JWSS - Journal of Water and Soil Science

Cover crops, conservation tillage systems and organic fertilizers have played an important role in maintaining or enhancing soil quality. In order to assess the combined effects of these techniques on soil quality an experiment was conducted as split Plot experiment based on randomized complete block design with three replications at Shahid Bahonar University of Kerman in 2011-2012.
     The method of return of cover crops to soil included reduced tillage (disc) and no-till (herbicide glyphosate + cutting) as the main factor and manure application management included cover crops (wheat, canola and peas) without the use of urea, cover crops with a consumption of 25 t/ha of manure, Cover crop with 75 kg of urea and fallow treatments (without cover crop) as subplots. The results showed that the highest concentration of nutrients (except N and P concentrations in the plant), the nutrient yield and biomass of cover crops belonged to wheat treated with urea fertilizer. Soil properties such as bulk density, pH, organic matter and soil nutrient concentrations (nitrogen, phosphorus and potassium) were significantly affected by fertilizer management and the method of return of cover crops to soil (except pH) and soil organic matter content and nutrient concentration were affected by their interactions. In wheat cover crop treatments with urea with %27.53 reduction in bulk density, %20.88 increase in the porosity, organic matter 2.4 times and nitrogen 1.5 times compared to the fallow treatment was the best treatment that wasn’t significantly different from the wheat treated with manure in low- tillage system. Wheat treated by manure had the highest phosphorus that was 3.5 times of the phosphorus concentration in the fallow treatment. So, in order to develop sustainable agriculture, reducing the use of synthetic fertilizers and environmental protection, the wheat cover crop treatments with manure and low- tillage cropping systems would be appropriate in Kerman.