@article{fdi:010009757,
  title = {{C}hanges of the forest-savanna boundary in {B}razilian {A}mazonia during the holocene revealed by stable isotope ratios of soil organic carbon},
  author = {{D}esjardins, {T}hierry and {C}arneiro {F}ilho, {A}. and {M}ariotti, {A}. and {C}hauvel, {A}rmand and {G}irardin, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he possibility of ecosystem boundary changes in northern {B}razilian {A}mazonia during the {H}olocene period was investigated using soil organic carbon isotope ratios. {D}etermination of past and present fluctuations of the forest-savanna boundary involved the measurement of natural 13{C} isotope abundance, expressed as delta 13{C}, in soil organic matter ({SOM}). {SOM} 13{C} analyses and radiocarbon dating of charcoal fragments were carried out on samples derived from soil profiles taken along transects perpendicular to the ecotonal boundary. {SOM} delta 13{C} values in the upper soil horizons appeared to be in equilibrium with the overlying vegetation types and did not point to a movement of the boundary during the last decades. {H}owever, delta 13{C} values obtained from deeper savanna and forest soil layers indicated that the vegetation type has changed in the past. {I}n current savanna soil profiles, we observed the presence of mid-{H}olocene charcoals derived from forest species : fire frequency at that time was probably greater, and more extensive savanna may have resulted. {I}sotope data and the presence of these charcoals thus suggest that the forest-savanna boundary has shifted significantly in the recent {H}olocene period, forest being more extensive during the early {H}olocene than today. {D}uring the middle {H}olocene, the forest could have strongly regressed, and fires appeared, with a maximum development of the savanna vegetation. {A}t the beginning of the late {H}olocene, the forest may have invaded a part of this savanna, and fires occurred again. ({R}{\'e}sum{\'e} d'auteur)},
  keywords = {{CONTACT} {FORET} {SAVANE} ; {HOLOCENE} ; {SOL} ; {CARBONE} {ORGANIQUE} ; {COMPOSITION} {CHIMIQUE} ; {ISOTOPE} ; {DATATION} ; {PALEOENVIRONNEMENT} ; {BRESIL} ; {AMAZONIE}},
  booktitle = {},
  journal = {{O}ecologia},
  volume = {108},
  numero = {},
  pages = {749--756},
  ISSN = {0029-8549},
  year = {1996},
  DOI = {10.1007/{BF}00329051},
  URL = {https://www.documentation.ird.fr/hor/fdi:010009757},
}