Evaluation of Sewage Sludge in Sudan as soil improver for crop production

Abstract

The aim of the present work was to study the effects of sewage sludge application on growth, and minerals
accumulation in selected crop tissues, as well as to investigate its effect on soil characteristics. Field experiments of
growing sorghum (sorghum bicolor), sunflower (Helianthus annuus), maize (Zea mays) crops under five loading of
sewage sludge, (0, 5, 10, 15 and 20 ton/hec), were carried out at the experimental farm of Soba sewage treatment
plant, south Khartoum during growing season of 2014 / 2015. The experiment was conducted using a completely
randomized design with 3 replicates. Plant height, leaves number, fresh weight and dry weight were measured after
30 and 60 days of growth. Also chemical, physical and biological properties of the investigated sludge and soil of the
experiment were evaluated. The concentration of lead, cadmium and chromium were determined in crop tissues. The
results indicated that sewage sludge contained significant concentration of total coliform and parasite eggs, also the
development of sorghum, maize and sunflower crops was significantly affected by the application of sewage sludge,
with significant change in soil properties. However, the effect of sewage sludge on soil characteristics was of no
consistent pattern.