Net Primary Productivity (NPP) of Oasis Changes in Trends in Xinjiang and Responses to Climate Change Analysis in 1981-2000

Using the Xinjiang NPP data simulated by GLOPEM from 1981 to 2000, combining with the corresponding meteorological data, vegetation data and LUCC, the spatio-temporal changes of NPP and climate factors in 19812000 were analyzed. The correlation between climate factors and NPP was also analyzed. Finally, the responses of the NPP changes to climate changes were studied. The results showed that, (1) during 1981 and 2000, the annual NPP increased remarkably, the temperature and the precipitation also increased. NPP increased in spring, summer and autumn, but there was spatio-temporal variance between inter-annual changes of NPP and the changes of meteorological variations. (2) the inter-annual changes of NPP and meteorological variations were positively correlated, the growth of NPP was less than that of temperature and precipitation. The year that NPP peaked was not correspondent with the year that the temperature and precipitation peaked, yet the growth rate of NPP lag behind of that of temperature and precipitation slightly. (3) in 1990s, the correlation coefficients between NPP and meteorological variations increased more or less than 1980s. Moreover, the coefficients of the higher vegetation cover types were generally greater than that of the lower vegetation cover types.