@article{fdi:010061345,
  title = {{C}itrate adsorption can decrease soluble phosphate concentration in soil : experimental and modeling evidence},
  author = {{D}uputel, {M}. and {V}an {H}oye, {F}. and {T}oucet, {J}o{\¨e}le and {G}erard, {F}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he adsorption/desorption of phosphate ({PO}4) on soil minerals is a major process regulating soluble phosphate concentrations (i.e. phosphorus availability) and ultimately {PO}4 bio-availability. {R}elease of citrate by roots is widely recognized as an effective biological mechanism for increasing available phosphorus ({P}) in soil. {H}owever, interactions between citrate and {PO}4 are poorly understood and little investigated in soils. {U}sing surface complexation modeling we recently predicted that citrate adsorption can decrease available {P} in soils depending mainly on soil type and on citrate, exchangeable calcium, and soil organic carbon concentrations. {T}he most pronounced decrease was predicted in chromic cambisols. {T}he intention of the present study was to verify the accuracy of our predictions against experimental data measured in a real chromic cambisol, and to improve our understanding of {PO}4-controlling processes through surface complexation modeling. {T}he addition of a low to moderate citrate concentration (<50 mu {M}) effectively decreased available {P}. {I}n contrast, a concentration of 100 mu {M} produced an increase of available {P}. {T}he maximum decline of available {P} was observed at 20 mu {M} of citrate. {T}he agreement between simulated and measured values of {P} availability and total dissolved {C}a concentrations was excellent at a citrate concentration ranging from 0 to 50 mu {M}. {O}ur model substantially underestimated the increase of available {P} measured at 100 mu {M} of citrate. {T}his discrepancy showed the presence of another {PO}4-controlling process, which revealed to be the dissolution of {P}-containing minerals, most probably illite. {T}his study confirmed that the release of citrate in soils and its subsequent adsorption onto minerals can produce the decrease of {P} availability. {S}uch citrate-induced decreases of available {P} can be observed after addition of a relatively low concentration. {T}he threshold concentration was 20 mu {M} in the chromic cambisol investigated here. {T}his validation should have serious implications in the prospect of rhizosphere management for a better {PO}4 acquisition by plants through citrate release, as an adverse effect of citrate can be expected, depending on soil properties and citrate concentration. {T}his study also further demonstrated the ability of surface complexation models to reproduce and predict dissolved concentrations of various ions in soil solutions as a function of environmental conditions.},
  keywords = {},
  booktitle = {},
  journal = {{A}pplied {G}eochemistry},
  volume = {39},
  numero = {},
  pages = {85--92},
  ISSN = {0883-2927},
  year = {2013},
  DOI = {10.1016/j.apgeochem.2013.09.017},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061345},
}