Abstract: Taking the roadside from Lotus Pond to the main peak of Yanshan Mountain in Wuling Mountain Nature Reserve as a case site, the impact of road construction on the roadside vegetations was studied by investigating the vegetation composition, coverage, biomass, and plant density. Due to road disturbance, the trees along the road decreased in number but their seedlings appeared, while the biomass, species richness index, and diversity index of herbs were higher. With the increasing distance from road shoulder, the plant biodiversity decreased, but the density, height, and diameter at breast height of trees increased. The composition of shrub-grass was constant when the distance from the road shoulder increased over 30 m, and the structure of tree layer had no change when the distance from the road shoulder was over 150 m. The impact of road construction on the vegetations was mainly positive on shrubs and herbage but mainly negative on trees, and the positive impact was larger than the negative impact. The impact on the species richness of plant communities was greater on the upslope than on the downslope of the road.

Key words: Ecological model, Sensitivity analysis, Local sensitivity analysis, Global sensitivity analysis, Spatially explicit landscape model