Preliminary study on the relationship between temporal and spatial evolution of ecological landscape pattern and climate change in Xinjiang, China

Fractional vegetation cover data (FVC) based on the annual maximum NOAA/AVHRR NDVI (Advanced Very High Resolution Radiometer normalized difference vegetation index) data and the ground meteorological data have been used to analyze the relationship between the temporal and spatial evolution of ecological landscape pattern and climate change in Xinjiang autonomous region, China from 1982 to 1993. It is found that during this period, the averaged oasis cropland or low-damp forest-shrub meadow area occupies 7.50% of the whole region, desert dune/barren desert 25.70%; temperate semi-arbor desert 21.70%; temperate shrub and semi-shrub desert 8.36%; alpine subalpine desert steppe 7.71%; temperate gramineous and ruderal steppe 7.63%; mountain forest steppe 2.13%; high-cold barren 8.93%; high-cold low semi-shrub desert 9.08%; water/ice 1.26%. Compared with the 30-year (1961-1990) climatology, the 12-year averaged annual surface air temperature and precipitation over the whole region increase by 0.28 degreesC and 23.6 mm respectively. The maximum increase of precipitation does not occur over the mountain region; instead it occurs over the region with a concentrated distribution of oases, suggesting the positive role of oases in adjusting regional climate. The area of temporal steppe also increases with the increase of precipitation and temperature. Together, these results demonstrate that, during the 12-year period, the condition of vegetation cover has been improved and large-scale desertification does not occur in Xinjiang.