Change detection and impact analysis of coastal wetlands in the Shandong Peninsula based on Landsat data

As human societies undergo rapid urbanization, coastal areas have emerged as prominent regions. The concentration of urban populations and the expansion of built-up areas have exerted a significant impact on coastal wetlands, leading to concerns over wetland area shrinkage and degradation, which have become the focal points of academic investigation. This study aims to examine the changes in coastal wetlands on the Shandong Peninsula over the past 30 years using Landsat remote sensing imagery. Additionally, it explores the influence of human activities on these wetlands by employing methods such as the human disturbance intensity index model. The following conclusions have been drawn from the study: (1) Between 1990 and 2020, there was an overall increase in wetland areas, primarily driven by a substantial expansion of constructed wetlands. The rate of increase was significant. However, natural wetlands exhibited a declining trend, with a considerable portion of previously unused land, including natural wetlands, being converted into constructed wetlands. (2) The changes in wetland areas between 1990 and 2020 can be attributed mainly to human activities. (3) Analysis of the development patterns in different cities reveals variations in the impact of human activities on wetland areas. It is evident that the influence of human activities on coastal wetlands differs among various cities.