Study on Three-Dimensional Configuration Restoration of Biological Crust and Herbaceous Plants on Loess SlopeCN
Abstract：China’s urbanization and infrastructure construction have caused a large number of new bare slopes.Without effective governance,it will have a huge negative impact on the ecological environment.These exposed wounds usually have poor site conditions that traditional plant measurements are difficult to implement directly and achieve the desired results.Artificially constructing biocrusts is a new ecological restoration method,which has the advantages of low cost and quick effect,and can significantly improve the surface soil properties and provide favorable conditions for the establishment of high-grade vascular plants.Based on the previous results of our research group,this study combined biological crusts with grass plants,added different microorganisms,and designs three factors for complete experiments.Experiments were carried out on artificially simulated 45°loess slopes to explore the ecological restoration effects of different treatments,in order to provide new method for the application of biocrusts and the development of slope ecological restoration techniques.The main conclusions are as follows:(1)Grass significantly increased the coverage and thickness of the biocrusts,and its effect of coverage increased with the incubation time.Functional microbes had a significant effect on the coverage and moss height of the biocrusts,and had no significant effect on the biocrusts thickness.But after 90 days of cultivation,the effect of functional microbes on biocrusts coverage became insignificant.At the end of the cultivation,treatment Grass had the largest crust coverage,reaching 87.50%;treatment Grass+BMu(Grass+Bacillus mucilaginous)had largest thickness and moss height of2.87 mm,1.87 mm respectively.(2)Biocrusts promoted the growth and development of grass.It significantly improved the grass coverage,plant height,biomass and relative water content.Functional microbes significantly increased grass coverage at the beginning of cultivation.After cultivation,treatment BSCs had largest grass coverage of 33.97%;the height,aboveground biomass of grass under treatment BSCs+BMe(biocrusts+Bacillus megaterium)were the best,which were 41.97 cm and 30.95 g/m~2,respectively.(3)Biocrusts,grass and microorganisms all significantly improved soil anti-erodibility.Biocrusts had the greatest impact on soil water stability index.In the study,the water stability index of treatments that had biocrusts were significantly greater than those without biocrusts.Treatment BSCs+Grass+BMe had the best effect and its water stability index was 3.38.(4)At the end of cultivation,treatment BSCs+Grass+BMu had the maximum of biocrusts thickness,moss height and the coverage and aboveground moisture of grass,which were 2.87 mm,1.87 mm,33.63%and 75.89%,respectively.Treatment BSCs+Grass+BMe had the maximum of grass aboveground biomass and soil water stability index,which were 30.95 g/m~2 and 3.38,respectively.The configuration of biocrusts+grass+microorganisms achieved the best slope ecological restoration effect,and maximize the soil anti-erodibility of the surface soil.