摘要
采用Thornthwaite湿润指数对松嫩平原进行气候分区,并利用2000-2009年SPOT/VGT逐旬最大合成值NDVI数据和研究区内17个气象站点数据,分析研究区不同气候区植被NDVI与气象因子的相关关系,以探讨NDVI对气候变化响应滞后性的时空特征。结果表明,(1)NDVI与同期旬平均气温、旬平均最高气温、旬平均最低气温呈极显著正相关(P<0.01),相关系数大小依次为湿润区>半湿润区>半干旱区;NDVI与同期旬降水量、旬平均相对湿度呈显著正相关(P<0.05),相关系数依次为半干旱区>半湿润区>湿润区。(2)NDVI与各气象因子逐步回归结果表明,最低气温是NDVI变化的限制性因子,且在3个气候区中,最低气温对NDVI的贡献最大;降水是湿润区和半湿润区影响植被生长的最重要因素,而在半干旱区,相对湿度对NDVI的贡献大于降水。(3)NDVI对温度响应的滞后期在湿润区为20d,半湿润区为20～30d,半干旱区为30d;对降水响应的滞后期在湿润区为30d,半湿润区为20d,半干旱区为10d,且NDVI对相对湿度响应的滞后期比降水短;空间上NDVI对温度响应的滞后期从东到西逐渐变长,而降水则相反。
Songnen plain was divided into climatic zones with thornthwaite humid index. The time lag character of the NDVI to climate change was discussed by using correlation between the SPOT/VGT NDVI and meteorological data. The results showed that there were significant positive correlation between NDVI and mean temperature, mean mini- mum temperature, mean maximum temperature 10-day （P 〈0. 01 ）, between NDVI and precipitation, relative humidi- ty 10-day （P 〈 0. 05）. The minimum temperature 10-day was restrictive factor to NDVI. Precipitation was the most important contributor to NDVI in humid and semi-humid area, but the relative humidity was more important to NDVI than precipitation in semi-arid area. Time lag of NDVI to temperature was 20 days in humid region, 20 - 30 days in semi-humid region and 30 days in semi-arid days, and which to precipitation was 30 days in humid region, 20 days in semi-humid region and 10 days in semi-arid days. Time lag of NDVI to humidity was shorter than that to precipitation.
出处
《中国农业气象》
CSCD
北大核心
2012年第2期271-277,共7页
Chinese Journal of Agrometeorology
基金
东北师范大学“十一五”科技创新平台(106111065202)
国家重点基础研究发展规划(973)项目(2009CB426305)
关键词
松嫩平原
NDVI
气象因子
气候区
滞后性
Songnen plain
NDVI
Meteorological factors
Climatic zones
Time lag
