Nutrient cycling is a key ecosystem function whereby the processes of litter decomposition and N release in the soil-plant interface are vitally important but still not clear in the alpine ecosystems. We carried out a 3-year study to improve our understandings in nutrient cycle and develop strategies for restoring the degraded grasslands on the Qinghai-Tibetan Plateau. We established the grazing (GP) and grazing exclusion paddocks (GEP), then identified litter species composition and analyzed litter and soil chemical characteristics. Litter decomposition and N release were monitored by incubating litter <q>in situ</q> and across paddocks over 799 days. We found that grazing did not change plant species composition, but increased litter N; while grazing exclusion increased litter mass of palatable species and promoted soil organic carbon. Litter decomposed faster in GP, while N release was faster in GEP. Incubation site environment had more but litter source had less impact on litter decomposition and N release. Therefore, grazing and grazing exclusion had different impacts on litter decomposition and N release but both elevated nutrient cycle. The implications of our findings in restoring the degraded grasslands on the Qinghai-Tibetan Plateau were discussed.
Sun, Y., He, X. Z., Hou, F., Wang, Z., & Chang, S. (2018). Grazing elevates litter decomposition but slows nitrogen release in an alpine meadow. Biogeosciences Discussions, 1–35. https://doi.org/10.5194/bg-2018-66