Influence of sewage sludge and organic composts on different soils under incubation periods: I. Zinc and copper releases Hala Kandil Plant Nutrition Department, National Research Centre, Dokki, Cairo, Egypt Abstract : This incubation experiment was conducted to evaluated the effect of different rates of sewage sludge (11, 22 and 44 ton fed -1 ) alone or in combination with three rates of banana Compost (BC) and/or cotton compost (CC) on release of extractable Zn and Cu from two different soils during incubation period up to 15 months. The obtained results can be summarized in the following: - Extractable Zn and Cu gradually increased with increasing the incubation period up to the end of 15 months. - The DTPA-extractable Zn and Cu under all the incubated organic manure treatments were remarkably higher than those obtained by control treatment. These results are true for Abou- Rawash sandy soil and El-Nobaria sandy calcareous soil as well as the incubation periods. - The incorporation of the SS 44 BC 22 or SS 44 CC 22 treatments in both soils at the different incubation periods significantly increased Zn and Cu under study when they compared with SS 22 BC 22 or SS 22 CC 22 treatments as well as SS 11 BC 22 or SS 11 CC 22 respectively. - The extractable heavy metals at the end of the experiment (after 15 month) in Abou-Rawash and El-Nobaria soils ranged from 8.07 - 13.78, and from 8.50 - 11.68 ppm for extractable Zn, from 1.70 - 4.51, and from 1.92 - 4.60 ppm for Cu, respectively. - It has been found that the incubation of SS and organic composts to agricultural land increased the release of DTPA- extractable of Zn and Cu in Abou-Rawash sandy soil than those in El-Nobaria sandy calcareous soil. Key words : Sewage sludge- Banana compost- cotton compost- Zinc- Copper- Heavy metals. Introduction Heavy metals released in to environment, among others by sewage sludge, pose a serious problem. While accumulating in living organisms they circulate in the trophic chain and moreover, their dangerous concentrations persist in ecosystems for a long time 1 . Currently remediation methods for heavy metals remove from soil and sludge are expensive and disruptive. Recently, efforts have been directed toward finding remediation strategies that are less expensive and less damaging to soil properties than current approaches. Organic materials such as crop residues, farmyard manure, town refuse, rice straw, cotton stalks, water hyacinth compost, etc.; are available in abundance and reach tremendous amounts day after day. In rural areas of Egypt most of the crop residues are used for energy production through direct burning. Obviously, this means the loss of a great proportion of the organic matter needed to be composed to keep soil productivity. International Journal of ChemTech Research CODEN (USA): IJCRGG, ISSN: 0974-4290, ISSN(Online):2455-9555 Vol.10 No.15, pp 108-114, 2017