ,Ca2+ ,Mg2+ kept the comparatively consistent spatial distribution features in surface water as well as groundwater .Within the scope of the study ,most surface water was at a suitable level ,the applicability of upstream surface water having hydraulic contact with mine drainage was poor while all the groundwater was suitable for irrigation .