Impacts of soil properties on phosphorus adsorption and fractions in purple soils Impacts of soil properties on phosphorus adsorption and fractions in purple soils

最小化 最大化

Vol14 No.12: 2420-2431

Title】Impacts of soil properties on phosphorus adsorption and fractions in purple soils

Author】XIAO Yi1; TANG Jia-liang1*; WANG Ming-kuang2; ZHAI Long-bo1; ZHANG Xi-feng1

Addresses】1 Key Laboratory of Mountain Environment Evolution and Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; 2 Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Chinese Taipei

Corresponding author】jltang@imde.ac.cn

Citation】Xiao Y, Tang JL, Wang MK, et al. (2017) Impacts of soil properties on phosphorus adsorption and fractions in purple soils. Journal of Mountain Science 14(12). https://doi.org/10.1007/s11629-017-4545-2

DOI】https://doi.org/10.1007/s11629-017-4545-2

Abstract】Information on phosphorus (P) adsorption and its impacts on the redistribution of the P fraction in soil profiles are important for environmental management under intensive agricultural practices. To clarify the dominant factors influencing soil phosphorus adsorption in an Entisol (locally known as purple soil), P adsorption experiments were conducted in Sichuan Basin of southwestern China for cropland and woodland soils with acidic, neutral and calcareous origins throughout their profile. After various doses of P were added during incubation experiments, soil P fractions were also analyzed. The results showed that there were no significant differences in Fe-oxides and P adsorption along the vertical gradients. Agricultural practices and lower pH conditions reduced the P adsorption capacity of purple soils throughout the soil profiles. For acidic and neutral purple soil profiles, the P adsorption capability was mainly influenced by Fe-oxides and soil texture. Ca-bound P and Fe-Al-bound P represented the majority of the total inorganic P of calcareous soils. There was a saturation of adsorption capacity by sesquioxide and a high risk of dissoluble reactive P (NH4Cl-P) being released out of the soil profile in acidic and neutral purple soils after the greatest P addition, indicated by the higher proportions of NH4Cl-P (over 40%) and decreasing Fe-Al-P fraction. P fractions migrated with greater difficulty in calcareous purple soil profiles as Ca-P fraction peaked over 65% when adding a P dose at or greater than 80 g P kg-1, indicating the high potential of P adsorption. The X-Ray Diffraction analysis also verified the formation of brushite. Adaptive management practices should be designed to alleviate P losses for acidic and neutral purple soils.

Keywords】Agroecology; Soil parent material; Fe-oxides; Phosphorus adsorption; Incubation experiment; Phosphorus fraction