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SummaryBiomass allocation can exert a great influence on plant resource acquisition and nutrient use. However, the role of biomass allocation strategies in shaping plant community composition under nutrient limitations remains poorly addressed.We hypothesized that species-specific allocation strategies can affect plant adaptation to nutrient limitations, resulting in species turnover and changes in community-level biomass allocations across nutrient gradients. In this study, we measured species abundance and the concentrations of nitrogen and phosphorus in leaves and soil nutrients in an arid-hot grassland. We quantified species-specific allocation parameters for stems vs leaves based on allometric scaling relationships. Species-specific stem vs leaf allocation parameters were weighted with species abundances to calculate the community-weighted means driven by species turnover.We found that the community-weighted means of biomass allocation parameters were significantly related to the soil nutrient gradient as well as to leaf stoichiometry, indicating that species-specific allocation strategies can affect plant adaptation to nutrient limitations in the studied grassland. Species that allocate less to stems than leaves tend to dominate nutrientlimited environments.The results support the hypothesis that species-specific allocations affect plant adaptation to nutrient limitations. The allocation trade-off between stems and leaves has the potential to greatly affect plant distribution across nutrient gradients.

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Soil loss tolerance (T value) serves as an ultimate criterion for determining if erosion control measures are necessary to preserve long‐term soil productivity; therefore, it must be determined scientifically and rationally. In this study, soil formation rates (SR) of the purple soils (Entisols in the U.S. Soil Taxonomy and Regosols in the FAO soil classification) in the hilly area of Sichuan, China, were determined in field plots (measured SR) for three treatments: (i) soil type (J2s, J3s, and J3p soils) and parent materials or bedrock, (ii) vegetation (wheat [Triticum aestivum L.]–maize [Zea mays L.], loquat tree [Eriobotrya japonica (Thunb.) Lindl.], and perennial ryegrass [Lolium perenne L.]), and (iii) soil depth (10, 20, 40, and 60 cm). The measured values were further used to test the applicability of the Barth equation (estimated SR) for the test soils. The measured SR varied among the treatments as a result of different characteristics of soil parent materials (PM) and different temperature and soil moisture at the interface between the soil and the parent materials. The trends (the order of increase or decrease) of measured and estimated soil formation rates were the same, however, for the soil type and vegetation treatments, but not for the soil depth treatments. The measured SR values were 800 Mg km−2 yr−1 for J3s purple soils and 1200 Mg km−2 yr−1 for J2s and J3p purple soils in the study region. The estimated SR values were closely related to runoff volumes but were substantially lower than the measured values. It was concluded that the Barth equation is not a reliable prediction model for estimating the soil formation rate for short‐term and plot‐scale observations. Therefore, T values should be determined by the measured SR values in the experimental region.