乌兰布和沙漠东北边缘人工绿洲地下水动态研究

STUDIES ON GROUNDWATER DYNAMICS OF THE ARTIFICIAL OASES IN THE NORTHEASTERN ULAN BUH DESERT

通过对人工绿洲内及荒漠对照区不同时期地下水位、水质的监测分析，结果表明，绿洲因受灌溉水下渗的影响，与荒漠区相比，地下水位有较大的升高，１５年间地下水位上升了２．４ｍ，年平均升高１６ｃｍ；绿洲地下水位的升高在绿洲开发初期与后期变化较大，前期上升幅度较大（年升高２５ｃｍ），后期上升幅度较小（年升高１０ｃｍ）；因受灌溉季节的影响，地下水埋深在一年中变化较大，丰水季与枯水季水位相差２ｍ左右，且某些地段超过潜水蒸发临界埋深；随绿洲开发年限的增加，绿洲内地下水质趋于变差，特别是在地势较低地域及灌渠两侧，地下水矿化度较高，某些地段出现卤水（矿化度高达９．２９ｇ／ｌ）；地下水水质变差及埋深变浅，均可引起土地次生盐渍化。

Through the monitoring of the groundwater level and the analysis of its quality in the artificial oasis and the desert area for 15 years,the results show:1.The groundwater level has a significant rise in the oasis by contrast with desert area because of the infiltration of irrigation water.It has rose 2.4m in 15 years and the average annual rise is 16cm;2.The groundwater quality in the oasis is getting worse with the increase of the oasis development year,especially in the low lands and the bilateral irrigation canals,in which some groundwater has become bittern water(minerality is 9.29g/l); 3.Both high groundwater level and bad quality have caused the soil salinization.