Study On The Evaluation And Prediction Of Urban Wetland Ecological Security

As an important component of the urban ecosystem,urban wetlands are facing problems such as shrinking wetland areas,decreasing biodiversity and serious pollution of waters due to external interference from regional socio-economic development and human activities,based on which it is crucial to evaluate and study the ecological safety of urban wetlands.This study takes a typical urban wetland,Baqiao Wetland Ecological Park,as the research object.Through field survey sampling,remote sensing monitoring and model construction,the current ecological safety situation and landscape pattern condition of this wetland are studied,and based on the results of the current situation study,the DPSR model is used to construct an urban wetland ecological safety evaluation system for The ecological safety condition of the study area from 2017 to 2021 was evaluated,and finally the GM(1,1)model was used to predict the future safety condition of the study area,and the following conclusions were drawn:(1)The site monitoring results of Baqiao Ecological Wetland Park show that the water quality of the wetland is between Class Ⅲ and Ⅴ water throughout the year,which is a mild eutrophication level,and the water quality pollution of the water body at the entrance and exit of the wetland park is more serious;the heavy metal pollution of the wetland soil is more serious,with some sample points exceeding the standard for clement Ni,element As reaching a moderate pollution level,and the biological effectiveness of element Cd is high,posing a greater threat to the soil ecology;the organic pollution of the wetland sediment is at a cleaner and still clean level,and the organic nitrogen content is high,which is a pollution level.(2)Based on the analysis of remote sensing image data,the water area of Baqiao Ecological Wetland Park shows a decreasing trend from 2017 to 2022,the vegetation cover shows a "W"type fluctuation trend,and the wetland landscape types are rich but unevenly distributed spatially,and the patches arc fragmented due to the influence of human activities.(3)The results of the evaluation of the ecological safety of urban wetlands show that the ecological safety index of wetlands in the study area shows a fluctuating trend of decreasing and then increasing from 201 7 to 2021,with the ecological safety status of wetlands decreasing from critical safety to moderate warning from 2017 to 2019 and recovering from moderate warning to critical safety from 2019 to 2021.Among them,the fragmentation of the landscape and the increase in urban population are important influencing factors leading to the threat of wetland ecological safety,but since 2019,with the emphasis on environmental protection and the promotion of wetland-related policies reduce the risk of wetland ecological safety.(4)Based on the grey prediction GM(1,1)model to predict the ecological safety status of wetlands in the study area,it is concluded that the ecological safety index of this wetland climbs year by year,and the area returns to a safer state by 2025 and to a safe state by 2028,with the safety index of pressure,state and response system all showing an increasing trend and the driving force system showing a decreasing trend.