| A large number of rock slopes were produced owing to the open-pit mining in mining areas,which has caused serious harm to the ecosystem of mining areas.It not only caused the geological disasters such as soil erosion and landslide,but also leaded to the ecosystem fragmentation and biodiversity reduction.The different ecological restoration materials and plant seeds were sprayed on the surface of rock slope to construct the artificial ecosystem for ecological restoration of rock slope.The ecological restoration project of rock slope in Xishan mining area of Taiyuan was the research object,and the correlation characteristics between different slope gradient and slope position,plant diversity,physical and chemical properties of artificial soil and microbial community were studied.Canonical correspondence analysis(CCA)and redundancy analysis(RDA)were used to study the relationship between environmental factors and plant distribution in order to provide the theoretical basis for ecological restoration of rock slope.The results showed that:(1)In this study,seven rock slope samples were selected and divided into slope Ⅰ(40°～ 50°),slope Ⅱ(50° ～ 60°)and slope Ⅲ(60° ～ 70°).There were 35 species in the rock slope plant community,belonging to 11 families and 29 genera.The plant community of slope Ⅰwas abundant and had a good recovery effect.There were 35 species of plants,belonging to9 families and 27 genera,including Leguminosae,Compositae and Gramineae.In the ecological restoration process of rock slope,slope gradient and slope position had the significant effects on the plant diversity.The plant diversity index of slope Ⅰ was higher than that of rock slope Ⅱ and slope Ⅲ.There were the significant differences between the plant richness index,Shannon index and Simpson index at different slope positions(P < 0.05).(2)There were the significant differences between soil bulk density and soil moisture at the different slopes(P < 0.05),there were no significant difference between different slope positions.The contents of available potassium,alkali-hydrolyzed nitrogen,available phosphorus and organic matter in different positions of the same slope showed the trend of middle slope > lower slope > upper slope.The average organic matter content(29.5 mg/kg)and total nitrogen content(13.8 mg/kg)of artificial soil of rock slope Ⅱ were significantly higher than those of other rock slopes(P < 0.05).(3)The bacterial community Chao1 index and Shannon index of slope Ⅰ and slope Ⅱwere significantly higher than those of slope Ⅲ,the richness index of slope Ⅲ was significantly higher than that of the other two slopes,the Chao1 index of middle slope Ⅲwas significantly higher than that of upper slope,and the Simpson index of upper slope Ⅲwas significantly higher than that of middle slope Ⅲ(P < 0.05).Simpson index of bacterial community and fungal community of slope Ⅲ was significantly higher than that of slope Ⅰand slope Ⅱ.The Simpson index of the fungi community in the middle slope of slope Ⅰ was significantly higher than that in the upper slope.The dominant flora of bacterial and fungal communities under different engineering conditions were consistent at phylum and class levels,and the relative abundance of each flora was not significantly different.The bacterial community network connectivity of slope Ⅰ and Ⅱ were higher than that of fungal community network of slope Ⅰ.(4)The results of CCA analysis showed that the soil moisture content,bulk density,soil clay and pH played an important role in plant growth.The results of RDA analysis showed that the organic matter,soil moisture content and available phosphorus were important factors affecting microbial distribution.On the whole,the vegetation restoration of rock slope were most affected by soil water content,alkali-hydrolyzed nitrogen,clay and pH. |
PDF Full Text Request