Relationship of population migration, crop production pattern, and socioeconomic development: evidence from the early 21st century

Abstract

Global crop production and population distributions have undergone great changes under climate change and socioeconomic development, and have drawn considerable public attention. How to explain the similarity of the migration patterns of crop yield and population density for different countries/regions is still uncertain and worth studying. Here, we estimated the similarity between migrations of main crop caloric yield (i.e. maize, rice, wheat, and soybean) and population density using Fréchet distance, and investigated the regression relationship between Fréchet distance and related climatic and socioeconomic variables for countries/regions with different economic development stages. The results indicated that different countries/regions showed different Fréchet distances during 2000–2015, with a maximum value of 24.44 for Russia and a minimum value of 0.11 for Georgia. For countries/regions with different economic development stages, the built regression models can explain 39%–93% of the variability in the Fréchet distance. Log(land area), log(GDP), and log(land area under cereal production) were always included in regression models and had higher importance in explaining the variability of Fréchet distance. For the model for all countries/regions, both the log(land area) and log(GDP per capita) may positively link to the Fréchet distance. Possible reasons for these results are that countries/regions with high GDP (or GDP per capita) may ease the conflict of land resources between humans and crops to achieve agricultural industrialization, which causes the far connection of the migrations for crop caloric yield and population density. The complicated interactions of crop production, population dynamic, and socioeconomic development should be given greater attention in the future.