Determination of Soil Aggregate Stability in Different Types and Amounts of Organic Matter in Khuzestan Plain, Iran

In soils under wheat cultivation, soil aggregates stability is increased and destructive effects of erosion decreased, due to organic matters (OM) application. This trail was conducted in Shavoor agriculture research station to determine of mean weight diameter (MWD) under different organic matter sources and amounts in Khuzestan province (at south west of Iran) via a split plot experiment based on randomized complete blocks design with three replications during three year. Main factor included seven kind of manure (Cattle and hen manures, sugarcane filtercack and baggass, wheat straw and green manure which compared with control, without any organic manures) and three amount of manure (2.5, 5 and 10 t.ha-1) belonged to sub factor. Result of analysis of variance showed effect of different source of OM and interaction effect of treatments (Different sources and amounts OM) on MWD was significant at 5% probability level but effect of year and sub factor on mention trait was not significant. Finally, in order to increase soil aggregates stability under climate and soil in the studied area, is advised before wheat planting at least 2.5 t.ha-1 of organic matter cellulose such as cereal residues and or sugarcane bagasse to be used. Compliance with this recommendation, after at least 4 to 5 years, the positive effect of OM increase in aggregate stability is evident.