Carbon dioxide fluxes of cyanobacterial crusts and underlying soil under different precipitation patterns in the Ulan Buh Desert, China

Cyanobacterial crusts, sensitive to changes in the moisture content, are widely distributed Ulan Buh Desert. Changes precipitation patterns due global climate change expected influence carbon emission and photosynthetic fixation of soil areas covered with cyanobacterial crusts. We assessed how amount frequency affect processes Crusts. Taking average August during past 30 years as control, we established nine (three amounts × three frequencies). The net flux (NCF) dark respiration rate (DRR) crusts underlying were investigated. Precipitation could stimulate NCF DRR immediately. With increasing water application times, peak values NCF, 12 h cumulative emissions gradually decreased. Both significantly affected but without an interactive effect. Under same frequency, increased amounts. total amount, caused by high-frequency events highest, followed those low-frequency control. However, such changes, against background a changing climate, will result Soil, suggesting that cyanobacteria should be considered projections future budget.