植被状态指数监测西北干旱的适用性分析  

Applicability Analysis of VCI to Monitoring Northwest China Drought

作　　者：管晓丹[1,2] 郭铌[2] 黄建平[1] 葛觐铭[1] 郑志海[1] 

机构地区：[1]兰州大学大气科学学院,甘肃省干旱气候变化与减灾重点实验室,甘肃兰州730000 [2]中国气象局兰州干旱气象研究所,甘肃兰州730020

出　　处：《高原气象》2008年第5期1046-1053,共8页Plateau Meteorology

基　　金：科技部公益研究项目“中国干旱气象灾害监测预警方法研究”(2004DIB5J192);国家自然科学基金项目(40375011)共同资助

摘　　要：利用1982—2003年22年逐月GIMMS 8 km分辨率的NDVI数据和西北地区138个气象台站同期月降水数据,分析了植被状态指数(VCI)对西北地区历史干旱的监测能力。根据西北气候和植被类型的特点,选取雨养农业区、灌溉农业区和青藏高原高寒草原区为典型研究区域,研究了VCI对不同地区气象干旱的监测能力,并对VCI监测干旱的适应性进行分析。结果表明:VCI可以较好地反映西北大部分历史干旱的空间分布及其演变特征。对于不同的气候区域,VCI监测干旱的效果存在一定的差别。对于西北东部的雨养农业区,VCI能够较好地反映降水的盈亏对植被影响,是监测这一地区干旱的有效指标;在西北区西部的灌溉农业区,VCI基本不能反映这一地区降水的多寡,不能作为这些地区气象干旱监测的指标;VCI也不能反映青藏高原高寒草原区降水的亏缺,不能作为监测这些地区气象干旱的指标;在极涡干旱的戈壁、沙漠地区VCI会出现虚假的高值。The capability of Vegetation Condition Index （VCI） monitoring drought in northwest China was analyzed using GIMMS NDVI data set from January 1982 to December 2003 and the monthly precipitation data at 138 meteorological stations during the same period. The NDVI data set was collected at spatial resolution of 8× 8 km^2 and one month interval. According to the characteristic of climate type and vegetation planting in the northwest region, several typical research regions including rain-fed areas, irrigated areas and the grassland at the Qinghai-Tibet Plateau were chose . The applicability of VCI monitoring drought in different areas was studied in northwest China. The results show that VCI can reflect the drought spatial distribution and the development commendably in most of the areas in northwest China. The effect in VCI monitoring drought were different in these research regions. The VCI could preferable monitor the drought in rain-fed areas, it is an effective index in monitoring meteorological drought. The VCI were not useful in monitoring the drought happened in irrigated districts and in the grassland in Qinghai-Xizang Plateau. The VCI appears abnormal high value in the desert regions.

关 键 词：西北地区 VCI 降水距平百分率 雨养农业区 灌溉农业区 

分 类 号：P463.22[天文地球—大气科学及气象学]