Effects of Biological Crust on Soil Properties under Different Karst Rocky Desertification Habitats

Abstract

Biological crust is an important type of surface cover in karst ecosystems and plays a key role in the restoration of rocky desertification and ecological control projects. It is very important to study the influence of different types of biological crust on the physical and chemical properties of subsoil under different levels of rocky desertification to explore the formation and development of soil in karst ecologically fragile areas and the stability of soil environment. In the crust layer, total nitrogen, available nitrogen, total phosphorus, available phosphorus, available k, soil organic carbon, soil field capacity and soil porosity manifest as moss crusts>mixed biocrust>lichen biocrust>algae biocrust (P<0.05), while soil bulk density manifests as algal crust>lichen crust≥mixed crust≥mossy crust (P>0.05). The physical and chemical properties of 0-5 cm and 5-10 cm soil layers on the subcutaneous surface of biological nodules are similar to those of the crust laye. biological crusts have an impact on the improvement of physical and chemical properties of the underlying soil in the latent, mild and moderate-intense rocky desertification areas, that is the moss crust and mixed crust are greater than lichen crust and algae crust and the influence of different types of biological crust on the physical and chemical properties of the underlying soil decreases with the deepening of the soil layer. Besides pH value, soil physical and chemical properties (total nitrogen, available nitrogen, available potassium, total phosphorus, available phosphorus, soil organic carbon, soil bulk density, soil field capacity, soil porosity and available potassium) of different types of BSCs are significantly correlated. Biological crust is a good prerequisite for the growth and development of vegetation as it can significantly improve the physical and chemical properties of soil, increase soil nutrient content, promote the formation of soil aggregates, enhance the bearing capacity and anti erosion capacity of land, and balance the stability of soil environment. Therefore, it is of great significance to study the mechanism of biological crust on soil physical and chemical properties improvement and the interaction mechanism between biological

Responses of Soil C, N, P and Enzyme Activities to Biological Soil Crusts in China: A Meta-Analysis

“…The curve is a fitting curve obtained by Gaussian equation fitting; Figure S2: Funnel plot of logarithmic response ratio of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP) content and Alkaline Phosphatase, Cellulase, Sucrase, Urease activity to biological crust, funnel plot effect value (natural logarithm of response ratio, lnR , horizontal axis) and standard error ( SE , vertical axis); Table S1: The overall heterogeneity ( Q T ) of the response of each explanatory variable to the biological crust, the percentage of heterogeneity caused by the real variation between the effect sizes ( I 2 ), and the heterogeneity between groups ( Q B ); Table S2: Kendall’s tau rank correlation tests for assessing publication bias; Table S3: Rosenthal’s fail-safe numbers for assessing publication bias; Table S4: The results of weighted regression analysis of the effect values ( lnR ) of response variables with annual average temperature, annual average rainfall and altitude; Table S5: Meta-analysis of initial data. References [ 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 ,…”