Ecological intensification of agricultural production systems through waste recycling
Résumé
Organic waste (OW) generated by human activity is continuously increasing worldwide. Agriculture generates large amounts of OW derived mostly from livestock farming and agroindustries. Furthermore, OW flows are increasing as a result of urban development- wastewater, sludge and municipal waste may be treated to different degrees. These wastes are often applied on cultivated lands on the outskirts of cities. OW are sources of organic matter that may increase soil fertility and reduce the need for chemical fertilizers, thus enhancing sustainable agricultural production. They may also carry contaminants, and inappropriate application may lead to an accumulation of mineral, organic or metallic contamination, thus degrading soil quality and possibly increasing the risk of pollutant transfer to the harvested crops. The multiplication of product types and the diversity of situations in which they are produced and used are factors that should be considered to enhance OW management in agriculture. The ISARD project aims to develop a global approach for integrating knowledge concerning OW recycling in agriculture. Innovation in this project is related to the territorial approach with organic matter stemming from either agriculture or households, and mainly in suburban areas. The project is being implemented at four locations, with the following specific recycling issues: o Metropolitan Dakar (Senegal): possible ways of using mixed composts o Mahajanga region (Madagascar): making and using municipal waste compost o Versailles area (France): recycling stable manure and wastewater treatment sludge on cultivated plots o Réunion Island (France, Indian Ocean): organizing and assessing the recycling of various wastes at a territory level The expected result to be delivered when the project is completed is a generic methodology that will make it possible for agronomists working with rural stakeholders to create highly efficient cropping and farming systems based on the use of a wide range of organic wastes.