@article{fdi:010063320,
  title = {{R}egulation of carbon and nitrogen exchange rates in biological soil crusts by intrinsic and land use factors in the {S}ahel area},
  author = {{B}ertrand, {I}. and {E}hrarhdt, {F}. and {A}lavoine, {G}. and {J}oulian, {C}. and {M}alam {I}ssa, {O}umarou and {V}alentin, {C}hristian},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he occurrence and diversity of biological soil crusts ({BSC}) a thin soil surface layer composed of phototrophic and heterotrophic microorganisms intimately associated with soil particles, are known as strong indicators of ecosystem health and sensitivity to soil surface disturbances and are key factors in the biochemical cycling of carbon and nitrogen in drylands. {H}owever, the impact of land use on {C} and {N} budgets related to {BSC} dynamics is poorly understood and hinders the prediction of changes in soil fertility in response to future land use scenarios. {I}n this study, we examined the {C} and {N} exchange rates of {BSC} sampled along a north-south pluviometric gradient of the {S}ub-{S}ahel, which provides evidence of increasing human land pressure, leading to a gradient in fallow duration and trampling intensity. {W}e demonstrate that the net and gross photosynthesis by {BSC} significantly increases with fallow duration and a reduction of trampling intensity, thus affecting {BSC} fine particles and relative water content. {C}onversely, no effect of land use was found on {N} fixation or mineralisation rates, which are instead regulated by the {N} availability within the crust. {S}imple statistical models were derived from the relationships between {C} exchange rates and {BSC} intrinsic characteristics related to soil surface disturbances. {T}he proposed statistical models were tested for {C} gas exchange with independent data obtained from a new {BSC} dataset sampled in {B}urkina {F}aso and {N}iger. {A} simple equation using {BSC} fine particle content as a unique variable was found to explain between 60 and 70% of the gross photosynthesis. {O}ur findings will help in mapping photosynthesis and estimating the contribution of {BSC} to the carbon budget at a regional scale in the dryland area of the {S}ahel and to further testing of land use change scenarios.},
  keywords = {{SURFACE} {DU} {SOL} ; {CROUTE} ; {MICROORGANISME} ; {DIVERSITE} {SPECIFIQUE} ; {CYCLE} {BIOGEOCHIMIQUE} ; {CARBONE} ; {AZOTE} ; {MINERALISATION} ; {PHOTOSYNTHESE} ; {RESPIRATION} ; {UTILISATION} {DU} {SOL} ; {PRESSION} {FONCIERE} ; {JACHERE} ; {ENGRAIS} {ORGANIQUE} ; {TRAVAIL} {DU} {SOL} ; {BURKINA} {FASO} ; {NIGER} ; {SAHEL}},
  booktitle = {},
  journal = {{S}oil {B}iology and {B}iochemistry},
  volume = {72},
  numero = {},
  pages = {133--144},
  ISSN = {0038-0717},
  year = {2014},
  DOI = {10.1016/j.soilbio.2014.01.024},
  URL = {https://www.documentation.ird.fr/hor/fdi:010063320},
}