Screening Of Community Configuration Mode In Xinnan Highway Slope

In this paper,the slope of Xinnan(Xinyang-Nanyang)highway which is crossing the ecological type of the Nanyang basin and the ecological type of the Tongbai mountain is studied.And this paper researches on the present community characteristics of vegetation in Xinnan highway slope.Then establishes a comprehensive evaluation system from four aspects: landscape effect,community growth,soil nutrients and slope stability with survey data,and makes comprehensive evaluation of highway slope with the help of AHP-fuzzy comprehensive evaluation method.It can be concluded that:(1)In the 13 years since the completion of the Xinnan highway since 2004,the ecological restoration of Xinnan highway is very good,the samples are consist of Amorpha fruticosa Linn ? Vitex negundo ? Heterophylla ? Broussonetia papyrifera ? Festuca arundinace?Cynodon dactylon?Imperata cylindrica?Lolium perenne?Dianthus chinensis?Humulus scandens?Euonymus fortunei?Equisetum arvense?Artemisia argyi?Coreopsis drummondii?Chrysanthemum paludosum?Herba Artimisiae Sieversianae?Medicago sativa and other plants.The species composition of the sand filled slope and the sub slope is the most abundant among them.(2)By the analysis of various plant species,life form,community importance and biodiversity data that can be concluded,in Xinnan highway,the evergreen plants are less with single shrub species.And the diversity and richness of species were different among different species,the planting forms of plants are very single which are lack of certain levels of change.But the ecological restoration of the slope has been through a long period of time,and the plant configuration of the community is reference to native plants,and with the strong vitality of Gramineae and Compositae plants with the principle of respecting the nature environment and suitable trees.Therefore,the slope of the community is relatively stable,which can provide a stable ecological protection for highway slope.(3)According to the different content of soil nutrients,the slope of the Xinnan highway can be divided into three categories:The first site is fully weathered rock slope and soil with weak acid or weak alkaline soil and the p H value close to 7 that can conducive to plant growth and development.The soil organic matter,available phosphorus,available potassium and total nitrogen in the first site are the highest in the three sites.Among them,the contents of organic matter,available phosphorus and available potassium were much higher than those of the other 3 sites;The second type of site include sand fill slope and weathered rock slope,The soil is weakly alkaline and the p H value was close to 8.3.And the average value of organic matter,available phosphorus,available potassium and total nitrogen was close to the average of 32 samples;The third type of site is sub clay slope,the organic matter,available phosphorus and total nitrogen were significantly lower than the average value,and the content of organic matter and available phosphorus was only 1/3.Other conditions are relatively poor,is the worst condition of the three types of sites.(4)This paper takes the Xinnan highway K1120 section of Festuca arundinace+Pyracantha fortuneana+ Duchesnea indica community as example to make comprehensive evaluation of the slope Xinnan highway slope based on the AHP-fuzzy comprehensive evaluation model.The evaluation results show that the comprehensive evaluation of the landscape of this sample is "excellent" and among them,the evaluation level of landscape effect and community vegetation is " excellent",the results of slope stability evaluation are "good",and the evaluation results of soil nutrients are " commonly".According to the principle of maximum membership degree concludes that the comprehensive evaluation grade of the slope landscape of Xinnan highway is "good".(5)Based on the AHP-fuzzy comprehensive evaluation model,all the samples of three sites on the Xinnan slope were evaluated and we can sum up that:In the weathered rock+soil of the first type of site,pure herbs: Festuca arundinace+Coreopsis drummondii +Imperata cylindrica with the shrub grass configuration: Vitex negundo +Amorpha fruticosa Linn +Lolium perenne+ Medicago sativa is the most outstanding.In the sand fill slope and weathered rock slope of the second type of site,pure herb configuration: Heaven grass +Euonymus fortunei+ Medicago sativa with two shrub grass configuration: Euonymus fortunei+Coreopsis drummondii +Festuca arundinace+Duchesnea indica,Vitex negundo +Amorpha fruticosa Linn+Festuca arundinace with excellent performance.In the sub clay slope of the third type of site,pure herb configuration: Dianthus chinensis+Euonymus fortunei+Lolium perennewith the shrub grass configuration: Amorpha fruticosa Linn+Lolium perenne+ Imperata cylindrica+Prunella vulgaris with outstanding performance.(6)In view of the present situation of the lack of available phosphorus and available potassium in the soil of the Xinnan highway slope,and the limitation of the maintenance frequency,this paper put forward the corresponding suggestions to improve the allocation of the community,improve the site conditions,into the design of rainwater,raise the level of management to establish the corresponding system,in order to improve the comprehensive quality of the slope landscape,reduce the maintenance cost,alleviate the traffic pollution,improve the ecological service function,and construct the economical and intensive highway.