Analysis of Land Use/Cover Change and Landscape Pattern in the Yellow River Delta During 1986-2016

In this study, the Yellow River Delta was used as a research area to obtain land use/cover change data from 1986, 1996, 2006 and 2016 by interpreting Landsat images, and using the trajectory model and landscape pattern index to analyze land use/cover change structure, spatio-temporal characteristics and landscape pattern in the Yellow River Delta for nearly 30 years. The results showed that the area of cultivated land, artificial water, construction land increased, and the area of unused land, forest, grassland and natural water surface decreased in the Yellow River Delta from 1996 to 2016. Among them, the area of unused land was reduced by 2 072.75 km², with the largest change. The increase rate of artificial water, construction land and cultivated land continued to slow down; Grassland and natural water increased slowly during 1986-1996, and continued to decrease after 1996; Forest and unused land showed a rapid decrease trend in all 3 periods. The area of human induced trajectories accounting for 56.13% of the total land area in the Yellow River Delta. The main types are changed to cultivated land and artificial water, which mainly distributed on both sides of the river and strips on land side of the tidal flats. The area of natural trajectories accounting for 15.80% of the total land area of the study area. The main types are changed to sea, grassland and natural water surface, which mainly distributed in the northern and eastern coastal areas. 28.07% of land use/cover types in the study area remained unchanged. The landscape fragmentation, agglomeration degree and structural complexity of human induced trajectories in the Yellow River Delta are higher than the natural trajectories. Human activities play a leading role in the land use/cover change process in the study area. This study can provide a certain reference value for development, management and protection of land resources in the Yellow River Delta.