Residual Effects of Organic Fertilizers on Chemical Properties of Soil and lead Concentration

Organic fetiilizers contain high amount of micro nutrient and macro nutrient elements when these fetiilizers were added to the soil cause increasing in growth gain and ftmction in the plant. High concentration heavy metals lead to soil pollution and its transition to the food chain and risk human and animal health. The experiment was cmTied out in a completely randomized block design with seven treatments including : no fetiilizer as a control (C),sewage sludge (SW), cow manure (CM), municipal solid waste compost (MC), sewage sludge and cow manure(50% SW + 50% CM), sewage sludge and mlmicipal solid waste compost( 50% SW + 50% MC) and cow manure and municipal solid waste compos (50% CM + 50% MC) at three levels of 0, 2.5 and 5 kg/shrub and three replicates in calcareous sandy loam soil at the botanical gm·den of Mobm·ekeh steel company. After 2 years, soil sampleswere collected fmm 30 em depth and armmd the tree. Soil chemical propeliies alsototal concentration and DTP A- extractable of Pb were detennined. The results showed that all treatments significantly (P<0/01) increased organic matter (%OM), electrical conductivity(EC), and percent calcium cm·bonate (%CaC03), but there were no significant difference in pH and cation exchange capacity (CEC) in all treatments. Total concentration and DTPAextractable of Pb were significant in different phase of lead extraction. Maximum and minimum pmis were related to residual and exchange able Pb, which exchangeable pmi was significant in %1 level (P 0/01).The use of cow manure cause to significant increase in total concentration and DTPA - extractable of Pb.The highest salinity belongs to control group. Salinity of Organic fetiilizers didn't have significant difference. The highest pH value and percent organic matters belong to manure treatment .

Residual Effects of Organic Fertilizers on Chemical Properties of Soil and lead Concentration Keywords:

Sewage sludge , Cow manure , Urban compost , Heavy metal , Soil properties