灌溉对大同盆地高砷地下水的影响

Effect of Irrigation on High Arsenic Groundwater in Datong Basin

本次试验的主要目的是研究采取深层地下水灌溉对浅层地下水造成的影响。经过现场值以及后期带回测定的样品的处理和分析,笔者发现地下水中电导率、溶解氧、砷含量、氢氧同位素指标在灌溉水入渗、氧化还原、蒸发等多种作用混合的情况下发生明显变化。尤其在2.0 m的潜水面处多次出现峰值,并且随着灌溉的进行出现相应的滞后现象,很多明显的变化在灌溉停止后才逐渐显现。由此可见,灌溉对研究区域地下水水化学场造成了显著的影响,其具体表现为潜水面的升降及地下氧化还原条件的变化。

The main purpose of this experiment is to study the influence of deep groundwater irrigation on shallow groundwater. Through the analysis of the scene and later back to the value of the sample was measured, the author found that the underground water conductivity, dissolved oxygen, arsenic content and isotopic indicators changed significantly in irrigation water infiltration, evaporation, oxidation and reduction of various functions such as mixed case. Especially in the phreatic surface of 2 m, many peaks occurred, and the corresponding hysteresis appeared with the irrigation. Many obvious changes appeared gradually after the irrigation stopped. This shows that irrigation has a significant influence on the hydrochemical field of groundwater in the study area, which is manifested as the rise and fall of phreatic water and the change of underground redox conditions.