干旱区生态环境知识资源中心

Interannual changes in temperature and precipitation can profoundly influence plant phenological status such as the date of onset of green-up, the rate of biomass accumulation. and the onset and rate of vegetation senescence. The objective of this study is to examine annual climatic variation, and its influence on plant phenology of the steppes of Inner Mongolia. Variation in the date of onset of green-up was studied using a 9-year dataset of biweekly composites of the maximum Normalized Difference Vegetation Index (NDVI) values (1982-1990). We found little or no change in date of onset of green-up over the 9-year period for forest and cultivated lands. The date of onset of green-up was progressively earlier or later for the typical and desert steppes, and highly variable for the Gobi Desert. Meteorological data (monthly mean temperature and monthly precipitation) indicated a correlation between date of onset of green-up and climate measurements.