Understanding land use volatility and agglomeration in northern Southeast Asia.

Land use change has generally been considered a cause and consequence of environmental change. Here, we interpreted the land cover in northern Southeast Asia (including parts of Myanmar, Thailand, Laos, Vietnam and China) year by year from 2000 to 2018 with the Google Earth Engine (GEE) platform. The results show that the areas of old growth forest, young growth forest and annual crops have changed dramatically in the study area. The average frequency of land use change was determined to be 5.4 times (that is, the land use changed every 3.4 years) by comparing the land use types in each year throughout the entire study period, and the frequency of land use change showed a significant agglomeration effect. In addition, there was a substantial difference between the land use change determined with an annual approach and that determined with the commonly used time-stage approach; time-stage land use change studies may overlook gradual change processes in land use change, which highlights the necessary of determining a suitable time period for studying land use change at the local scale. The results show that understanding land use volatility and agglomeration has become important to deepen the understanding of land use change and to help formulate land use policy.