Ecosystem Health Evaluation Based On The Landscape Pattern Evolution Of The Qinling Mountains

Qinling Mountains is the ancestral vein of the Chinese nation and a momentous symbol of Chinese culture,and the Chinese central tower.As a considerable geographical line of demarcation between the north and the south of China,the Qinling Mountains play many important functions such as adjusting the climate,water and soil conservation,water conservation and maintaining biodiversity.Recently,with the prompt development of urbanization and the extend of industrialization,the health of the ecosystem has been seriously affected by human activities in the Qinling Mountains,leading to some social problems such as the ecological degradation.In addition,the prominent contradiction between human and land,which has acutely threatened the sustainable development of social economy.Based on the land use data of the third phase of Qinling Mountains in 2000,2010 and2020,the study analyzed the change of landscape type area by Arc GIS10.2.The software Fragstats 4.2 was used to calculate the landscape index of Qinling Mountains and analyze the change characteristics of landscape patterns in the three periods.On this basis,Qinling counties(cities,districts)were selected as evaluation units,and 15 indicators were selected based on the PSR model.The analytic hierarchy process was used to assign weights to the indicators,and the comprehensive index calculates the results of the ecosystem health of each county and city in the Qinling Mountains in different periods.In addition,the temporal and spatial changes of Qinling's ecosystem health from 2000 to 2020 were summarized,the correlation between Qinling's landscape pattern and ecosystem health was analyzed,and suggestions for Qinling's ecological protection were put forward based on the evaluation results.The principle conclusions of the study are as follow:(1)The area of woodlands and cultivated land take up more than 92%,while the area of the other four land types accounted for a relatively small proportion.There is a lot of woodland and cultivated land,accounting for more than 92% of the total area,followed by grassland,building land,water body and unused land.There is a little change of forest land;The building land was majorly distributed in the northern and southern foothills of Qinling Mountains,and it had doubled in the past 20 years.Moreover,affected by the policy of returning farmland to forest in 1999,the cultivated land area decreased obviously from 2000 to 2020,and the water body increased obviously.(2)In 2000,2010 and 2020,most areas in Qinling Mountains were healthy areas,followed by sub-healthy areas,a few general areas and sub-pathological areas,and no pathological areas.(3)There is a positive correlation between spreading index,patch number,maximum patch index,boundary density and ecosystem health.The other four landscape pattern indexes show a negative correlation with ecosystem health.In general,the landscape index has a greater correlation with the results of ecosystem health evaluation.By studying the change process of Qinling landscape area,we summarized the temporal and spatial laws of Qinling landscape pattern evolution,which can provide a better reference for Qinling ecosystem health assessment.In addition,the evaluation results can objectively reflect the health status of the ecosystems of counties and cities to a certain extent,provide reference for the Qinling environmental management department,and can provide reference for the protection of similar areas of ecosystem health research.