An analysis of the spatial evolution and influencing factors of rural settlements along the Shandong section of the Grand Canal of China

Since 1980s, the weakening of the transportation function of the Grand Canal and rapid urbanisation have generated significant changes in the spatial pattern of rural settlements along the Grand Canal. Analysing the changing characteristics of this spatial pattern, and exploring the natural, social, and economic factors influencing these changes are key to understanding the regional spatial structure and development law, and grasping the degree of influence of these factors. This study selected approximately 13,000 rural settlements in 27 county-level units in the Shandong section of the Grand Canal, from 1980 to 2018, as the research object. The Grand Canal's distance buffer zone is divided into canal-side, near-canal, far-canal, and further-canal settlements. The correlation model with the canal is constructed through the controlled experiment. The distribution, scale, and form of the settlement are analysed quantitatively by applying the change of gravity centre model (CGC), average nearest neighbour analysis (ANN), landscape metrics (LM), and other methods. The quantitative analysis of geographic detectors in spatial pattern differentiation factors shows the relative importance and interaction within them. This study indicates that the spatial distribution shows 'large dispersion and small concentration' and 'small-scale agglomeration' characteristics. The larger the scale of the settlement expands, the more the number of settlements decreases. The closer the settlement nears the river, the more complex the shape clusters. The total output value of agriculture, forestry, animal husbandry, fisheries, the total power of agricultural machinery, and the effective irrigation area are the main influencing factors. The grain area and the per capita disposable income of rural residents are the main auxiliary influencing factors.