信南高速公路边坡景观评价方法与群落选择

A Method of Landscape Evaluation and Selection of Vegetation Community in Xinyang-Nanyang Expressway Slope

针对信南高速公路边坡群落适应性差,生产力低下,景观效果不佳的问题,对公路边坡景观予以综合评价,用以指导该区域路域边坡界面的建设。采用聚类分析法,依据不同边坡的土壤养分将信南高速公路的边坡划分为A全风化岩+生土,B填砂边坡与风化岩,C亚黏土3类立地;再借助AHP法对3类立地,共计32个样方进行综合评价,从景观效果、生态效益与土壤养分3个方面建立评价模型并确定权重系数,进而对不同群落的边坡景观现状进行评价。结果表明,第1类立地中的优势群落为紫穗槐+构树+高羊茅+紫花苜蓿;第2类立地中的优势群落为紫穗槐+构树+高羊茅+黑麦草与紫穗槐+黑麦草+小叶扶芳藤;第3类立地中的优势群落为紫穗槐+石竹+高羊茅(或黑麦草)+金鸡菊或小叶扶芳藤+石竹+黑麦草+高羊茅。

Aiming at the problem of the poor slope vegetation community adaptability, low productivity and poor landscape effect in Xinyang - Nanyang expressway, the landscape of expressway slope is evaluated comprehensively to guide the construction of the regional road slope interface. By using clustering analysis method, and based on the soil nutrient of different slopes, the Xinyang -Nanyang expressway slope is divided with 3 types of site： A fully weathered rock ＋ raw soil, B sand slope and weathered rock, C sub clay. Then with the help of AHP, a comprehensive evaluation for the 3 types of site is made, a total of 32 sample plots, and an evaluation model is established and the weight coefficient is determined from the aspects of landscape effect, ecological benefit and soil nutrient, and the slope landscape status of different vegetation communities is evaluated. The result shows that （1） the dominant community in the first site is amorpha fruticosa ＋ broussonetia papyrifera ＋ tall fescue ＋ alfalfa; （2） the dominant community in the second is amorpha fruticosa ＋ broussonetia papyrifera ＋ tall fescue ＋ ryegrass and amorpha fruticosa ＋ ryegrass ＋ euonymus fortunei var. radicans ; （ 3 ） the dominant community in the third site is amorpha fruticosa ＋ dianthus chinensis L ＋ tall fescue （or ryegrass） ＋ coreopsis or euonymus fortunei var. radicans ＋ dianthus chinensis L ＋ ryegrass ＋ tall fescue.