The alpine grassland on the Qinghai-Tibetan Plateau has long been subjected to grazing by local livestock, yak, and Tibetan sheep. The alpine grassland grazing ecosystem provides vital ecological services for the region and fundamental living supports (economic services) for the local residents. However, grassland degradation due to artificial disturbance (over-grazing) and climate change has resulted in profound losses of both ecological and economic services of the alpine grassland. In order to explore the most sustainable grazing management, we have conducted a series of manipulated grazing experiments to evaluate the impact of different grazing systems on the structure and functions of the alpine grassland. The experiments involve grazing intensity, annual/seasonal grazing regime, and different livestock species (yak and Tibetan sheep) under moderate grazing. The results showed that: (1) Grazing intensity dramatically influenced species composition and community structure; (2) Heavy grazing intensity not only decreased community biomass but also reduced forage quality because of the loss of palatable grasses and augmentation of weeds; (3) The seasonal grazing regime had less effect on plant composition when compared to continuous grazing; (4) The structure of the plant community was relatively stable under moderate grazing irrespective of livestock species; (5) Yak grazing increased soil total carbon (STC) but decreased soil total phosphorus (STP), whereas sheep grazing decreased STC but increased STP, and neither of the two livestock species had an impact on STN.
Audio/Video, Conference Presentation, SER2019
Pre-approved for CECs under SER's CERP program
Society for Ecological Restoration