Abstract: The evolution characteristics and influencing factors of vegetation coverage in Oasis of Makit County from 1990 to 2020 were analyzed using Landsat series data. The results showed that the vegetation in Oasis of Makit County was generally adjacent to the Yerqiang River and the Tizinapu River. The vegetation coverage from the inside to the outside of the oasis was from the first level to the third level, and the fourth level covered a large area in the west of the oasis. From 1990 to 2020, the total vegetation coverage area, annual average NDVI, and average vegetation coverage in Oasis of Makit County showed an upward trend, and the total vegetation coverage area increased by 199.9 km², with an increase of 12.26%. The absolute spatial variation of vegetation coverage in Oasis of Makit County had the characteristics of temporal and regional differences, both alone and in common. From 2010 to 2020, the area of the first level improvement area of vegetation coverage increased most significantly, which was a typical temporal change; the reclamation area of the 45th Oasis Corps and the northeast of Korma Township had been improved most obviously, and the large-scale degradation around Makit Town was also obvious, which was a typical regional change. From 1990 to 2020, the vegetation coverage intensity and speed in Oasis of Makit County were 0.4%/a and 6.4 km²/a respectively. During the 31 years, except for the overall migration of the fourth level coverage to the southeast, the total vegetation coverage, the first level coverage, the second level coverage and the third level coverage all migrated to the northeast. The increase of cultivated land area in Oasis of Makit County was the main driving force for the increase of oasis vegetation coverage degree, but the increase of cultivated land water demand had squeezed out the ecological irrigation water resources of natural plants in desert oases, leading to the degradation of natural plants, and threatening the harmonious balance of desert oasis ecology.

Key words: Landsat, image subtraction and contrast method, NDVI pixel dichotomy model, vegetation coverage degree, model of plant heart migration, Oasis of Makit County