Discussion On The Application Of Mucuna Sempervirens In Ecological Restoration Of Rock Slope In Guangxi Highway

With the implementation of the strategy for the development of the western region,the construction of expressways in Guangxi has been developing rapidly.By 2017,5,259 km of expressways have been completed.It is expected that by 2020,the total length of highway planning in Guangxi will exceed 8,000 km.Due to the limited geological conditions of Guangxi and highway technical specifications,a large number of deep excavation and high-filled slopes have formed during the construction of expressways,especially rock slopes which lack the basic conditions for plant growth.The slope vegetation recovery costs are high and the cycle is long.It not only affects the road landscape effect,but also destroys the original ecological balance and may cause geological disasters such as landslides.Therefore,it is particularly important to realize the ecological restoration of rock slopes,and it is also a requirement to adapt to the construction of ecological civilization in the new era..The ecological restoration of rock slope focuses on plant selection.As an excellent urban landscaping plant,Mucuna sempervirens is still a blank in the application of highway landscape in Guangxi.After reviewing the relevant literature and studying the ecological restoration mechanism of rock slopes and the ecological habits of Mucuna sempervirens,the paper carried out greening design and construction,on-site investigation,growth environmental testing and effect evaluation relying on the ecological restoration experiment of the rock slope of the Cenxi-Shuiwen Expressway.The research results are as follows:(1)Through the investigation and analysis of the natural climate,topography and landforms and rock slope characteristics along the Cenxi-Shuiwen Expressway,and combined with the ecological habits of Mucuna sempervirens,it was concluded that Muuna sempervirens is feasible in this area.And the paper also conduct engineering tests on different types of rock slopes.(2)Through on-site surveys and observing the growth conditions and coverage of Mucuna sempervirens on these slopes,the results of the application of Mucuna sempervirens on the slopes were obtained.(3)Soil samples were taken from the site and related experiments were conducted to determine the soil pH,organic matter,nitrogen,phosphorus,potassium,and trace elements in diffident slopes.Combining with the analysis of slope characteristics,this paper summarizes the ecological rehabilitation adaptability of Mucuna sempervirens in rock slopes and the basic conditions for achieving good results.(4)Finally,based on the AHP-fuzzy comprehensive evaluation method,a comprehensive evaluation of the ecological restoration effect of the rock slope of the Cenxi-Shuiwen Expressway was conducted.The evaluation results agreed with the actual situation.Through theoretical research and engineering experiments,the thesis shows that under suitable conditions,Mucuna sempervirens is adapted to the ecological restoration of highway rock slopes in the climate conditions of the southeast of Guangxi.The construction is simple,the management is extensive,and the cost is low.It is worth promoting.