In this study, Profs. Guo Licheng, Zhao Mingyu, Xiong Shangfa, and Yang Shiling from the Institute of Geology and Geophysics of the Chinese Academy of Sciences (CAS), together with their collaborators, compiled a geochemical dataset of global surface soils to investigate the relationship between climate and P weathering.
The dataset shows that temperature is the primary regulator of P mobility. It shows reduced P retention in soils in warmer climates (> 12°C) and with high silicate weathering intensities, characterized by the near-complete leaching of Na+, Ca2+, K+ from fresh regolith.
Further analysis indicates that lower soil pH in high weathering intensity environments promotes the removal of primary apatite and the dissolution of Al, Fe, Ca phosphates. In addition, in such environments, a higher kaolinite/illite ratio results in a decreased P adsorption capacity within clay minerals.
The researchers also calculated the relationship between modern global MAT and P weathering flux based on the observed relationship between MAT and P content, as well as the modern latitudinal distributions of temperature and land area. The model results show a rapid increase in P weathering flux within the global MAT range of 20°C to 23°C.