Disposal of Agro-Industrials Wastes as Soil Amendments

Abstract

We investigated the fertilizing potential of three agro-industrial wastes (Compost (C), Dehydrated Manures (DM) and Digestate (D)) on soil properties, on seeds germination and the plants growth. Results showed that the addition of wastes modified several soil properties as pH, Electrical Conductivity (EC), Water Retention Capacity (WRC) and Soil Organic Matter (SOM). Hence, SOM increase from 1.5% in unamended soil to 2, 2.3 and to 3.1% in soils amended with (D), with (DM) and with (C) respectively. A fast SOM biodegradation was illustrated in presence of compost where we noted a decrease of 20% of initial organic matter content. Besides, wastes improve strongly microbial and respirometric soil activities mainly in presence of DM and D. These same wastes stimulate seeds germination of two standard plants species (Tomato (Lycopersicon esculentum) and Alfalfa (Medicago sativa)). The growth levels of three cultivated plants species (Wheat (Triticum durum), Sorghum (Sorghum bicolor) and Alfalfa (Medicago sativa)) were enhanced in presence of wastes than those irrigated with water.