Nighttime light remote sensing reveals the pattern and process of urbanization evolution in northwest China since the 21st century
Given that Xinjiang Uygur Autonomous Region is a strategic barrier and an important platform of opening up to the western region,assessing its urbanization is critical to promote the national reform strategy and the Belt and Road Initiative.Compared with traditional method,nighttime light(NTL)remote sensing has been proved to be able to monitor human activity intensity and regional comprehensive development level in a more objective,flexible spatial scale and wider coverage.NTL remote sensing data has been able to analyze the urbanization evolution process and the level of social and economic development,but it is still necessary to expand and enrich the breadth and depth of research,especially to explore its spatial pattern and long-term evolution process,so as to more comprehensively understand the urbanization process and social development balance in Xinjiang.This paper comprehensively analyzes and discusses the evolution process of NTL in Xinjiang since the 21st century from three dimensions:time change trend,spatial distribution pattern and social development equilibrium,using NTL remote sensing data of long time series from 2000 to 2020,time series decomposition,spatial standard deviation ellipse and Night Light Development Index(NLDI).(1)From 2000 to 2020,the total amount of NTL in all regions of Xinjiang Uygur Autonomous Region increased to varying degrees.In terms of spatial pattern,urbanization in northern and eastern Xinjiang developed steadily,while rapid development in southern Xinjiang.The planning and construction of transportation lines is one of the important driving forces for the spatial expansion of urbanization in Xinjiang.(2)In the past 20 years,the total amount of NTL in Xinjiang has increased by 5.30 times,and the growth trend is accelerating.The NTL intensity in rural areas of Xinjiang increased by 7.60 times,which was larger than that in urban areas(4.10 times).The process of urbanization in Xinjiang can be divided into three stages:slow development(before 2007),volatile growth(from 2008 to 2014),and rapid development(after 2015).Policy support and the transformation of industrial and agricultural development make Xinjiang's urbanization transition from the slow development period to the volatile growth period.The growth rate of the volatile growth period is nearly three times that of the slow development period,but at the same time,it is also disturbed by various extreme events.(3)From 2000 to 2019,the NLDI in most areas of Xinjiang decreased,the distribution of population and infrastructure construction in the whole region and most cities in Xinjiang became more reasonable,and the social development showed a trend of balanced development.However,compared with urban areas,the balance in rural areas of Xinjiang is weaker.This is due to the low starting point of urbanization development in rural areas of Xinjiang,which is still in the stage of rapid development,and urbanization is undergoing a process of"from point to surface",so the current social development balance in rural areas shows a trend of decline.In general,the urbanization process of Xinjiang has been developing rapidly and evenly since the 21st century.
nighttime light remote sensingurbanization evolutiontime series decompositionNight Light Development IndexXinjiang Uygur Autonomous Region
NETL
NSTL
万方数据
