@article{fdi:010048242,
  title = {{T}owards an understanding of coupled physical and biological processes in the cultivated {S}ahel-2. {V}egetation and carbon dynamics},
  author = {{B}oulain, {N}icolas and {C}appelaere, {B}ernard and {R}amier, {D}avid and {I}ssoufou, {H}. {B}. {A}. and {H}alilou, {O}. and {S}eghieri, {J}osiane and {G}uillemin, {F}. and {O}i, {M}onique and {G}ignoux, {J}. and {T}imouk, {F}ranck},
  editor = {},
  language = {{ENG}},
  abstract = {{T}his paper analyses the dynamics of vegetation and carbon during the {W}est {A}frican monsoon season, for millet crop and fallow vegetation covers in the cultivated area of the {S}ahel. {C}omparing these two dominant land cover types informs on the impact of cultivation on productivity and carbon fluxes. {B}iomass, leaf area index ({LAI}) and carbon fluxes were monitored over a 2-year period for these two vegetation systems in the {W}ankama catchment of the {AMMA} ({A}frican monsoon multidisciplinary analyses) experimental super-site in {W}est {N}iger. {C}arbon fluxes and water use efficiency observed at the field scale are confronted with ecophysiological measurements (photosynthetic response to light, and relation of water use efficiency to air humidity) made at the leaf scale for the dominant plant species in the two vegetation systems. {T}he two rainy seasons monitored were dissimilar with respect to rain patterns, reflecting some of the interannual variability. {D}istinct responses in vegetation development and in carbon dynamics were observed between the two vegetation systems. {V}egetation development in the fallow was found to depend more on rainfall distribution along the season than on its starting date. {A} quite opposite behaviour was observed for the crop vegetation: the date of first rain appears as a principal factor of millet growth. {C}arbon flux exchanges were well correlated to vegetation development. {H}igh responses of photosynthesis to light were observed for the dominant herbaceous and shrub species of the fallow at the leaf and field scales. {M}illet showed high response at the leaf scale, but a much lesser response at the field scale. {T}his pattern, also observed for water use efficiency, is to be related to the low density of the millet cover. {A} simple {LAI}-based model for scaling up the photosynthetic response from leaf to field scale was found quite successful for the fallow, but was less conclusive for the crop, due to spatial variability of {LAI}. {T}ime/space variations in leaf distribution for the dominant species are key to scale transition of carbon dynamics. {R}esults obtained for the two vegetation covers are important in light of the major land use/cover change experienced in the {S}ahel region due to extensive savanna clearing for food production.},
  keywords = {{A}ssimilation ; {R}espiration ; {F}allow savanna ; {M}illet ; {W}est {A}frica ; {C}arbon ; dioxide},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {375},
  numero = {1-2},
  pages = {190--203},
  ISSN = {0022-1694},
  year = {2009},
  DOI = {10.1016/j.jhydrol.2008.11.045},
  URL = {https://www.documentation.ird.fr/hor/fdi:010048242},
}