| Based on five remote sensing datasets of 1995, 2000, 2005, 2010 and 2015 and RS and GIS technologies, Hongsibu district, the largest resettlement center in the nation, was selected as the research object. We used the land use, cultivation index, landscape diversity index, and landscape fragmentation and other indexes to construct an ecological risk index model, then, used the model and spatial analysis method to analyze the temporal and spatial distribution of land use change and its ecological risk in Hongsibu area from 1995 to 2015. The results showed that the area of grassland significantly decreased by 29 494 hm2 during the study period. The land for farming, forestry, water, and construction increased. The construction use increased the most while the unused land fluctuated obviously. From 1995 to 2015, the ecological risk in the study area continued to decline and the ecological risk index decreased from 0.3972 in 1995 to 0.3235 in 2015. The spatial distribution of ecological risk in townships in Hongsibu Ecological Resettlement District varied greatly. However, there was no regularity. These mainly happened between the high risk areas during 1995-2005, and the moderate risk areas and the slight risk areas during 2005-2015. Through the exploration of the ecological risk factors affecting the ecological resettlement area of Hongsibu County by geographical probes, it was found that the index factors such as forestland, grassland, and vegetation coverage had significant impact on the ecological risk in the resettlement area. Therefore, through the Yellow River irrigation project and the construction of basic farmland to increase farmland productivity and ensure the economic development and ecological security of the resettlement areas, attention should be paid to the increase and construction of ecological land area in the resettlement region so it could decrease the vegetation coverage and ecological risk in the resettlement areas. The protecting ecosystem, avoiding poverty, and developing economy are the main directions of eco-migration. Therefore, while Hongsibu resettlement area is pursuing the improvement of economic strength in the development process, it is important to pay attention to ensure the ecological security in the development of the whole region. |