The evolution of artificial oasis over two millennia in Hexi corridor, China

Artificial oasis is an important geographical unit that is formed by the combination of natural disturbances and human interventions in a fragile ecosystem of arid regions. Therefore, there are important theoretical and practical significance to estimate long term artificial oasis changes and its driving mechanism. We took Hexi Corridor in northwest of China as a case study, based on multi-types of data included documentary reconstruction records, historical archives data and published articles to quantitative analyze the relationship between artificial oasis evolution and a set of natural and human factors over the past two millennia (0-1990 AD). Results showed that artificial oases had a tortuous evolutionary history, experienced three periods of rapid development in the Hexi Corridor. The structural equation model revealed that two human related factors (population density and grain yield) have a significantly greater influence on artificial oasis development than natural variables (temperature). According to current conditions, paradigm shift in human behavior are the prerequisite for oasis evolution and its transition. Furthermore, assessment the scale of artificial oasis based on the human-land relationship is a future direction for research and practice, for allocating water and soil resources rationally, improving the quality of oasis, and controlling the scale of oasis.