华北平原植被动态对气象干旱的响应特征

基于中国华北平原1982—2012年NDVI和不同时间尺度SPI/SPEI数据,分析了植被绿度年际波动对气象干旱时间尺度的响应特征。结果表明:华北平原干旱对春季植被绿度的影响强于夏季,对北部的影响强于南部;植被绿度对长期干旱的响应更明显,但局部和季节差异非常明显,北部植被响应干旱的时间尺度较南部短;生长季水分亏缺是其植被干旱脆弱性的主导因素。

Response Characteristics of Vegetation Greenness to Different Time-scale Meteorological Droughts in Northern China Plain

We evaluated the response of different land biomes to drought by correlating the various timescale SPEI/SPI with a widely used indicator of vegetation activity,like the Normalized Difference Vegetation Index (NDVI) in Northern China Plain (NCP) during 1982-2012.The results showed that the NDVI of spring cultivated vegetation were more sensitive to drought than that of summer vegetation , and the impact of drought on vegetation greenness in northern was more significant than that in southern .The response of vegetation to drought was usually more obvious at a long scale,but the strongest response timescale in northern was shorter than southern .In a word,water deficit during the growing season was the main driver of vegetation vulnerability to drought .