50a来宁夏可利用降水的时空变化及其对生态环境的影响  

Spatial-temporal Changes of Available Precipitation for 50 Years in Ningxia and Its Effect on Environment

作　　者：陈豫英[1] 陈楠[1] 王式功[2] 陈晓光[1] 穆建华[1] 

机构地区：[1]宁夏气象防灾减灾重点实验室,宁夏银川750002 [2]兰州大学大气科学学院,甘肃兰州730000

出　　处：《中国沙漠》2008年第4期748-754,共7页Journal of Desert Research

基　　金：国家科技部社会公益研究专项项目(2004DIB3J121);中英气候变化双边合作研究项目(2001-BA611B-04-06-01);中国气象局气候变化专项项目(CCSF2006-16,CCSF2007-27);宁夏自然科学基金(NZ0648)共同资助

摘　　要：利用1955—2006年宁夏气温、降水资料,计算了水分资源各分量,并结合1982—2003年植被指数(NDVI)值,分析宁夏水分资源各分量的变化及其对生态环境的影响。结果表明:宁夏水分资源各分量时空分布极不均匀,夏季最大,冬季最小,南部较北部水分资源相对丰富;50 a来降水和可利用降水呈下降趋势,蒸发呈上升趋势,各分量大体经历了4个变化阶段;四季中秋季可利用降水的突变特征最明显,突变年在1978年,突变后各地区可利用降水明显减少,中部干旱区最明显;水分资源各分量有明显的16 a、8 a和4 a左右的周期变化。近20 a宁夏植被覆盖率整体得到提高,进一步分析表明,宁夏大部NDVI值的变化与自然环境和水分资源密切相关。Each variable component of water resources in Ningxia was calculated based on the precipitation and temperature data from 1955 to 2006, which combined with the NDVI data from 1982 to 2002 the effect of water resources variation on eco-environment was analyzed. The spatial-temporal distribution of each variable component of water resources in Ningxia was much asymmetric; it was the largest in summer and the smallest in winter, and the more abundant in south than that in north. In recent 52 years, precipitation and available precipitation in Ningxia showed a downtrend, and the evaporation showed an uptrend; each variable component experienced four variational stages on the whole. The saltation characteristic of available precipitation was most remarkable in autumn and the saltation year is in 1978, after the saltation the available precipitation reduced evidently especially in the middle arid area. Each variable component has remarkable changing periods of 16a, 8a and 4a. In recent 20 years, the vegetation coverage rate was improved, and more analysis showed that the variation of NDVI value in Ningxia closely related with natural environment and water resources.

关 键 词：宁夏 可利用降水 NDVI变化 生态环境 

分 类 号：P339[天文地球—水文科学]