%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture non répertoriées par l'AERES
%A Kabir, M.
%A Chotte, Jean-Luc
%A Rahman, M.
%A Bally, R.
%A Jocteur Monrozier, L.
%T Distribution of soil fractions and location of soil bacteria in a vertisol under cultivation and perennial grass
%D 1994
%L fdi:010013328
%G ENG
%J Plant and Soil
%@ 0032-079x
%K BIOLOGIE DU SOL ; BACTERIE ; NUMERATION ; VERTISOL ; BIOMASSE ; HERBACEE ; DENSITE DE POPULATION ; AGREGAT
%N 2
%P 243-255
%R 10.1007/BF00007974
%U https://www.documentation.ird.fr/hor/fdi:010013328
%> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_6/b_fdi_49-50/010013328.pdf
%V 163
%W Horizon (IRD)
%X Effects of soil management on soil characteristics were investigated on the rhizosphere (RPP) and the non-rhizosphere (NRPP) siol of a re-grass vertisol under #Digitaria decumbens$ and in the soil under continuous cultivation (CC). A low energy technique allowed to separate eight size and density fractions, including macro- and micro-aggregates while preserving soil bacteria. Organic C and N, microbial biomass C and the number of total bacteria (AODC) and of #Azospirillum brasilense$ and their distribution were determined in soil fractions isolated from the CC, NRPP and RPP soils. Soil macroaggregates (>2000 micrometers) were similarly predomminant in the NRPP and RPP soils when the dispersible clay size fraction (<2 micrometers) represented more than 25% of the CC soil mass. The main increase of C content in RPP originated from the macroaggregates (>2000 micrometers) and from the root fraction, not from the finer separates. The proportion of organic C as microbial biomass C revealed the low turnover of microbial C in the PP situations, especially in the clay size fraction of the NRPP soil. A common shift of AODC toward the finer separates from planted soils (CC and RPP) revealed the influence of living plants on the distribution of soil bacteria. The relative abundance of #A. brasilense$ showed the presence of the active roots of #Digitaria$ in the macroaggregates and their contact with the dispersible clay size fraction of the rhizosphere soil. (Résumé d'auteur)
%$ 074MICFLO01