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Anthropogenic inputs of nitrogen (N) and phosphorus (P) to terrestrial ecosystems alter soil nutrient cycling. However, the global‐scale responses of soil P fractions to N and P inputs and their underlying mechanisms remain elusive. We conducted a global meta‐analysis based on 818 observations of soil P fractions from 99 field N and P addition experiments in forest, grassland, and cropland ecosystems ranging from temperate to tropical zones. Our global meta‐analysis revealed distinct responses of soil P fractions to N and P enrichment. For studies using the Chang and Jackson inorganic (Pi) method, we found that high N addition promoted the transformation of immobile Pi fractions into Ferrum/Aluminum‐bound Pi and available Pi in surface soils through soil acidification. However, this acid‐induced transformation of Pi fractions by N addition was observed only in Calcium‐rich soils, while in acidic soils, further acidification led to increase P binding. In contrast, additions of P alone or combined with N significantly increased all soil Pi fractions. Regarding the Hedley P fractions, N addition generally decreased labile organic P by enhancing soil acid phosphatase activity. The responses of other P fractions were influenced by soil pH, fertilization rates, ecosystem type, and other factors. P addition increased most soil P fractions. Overall, both P fractionation methods consistently demonstrate that N inputs deplete soil P and accelerate P cycling, while P inputs increase most soil P fractions, alleviating P limitation. These findings are crucial for predicting the effects of future atmospheric N and P deposition on P cycling processes. Plain Language Summary: Human activities have increased the amount of nitrogen (N) and phosphorus (P) in the environment, which has led to changes in the soil nutrients cycle. This study examined the global‐scale responses of soil P fractions to N and P inputs using a data set from 99 field experiments worldwide. The findings revealed distinct responses of soil P fractions to N and P enrichment. High N input resulted in the transformation of immobile inorganic P (Pi) fractions into available Pi in surface soils. This transformation was observed in calcium‐rich soils due to soil acidification. In contrast, in acidic soils, the acidification led to increased Pi binding. Moreover, N input generally decreased labile organic P, potentially by enhancing soil enzyme activity. Addition of P alone or combined with N significantly increased soil P fractions. These findings have important implications for predicting the effects of future N and P deposition on P cycling processes in the terrestrial ecosystems and understanding the impacts of nutrient enrichment on soil carbon storage and eutrophication. Key Points: Nitrogen inputs can accelerate phosphorus (P) transformation in Calcium‐rich soils but promote P binding in acidic soilsSoil acidification reduces inorganic P bioavailability by increasing the P fixation of Ferrum and Alumiium oxidePhosphorus input increases soil labile, moderately labile, and occluded inorganic P, enhancing soil available P [ABSTRACT FROM AUTHOR]

Brazil, Mexico, Argentina and Chile are four large developing countries in Latin American that are going on their development stage comparable to China. Getting insight into the carbon emissions and the effectiveness of the carbon neutrality policies in these countries are expected to be beneficial for China s carbon neutrality aspirations. With the data of the national "fossil fuel carbon emissions and terrestrial carbon balance of the four countries from 1990 to 2016, this paper examined the individuality and commonality in the carbon emission and carbon sequestration features and the driving forces. Thereafter, based on a systematic and comprehensive review of policy planning related to long-term emission reduction goals in the four Latin American countries, the scenario analysis method was used to evaluate the carbon emission reduction effectiveness and carbon neutrality of each country from 2017 to 2050. It is found as follows. ➀ The economic growth and demographic expansion were the two most important factors that pushed the fossil fuel carbon emissions in all the four countries. The improvement in energy utilization intensity in Mexico, Argentina and Chile had the effect of mitigating carbon emissions. Deforestation deviated Brazil and Argentina from their carbon neutrality goals while Mexico and Chile s terrestrial ecosystems had sequestered amount of carbon from the atmosphere to offset their fossil fuel emissions, by which Chile is nearing its carbon neutrality. ➁ The scenario analysis suggested that the current policies might facilitate Brazil to commit its 2025 and 2030 goals and close to its 2050 carbon neutrality goal. The current policies may also support Argentina commit its 2030 goal and Chile commit its 2050 carbon neutrality goal. However, there are challenges to Argentina's 2050 goal and Mexico's all intermediate goals. In light of these results, China's carbon neutrality strategies should prioritize three aspects: optimizing the energy structure, promoting energy efficiency, and enhancing terrestrial carbon sink sequestration. [ABSTRACT FROM AUTHOR]

