Background Grazing has important influences on the structures and functions of grassland ecosystems, but the effects of grazing patterns on grassland biomass and soil environments in China remain unclear. Objective We employed a meta-analysis to identify the response of biomass and soil environments to different grazing patterns in China. Methods Peer-reviewed journal articles were searched using the Web of Science and China National Knowledge to compile a database. A total of 1011 sets of sample observations satisfied the sampling standards; these were derived from 140 study sites and were obtained from 86 published articles. We conducted random effects meta-analyses and calculated correlation coefficients with corresponding 95% confidence intervals. Results Grazing significantly decreased the total biomass, aboveground biomass (AGB), belowground biomass (BGB), soil organic matter, soil total nitrogen, soil total phosphorus and soil water content but increased the root-to-shoot ratio, soil available nitrogen, soil pH and bulk density. Generally, increasing grazing intensity and duration significantly increased the effects of grazing on the biomass and soil environment. Additionally, the smallest effects of grazing on the biomass and soil environments were observed under light grazing and cattle grazing alone. Moreover, non-growing season grazing significantly increased AGB, while annual grazing and growing-season grazing significantly reduced AGB. Furthermore, AGB was positively correlated with soil organic matter, soil available phosphorus and bulk density, while BGB was negatively correlated with pH. Conclusions These findings highlight the importance of grazing patterns in the biomass and soil environment response to grazing and suggest that cattle grazing alone and grazing during the non-growing season are beneficial for improving the quality of grassland in China.

The influence of paleoclimate on the depositional process of lacustrine mudstone and organic matter accumulation is important to both paleoclimate reconstruction and hydrocarbon exploration. Here we study the lower third Member (Es3L) of the Eocene Shahejie Formation in the Zhanhua Depression, Bohai Bay Basin, eastern China in order to understand how paleoclimate influenced depositional processes and organic matter accumulation of lacustrine organic-rich mudstone. By combining detailed core descriptions and microscopic observations, and high-resolution mineralogical and geochemical analyses, we identified two major lithofacies, including massive calcareous mudstone and laminated calcareous mudstone, from the Luo 69 drilling core. The sedimentologic observations and changes of geochemical proxies, including detritus index, Ln(Al2O3/Na2O), B/Ga, and V/(V+Ni), suggest that the massive calcareous mudstone was deposited in a small, shallow, salt lake that was dysoxic-anoxic, and the paleoclimate in the lake catchment was cool and arid, and the laminated calcareous mudstone was deposited in a large and deep stratified lake, which has anoxic, highly saline bottom and oxic, less saline surface water, and the lake catchment was more humid and warm. The dominant lithofacies changed from laminated calcareous mudstone to massive calcareous mudstone in the studied core, suggesting that the lake became shallower and smaller when the paleoclimate 3 became cooler and drier through time. Such a climate trend may be a response to global cooling during the middle Eocene. The average total organic content (TOC) in both lacustrine highstand and lowstand are comparable even though the lake water chemistry and amount of terrigenous input are different. We infer that the accumulation of organic matter within the lacustrine highstand was controlled by the combination of primary productivity, carbonate production, and preservation in anoxic bottom water, while accumulation within lacustrine lowstand was only controlled by primary productivity.

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