Storage,Patterns and Environmental Controls of Soil Phosphorus in China
Based on the second national soil surrey data, the pools and spatial patterns of soil phosphorus density in China was investigated. The relationships between soil phosphorus density and environmental factors were also presented. The results indicate that the total national soil total and available phosphorus pools at actual depth are 5.1 Pg and 3.0 Tg, respectively. The average total phosphorus density and available density are 0.60 kg·m-2 and 3.4 g·m-2, respectively. Total soil phosphorus density, which negatively correlates with mean annual temperature and precipitation, showes increased tendency both from humid to semi-arid/arid zones and from tropical to frigid/temperate zones. Among different soil geochemical types, available phosphorus density of Siallitic soils significantly higher than those of Gypsum-bearing and Calcareous soils and Ferrallitic and Allitic soils. In conclusion, climate and soil geochemical types are important factors controlling soil phosphorus density in China.