Dry-farming system is commonly used in the Algerian semi-arid High Plateaus. It is based on cereal/sheep production in a cereal-fallow rotation. This cropping system degrades the structure f thetilled horizon and reduces its organic matter content (Kribaa et al, 2001). Soil structure degradation is reported as a major constraint regarding water infiltration, redistribution and storage in the soil profile (Canolly, 1998). It often results from the disturbance induced by tillage-tools. Under the crop growth conditions of the Sétif High Plateaus, as far as soil humidity is concerned, it appeared clearly that fallow till gave best results than no-till. This may be explained by the surface crusting that seals soil and by the absence of pores connectivity in the no-tilled fallow which penalized crop at the beginning of the season through a low stand. Hence under the no-till option,chiselling i.e. no soil reversing seems required. Direct seeding on cover crop may also be explored in theses conditions.

Within the framework of adopting direct seeding mulch-based cropping systems (DMC) in cotton farming systems in North Cameroon, we compared the macrofauna patterns from four soil management techniques: (1) non tilled soil covered with the graminousceaeBrachiaria ruzisiensis , (2) non tilled soil covered with leguminous plants,Crotalaria retusa orMucuna pruriens , (3) non tilled soil and (4) conventional tilled soil. In both study sites, micro-plots had been subjected to the same farming systems for the past 3 years. Sampling of organisms was carried out from soil cubes (30 cm) examination, including soil and litter. The findings revealed that diversity, equitability as well as abundance of extracted macrofauna were found to be generally more important in mulch-based cropping plots: soil and surface litter transformers (earthworms, diplura, thysanura, etc.), but also predators (spiders, centipedes, carabids, etc.) and phytophagous arthropods such as millipedes. These preliminary results underline a significant impact of soil management techniques on macrofauna pattern and trophic communities, with key organisms serving as potential indicators of the biological activity of the soil.

The present study, conducted during the rainy season 2002, analyses agro-economic components of conventional transplanting and direct seeded rice on lowland ecosystem (lower and upper terrace). Direct seeded rice varieties, on weeds and rice residues, have been tested on uppers terraces where no conventional rice system could be performed.

Fiche montrant les principes du Semis Direct sur couverture végétale (SCV) et leurs applications en régions tropicales et tempérées et différents itinéraires techniques avec diverses mécanisations.

Influence de la fréquence et de l'intensité de la combustion selon le type de sols de tanety

Dossiê sobre Sistema de cultivo e Dinâmica da Matéria Orgânica -Parte 2 2001. Sistemas de plantio direto, evolução da M.O. e sequestro do C, evoluções das produtividades de arroz de sequeiro, soja e algodão, e das margens dos sistemas comparados (convencionais e Plantio Direto). Experienças do Centro Oeste brasileiro, do Gabão e de Madagascar. Utilzação das reservas hidricas no perfil cultural, e conclusões. Systèmes de culture et Dynamique de la matière organique - Partie 2 systèmes de Semis Direct, évolution de la M.O. et séquestration du C, évolutions das productivités de riz pluvial, soja et coton, et des marges des systèmes comparées (conventionnels et Semis Direct SCV), utilisation des réserves d'eau dans le profil cultural, et conclusions.

Méthodologie, systèmes de Semis Direct, évolution de la M.O. et séquestration du C, évolutions des productivités de riz pluvial, soja e coton, et des marges des systèmes comparés (conventionnels et Semis Direct). Expériences du Centre Ouest brésilien, de Madagascar. Fonctionnement du Semis Direct et Photographies

Systèmes de culture et Dynamique de la matière organique - Partie 1 Méthodologie, systèmes de Semis Direct, évolution de la M.O. et séquestration du C, évolutions das productivités de riz pluvial, soja et coton, et des marges des systèmes comparées (conventionnels et Semis Direct SCV).

Sistema de cultivo e Dinâmica da Matéria Orgânica 2001. Metodologia,sistemas de plantio direto, evolução da M.O. e sequestro do C, evoluções das produtividades de arroz de sequeiro, soja e algodão, e das margens dos sistemas comparados (convencionais e Plantio Direto).