By exploring the spatial-temporal pattern changes of ecological land in Yangzonghai watershed of Yunnan Province, this paper obtained the quantity and spatial distribution of ecological land, which promoted the effective protection, rational utilization and sustainable development of ecological environment in the watershed. Using the data of 2005, 2010, 2015 and 2020, ArcGIS and Fragstats4.2 software were used to analyze the spatial and temporal patterns of ecological land use in the study area by using dynamic variation degree, transfer matrix and landscape pattern index. The ecological land in Yangzonghai watershed was mainly basic ecological land and auxiliary ecological land, which accounted for about 77% of the total study area. From 2005 to 2020, the ecological land showed a decreasing trend, with a total decrease of 798.61 hm2. From the perspective of ecological land transfer matrix, forest land, cultivated land, bare land and construction land are converted frequently. The increase of forest land was mainly from cultivated land and bare land. The sources of cultivated land increase were forest land and bare land. The increasing sources of construction land were cultivated land, bare land and forest land. The decreasing sources of forest land became bare land and cultivated land. The decreasing sources of cultivated land became forestland and construction land. According to the landscape pattern index, woodland, water area and farmland were the main landscape types in the study area. From 2005 to 2020, woodland, water area and cultivated land all showed a trend of fragmentation, and the patch geometry changed from simple to complex. However, on the whole, the connectivity of dominant patch types in the study area was good, and the landscape diversity and dominance were relatively stable although there were certain fluctuations. The quantity, transfer and landscape pattern of ecological land in Yangzonghai basin from 2005 to 2020 were analyzed. It is expected to provide data support and decision-making basis for ecological land protection and ecological security system construction in the watershed.

【Objective】In order to grasp the quantity of cultivated land in Yangzonghai basin, the temporal and spatial variation characteristics of cultivated land were analyzed, which could provide a reference basis for the sustainable utilization of cultivated land resources and land spatial planning in Yangzonghai basin. 【Method】Based on ArcGIS, Fragstats 4.2 and other software, the RS data from 2005, 2010, 2015 and 2020 were selected to analyze the dynamic variation and spatial distribution pattern of cultivated land in the study area using different methods such as dynamic variation degree, different terrain conditions, transition matrix, geo-informatic atlas, and landscape pattern index. 【Result】From 2005 to 2020, the number of cultivated lands in the study area showed a decreasing trend with a reduced area of 816.45hm2 and a dynamic variation degree of -0.66%. From the county (district) scale, Yiliang County showed a continuous decline trend in the past 15 years, while the other three counties (districts) increased and decreased in each period; The topographic conditions had a certain impact on the cultivated land spatial distribution. The cultivated land in the study area occupies a large proportion in the cloudy aspect and semi-cloudy aspect with the altitude < 2300m and slope < 25°; From the perspective of geo-informatic atlas and landscape pattern index, cultivated land increased and decreased in each period from 2005 to 2020. The main types of land increasing are forest land, unused land and construction land, among which forest land accounted for a large proportion, indicating that the local ecological protection measures such as "returning farmland to forest" had achieved certain results. The landscape pattern index changed in each period from 2005 to 2020. Throughout the 15 years, the number of cultivated land patches had increased, and the average patch area and aggregation degree had decreased, indicating that the overall spatial aggregation of landscape pattern had weakened, the trend of landscape fragmentation had been presented. 【Conclusion】Based on the RS data of 2005, 2010, 2015 and 2020, the spatial distribution pattern changes of cultivated land in Yangzonghai basin in recent 15 years were analyzed from different angles by using the methods of dynamic variation degree, different topographic conditions, transfer matrix, geo-informatic atlas and landscape pattern index, so as to provide an important basis for rural revitalization and village planning in the future.