中文摘要：

以2002年、2007年Landsat5影像和2013年Landsat8影像为数据源,通过ENVI和Arc GIS对遥感影像进行校正和处理并提取采样点的土壤反射率盐分指数对12年来柳城子水库下游土壤盐渍化时空变化特征进行分析,结果表明：12002～2013年,土壤平均反射率盐分指数逐年升高2002年（0.164）〈2007年（0.183）〈2013年（0.206）;2在0～1200 m范围内土壤SI1（盐分指数）表现为2013〉2007〉2002年,但在1200～2400 m变幅较小,各年盐渍化趋于稳定;32002、2007、2013年SI1具有强烈空间相关性,空间自相关变化尺度逐年增加,表明区域因素（地下水）对土壤盐渍化空间变异性影响逐渐增长并向下游不断扩展;4在研究时段内,由于水库蓄水量的增加（2007年库容由2002年4×106m^3扩建为6×106m^3）,水库对下游土壤盐渍化的影响不断增强,导致其盐渍化程度逐渐加剧。2013年比2002年轻度、中度盐渍化土壤面积分别减少69.44%、37.57%,而重度盐渍化、盐土则从无到有分别增加了722589.71 m^2、1941395.51 m^2。不论是空间上,还是时间上,水库下游土壤盐渍化状况总体趋于更加恶化。

英文摘要：

Taken Landsat 5 images in 2002, 2007 and Landsat 8 images in 2013 as data sources, this paper calibrated and processed the remote sensing images by ENVI and Arc GIS and extracted the soil reflectance index of sampling points, analyzed the spatial-temporal variation characteristics of soil salinization for 12 years in Liuchengzi Reservoir downstream. Results showed that：（1） From 2002 to 2013, the average of reflectance index of soil salt（SI1） increased year by year： in 2002（0.164） 〈in 2007（0.183） 〈in 2013（0.206）;（2） At 0 ～ 1200 m distance, the SI1 value decreased following the order of： in 2013 in 2007 in 2002, but at 1200 ～ 2400 m distance its change was small with years and it tended to be stable;（3） In 2002, 2007, and 2013, SI1 had strong spatial correlation and the change scale increased year by year, which suggested that the impact of regional factors（groundwater） on the spatial variation of soil salinization gradually increased and expanded to downstream;（4） During the study period, the impact of reservoir on soil salinization in downstream was strengthened and further led to the aggravated salinization degree due to the increase in reservoirs pondage（capacity was expanded from 4 ×10^6m^3in 2002 to 6 ×10^6m～3in 2007）. The area of mild and moderate salinization was reduced by 69.44% and 37.57%, respectively, while that of severe salinization and saline soil was increased by 722589.71 m^2 and 1941395.51 m^2, respectively in 2013 when compared with in 2002.Overall, soil salinization condition in the reservoir downstream tended to be even worse in spatial and temporal scale.