Moss biocrusts physiological index.xlsx

We studied the effect of the litter covering on biocrust-forming mosses on the northern Chinese Loess Plateau over four-month period. We used litter from shrubs of Artemisia ordosica and Caragana korshinskii with two levels of litter “thickness”, and monitored moss greenness, and several indicators of moss physiological activity.We found litter covering reduced moss greenness, content of chlorophyll a and b, soluble sugar, and soluble protein, suggesting a reduced photosynthetic and metabolic activity of mosses under litter cover. On the other hand, mosses covered by litter showed higher contents of malondialdehyde, proline, and catalase activity compared to those mosses without any litter cover, suggesting that litter covering increased oxidative stress in mosses and triggered a protective response against oxidative damage. These results demonstrated the detrimental effects of litter covering on biocrust-forming mosses’ physiological activity. Moreover, we found litter thickness exerted a more significant impact than litter type.