论文部分内容阅读
对地下水动态的研究是地下水资源评价和合理开发利用的基础。本文通过在黄河三角洲代表性区域黄河农场地区的典型地貌单元上安装的自计水位计,获得自2004年5月到2005年5月30分钟一次的浅层地下水水位和水温动态资料,和其中一个观测孔地下水电导率动态。结合同时期日降水量资料,阐明一个完整水文年内浅层地下水对降水入渗补给的响应过程和特点,讨论了浅层地下水动态形成的机理。主要结论有:①沉积物之间岩性的差别导致浅层地下水动态类型的差别。泛滥平原相沉积物中地下水的动态类型为渗入-蒸发型,而河流相沉积物中地下水的动态类型为渗入-径流-蒸发型。降水是引起浅层地下水水位上升的主要因素;②浅层地下水温度变化主要受大气温度年内周期变化的驱动,然而雨季日降水量大于10mm时地下水温度平均升高约0.3℃;③进入雨季后累积降水量超过300mm是地下水EC值对降水响应的阈值,雨季降水对浅层地下水有暂时的淡化作用。
The study of groundwater dynamics is the basis of groundwater resources assessment and rational development and utilization. In this paper, the dynamic data of groundwater level and water temperature of shallow groundwater from May 2004 to May 2005 was obtained through the self-designed water level meter installed on the typical landform unit of the Yellow River farm in the representative region of the Yellow River Delta, and one of them Observation hole groundwater conductivity dynamic. Based on the daily precipitation data of the same period, the response process and characteristics of shallow groundwater to rainfall infiltration recharge in a complete hydrology year are elucidated. The mechanism of dynamic formation of shallow groundwater is discussed. The main conclusions are as follows: (1) The difference of lithology between sediments leads to the difference of the dynamic types of shallow groundwater. The dynamic type of groundwater in flood plain sediments is infiltration-evaporization type, and the dynamic type of groundwater in river sediment is infiltration-runoff-evaporation type. Precipitation is the main factor that causes shallow groundwater level rise. (2) The change of shallow groundwater temperature is mainly driven by the annual cycle change of atmospheric temperature. However, when the daily precipitation is more than 10mm, the groundwater temperature increases about 0.3 ℃ on average; Precipitation greater than 300mm is the threshold for the response of groundwater EC to precipitation. Precipitation in rainy season temporarily desalinates shallow groundwater.