摘要
The relationships between the normalized difference vegetation index(NDVI)(1981-2006) in growing season and precipitation, NDVI and mean temperature(T_(mean)), NDVI and maximum temperature(T_(max)), NDVI and minimum temperature(T_(min)), and NDVI and the Palmer Drought Severity Index(PDSI) were analyzed. The results indicated that NDVI during the growing season was mostly positively and significantly correlated with precipitation last month and the month before last, and mostly negatively with temperature. There were negative and significant correlation between NDVI in June and July and T_(mean)and T_(max)in May respectively, between April NDVI and T_(min)in February and March, and between June NDVI and T_(min)in April, May and June. Vegetation cover in growing season correlated positively with PDSI, especially those last month and the month before last at 0.05 significance level, even 0.01 level. Hydrothermal conditions from March to July had significant influence on vegetation cover.
The relationships between the normalized difference vegetation index(NDVI)(1981-2006) in growing season and precipitation, NDVI and mean temperature(T_(mean)), NDVI and maximum temperature(T_(max)), NDVI and minimum temperature(T_(min)), and NDVI and the Palmer Drought Severity Index(PDSI) were analyzed. The results indicated that NDVI during the growing season was mostly positively and significantly correlated with precipitation last month and the month before last, and mostly negatively with temperature. There were negative and significant correlation between NDVI in June and July and T_(mean)and T_(max)in May respectively, between April NDVI and T_(min)in February and March, and between June NDVI and T_(min)in April, May and June. Vegetation cover in growing season correlated positively with PDSI, especially those last month and the month before last at 0.05 significance level, even 0.01 level. Hydrothermal conditions from March to July had significant influence on vegetation cover.
基金
Supported by the Science and Technology Plan Projects of Hebei Province(15454201D)