Analysis of the characteristics and influential factors of the evolution of cropland in the Yangtze River Delta since the mid-seventeenth century
Background,aim,and scope Cropland is an important covariate for studying the change of land utilization change and environmental change in historical periods,and quantitative reconstruction of cropland change has been a core issue in international LUCC research.Since the implementation of land policies during the Kangxi period of the Qing Dynasty in the mid-seventeenth century,the rate of change of cropland in the region of the Yangtze River Delta(YRD)has accelerated significantly,having exerted a great impact on the modern socio—economic—environmental situation.This study aims to analyze the evolution-oriented pattern of arable land in the historical period and explore the coupling process and mechanism between regional environmental changes and human activities,with a view to providing scientific references for the construction of ecological civilization and sustainable development in the YRD.Materials and methods Based on previous studies,this paper systematically collects data on cropland in the YRD since the 17th century,selects influential factors such as elevation,slope,soil as well as distance from rivers and population density,conducts binary logistic regression by using SPSS software,and combines the weight of influential factors on the distribution of cropland in different periods to reconstruct data on the evolution of cultivated land in the YRD from 1661 to 2020,based on which the spatial differentiation pattern and temporal evolution process of historical cropland are explored and the driving factors of cropland change in different periods are systematically analyzed.Results The amount of cropland in the YRD shows an M-shaped fluctuating upward trend,and its spatial distribution is marked by"more in the north and less in the south",with the spatial pattern evolving in a"west-to-north expansion and further diffusion".The spatial pattern is featured by"westward and northward expansion".During the Qing Dynasty,the natural geographical environment was an important factor affecting the spatial distribution of cropland.Agricultural policies and technologies gradually became the main reason for changes in cropland along with social development.After the Reform and Opening Up,the accelerated industrialization and urbanization process and the promotion of ecological fallowing projects led to continuous reduction of cropland in the YRD.Discussion The cropland pattern of the YRD in the historical period has been under continuous influence of geographic and environmental factors,showing the characteristics of dynamic changes.In the process of geographic change and the evolution of the cropland pattern,the natural geographic environment influences the formation and evolution of the cropland pattern at the macro-level,which is always the base of the deduction and change regarding the cropland pattern,and also the foundation of the regional human landscape.The human geographic environment,on the other hand,changes the pattern of cropland in depth and in detail at the micro-level,and the change of land utilization not only reflects the practice of human development of nature,but also reflects the philosophical thought of human-land relationship.Conclusions The change of cropland in the YRD reflects the game between humans and natural geography,and the change of the concept of"human-land relationship".The plan of regional development should highlight the ecological advantages of the YRD,create an integrated regional ecological landscape corridor,and promote the construction of ecological civilization and beautiful China under the guidance of sustainable development.Recommendations and perspectives Future research is required to quantify human and social factors such as agricultural policies and farming techniques to improve the model of historical cropland reconstruction.
historic croplandhuman-land relationshipYRDsustainable development