The depth distribution of carbon inputs to soil has been unquantified globally, hindering our understanding of belowground carbon dynamics. We synthesize global observational data to infer the allocation of carbon inputs to soil depths down to 2 m, and map depth-specific carbon inputs globally at 1 km resolution. Global average carbon input to the 0–20 cm soil layer is 1.1 Mg C ha–1 yr–1, accounting for >50% of total soil carbon inputs. Across the globe, the depth distribution of carbon inputs shows large variability, and there are relatively more carbon inputs to deeper layers in hotter and drier regions. Edaphic, climatic and topographic properties (in the order of importance) explain >80% of such variability in soil depths; and the direction and magnitude of the influence of individual properties are soil depth- and biome-dependent. Our results provide global benchmarks for prediction of whole-soil carbon profiles across global biomes.

Accurate estimation of N2O emission is one of the primary objectives to project the warming potential. However, the global patterns and main controlling factors of soil N2O emission remain elusive. We compiled a dataset with 6016 field observations from 219 articles and found that the averaged soil N2O emission rate was 1111.8 ± 26.59 µg N m-2 day-1. Soil N2O emission rates were significantly influenced by climatic factors (i.e. mean annual temperature), soil physical and chemical properties (e.g. pH, nitrate, ammonium, and total nitrogen), and microbial traits (microbial biomass nitrogen) at a global scale. The combined direct effects of soil nitrate, ammonium, and total nitrogen (combined standard coefficient = 0.45) accounted for the most variance of global soil N2O emissions (total standard coefficient = 0.84). This study highlights the critical roles of soil nitrogen substrates on N2O emission, which will be helpful to optimize the process-models on soil N2O emissions.

Predicting how warming-induced shifts in plant species-specific phenology affect species dominance remains challenging. Here, we investigated the effects of experimental warming on plant species-specific phenology and dominance as well as their relations in an alpine meadow on the Tibetan Plateau. Warming significantly advanced phenological firsts (leaf out and first flower dates) for most species, while having variable effects on phenological lasts (leaf senescence and last flower) and full phenological periods (growing season and flower duration). Experimental warming reduced community evenness and differentially impacted the species-specific dominance. Specifically, warming-induced shifts in phenological lasts and full phenological periods, rather than the single phenological firsts, are associated with changes in species dominance. Species with lengthened full phenological periods under warming increased their dominance. Our results advance our understanding of how altered species-specific phenophases can be related to changes in community structure in response to climate change.