Chauvel Armand, Walker I., Lucas Yves. (1996). Sedimentation and pedogenesis in a central Amazonian black water basin. Biogeochemistry, 33, p. 77-95. ISSN 0168-2563.
Titre du document
Sedimentation and pedogenesis in a central Amazonian black water basin
Année de publication
1996
Type de document
Article
Auteurs
Chauvel Armand, Walker I., Lucas Yves
Source
Biogeochemistry, 1996,
33, p. 77-95 ISSN 0168-2563
Sedimentation rates were estimated in a Central Amazonian Black-water inundation forest. Sediment deposition on the forest ground, remote from the river bed, during an annual flood period, is of the order of 1 to 10 tons per hectare, depending on water depth and duration of flooding. The sediments consisted of fine organic matter, kaolinite, quartz sands and biogenic particles of silica. Their genesis and deposition depend on the interplay between pedogenic, limnological and biological processes. Sediments derive primarily from the materials leached from the soils. Clay soils are the main source of dissolved silica, and the sandy soils are the main sources of organic compounds and mineral particles. The physical sedimentation of particles as quartz and grains only occurs in the upper reaches of the studied river. In the flood plain, the sedimentation is due to the coagulation and deposition of combined mineral particles and humic substances, and to the biological precipitation of the silica leached from the soil by sponges. (Résumé d'auteur)
