Abstract: In this study,the latest data of GIMMS NDVI 3g plus,MVC,trend analysis,coefficient of variation and partial correlation analysis were used to study the spatial and temporal distribution and change trend of NDVI in the Hoh Xil Natural and Cultural Heritage Reserve in Qinghai Province during the period of 1982-2015 and to analyze the driving factors.The results showed that: ① The NDVI in the study area increased gradually from northwest to southeast due to the change of water and heat conditions caused by altitude; ② During the period of 1982-2015,the NDVI in the study area was in an obvious increase trend,the increase rate of NDVI in the core was 0.69%·(10a)^-1,and it was 0.41%·(10a)^-1 higher than that in the buffer area; ③ The area of the regions with NDVI improvement in the study area was much larger than that with NDVI degeneration,and the NDVI was holistically in a slow increase trend.The areas of the regions with NDVI improvement and NDVI degeneration in the core accounted for 47.92% and 3.00% respectively,65.70% area in the buffer area was basically maintained; ④ The area of the regions with relatively low and moderate NDVI fluctuation in the 34 years accounted for 75.54% of the total,and these regions were mainly distributed in the central and southern parts of the core and most areas of the buffer zone; ⑤ The results of correlation and partial correlation analysis showed that the NDVI in the study area was affected by temperature and precipitation,especially by temperature.

Key words: GIMMS NDVI 3g Plus, trend analysis, partial correlation analysis, Hoh Xil World Natural and Cultural Heritage Reserve