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Understanding the factors that regulate the functioning of our ecosystems in response to environmental changes can help to maintain the stable provisioning of ecosystem services to mankind. This is especially relevant given the increased variability of environmental conditions due to human activities. In particular, maintaining a stable production and plant biomass during the growing season (intra‐annual stability) despite pervasive and directional changes in temperature and precipitation through time can help to secure food supply to wild animals, livestock, and humans. Here, we conducted a 29‐year field observational study in a temperate grassland to explore how the intra‐annual stability of primary productivity is influenced by biotic and abiotic variables through time. We found that intra‐annual precipitation variability in the growing season indirectly influenced the community intra‐annual biomass stability by its negative effect on intra‐annual species asynchrony. While the intra‐annual temperature variability in the growing season indirectly altered community intra‐annual biomass stability through affecting the intra‐annual species richness. At the same time, although the intra‐annual biomass stability of the dominant species and the dominant functional group were insensitive to climate variability, they also promoted the stable community biomass to a certain extent. Our results indicate that ongoing intra‐annual climate variability affects community intra‐annual biomass stability in the temperate grassland, which has important theoretical significance for us to take active measures to deal with climate change. [ABSTRACT FROM AUTHOR]

Overgrazing has caused serious grassland soil deterioration and significant soil organic carbon (SOC) losses. Controlled grazing is recommended for restoring grassland and enhancing SOC stocks. Studies have suggested that, in particular, labile organic carbon (C) is a sensitive indicator for soil degradation and SOC recovery, but few studies of the effect of different grassland management practices have been published so far. Here, we investigate the effects of long‐term grazing exclusion and short‐term rotational grazing with different grazing intensities on labile SOC, including hot water extractable organic C (HWEC) and particulate organic C (POC), as well as potential N mineralization (Nmin) rate in soils (0–10 cm) of two grasslands in Xilinhot, Inner Mongolia. Treatments include long‐term (34 years) exclusion, medium‐term (21 years) exclusion and continuous grazing (ambient grazing) at one of the sites, and we investigate no grazing, light grazing, moderate grazing and high‐grazing intensity at the study site for rotational grazing. Our results show that grazing exclusion significantly enhances labile SOC stocks and potential Nmin rate compared to ambient grazing (e.g., POC stock at long‐ and medium‐term exclusion and ambient grazing are 5.71 ± 0.94 Mg C ha−1, 3.25 ± 0.30 Mg C ha−1 and 2.12 ± 0.38 Mg C ha−1, respectively). However, after two decades of exclusion, the potential for further C sequestration is limited. Five years of rotational grazing significantly enhances HWEC, but not POC and potential Nmin rate, when comparing the highest grazing intensity (1.88 sheep ha−1 yr−1) with grazing exclusion during the same period. We conclude that rotational grazing may be a viable alternative to exclusion, offering a more rational use of grassland without causing soil C loss. We also show that HWEC is a particularly sensitive labile SOC indicator and is tightly correlated to POC and potential Nmin rate. Highlights: We investigated effects of grazing exclusion and rotational grazing on labile soil organic carbon.Grazing exclusion increased labile SOC and the highest level appeared in medium‐term exclusion.Five years of high‐intensity rotational grazing increased HWEC with no significant effects on POC.Rotational grazing is a viable alternative to grazing exclusion management. [ABSTRACT FROM AUTHOR]