华北地区植被NDVI变化及与气候因子的关系

Research on the Variation of Vegetation NDVI and Its Relationship with Climatic Factors in Northern China

基于1982—2006年NOAA/AVHRR NDVI数据和华北地区56个气象站点温度和降水数据,从月、季节和生长季尺度上分析植被NDVI、温度和降水的年际变化及NDVI对温度和降水的响应。结果表明,从月尺度上来看,植被NDVI年变化以增加趋势为主,温度以增加为主,降水量以减少为主。从季节上讲,春季和秋季NDVI空间分布大体一致,与夏季呈相反趋势;春季和秋季时间序列NDVI呈上升趋势,夏季降低趋势较弱;春季升温最快,其次是夏季;夏季降水增加,春季和秋季降水减少。生长季NDVI呈增加趋势,温度每10 a增加0.48℃(P<0.01),降水变化趋势不明显。3,4,11月NDVI变化主要受温度限制,植被季节(春、夏、秋季)和生长季NDVI与温度的相关性均大于NDVI与降水的相关性,NDVI与温度的相关系数从大到小顺序是:生长季>春季>秋季>夏季,NDVI与降水的相关系数从大到小顺序是:春季>生长季>夏季>秋季。

Based on the remote sensing data, NOAA/AVHRR NDVI and meteorological data of 56 meteorological stations, temperature and precipitation, during 1982-2006 in the Northern China, the inter-annual variability of vegetation NDVI, temperature and precipitation and the response of NDVI to the temperature and precipitation were analyzed from monthly, seasonal and growing season time scales. From the monthly, the inter-annual change of vegetation NDVI and temperature were mainly increased, while the precipitation was mainly reduced. In view of the season, the spatial distribution of NDVI in spring was consistent with the distribution in autumn, but contrast with the distribution in summer. The time series NDVI in spring and autumn were increased, and the decreased trend in summer was weak. The rate of temperature increasing in spring was the fastest, and the summer followed. The precipitation in spring and autumn were induced, while the precipitation in summer was increased. In the growing season, the vegetation NDVI showed an increasing trend, the temperature increased 0.48 ~C every 10 years （P 〈 0.01 ）, while the trend of precipitation was not obvious. The vegetation NDVI in March, April and November was mainly affected by the temperature. The correlation coefficients between NDVI and temperature of the season and growing season were greater than the correlation coefficients between NDVI and precipitation. The order of the correlation coefficients between NDVI and temperature was： growing season 〉 spring 〉 autumn 〉 summer, while the order of the correlation coefficients between NDVI and precipitation was： spring 〉 growing season 〉 summer 〉 autumn.