[Effects of biological crusts on soil organic carbon in sandlands under a precipitation gradient].

Biological crusts (Biocrusts) are important surface active coverings in arid and semi-arid regions, which affect the content of soil organic carbon (SOC), SOC labile fractions and stability of SOC through photosynthetic carbon fixation. At present, studies on the variation characteristics of SOC, SOC labile fractions and the stability of SOC in biocrusts are rather limited. In this study, two types of typical biocrusts (moss crusts and algae crusts) were selected along a precipitation gradient from northwest to southeast in the Mu Us Sandland (straight line distance 188 km) by measuring soil organic carbon (SOC), soil microbial biomass carbon (MBC), water soluble carbon (DOC), particulate carbon (POC), easily oxidizable carbon (ROC).

[Spatial distribution and the influencing factors of organic carbon of biological crusts on regional scale in Mu Us sandy land, China].

As an important soil cover in deserts, biological crusts play a central role in ecosystem function such as nutrient cycling, nitrogen fixation, and carbon sequestration. Many biological crust organisms could fix CO through photosynthesis to improve soil organic carbon content. There is a knowledge gap in the origin of soil organic carbon (SOC) from biological crusts on a regional level, which restricts the prediction of soil carbon pool.