摘要
【目的】研究退耕还林前后近30年陕西省安塞县的降雨量、蒸发量、径流量和含沙量等水文因子的变化特征,并揭示其变化趋势,为退耕还林(草)工程生态效益的客观评价提供参考。【方法】根据安塞站近30年(1980-2008年)的水文实测数据,统计分析了降雨量、蒸发量、径流量、径流模数、径流深度和含沙量等水文要素年内和年际变化;比较分析了退耕还林前后水文要素的变化特征和变化趋势。【结果】安塞县降雨量、蒸发量和含沙量年内分配不均,主要呈现季节性特征。降雨量、径流量和含沙量的年际变化大,而蒸发量的年际变化较小。退耕还林前,降雨量呈下降趋势,蒸发量、干旱指数、径流量和含沙量均呈增加趋势;退耕还林后,降雨量和蒸发量均有不同程度的增加,而且随着退耕还林年限的增加,降雨量呈现出增加趋势,蒸发量、干旱指数却呈现出下降趋势,径流量和含沙量均大幅下降并呈现减少趋势;各水文因子之间存在极显著性差异,降雨量与蒸发量呈极显著负相关,径流量与含沙量呈极显著正相关。【结论】退耕还林(草)工程实施后,安塞县各水文因子发生了较大变化,呈现出整体持续向好的趋势,生态环境也有了明显改善,可见退耕还林(草)工程的生态效益是显著的。
【Objective】 Hydrological factor is an important indicator of quality change about regional ecological environment.The research was to study the variation of hydrological factors for evaluating ecological benefit of the grain-for-grass project objectively.【Method】 According to measured hydrological data in Ansai County Hydrological Station,hydrological factors’ characteristics and trend of Ansai County in the past 30 years were analyzed.【Result】 Rainfall,evaporation and sediment concentration were uneven within a year.Annual changes of rainfall,runoff and sediment were large,while the annual changes of evaporation were small.Before the grain-for-grass projects：Rainfall showed adecreasing trend,evaporation,runoff and sediment concentration showed an increasing trend.After the project：Rainfall and evaporation has increased in varying degrees,but rainfall shows an increasing trend,while evaporation an decreasing trend,runoff and sediment concentration were significantly decreased and showed a decreasing trend.【Conclusion】 After the adoption of the grain-for-green project,hydrological factors showed great changes and robust growing trend in Ansai County.The ecological environment has also been significantly improved.The ecological efficiency of the project is significant.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2011年第8期178-184,189,共8页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金项目"人工植被对土壤和气候的微生态效益研究"(30971695)
关键词
安塞县
水文要素
变化特征
Ansai County
hydrological factor
variation characteristics
