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一引言地下水动态问题实质上是地下水补排平衡问题。即当补给量大于排泄量时,地下水位上升,反之则下降。据多年地下水观测资料分析,宁夏银北灌区地下水位的年、季变化特点是,灌水期为灌溉——蒸发型;土壤冻融期为冻结吸水和融冻释水型。灌区地下水垂直运动强烈,水平运动微弱;地下水补排关系在自然因素和灌溉控制下达到近乎平衡状态。年际变化具有潜在的周期性;年内变化灌溉起主导作用,非灌期蒸发等自然因素起主要作用。为实现对灌区地下水位可观可控之要求,并为灌区的科研与科学管理提供依据,本文对
I. INTRODUCTION The issue of groundwater dynamics is essentially the issue of groundwater recharge and balance. That is when the recharge is greater than the amount of discharge, the groundwater level rises, otherwise decreases. According to the analysis of groundwater observation data for many years, the annual and seasonal variation of groundwater level in Yinbei Irrigation District in Ningxia is characterized by irrigation-evapotranspiration during freezing period and frozen-water absorption and freeze-thaw-releasing water release during soil freezing and thawing periods. The vertical movement of groundwater in irrigated area is strong, and the horizontal movement is weak. The relation between groundwater recharge and discharge reaches an almost equilibrium state under the control of natural factors and irrigation. The interannual variation has the potential of periodicity. During the year, the dominant irrigation played a dominant role, and irrigation and other natural factors played a major role. In order to realize the requirement of considerable and controllable groundwater table in irrigation district and provide the basis for scientific research and scientific management in irrigation district,