[Prev][Next][Index][Thread]
Mechanisms of aggregation of topsoils soils poor in expanding clays in Western African savannahs”
-
Subject: Mechanisms of aggregation of topsoils soils poor in expanding clays in Western African savannahs”
-
From: biotec@goliat.ugr.es
-
Date: 26 Nov 1996 12:29:59 GMT
-
Article: 16688 of alt.sustainable.agriculture
-
Newsgroups: alt.sustainable.agriculture
-
Organization: Centro Informatico Cientifico de Andalucia
A project entitled “Mechanisms of aggregation of topsoils soils
poor in expanding clays in Western African savannahs” lead by Dr.
Gérard Bourgeon, Centre de Cooperation International en Recherche
Agronomique pour le Dévelopment, Département de Cultures Annuelles,
(CIRAD-IRAT),France in partnership with other scientific
institutions in Burkina Faso, Mali Netherlands and France was
carried out under the European Union (D.G.XII) STD2 scientific
programme.
The aim of the project was:
- to study the factors and the state of aggregation of the soils in
two sectors of the sudanian-sahelian tropical zone;
- to reinforce the research capacity of institutions concerned with
the physics of sandy soils, a very difficult field;
- identification of agronomic techniques able to improve the
structure of the soils under cultivation.
In this context the project achieves scientific advance in :
- Doing the geological and pedological characterization of the
Saria region in Burkina Faso and of the Mobala region at Mali.
Tropical ferruginous soils, (ustalfs) developed on granite-gneisses
and sandstone’s, have been identified. These rocks are
representative of the lithological conditions of the
sudan-saheliens regions of West Africa.
- The characterization of the state and of factors aggregation of
sandy soils , which is very important to conservation and better
use of the soils, bearing in mind a sustained development-also an
objective.
- The quantification, on a landscape scale basis, of the role of
the pedological characteristics and of cultural practices in soil
structure.
-The application of a model which allows to breakdown porosity in
textural and structural terms, to these tropical soils. This type
of model only had been applied, before, in clay-silt soils of
temperate regions.
This model highlights the differences between the soils structural
state in respect to the different aspects of agricultural
environment, this is, an interaction environment-cropping system
exists.
The project highlights the necessity for experiments at landscape
unit level, to allow the generalization of results. Besides that it
is suggested the introduction of a control, representing the
traditional cropping systems of the region, when the aim of the
experiment is to improve these ones.
Finally, time is a key factor to achieve meaningful results, so the
experiments must be conduct in the long term.
Several cultural practices were recommended, among them the
addition of organic matter, and the benefits of its good
management, the introduction of fallow and gramineous plants for
forage, the abolishment of tillage procedures currently in use and
the application of new types of agricultural implements.
As in others projects the impact of this one depends on the way as
the results will be passed to the population. Which we think is
very important.
Within this project several publications have been issued.
For further information please contact:
Dr Gérard Bourgeon
Centre de Cooperation International en Recherche Agronomique pour
le Dévelopment, Département de Cultures Annuelles, (CIRAD-IRAT)
45 bis,Avenue de la Belle Gabrielle
94736 Nogent sur Marne, France
Phone +33 1 43 94 44 00
Fax +33 1 43 94 44 91
CONTRACT TS2- A -146