Ecological Risk Warning And Multi-development Scenario Simulation Of Complex Environmental Roads In Mountainous Areas

The road network responsible for goods transportation and information exchange is not only a catalyst promoting social development but also a disruptor affecting the speed and direction of surrounding land use/cover changes that facilitate mountain development.How to quantitatively identify the threshold of road ecological risk,intelligently warn the future evolution trend,and realize the predictability and control of road ecological risk warning under multiple development scenarios has become the key to alleviate the contradiction between road development and complex ecological environment protection in mountainous areas.Here,we aimed to(1)analyze the evolutionary trend of future road ecological risks and(2)quantify the threshold of the road ecological risk.To achieve these research purposes,first,we comprehensively built a road ecological risk assessment index system using three components:the hazard of risk sources,the loss degree of receptors and the vulnerability of the risk environment.Second,we measured the range of road ecological risk threshold to explore the range of road ecological risk radiation under different levels of road development,using the ecological risk assessment model and distance attenuation theory.Third,we coupled the system dynamics model-FLUS model-mathematical statistics model,and set three development scenarios of investment priority,harmonious development and ecological protection to classify the ecological risk of complex environmental roads in mountainous areas and simulate multiple development scenarios.In this way,we can explore the optimal path of ecological development,analyze the spatial and temporal evolution characteristics of road ecological risk,and simulate the evolution trend in different development situations in the future.Our research summarizes the spatial and temporal differences of road ecological risk driven by complex factors,the impact threshold of different levels of roads and the future evolution trend under multiple development scenarios.These research results could provide a reference for road ecological risk monitoring and control and promote the coordinated development of mountainous road transport infrastructure and ecological spaces.(1)From 2015 to 2020,the stability of the road ecological risk in Chongqing increased year by year,while the risk value further increased.The fluctuation value of the risk source hazard increased from 0.6701 to 0.7368.The degree of receptor loss decreased from 0.3107 to 0.3092.The vulnerability of the ecological environment decreased from0.5170 to 0.4826.Road ecological risk as a whole evolves to high risk level.The proportion of the serious-,high-,medium-,and light-alert areas increased from 0.34%,6.36%,22.12%and 39.96%in 2015 to 0.55%,17.00%,27.19%and 40.46%in 2020.(2)Different levels of road networks had different degrees of influence on the radiation range of ecological risk.Ecological risk thresholds of national road,expressway,provincial road and county road had increased from 5.17km,2.48km,2.35km and 3.67km in 2015 to 10.33km,2.16km,2.23km and 3.04km in 2020.(3)From 2020 to 2030,the overall road ecological risk in Chongqing showed an upward trend.Among them,the proportion of no-alert risk level area decreased by16.42%,the proportion of light-alert area decreased by 0.50%,the proportion of medium-alert area decreased by 5.07%,the proportion of high-alert area increased by 10.64%,and the proportion of serious-alert area increased by 0.21%.(4)The differences in development scenarios result in significant differences in road ecological risks.In 2030,under the investment priority scenario,the road ecological risk level is dominated by serious-alert(49894.39km~2)and high-alert(29436.55km~2),followed by medium-alert(2152.69km~2),light-alert(494.00km2),and no-alert(90.10km~2).Under the harmonious development scenario,the road ecological risk level is medium-alert(21432.49km~2)and high-alert(27837.02km~2),followed by light-alert(14101.25km~2)and serious-alert(16831.84km~2),and no-alert(2188.08km~2)is the lowest.Under the ecological protection scenario,the road ecological risk level is medium-alert(19815.83km~2)and high-alert(29055.42km~2),followed by light-alert(11196.27km~2)and serious-alert(18410.28km~2),and no-alert(3912.77km~2)is the lowest.