Mini-patches are considered indicators of an ecosystem’s response to interference, particularly those in alpine meadow ecosystems. Thus, monitoring the characteristics of mini-patches can elucidate the organization of an ecosystem’s components, the strategies it employs to survive interference, and the mechanisms whereby it maintains stability. In this research, we used multivariate statistical analysis methods to investigate the characteristics of the plant community and the micro-topography of mini-patches in alpine meadows on the Qinghai-Tibet Plateau from August 2012 to August 2013. Our findings show that (1) mini-patches were distributed in alpine meadows with different levels of degradation and the effects of meteorological characteristics (accumulated temperature above 0°C and accumulation of precipitation) and geographical characteristics (altitude, longitude, and latitude) contributed less than 20% to their distribution and characteristics; (2) alpine meadows maintained aboveground biomass within a certain range under a relative larger range of grazing intensity, illustrating their ability to regulate community structure and components under various intensities of disturbance and showing that alpine degradation could itself counteract grazing disturbance; and (3) overgrazing is the main driver of multi-steady stage coexistence in alpine meadows, as the mini-patches that remain involved in plant community succession function, and as a source of germplasm in the plant community regime shift under different grazing intensities damaged alpine meadows.

Alpine wetlands play a sensitive function in global carbon cycle during the ongoing climate warming, yet the temporal patterns of carbon dynamics from in situ ground-based long-term observations remains unclear. Here, we analyzed the continuous net ecosystem CO2 exchange (NEE) measured with the eddy covariance technique over an alpine peatland on the northeastern Qinghai-Tibetan Plateau from 2007 to 2016. The wetland acted as a net CO2 source with a positive NEE (120.4 ± 34.8 gCm-2year-1, Mean ± S.D.), with the mean annual gross primary productivity (GPP) of 500.3 ± 59.4 gCm-2year-1 and annual ecosystem respiration (RES) of 620.7 ± 74.2 gCm-2year-1. At the seasonal scale, the classification and regression trees (CART) analysis showed that aggregated growing season degree days (GDD) was the predominant determinant on variations in monthly NEE and monthly GPP. Variations in monthly RES were determined by soil temperature (Ts). Furthermore, non-growing season Ts had a significant positive correlation with the following year annual GPP (p<0.05). Non-growing season RES only accounted for about 25% of annual RES, but had significant correlation with annual RES and annual NEE (p<0.05). The further partial correlation analysis showed that non-growing season air temperature (Ta, p = 0.05), rather than precipitation (PPT, p = 0.25) was a predominant determinant on variations in annual NEE. Our results highlighted the importance in carbon dynamics of climate fluctuations and CO2 emission from the non-growing season in alpine wetlands. We speculated that the vast peadlands would positively feedback to climate change on the Tibetan plateau where the non-growing season warming was significant.