摘要
克拉玛依农业开发区位于温带荒漠气候区,开发建设10余年来地下水位发生了明显抬升,土壤盐渍化威胁变得十分严重。本文利用地下水水位重复观测、地形测量、气象与径流监测数据分析了开发区的地下水位变化过程,并探讨了地下水位变化与气候、地貌、土壤、周围径流补给以及灌溉的关系。发现开发区的地下水位10年间基本呈现持续上升的过程,自1999年建设以后开发区地下水位发生了普遍抬升,整个开发区地下水位平均上升了7.30m,年平均0.73m/a,但存在明显的空间差异。分析认为灌溉是开发区地下水位上升的主要原因,但南部玛纳斯河下泄径流和北侧山麓洪积扇地下水的补给也起到一定的作用,气候变化影响不大。区内地下水位上升的空间差异主要与地貌及土壤组成条件关系密切。
The Karamay agricultural development region is located on the lacustrine plain of the ancient Manas Lake to the south of Karamay City, Xingjiang Uygur Autonomous Region. After about ten years of land reclamation, the groundwater level under the region has been uplifted significantly and agricultural production is threatened by serious soil salinization. Based on measurements of groundwater level, terrain, rainfall, temperature and hydrological data, the authors investigated the processes and the main causes of changes in groundwater level under the agricultural development region. It was found that before the land reclamation the groundwater level was higher in the northern and southern wings of the region than was in its middle part. It was also higher at the west end than at the east end. This led to the formation of a channel of groundwater level which orients the groundwater flowing from the southwest to the northeast. Since agricultural production began after 1999, a widespread rising of groundwater level has taken place in the region, with an average total of 7.3 m according to the data gauged in 1997 and 2009, and an annual mean of 0.73 m/a. The elevation of groundwater level was much eye-catching on the eastern side of the highway across the region from the north to the south. The groundwater level there was uplifted from the bottom of groundwater level channel to a hillock and then to a high ridge of groundwater level extending from the south to the north. Contrasting to the high ridge, a depression of groundwater level was observed on the western side of the highway. The study shows that the rising of groundwater level can be attributed mainly to the high irrigation mode and partly to the replenishment of groundwater coming from the intermittent water flow in the Manas River to the south, and from small seasonal creeks flowing down the Genghis Khan Mt. to the north. The low-lying and gentle terrain and clayey soil are considered the favorable geologic and geomorphic conditions for groundwater level rising of the region. Moreover, the spatial variations in groundwater level rising are probably associated with spatial heterogeneity in terrain and soil grainsize composition. The groundwater level is generally high at places with a high ground surface, and vice versa. However, the uplifted height of groundwater level is negatively correlated with the elevation of the ground surface. The groundwater level was uplifted much higher in soils with higher silt and sand content than was in soils with higher clay content. Although precipitation increased in the recent ten years in Karamay, its increment may not be able to balance the elevated evaporation due to climate warming. Therefore, the changes in climate in recent years did not make a noticeable contribution to the groundwater level rising over the region.
出处
《资源科学》
CSSCI
CSCD
北大核心
2010年第10期1883-1889,共7页
Resources Science
基金
中国科学院西部行动计划项目(编号:KZCX2-XB2-13)
关键词
干旱区农业
地下水
灌溉
土壤盐渍化
Arid-zone agriculture
Groundwater
Irrigation
Soil salinization