Study On Ecosystem Health Assessment Based On Landuse/Landcover Changes Of Tianjin

With the development of industrial civilization,human disturbance has se-verely affected the ecosystem.In this study,I took ecosystem services as metrics,establishes an index system to assess the health of ecosystem of Tianjin based on landuse and landcover changes,and provides new ideas and suggestions for environmental protection of Tianjin.The spatio-temporal changes of land use were first studied in this paper,the structural changes and rate of change of various landuse types in Tianjin of each year were quantitatively analyzed,then the landuse transfer matrix was used to study the spatial transfer characteristics of landuse types,and uses the landscape pattern index to quantitatively describe the dynamic changes of the landscape pattern.The results show that the overall structure of landuse in Tianjin is stable.Cropland is the most important landuse type,and the urban is the main landuse type with the fastest increase rate.As for landuse transfer,it shows that other landuse types are transferring to urban,and water are transferring to other land types.The process of urbanization makes the landscape more integrated and more concentrated.Secondly,the evaluation of ecosystem services of Tianjin was carried out,and the In VEST model was used to estimate the ecosystem services of soil erosion,water yield and carbon storage.This paper analyzed the characteristics of temporal and spatial changes,explored the changes of Tianjin’s ecosystem service and evaluated current status of ecosystem services of Tianjin.The results show that the amount of soil erosion is larger in the north and smaller in the south.The overall amount of soil erosion declined in the beginning and then increased.The amount of soil erosion in 2020 is6.6×10~6 tons.The water yield is high in the middle of the area and low in the round.The water yield in 2020 is 1.644.1 billion m~3.Carbon storage in the western region is larger than that in the southeast coastal region.The carbon storage in Tianjin has reached more than 9×10~8t during the study period,which is relatively stable.Finally,based on the previous research results,suitable metrics are selected from aspects of pressure-state-response to construct the assessment index system of ecosystem health,and quantitatively assess the ecosystem health of Tianjin.Also,the geodetector is used to explore the driving factors of the ecosystem health changes of Tianjin based on the R language platform,and provide scientific suggestions for the environmental protection of Tianjin.The results show that the ecosystem health index ranges from 0.193 to 0.697.The index in the central,western,northern,and eastern coastal areas are lower than that in the southern and northern central-eastern.The analysis of regional change trends shows that the central and central-northern regions are deteriorating,and the northeastern and southern regions are significantly improving.The driving analysis results show that the secondary industry GDP and population density are always the two most influential factors.The health level of ecosystem of Tianjin is determined by multiple influencing factors.In summary,based on landuse and landcover changes,the changes in soil erosion,water production,and carbon storage ecosystem services in Tianjin were assessed,and an index system to evaluate the health of the ecosystem in Tianjin was established,also,the driving mechanism was explored.The results can provide a scientific basis for ecological system protection and sustainable development in Tianjin.