Land Use Change And Ecological Quality Assessment Research Of Xiong'an New Area Based On Remote Sensing

The core driving force for the change of regional ecological environment is mainly the change of land use type.With the continuous acceleration of urbanization and industrialization and the increasing population.The interference of human activities has caused major changes in the structure and quantity of the original land types.This led to a series of changes in water resources,soil,vegetation,biodiversity and climate within the ecosystem,which ultimately led to a deterioration in regional ecological quality.Basing on the ENVI and GIS software platform,this paper interpreted the status of land use in Xiong'an New Area in 1995,2004 and 2015,and extracted the normalized vegetation index(NDVI),wet index(WET),land surface temperature(LST)and normalized difference building soil index(NDBSI)from the aspects of greenness,humidity,heat and dryness,using principal component analysis technology to integrate selected indicators to evaluate the ecological quality in the same period.Finally,the paper studied the transfer law of land use type change in different ecological quality change level areas,and systematically analyzed the impact of regional land use change on the spatial and temporal differentiation of regional ecological environment quality.The main research conclusions were:(1)In the past 20 years,the change of land use type in Xiong'an New Area showed obvious“two increase and four decrease”in terms of area quantity.And the increase land was construction land and cultivated land,the decrease land was water area,unused land,garden land and forest land.The construction land and cultivated land area increased by117.14 km~2 and 12.28km~2 respectively,and the reduced areas of water,unused land,forest land and garden were 62.54 km~2,30.12 km~2,12.05 km~2 and 24.39 km~2 respectively.From the perspective of land structure transformation,the most important type of land use was cultivated land,accounting for more than 54%of the total land area;waters and construction land are closely followed.The land area of these two types of land over the years is between 10%and 20%of the total land area,and the area and proportion of unused land,gardens and woodlands were relatively small.From the perspective of the direction of land transfer,the study area was mainly transferred from waters and unused land,and is mainly transferred to construction land,mainly through the conversion of cultivated land.(2)The average RSEI values of the Xiong'an New Area in 1995,2004 and 2015 were0.724,0.710 and 0.682 respectively,and the overall trend was decreasing year by year,indicating that the ecological quality of the study area gradually deteriorated.The main reason was the occupation of cultivated land and the sharp decline of the water area of Baiyangdian Lake in the continuous urbanization construction.From the analysis of the change structure,the study area mainly changed from excellent and good grades to medium,poor and poor grades,which showed that urbanization construction was more destructive to areas with better ecological quality,and less impact on areas with poor ecological quality.The three-year average correlation coefficient between RSEI and each component index was higher than the three-year average correlation coefficient between any component indicators,which indicated that RSEI can better integrate the information of each component index and comprehensively and accurately reflect the ecological quality of the study area.(3)Through the research on the transfer matrix of various types of RSEI under different types of change,it was found that a large area of cultivated land was converted into construction land in the area with reduced ecological quality.Comparing with cultivated land and water area,construction land had a greater negative impact on the ecological environment.On the contrary,in the area where the RSEI value is increased,it was mainly through the reclamation of construction land and the conversion of water area into cultivated land.The large-scale transfer of cultivated land and water area had increased the surface vegetation coverage and water conservation function of the area,which had positively affected the regional ecological environment.(4)From the RSEI spatial distribution law and the land type conversion law of each ecological quality change level,it can be found that the regional ecological quality change was closely related to the urban expansion and had a negative correlation.Therefore,in order to improve the ecological environment of Xiong'an New Area in the future,it is necessary to integrate more ecological concepts into the planning and construction of the new district and increase the protection of Baiyangdian.The results of this study are intended to provide a targeted reference for the environmental protection and governance of the Xiong'an New Area,and to guide the future economic development and industrial structure planning.