黄河三角洲景观格局变化及生态风险评价

黄河三角洲具有极高的生态价值，研究其景观格局及生态风险对促进黄河三角洲高质量发展具有重要意义。本文以黄河三角洲1980年、2000年和2020年土地利用数据为基础，分析土地转移及景观格局特征，同时构建生态风险评价模型揭示生态风险时空演变及空间相关性。结果表明：(1)耕地是黄河三角洲最主要的地类，占比在60%以上，1980—2020年土地转移主要发生在耕地、建设用地、水域和未利用地之间。(2)1980—2020年黄河三角洲景观斑块数、景观斑块密度、景观最大斑块指数、景观形状指数和香农多样性指数均呈下降趋势，区域整体趋向简单化和聚集化。(3)黄河三角洲高风险区和较高风险区主要环渤海分布，1980—2020年各级风险区转出最大面积均为更低级风险区，生态风险有所降低。

Landscape Pattern Change and Ecological Risk Assessment in the Yellow River Delta

The Yellow River Delta has very high ecological value. It is of great significance to study landscape pattern and ecological risk for promoting high quality development of the Yellow River Delta. Based on land use data in the Yellow River Delta in 1980, 2000 and 2020, characteristics of land transfer and landscape pattern have been analyzed, and an ecological risk assessment model has been constructed to reveal spatio-temporal evolution and spatial correlation of ecological risks. It is showed that: arable land is the main type of land in the Yellow River Delta, and accounts for more than 60%. From 1980 to 2020, land transfer are mainly construction using land, water area and unused land. From 1980 to 2020, the number of landscape patches, the density of landscape patches, the largest landscape patch index, the landscape shape index, and the Shannon diversity index of the Yellow River Delta are in a downward trend, and the overall area tends to be simplified and clustered. The high risk areas and high risk areas in the Yellow River Delta are mainly distributed around the Bohai Sea.