摘要
Dear Editor,Biological soil crusts(BSCs),a layered structure formed by associations of soil organisms and topsoil,dominate arid and semiarid areas and serve important ecological functions in these areas(Eldridge and Greene,1994).Nitrogen fixation by BSCs is the main source of N in arid and semi-arid ecosystems.Desiccation is the most notable factor that influences BSCs,which recover physiological activity only after moistening.By influencing the amount of carbohydrates,
Dear Editor, Biological soil crusts （BSCs）, a layered structure formed by associations of soil organisms and topsoil, dominate arid and semiarid areas and serve important ecological functions in these areas （Eldridge and Greene, 1994）. Nitrogen fixation by BSCs is the main source of N in arid and semi-arid ecosystems. Desiccation is the most notable factor that influ- ences BSCs, which recover physiological activity only after moistening. By influencing the amount of carbohydrates,
基金
supported by the Special Fund for Forest Scientific Research in the Public Welfare of China (201404204-02)
