Mineralogical and physico-chemical properties of Ferralic Arenosols derived from unconsolidated Plio-Pleistocenic deposits in the coastal plains of Congo

Autor: J.C. Mazoumbou, Marie-Pierre Turpault, Jean-Paul Laclau, A. Thongo M'Bou, Jean-Pierre Bouillet, Jacques Ranger, Jean de Dieu Nzila, Louis Mareschal
Přispěvatelé: Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Centre de Recherche sur la Durabilité et la Productivité des Plantations Industrielles (CRDPI), Université Joseph Ki-Zerbo [Ouagadougou] (UJZK), Ecole Normale Supérieure de Brazzaville, Partenaires INRAE, Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF), Institut National de la Recherche Agronomique (INRA), CRDPI, Republic of Congo, CIRAD, EFC s.a., GIP Ecofor
Jazyk: angličtina
Rok vydání: 2011
Předmět:
IRON-OXIDES
010504 meteorology & atmospheric sciences
[SDV]Life Sciences [q-bio]
Geochemistry
EUCALYPTUS PLANTATIONS
Kaclinite
01 natural sciences
Pédogénèse
Cation-exchange capacity
BIOGEOCHEMICAL CYCLES
2. Zero hunger
Capacité d'échange cationique
Eucalyptus
Cat on exchange capacity
04 agricultural and veterinary sciences
Sol tropical
ORGANIC-MATTER
ACFOREST SOILS
[SDE]Environmental Sciences
SPATIAL-DISTRIBUTION
Clay minerals
Geology
Arénosol
CATION-EXCHANGE CAPACITY
P33 - Chimie et physique du sol
CLONAL STAND
Weathering
Plantations
Soil Science
Mineralogy
Vermiculite
CHEMICAL-COMPOSITION
Kaolinite
Propriété physicochimique du sol
ADJACENT SAVANNA ECOSYSTEM
0105 earth and related environmental sciences
Pedogenesis
15. Life on land
K10 - Production forestière
Clastic rock
Soil water
040103 agronomy & agriculture
0401 agriculture
forestry
and fisheries
Sedimentary rock
Minéralogie
Tropical soil
Zdroj: Geoderma
Geoderma, Elsevier, 2011, 162 (1-2), pp.159-170. ⟨10.1016/j.geoderma.2011.01.017⟩
ISSN: 0016-7061
1872-6259
DOI: 10.1016/j.geoderma.2011.01.017⟩
Popis: International audience; The main characteristics of soils under commercial Eucalyptus plantations on the Atlantic coast of the Congo were studied down to a depth of 5 m. The objectives were to invest gate the mineralogical assemblage and distinguish between current versus old pedogenetic processes, and to find evidence of relations between minerals and cation retention in highly weathered sandy soil. These soils, developed from Plio-Pleistocene sandy deposits, were characterized by mineralogical uniformity over depth, with quartz contents ranging from 850 to 930 g kg(-1), a clay fraction dominated by kaolinite and a cation exchange capacity (CEC) < 0.5 cmol(c) kg(-1) whatever the soil layer. Whilst dioctahedral vermiculite amounted to only 3% of the clay fraction, it played a key role in soil cation retention contributing to 49% of the mineral CEC. Vermiculitisation of muscovite was a current process showed by the changes in muscovite/vermiculite ratios with soil depth. The simple mineralogical assemblage of this soil made it possible to estimate CEC values for kaolinite ranging from 6.2 to 6.9 cmol(c) kg(-1) for the 0-2 mu m particle size. Their morphologies and saturation index of soil solutions showed that kaolinite had different possible origins: i) current precipitation from soil solution, ii) pseudomorphic transformation of pre-existing 2:1 phyllosilicates and iii) old particles present in the original deposit. Measured fine earth CEC below estimations summing together the contributions of all the mineralogical fractions showed that particle aggregation greatly influenced the cation retention capacity, even in these poorly structured soils. Pedogenetic differentiations were weak in these soils because the elapsed time since deposition was too short to differentiate 'mineralogical horizons' from weathered materials. Our study showed that beyond the properties that minerals confer to soil, partially controlling the bioavailability of nutrients, their mineralogical and chemical characteristics infer current and former pedogenetic processes in this highly weathered tropical soil. (C) 2011 Elsevier B.V. All rights reserved.
Databáze: OpenAIRE
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