摘要
研究洱海近岸菜地浅层地下水埋深是合理调控浅层地下水位和防止土壤氮磷随浅层地下水流失的基础。通过对洱海近岸菜地2 a(2014年6月—2016年5月)浅层地下水埋深进行监测,分析了浅层地下水埋深的时空变化特征和影响因素。结果表明,洱海近岸菜地5个高程浅层地下水埋深均服从正态分布,其平均值为25.21~45.07cm,变异系数在0.26~0.43之间。浅层地下水埋深旱季深、雨季浅,其月变化和雨、旱季不同期,存在滞后现象,雨季浅层地下水埋深变异系数大于旱季。旱季和雨季浅层地下水埋深空间变化随等高线均呈不规则带状分布。洱海水位、降雨、灌溉、潜水蒸发和土壤物理特性的空间变异均是影响洱海近岸菜地浅层地下水埋深变化的主要因素。其中,1 966 m高程浅层地下水埋深与洱海水位极显著线性相关(p<0.01),二者互为连通,相互补给;其他高程浅层地下水埋深与降雨量和灌溉量显著线性相关(p<0.05),随降雨量增加,浅层地下水埋深逐渐变浅,随潜水蒸发量和灌溉量增加,浅层地下水埋深逐渐变深。距洱海由近及远土壤母质为河湖相沉积物到第四纪红黏土,使得不同发生层土壤渗水性由强变弱,造成离洱海越远,海拔越高,浅层地下水埋深越浅,变幅越小。
Understanding the dynamics of shallow groundwater table in the nearshore vegetable field of the Erhai Lake was essential for regulating groundwater resources and preventing nitrogen and phosphorus leaching. Based on groundwater data measured from June 2014 to May 2016 in the nearshore vegetable field, we analyzed the dynamics of the groundwater depth and the factors affecting it. The results showed that the shallow groundwater depth at different elevations showed a normal distribution and the average depth of shallow groundwater table was from 25.21 cm to 45.07 cm with variation coefficient of 0.26 to 0.43. The shallow groundwater depth was deeper in the dry season than in the rainy season, and its monthly variation in the rainy reasons differs from that in dry reasons, characterized by a hysteresis. The variation coefficient of the shallow groundwater depth in the rainy season was greater than that in the dry season. The spatial variation of the shallow groundwater depth showed irregular distribution. The water level of the Erhai Lake, rainfall, irrigation, phreatic evaporation and spatial variability of soil physical properties were the main factors that affect the shallow groundwater depth in the nearshore vegetable field. There was a good linear correlation between the shallow groundwater water depth at el- evation of 1966 m and the water level of the Erhai Lake （p〈0.01）. There were also good linear correlations be- tween the shallow groundwater depths in other areas and the rainfall, irrigation （p〈0.05）. The soil parental material was from fiver-lacustrine facies deposits into Quaternary red clay away from the Erhai Lake, and the permeahility of different soil genesis were from stronger to weaker. These factors caused shallow groundwater depth was shallower and the smaller change range of water level with the farther away from the Erhai Lake and the higher the altitude.
出处
《灌溉排水学报》
CSCD
北大核心
2017年第12期101-109,共9页
Journal of Irrigation and Drainage
基金
国家自然科学基金项目(41401248,41661048)
云南省农科院环资所所长基金项目(hz2013001)
国家水体污染控制与治理科技重大专项(2014ZX07105-001)
关键词
菜地
洱海
浅层地下水埋深
时空变化
影响因素
vegetable field
Erhai Lake
shallow groundwater depth
spatial and temporal variation
influencingfactors
