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A new foraminiferal fauna is reported from the upper part of the Xiala Formation in the Zhari Namco section in the central Lhasa Block, which contains three species of fusulines and 26 species of small foraminifers. The presence of Reichelina and Codonofusiella in the fauna suggests a Wuchiapingian age. A review of the Lopingian faunas in several localities in the Lhasa Block indicates that this block was under a shallow marine environment during the Lopingian, rather than an uplifted terrestrial environment as previously recognized. The Lopingian palaeobiogeography as well as the sequences of the Lhasa Block differs greatly from the adjacent South Qiangtang, Karakorum and South Pamir blocks, and the Tethys Himalaya region of the Indian Plate. It further suggests that the Lhasa Block was separated from the South Qiangtang Block in the north by the Bangong‐Nujiang Ocean and the Tethys Himalaya area in the south by the Neotethys Ocean during the Lopingian time. Furthermore, the dissimilarity of the Guadalupian and Lopingian strata and faunas between the Lhasa and Karakorum blocks and similarity between the Lhasa and Tengchong blocks, may suggest that the Lhasa and Tengchong blocks were linked together during the Permian. [ABSTRACT FROM AUTHOR]

Small burrowing herbivores create extensive disturbances to grassland soil, which may change carbon cycling. We focused on the plateau pika (Ochotona curzoniae) to simultaneously investigate the responses of the soil organic carbon (SOC) and soil inorganic carbon (SIC) stocks of alpine meadows to the disturbance caused by this small burrowing herbivore and its disturbance intensity at the plot scale across five sites on the Qinghai‐Tibetan Plateau. The percentage of bare soil area in a disturbed plot was used as a proxy for the disturbance intensity of plateau pikas. Our study found that the disturbance by plateau pikas reduced the SIC stock and increased the SOC stock, whereas it had no effect on the soil total carbon (STC) stock. Our study also found that the SOC and STC stocks were higher at intermediate disturbance intensities of plateau pikas, whereas the SIC stock showed a decreasing trend as the disturbance intensity of plateau pikas increased. Our findings suggest that intermediate disturbance intensities of a small burrowing herbivore (plateau pika) improve soil quality by increasing the SOC stock and benefit soil carbon sequestration by increasing the STC stock. Highlights: Explored the SIC and SOC stocks simultaneously in relation to the disturbance by a small burrowing herbivore.Soil carbon stocks were evaluated at plot scale across five sites.SIC and SOC stocks responded differently to the disturbance by plateau pika and its disturbance intensity.The intermediate disturbance intensities were good for the soil quality and soil carbon sequestration. [ABSTRACT FROM AUTHOR]