Abstract:Aims We investigated the new and senescent tissues of moss and the soil rhizosphere to determine 1) the elemental and isotopic composition characteristics during senescence and 2) the final contribution to soil. Methods C and N contents and isotopic composition (δ13C andδ15N) of Haplocladium microphyllum and its soil rhizosphere were analyzed at Guiyang, China. Important findings The C and N contents were higher in new growing tissues than in senescent tissues, and there were significant correlations between the two types of tissues, indicating physiological malfunction (e.g., loss of photosynthesis) and internal element redistribution during moss senescence. No significant difference was found between new and senescent tissues in isotopic composition, but theirδ13C values orδ15N values were correlated, suggesting special isotopic regulation in the simple and nonvascular structure of mosses. In contrast, there was no C or N correlation between the moss tissues and soil. This was attributed to long-term nutrient retention and slow deposition to form soil, indicating the moss layer in this area has a small contribution to soil carbon and nitrogen.