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Rare and endangered species have narrow geographical distributions and are vulnerable to environmental changes. Studying the impact of future climate change on their distributions and identifying areas of high conservation priority are key to halting biodiversity loss. In this study, we combined a species distribution model with systematic conservation planning to simulate the suitable distributions of rare and endangered vascular plants and vertebrates in Inner Mongolia in the current and future (the 2050s), analyzed the vulnerability of species, and identified areas with high conservation priority. Currently, species richness (SR) of vascular plant was high in the Greater Khingan Mountains, and SR of vertebrates was high on the Hulunbuir Plateau, which are two species-rich areas. By 2050, 41.8% to 54.6% of vascular plants will have a reduced suitable distribution area, versus 46.8% to 51.1% for vertebrates. Vascular plant SR increased significantly in the Mu Us Desert, which became a new species-rich area. Vertebrate SR increased in western Inner Mongolia, but species-rich areas changed little. Species-rich areas are also potentially affected by future land use change, particularly in grassland, forest, and cropland areas with high SR. The current priority biodiversity conservation area covers 12.27 × 104 km2, of which 80.6% is located outside existing protected areas. By 2050, this percentage may increase to 83.4%. Our study revealed the potential pressure of existing protected areas in protecting biodiversity under future climate change, which helps decision-makers develop the most appropriate development strategies in advance to promote China's sustainable development. [ABSTRACT FROM AUTHOR]

• P limitation under grazing was driven by plant compensatory growth and soil P loss. • Available P concentration in the rhizosphere was increased under grazing. • Plant requirement for P stimulated its transition from organic into inorganic P. • LMWOAs and mycorrhizal fungi mobilized the rhizosphere P. • A medium grazing intensity is conducive to grassland's sustainable development. Soil erosion and phosphorus (P) removal due to livestock production have led to a grave depletion of P in grasslands. Accordingly, understanding how plants cope with such P limitation conditions and which P transition processes operate in the soil under different grazing intensities is imperative for better scientific management of grazed grasslands. Here, we conducted a field experiment that tested the impact of different grazing intensities (light, medium, and heavy) and a control (no grazing) on P-related dynamics in a typical temperate grassland site in Inner Mongolia, China. The increased N:P ratio in leaves of dominant plant species and higher annual primary production (APP) of vegetation that generally ensued under grazing indicated that plants' compensatory growth in response to grazing pressure was a factor contributing to P limitation. Plants' P requirement for growth stimulated P transition in the rhizosphere via the mobilization of low-molecular-weight organic acids (LMWOAs) and mycorrhizal fungi. Specifically, LMWOAs promoted the conversion of stable P into organic P, and mycorrhizal fungi converted that organic P into labile P in the rhizosphere. This P transition process is jointly affected by changes to key soil physiochemical properties and the altered P input from excrement caused by herbivores. Altogether, these results suggest that grazing increases the biological vitality of the soil and accelerates the transition of P in the rhizosphere; and a medium grazing intensity may be more suitable for agricultural production because it provides the highest APP and a more biologically dynamic soil environment. [ABSTRACT FROM AUTHOR]