摘要
近46年来石羊河流域的气温呈持续升高趋势,1994年显著变暖。与变暖前相比,年平均气温偏高1.0℃,线性增温速率快7倍。显著变暖后,流域年降水增加了15%(约15.8mm),出山口径流却呈略减少趋势(约2.2亿m3),地下水位也在快速降低。出山口径流的略减少发生在上游山区年降水量减少的大背景下,人类活动是影响流域中游地表径流利用量和下游可利用量变化的主要原因。对植被的监测表明,以荒漠草甸和沙生植被为主的稀疏植被面积在快速减少,同时还存在植被类型的退化现象,植被覆盖面积和地下水位埋深两者呈显著负相关。受气候变化和人类活动的共同影响,石羊河流域的生态环境正在趋于恶化。近46年来石羊河流域的气温呈持续升高趋势,1994年显著变暖。与变暖前相比,年平均气温偏高1.0℃,线性增温速率快7倍。显著变暖后,流域年降水增加了15%(约15.8mm),出山口径流却呈略减少趋势(约2.2亿m3),地下水位也在快速降低。出山口径流的略减少发生在上游山区年降水量减少的大背景下,人类活动是影响流域中游地表径流利用量和下游可利用量变化的主要原因。对植被的监测表明,以荒漠草甸和沙生植被为主的稀疏植被面积在快速减少,同时还存在植被类型的退化现象,植被覆盖面积和地下水位埋深两者呈显著负相关。受气候变化和人类活动的共同影响,石羊河流域的生态环境正在趋于恶化。
The annual average temperature of the overall Shiyang river basin has a continuous warming trend for the recent 46 years, with 1994 being significantly warm. Compared with the previous warming, the average temperature increased by 1.0℃ , and linear warming rate was 7 times faster. After the warming, annual rainfall was increased by 6.5% （about 16. lmm）, runoff from mountain pass was slightly decreased （about 220 million m^3）, and the water table rapidly lowered. The runoff from mountains pass dropping slightly occurred in the context of decreasing mountain precipitation. Human activities were the main reasons which caused the changing of midstream and downstream utilization volume in the Shiyang river basin. Vegetation monitoring indicates that the area of sand meadow vegetation mainly of sparse vegetation is reducing rapidly and vegetation type is degenerating in the Shiyang River basin, vegetation coverage area and the basin water level were negatively correlated. Based on the climate change and human activities, the ecological environment is worsening in Shiyang river Basin.
出处
《地球科学进展》
CAS
CSCD
北大核心
2007年第7期730-737,共8页
Advances in Earth Science
基金
国家自然科学基金项目"典型内陆河区域河西走廊地区降水规律的研究"(编号:40435016)
"西部开发科技行动"重大项目"祁连山空中云水资源开发利用研究"(编号:2004BA901A16)资助.
关键词
石羊河流域
气候变化
水资源NDVI
生态环境
Shiyang river basin
Climate change
Water resource
NDVI
Ecological environment.
