Application Effect of Domestic Sewage on Available Iron Concentration in Different Soil Depths

As more than 90 percent of water is used in agriculture, experts were made to turn to non-conventional waters, among which sewage is of significant importance due to having high amounts of plants required elements. The study was conducted with the objective of reviewing the impact of the application of raw and treated sewage on the trend of changes of iron in different soil depths. An experiment was performed three times to this end in the form of a CRD (Completely Randomized Design) with three treatments including tap water, treated sewage, and raw sewage. Soil sampling was done as composites at the soil depths of 0-30 and 30-60 cm. The available iron was determined in soil by DTPA method. The data experimented was analyzed at two probability levels of 1 and 5 percent by SPSS statistical software to determine the level of significance, and the Duncan test was used to compare the averages. The results from the statistical analysis showed that the use of raw and treated domestic sewage has stimulated an increasing trend in available iron concentration.