Study On The Spatial And Temporal Evolution Of National Human Settlements Ecological Environmental Quality Based On Google Earth Engine Platform

With the rapid progress of urbanization in China,the phenomenon of population increase has presented a trend of urban concentration,and the city has gradually become the main residences of the population.A suitable ecological environment is an ideal goal not only for social development and human pursuit,but also for an important foundation and carrier for sustainable development of the urban economy.Therefore,it is extremely important to analyze the spatiotemporal evolution in terms of the quality of human settlements ecological environmental quality dynamically and explore the driving factors that affect the human settlements ecological environmental quality.However,due to the limitations of traditional technical means and human resources,the assessment of human settlements ecological environmental quality is still not deep enough in view of the spatial analysis and driving force mining.Therefore,it is of great importance to study the law of temporal and spatial evolution of human settlements ecological environmental quality.With the help of powerful cloud computing capabilities of Google Earth Engine platform and using 30 meter Landsat data over 2000 to 2018 as the main data source,this article establish a long-term human settlements ecological environmental quality evaluation model,which integrates natural elements,meteorological elements,human activities elements and terrain elements.Meanwhile,the geographical zoning concept is introduced to explore the main driving factors which impact the quality of the human settlements ecological environment from the perspective of multiple levels and multiple spatial scales.The specific research contents are as follows.(1)A long-term national human settlements ecological environmental quality evolution model is constructed by using particle swarm optimization algorithm,coefficient of variation method and decision-making trial and evaluation laboratory method.The correlation between the model results and the total ecological footprint and ecological carrying capacity in China are 0.823 and 0.820,respectively,and the reliability of the model is high.From the perspective of time development,the changes are accessed in the view of the quality of human settlements ecological environment in China on a long-term sequence.The results demonstrate that although the quality of human settlement ecological environment in China shows an approximately linear upward trend with significant fluctuations,and the suitability of human settlements has gradually improved.From the perspective of spatial pattern,through the introduction of Hu Line,it is found that the quality of human settlements ecological environment in the southeast of Hu Line is better than that in the northwest of Hu Line.In addition,the quality of human settlements in Central South,East China,Northeast China and southwest China is higher than the national average,while the quality of human settlements in North China and Northwest China is lower than the national average.(2)The concept of geographical zoning is introduced to explore the main driving factors from the two spatial patterns of the national scale and the six geographic zonings scale.Results show that the index elements explain the quality of human settlements in a geographical region with a high degree of geographic similarity higher than the country's unit due to the effect of spatial heterogeneity.In addition,we use geographic detectors to explore the impact of the interaction of dual-index elements on the quality of human settlements.Results show that no matter under the national scale or the geographical region scale,the influence of the interaction of the two index elements on the quality of the urban ecological environment is much higher than the effect of the single index element,and the correlation coefficient is up to 0.5.By analyzing the influence of socio-economic and human activities on the quality of human settlements,the results show that population is the main driving factor which affects the ecological environmental quality of human settlements in China,with the correlation of up to 0.97.(3)In the study of eco-environment quality of human settlements in typical regions of the Yangtze River Economic Zone,it shows that from 2000 to 2018,the quality of human settlements in Chengdu,Chongqing,Wuhan,Hangzhou,Hefei and Kunming has an obvious upward trend,and the living adaptability of the area is gradually increasing.In Nanchang,Nanjing and Changsha,there is no obvious upward trend in the quality of human settlement ecological environment,while the quality of human settlement ecological environment in Shanghai is basically flat.The correlation between NDVI index and the human settlements ecological environmental quality in Chengdu,Changsha and Nanjing shows a decreasing trend,while the correlation between wetness index and the human settlements ecological environmental quality in Chengdu,Changsha and Nanjing shows an increasing trend.Taking the Yangtze River economic Zone as a whole,it is found that the slope index is negatively correlated with it.The quality of human settlements ecological environment in the upstream city Chengdu is negatively correlated with the slope index,while the quality of human settlements ecological environment in the downstream city Nanjing is positively correlated with the slope index.The paper includes 43 figures,25 tables and 121 references.