@article{fdi:010061937,
  title = {{M}odelling microbial exchanges between forms of soil nitrogen in contrasting ecosystems},
  author = {{P}ansu, {M}arc and {M}achado, {D}. and {B}ottner, {P}. and {S}armiento, {L}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A}lthough nitrogen ({N}) is often combined with carbon ({C}) in organic molecules, {C} passes from the air to the soil through plant photosynthesis, whereas {N} passes from the soil to plants through a chain of microbial conversions. {H}owever, dynamic models do not fully consider the microorganisms at the centre of exchange processes between organic and mineral forms of {N}. {T}his study monitored the transfer of {C}-14 and {N}-15 between plant materials, microorganisms, humified compartments, and inorganic forms in six very different ecosystems along an altitudinal transect. {T}he microbial conversions of the {N}-15 forms appear to be strongly linked to the previously modelled {C} cycle, and the same equations and parameters can be used to model both {C} and {N} cycles. {T}he only difference is in the modelling of the flows between microbial and inorganic forms. {T}he processes of mineralization and immobilization of {N} appear to be regulated by a two-way microbial exchange depending on the {C} : {N} ratios of microorganisms and available substrates. {T}he {MOMOS} ({M}odelling of {O}rganic {M}atter of {S}oils) model has already been validated for the {C} cycle and also appears to be valid for the prediction of microbial transformations of {N} forms. {T}his study shows that the hypothesis of microbial homeostasis can give robust predictions at global scale. {H}owever, the microbial populations did not appear to always be independent of the external constraints. {A}t some altitudes their {C} : {N} ratio could be better modelled as decreasing during incubation and increasing with increasing {C} storage in cold conditions. {T}he ratio of potentially mineralizable-{N}-15/inorganic-{N}-15 and the {N}-15 stock in the plant debris and the microorganisms was modelled as increasing with altitude, whereas the 15{N} storage in stable humus was modelled as decreasing with altitude. {T}his predicts that there is a risk that mineralization of organic reserves in cold areas may increase global warming.},
  keywords = {{AZOTE} ; {CYCLE} {BIOGEOCHIMIQUE} ; {MODELISATION} ; {SOL} ; {MATIERE} {ORGANIQUE} ; {VENEZUELA}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {11},
  numero = {4},
  pages = {915--927},
  ISSN = {1726-4170},
  year = {2014},
  DOI = {10.5194/bg-11-915-2014},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061937},
}