An assessment of the factors that drive changes in the distribution and area of cultivated land in the Yellow River Delta, China

摘要

The Yellow River Delta is an important land expansion and cultivated land reserve area, where the relationship between land use and the landscape is constantly evolving with changes in the area and morphology of the large river delta. Furthermore, it is also an ecologically fragile area where the relationship between environmental and socioeconomic factors needs to be carefully managed, particularly in the cultivated land area, which is important to local livelihoods. Consequently, it is important to understand how the distribution and area of cultivated land on the delta have changed over time and to identify the key factors that have influenced the changes in this land use in the region. In this paper, a comprehensive method of trajectory analysis and geodetector models was used, with the cultivated land evolution trajectory from 1990 to 2018 as the dependent variable. Based on the multitemporal Landsat TM/OLI remote sensing images of the Yellow River Delta and socioeconomic data, a geodetector assessment was applied to analyze the pattern of change in the cultivated land and its influencing factors during a 30-year period. The results of this analysis have shown that the amount of cultivated land in the Yellow River Delta first increased and then decreased slightly. Most cultivated land was derived from unused land, forest and grassland, and most cultivated land was then converted to construction land. The cultivated land loss has mostly taken place on the margins of tidal flats and in the areas surrounding towns. The amount of cultivated land has been expanding, largely following the distribution of urban expansion. A geodetector analysis showed that socioeconomic factors were the main factors that drove the changes in the distribution of cultivated land in the region. These factors, including the gross national product, proportion of primary industry, and rate of population change, were the main driving factors for cultivated land expansion. The proportion of primary industry, proportion of secondary industry, and distance from the coastline were the main influencing factors for the loss of cultivated land.