Global phosphorus addition database (GPAD) for soil carbon response

In this database, we collected 2882 observations from 213 field phosphorus-addition experiments worldwide. This database was initially created to explore the effects of phosphorus addition on soil carbon storage and the associated mechanisms, and covers multiple variables of ecosystem carbon cycling. Specifically, the variables include soil organic carbon and its fractions (particulate organic carbon and mineral-associated organic carbon), dissolved organic carbon, plant above- and belowground biomass, microbial biomass, litterfall production, soil organic matter decomposition, soil properties (e.g., pH, total and available nitrogen). This dataset also includes site and treatment information of these phosphorus-addition experiments, such as, location, climatic factors (temperature and precipitation), plant N fixation status (symbiotic N fixer vs. non-N fixer), mycorrhizal types (arbuscular mycorrhizal and ectomycorrhizal), soil types, sampling depth of soil, and rate, form and duration of P addition.