The effect of municipal sewage sludge on properties physicochemical and microbial agricultural soil

Abstract

The organic matter content of sludge can improve the physical, chemical and biological properties of the soil ensuring better cultivation and good agricultural productivity. The objective of this study is to evaluate the effect of sewage sludge on the main physicochemical and biological properties of the soil. The sludge was spread in an agricultural field in Ain defla (Algeria) cultivated with a tomato crop (‘Panikra’) in four treatments: (T): soil without sewage sludge and without mineral fertilization, (B): soil with sewage sludge, (E): soil with mineral fertilization, (B + E): soil with sewage sludge and mineral fertilization. For this, several physical, chemical and microbiological properties were analyzed on the residual sludge used and the soils collected in the studied plots. The results show that the sludge used does not exhibit any toxicity and that the treatment with the sewage sludge with the fertilizer used on the agricultural soil forms a better compost for improving the physicochemical quality of the soil compared to the other treatments. The application of sewage sludge also can accelerate microbial activity by increasing the number of bacteria, fungi and azotobacter.