A major proportion of primary production is lost to insect herbivory. Leaf functional traits representing defense costs and palatability explain the intensity of herbivory at local scales. However, whether leaf traits explain herbivory at large scales needs clarification. By combining a leaf herbivory database and the TRY plant‐trait database, we compared 190 species from 65 families across 45 sites in nine countries. We hypothesized that defensive and/or nutrient‐poor leaves would compromise herbivory less globally. Both the absolute and percentage of maximum leaf‐area loss were higher in the tropical zone. Larger leaves lost more disproportionate areas to chewer herbivores whenever phylogenetic signals were considered. Thin leaves with low leaf mass per area (LMA) and short lifespan were compromised more by herbivory based on the leaf trait syndrome. Although thin leaves were rich in nitrogen, phosphorus, and calcium, only leaf nitrogen marginally explained the loss of leaf area. The contribution of leaf area dominated the herbivory intensity among all other morphological and chemical traits. Overall, the benefits of chewers on herbivory were based on leaf area, because the loss of leaf biomass and nitrogen increased proportionally with its loss. Leaf construction costs, but not nutrient content, determined the intensity of herbivory globally. However, the overall percentage of loss in leaf area was not high, demonstrating the importance of elucidating the relationship between leaf functional traits and induced defense in future studies. [ABSTRACT FROM AUTHOR]

Aboveground biomass (AGB) is the most dynamic carbon pool in forest ecosystems and is sensitive to biotic and abiotic factors. Previous studies on AGB have mostly focused on tropical and temperate forests, while studies on AGB and its determinants in subalpine coniferous forests are lacking and the mechanisms are not yet clear. Here, we systematically investigated all woody plants in 630 subplots (20 m × 20 m) in the Wanglang Plot (25.2 ha) to explore the spatial distribution of AGB and the effects of topography, soil, and stand structure on AGB. The results showed that AGB varied remarkably among different subplots with an average of 184.42 Mg/ha. AGB increased significantly with aspect, soil organic matter, maximum DBH, and important value of spruce–fir, while it decreased significantly with slope, total phosphorus, and stem density. Stand structure exerted greater influences than topography and soil factors, and especially maximum DBH determines the variation of AGB. Our results are of great significance to accurately estimate and predict the productivity of this forest type, and can provide insights into the diversity maintenance of subalpine coniferous forests as well as the conservation and management of forest ecosystems. [ABSTRACT FROM AUTHOR]

Forests provide a huge carbon pool, a substantial portion of which is stored in above‐ground biomass (AGB). Deciduous broadleaf forests in China are an essential component of global deciduous broadleaf forests, yet the impacts of climate and forest attributes on their AGB are not well understood.Using a comprehensive forest inventory database from 772 plots distributed across temperate and subtropical deciduous broadleaf forests in China (23.51°–42.53°N and 104.24°–128.27°E), we applied variance partitioning analysis, model selection analysis and structural equation models to explore how climate and forest attributes (species diversity, community‐level functional traits and stand structures) affect AGB in different climatic forests (semi‐arid forests, semi‐humid forests and humid forests).Community‐level functional traits and stand structures together explained a great portion of the variance in AGB. The effect of community‐level functional traits was greater than that of stand structures in semi‐arid forests and semi‐humid forests, but smaller in humid forests. Further analyses showed that community‐level maximum tree height, stem density and tree size inequality were important explanatory variables. Although climate and species diversity had minor effects, the direct positive effect of mean annual precipitation (MAP) was still important, especially in semi‐arid forests.Synthesis. Community‐level functional traits but not species diversity were key drivers of AGB, indicating that tree species diversity loss may not impair AGB substantially in deciduous broadleaf forests in China. Moreover, stand structures also had strong effects on AGB in both semi‐arid forests and humid forests, highlighting the importance of structural complexity. In addition, MAP had a direct positive effect on AGB in semi‐arid forests and semi‐humid forests, and a future increase in drought might potentially reduce carbon storage in these forests. [ABSTRACT FROM AUTHOR]