Study On Cultivation And Recovery Of Broadcasting Moss Biocrusts

It is urgent to restore soil surfaces damaged by engineering and other soil disturbing activities,nevertheless,conventional plantings of vascular plants are often unsuitable.Previous work has suggested that the production and establishment of biological soil crusts(biocrusts;a soil surface community of cryptogams and/or microbes)may represent a low-cost solution to erosion control.However,most studies have produced biocrusts under controlled settings,and little is known about methods to establish biocrusts under varying field environmental conditions.In multiple field experiments,we tested the effects off our factors including application of nutrient solutions,a water-retaining agent,a plant growth regulator,and various levels of shading(0,50%,70% and 90%)on growth and establishment of moss-dominated biocrusts,and broadcast dispersal techniques.We monitored dynamic changes in the coverage,density and biomass of moss biocrusts during the cultivation period.The results were as follows:(1)Nutrient solutions had significant impacts on the coverage,plant density and biomass of moss crusts(p<0.05),whereas the plant growth regulator and water retaining agent had no significant impacts on these parameters(p>0.05).In addition,the order of application frequency of plant growth regulators was 0 day>7 day>14day.At the end of the cultivation period,all treatments moss biocrusts cover exceeded 85%,and the maximal plant density of moss biocrusts reached 120 plants/cm2 under broadcast dispersal;(2)The nutrient solutions and some degrees of shading both had extremely significant effect on the coverage,plant density and biomass of moss biocrusts.Simultaneously,the nutrient solutions interacted with shading increased the coverage,plant density and biomass of moss biocrusts.At the end of the cultivation period,the maximal moss biocrusts cover had achieved 78%,and the maximal plant density of moss biocrusts reached 47 plants/cm2 under broadcast dispersal;(3)In general,the cultivation of mosses dispersed in the fall outperformed that of mosses dispersed in the summer.At the end of the cultivation period,the maximal coverage and plant density of moss biocrusts in autumn were 16.5% and 88 /cm2 higher than that in summer.However,compared to autumn,the plant height and biomass of moss biocrusts of summer were more than 1.35 mm and 10.7 ug/cm2,respectively.So the rapid restoration of moss biocrusts can best be achieved by broadcast-seeding in the fall using the nutrient solutions and 70% shade while maintaining soil water content at15-25%.This technique could feasibly be up scaled and adopted to restore some ecological functions on various types of engineered slopes,and other disturbed surfaces.