DIGITAL EXTRACTION AND CHANGE ANALYSIS OF ALTITUDINAL NATURAL ZONES IN TIANSHAN TOMUR NATURAL HERITAGE SITE

Abstract. The Tomur Natural Heritage Site possesses the most typical altitudinal natural zones on the south slope of the Tianshan Mountains. Five altitudinal zones have developed on the south faced slope, including: warm temperate desert zone, mountain steppe zone, alpine meadow zone, alpine cushion vegetation zone and ice-snow zone. The demarcation elevation of the altitudinal natural zones on the south slope was extracted based on surface classification data, DEM and NDVI of the 1992 and 2016 Landsat TM/OLI data. The results showed that the demarcation elevation between the warm temperate desert zone and the mountain steppe zone rose by 6 m, the mountain steppe zone and the alpine meadow zone fell by 25 m, the alpine meadow zone and the alpine cushion vegetation zone moves up by 26 m, and the lower limit of the ice-snow zone rose by 11 m.