Abstract:

The study of landscape pattern evolution is an important way to understand regional ecological security and sustainable development. This study uses Landsat series remote sensing images from 2000 to 2020, combined with Fragstats 4.2 software to calculate landscape pattern indices. It also employs methods such as the transfer matrix and geographic detector to systematically reveal the spatiotemporal evolution characteristics and driving mechanisms of the landscape pattern in Chengjiang City. The results show that: 1) From 2000 to 2020, the land coverage types in Chengjiang City were dominated by cultivated land and forest land. Over the 20‑year period, the cultivated land area has decreased by 6.54 km², most of which was converted to grassland and forest. The forest area increased by 36.81 km², mainly from cultivated land, while the construction land area increased by 5.15 km², mainly from cultivated land and forest land. 2) Between 2000 and 2020, the degree of landscape fragmentation in Chengjiang City intensified, with both the Contagion Index and Shannon's Diversity index showing upward trends, indicating that human activities have led to increased landscape heterogeneity. This study validates the applicability of Fragstats in landscape analysis of plateau lake areas and provides data support for the land space optimization and ecological protection in Chengjiang City.

Key words: landscape ecology, landscape pattern, landscape index, drive, Chengjiang City