Abstract: Based on the second national soil survey 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 5.1Pg and 3.0Tg, respectively. The average total phosphorus density and available density are 0.60kg?m² and 3.4g?m², 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.

Key words: geochemical types, spatial patterns, soil phosphorus pool, climate

摘要： 基于第二次土壤普查资料，估算了中国土壤磷库，揭示了其空间分布规律，并探讨了土壤磷库与环境因子的关系。结果表明，中国土壤实际剖面深度的全磷和有效磷库分别为5.3Pg和3.0Tg，对应的磷密度为0.60kg/m²和3.4g/m²。土壤全磷密度自湿润区向干旱、半干旱地区和自热带地区向温带、寒温带地区呈增加趋势。土壤全磷密度随着年均降水量和年均温的增加而显著降低。在不同的土壤地球化学类型中，硅铝型的有效磷密度明显高于石膏及碳酸盐型和铁铝及富铝型。上述结果表明气候和土壤的地球化学类型是中国土壤磷素分布的重要因素。

关键词: 地球化学类型, 空间分布, 土壤磷库, 气候