@article{fdi:010060519,
  title = {{C}itrate adsorption can decrease soluble phosphate concentration in soils : results of theoretical modeling},
  author = {{D}uputel, {M}. and {D}evau, {N}. and {B}rossard, {M}ichel and {J}aillard, {B}. and {J}ones, {D}. {L}. and {H}insinger, {P}. and {G}erard, {F}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A} major problem for 21st century agriculture is the prospect of {P} scarcity. {A}dsorption of {PO}4 on the soil's solid phase is the primary mechanism regulating {P} availability. {R}elease of citrate by roots is generally thought to increase the availability of {P}, which in turn improves {P} acquisition by plants. {H}owever, the interaction between citrate and {PO}4 remains poorly understood in soils and conflicting results are found in the literature. {H}ere modeling is used to investigate the effects of citrate adsorption on {P} availability in a chromic cambisol, a luvisol and two ferralsols over a range of soil p{H} values. {T}he effect of different levels of exchangeable {C}a, soil organic {C} ({SOC}), dissolved organic {C} ({DOC}) and {PO}4 fertilization were also tested in order to cover a wider range of environmental conditions. {R}esults showed that the competition of citrate for {PO}4 binding sites was not the only mechanism regulating {P} availability. {C}itrate adsorption can also increase {PO}4 adsorption through electrostatic interactions with adsorbed {C}a2+ ions and actively reduce {P} availability. {M}ore precisely, it was found that the addition of 10 lmol citrate kg (1) soil decreased {P} availability in both chromic cambisol and luvisol. {T}he same trend was predicted by the model with 100 mu mol of citrate kg (1) soil in the chromic cambisol, whereas available {P} was found to increase in the luvisol. {I}n contrast, the addition of citrate at these two concentrations always increased {P} availability in the two ferralsols. {I}ncreasing exchangeable {C}a further decreased {P} availability in the chromic cambisol and luvisol, while it further increased available {P} in ferralsols. {A}dditional sensitivity tests showed that {DOC} concentration had little influence on these results. {I}n contrast, increasing {SOC} concentration massively counteracted the deleterious influence of citrate in chromic cambisol, while the effect was amplified in luvisol. {I}n ferralsols, it was mainly observed that the increase of {SOC} further promoted {P} availability. {T}o conclude, it was found that citrate can either increase or decrease {P} availability in soil, depending mainly on the occurrence of 2:1 clay minerals and on the concentrations of citrate, adsorbed {C}a, and soil organic {C}. {S}pecial attention should, therefore, be given to possible adverse effects of rhizosphere management for improved {P} nutrition.},
  keywords = {},
  booktitle = {},
  journal = {{A}pplied {G}eochemistry},
  volume = {35},
  numero = {},
  pages = {120--131},
  ISSN = {0883-2927},
  year = {2013},
  DOI = {10.1016/j.apgeochem.2013.03.018},
  URL = {https://www.documentation.ird.fr/hor/fdi:010060519},
}