1986—2016年黄河三角洲土地利用/覆被变化及景观格局分析

基于Landsat影像获取1986年、1996年、2006年和2016年的土地利用/覆被变化数据，使用变化轨迹模型和景观格局指数研究黄河三角洲近30年土地利用/覆被结构变化、变化轨迹时空特征及景观格局。结果表明：1996—2016年黄河三角洲耕地、人工水体、建设用地面积呈增加趋势，未利用地、林地、草地和天然水体面积减少，其中未利用地面积减少2 072.75 km²，变化幅度最大。人工水体、建设用地及耕地的增加速度不断减缓；草地和天然水体于1986—1996年缓慢增加，1996年后持续减少；林地、未利用地在3个时段均呈快速减少趋势。“人为因素”驱动轨迹面积占研究区总面积的56.13%，主要类型变化为耕地与人工水体，分布在河流两侧和滩涂向陆一侧；“自然因素”驱动轨迹占比15.80%，主要类型为变化为海域、草地和天然水体，集中分布在北部和东部沿海地区；研究区28.07%的土地利用/覆被类型未发生变化。黄河三角洲“人为因素”驱动轨迹的景观破碎度、集聚程度和结构复杂程度均高于“自然因素”驱动轨迹，人类活动在研究区土地利用/覆被变化过程中起主导作用。该研究结果可为黄河三角洲土地资源开发、管理与保护提供参考。

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.