Temporal and spatial analysis of construction land changes in the Yangzonghai basin from 2005 to 2020

As to grasp the quantity of land for construction in the Yangzonghai Basin and analyze its spatiotemporal variation characteristics to alleviate conflicts between human activities and the environment, this research utilized remote sensing image data from 2005, 2010, 2015, and 2020 and using ArcGIS, Fragstats4.2 to employ various analytical methods including , dynamic change degree, assessment of different terrain conditions, transfer matrix analysis, geospatial information charting, and landscape pattern index calculation. The results indicate an increasing trend in the quantity of construction land in the research area from 2005 to 2020, with an increase in area of 809.31hm² and a dynamic change degree of 1.86%. At the county level, apart from Guandu District and Songming County, the other three counties exhibited a consistent increase in construction land over the study periods. Terrain conditions significantly influenced the spatial distribution of construction land, with preference for areas below 2000m in altitude and slopes less than 8° for development. Analysis based on geospatial information atlas and landscape pattern indices revealed fluctuations in construction land over the study period, with predominant changes involving conversions from unused land, forest land, and cultivated land, collectively accounting for about 95% of the changes, with cultivated land having the largest proportion. The amount of land for construction patches decreased from 2005 to 2020, while the average patch size and patch fractal dimension increased, indicating enhanced spatial aggregation and landscape connectivity. This study provides insights into the dynamics of construction land in the Yangzonghai Basin over the past 15 years, aiming to give data support and decision-making basis for village planning and ecological environment protection in the region.