Optimizing Fertilizer Application in Relation to Soil Nutrients Analysis Sustaining Environment; Case Study corn Farms of Kuzaran, Kermanshah Province, Iran

Corn (maize) is cultivated in several parts of irrigation lands of Iran and over application of chemical fertilizers causing environmental and human health impacts. However, soil nutrients available analysis can be improved with optimal chemical fertilizer consumption in these farms. The objective of this research was to evaluate soil nutrients content and appropriate fertilizers application in the corn farms which was conducted in Kuzaran, west Kermanshah, Iran. Soil sampling carried out from 0-30 soil depth and subjected to soil organic carbon (SOC) content as well as availability of N, P, K, Mn, Fe and Zn analysis. The results showed that the mean SOC was low (1.23%) and significantly (p<0.05) correlated to all measured soil nutrients. The respective average level of N, P, K, Mn, Fe and Zn was 0.121, 17.00, 381, 9.71, 12.41 and0.86 mg-1 kg. The recommended consumption rates included triple super phosphate, potassium sulfate and iron, hence; these rates were not correlated with P, K and F available in the soil. Furthermore, recommended potassium sulfate input was 134 kg/ha, while soil K available was sufficient for corn crop. In contrasts, the recommended levels of Urea (418 kg/ha), manganese sulfate (32.4 kg/ha) and Zinc sulfate (54.3 kg/ha) were significantly correlated with soil N, Mn and Zn content. Thus, recommended chemical fertilizers application was not sufficiently accurate and did not follow by soil nutrients content. For sustaining environment and human health, the consumption of chemical fertilizer particularly in corn farms should be recommended based on soil nutrient analysis and crop needs.