Abstract: The dry-hot valley of Jinsha River region is one of the most ecologically fragile regions in China. Understanding land-use landscape patterns in this region has great significance for regional ecological and environmental regulation. Based on land-use data of four periods in 2005, 2010, 2015, and 2020, as well as the GIS spatial ana-lysis and landscape pattern analysis methods, we investigated the landscape pattern and topographic effect of land use with different elevation ranges, slope categories and topographic position indices. The aims of this study were to reveal the driving mechanisms of land-use landscape pattern change and provide a scientific basis for regional ecological regulation and control. The results showed that the degree of land-use landscape fragmentation was strengthened from 2005 to 2020, landscape heterogeneity was obvious, landscape diversity was increased, and landscape evenness was improved. Woodland, grassland and arable land were landscape substrates of the study area. The main landscape types of dry-hot zone were grassland and arable land, with a significant growth in area of waters and construction land. The main landscape types in the non-dry-hot zone were woodland and grassland, with a continuous decrease of arable land area and a constant increase of construction land area. The distribution trend of slope and topographic position of various land-use types were almost the same. Arable land, water area, and construction land were mainly distributed in low terrain, while woodland, grassland, and unused land were primarily distributed in middle and high terrain. There was an obvious topographic effect of land-use landscape patterns in the study area. Natural factors drove the basic pattern of land-use landscape in the study area. The impacts of human factors on regional land-use landscape pattern had been strengthened during the past 15 years, while the effects of human factors had become more obvious after 2015. In the future, more research about landscape pattern in the dry-hot valley of the Jinsha River should be done on the construction of regional landscape ecological security pattern and response characteristics and mechanism of regional land-use landscape pattern to global climate change.

Key words: Jinsha River, dry-hot valley, land use, landscape pattern, topographic effect, human interference.