Abstract: In order to invert the vegetation coverage of the farming-pastoral transition zone by using the Landsat TM/OLI image data of 2006, 2011 and 2016 ,the Gannan county of Heilongjiang province was taken as the study region, based on the RS and GIS technology, the models of normalized difference vegetation index（NDVI） and dimidiate pixel were quantitatively obtained the vegetation coverage of the study area, and the transfer matrix model was used to analyze the temporal and spatial variation characteristics and evolution process of vegetation coverage within 10 years. The results showed that the overall coverage of vegetation cover in the study area was good. The sum of the data coverage and the medium-high coverage area of the three phases in 2006,2011,2016 was 87.29%,87.18% and 87.10%, respectively. In 2006—2011, the vegetation coverage was mainly converted from high coverage and middle coverage to medium and high coverage, and the conversion rates was 76.83% and 55.49%, respectively. In 2011—2016, the conversion between medium and high coverage and high coverage was strong, and the conversion rate was 10.87% and 83.00%, respectively. In the past 10 years, the area ratio of the vegetation change stable area was 64.32% and 65.54%, respectively. 2011—2016 compared with 2006—2011, the area of vegetation degradation decreased by 257 km², while the area of vegetation improvement increased by 199 km², and the vegetation was still dominated by degradation.

Key words: vegetation coverage, farming-pastoral transition zone, spatio-temporal evolution, Gannan county