fatooma a.m.rezig - Dese۱iification Reseru·ch Institute, National Center for Reseru·ch, Khruioum, Sudan
a.r mubarak - Dese۱iification and Dese۱i Cultivation Studies Institute, University of Khalioum,Shambat ۱۳۳۱۴, Khruioum N۰۱ih, Sudan
e.a elhadi - Dese۱iification Reseru·ch Institute, National Center for Reseru·ch, Khruioum, Sudan

Improving levels of organic matter in dese1i soils is necessruy for their cultivation. Two-year study (2008-2010) was conducted on a sandy clay loam soil at experimental reseru·ch frum of the Omdmman Islamic University, Sudan to dete1mine the effect of application of crop residues, sewage sludge and humentos on selected soil propeliies in wheat-gum· crop rotation system. Treatments were: recommended inorganic fe1iilizer (125 kg N ha-1 and 92kg P ha-1 ), recommended inorganic fertilizer with crop residues, crop residue, sewage sludge (1 0 t ha-1 ) , humentos soil conditioner (200 L ha- 1 ) and control..Results showed that soil physical prope1iies were not significantly changed except soil water holding capacity,. Application of crop residues with recommended fe1i ilizer and sewage sludge for three seasons significantly increased cation exchangeable capacity and organic eat·bon by 57.15 to 60.95 % and 61.0 to 65.2 %, respectively Moreover, combined application of crop residues with recommended inorganic feliilizer and sewage sludge had significantly decreased topsoil pH. It could be could be concluded that judicious combined application of organic wastes with inorganic feliilizers could be a usefhl practice in sustaining fe1iility of poor sandy soils.

crop residues, sewage sludge, wheat, guar, soil prope1iies