Effects of grazing on litter decomposition in two alpine meadow on the eastern Qinghai-Tibet Plateau

Abstract

Litter decomposition is an important component of nutrient cycling and carbon decomposition in grassland ecosystems, and livestock grazing has been a major human intervention to these process. The effects of grazing on litter decomposition vary with climate environment conditions and grassland vegetation types. Alpine mesophytic meadow and alpine semi鄄hydric marsh meadow are the two rangeland ecosystems commonly seen on the eastern Qinghai鄄Tibet Plateau, which differentiate themselves by not only the physic / bio environments but also the plant species composition and therefore the litter qualities. In order to understand grazing effects on the litter decomposition of these two meadows, grazed and fenced plots were set respectively on the both meadows. The rates of decomposition and nutrient release were measured for the three littler samples (mesophytic meadow mixed litter, Deschampsia caespitos litter, and Potentilla anserine litter)

Microbial carbohydrate-active enzymes influence soil carbon by regulating the of plant- and fungal-derived biomass decomposition in plateau peat wetlands under differing water conditions

“… Wiedermann et al (2017) concluded that the plant communities in the sample sites were dominated by Rhododendron and other mycorrhizal woody shrubs and trees, and that at low water, Rhododendron mycorrhizae might reduce the action of hydrolases by limiting the positive effects of increased oxygen on decomposition. In contrast, our sampling sites were all sedge grasslands, which are plants mainly in the gramineae and sedge family as the establishment species, in which cellulose, hemicellulose, and other plant biomass content is higher ( Zhang et al, 2012 ), and the degradation of plant-derived degradative enzymes is stronger under drought conditions, which in turn increases the degradation of soil organic carbon ( Moorcroft et al, 2008 ). This shows that water conditions can regulate soil organic carbon degradation processes by affecting carbohydrate- active enzymes related to the degradation of plant-derived biomass, and further emphasizes the importance of plant-derived biomass decomposition in regulating carbon cycling in plateau peatland ecosystems.…”