Urea or Urea-Formaldehyde Loading With Some Micronutrients Nitrogen and for Iron Availability in Different Soil Types

This work was conducted to evaluate the effect of loading some micronutrients on urea or urea formaldehyde for delaying the nitrogen and iron release rate from urea and urea-formaldehyde compared in in different soil types (clay located at 30ᵒ 01` N, 31ᵒ 13` E, sandy loam located between 30° 35' 30" N, 32° 14' 50" E and calcareous located at 30°40′N 30°04′E). Reducing the release rate of urea can increase its availability and minimize negative effects on the environment. A novel fertilizer material that was formed by blending formaldehyde with urea, delayed fertilizer N release in controlled climatic conditions in a greenhouse, through strong retention facilitated by the extensive surface area, porous structure and chemical functional groups in the formaldehyde. Moreover, loading some micronutrients was aimed to increase the nitrogen fertilizers availability. Data indicated that the nitrogen and iron release rate in urea-formaldehyde sole was slower than urea sole regardless to soil type, while after loading Fe, Mn or Zn on urea and urea-formaldehyde data could be summarizes as the following, the applied nitrogen sources could be represented in the descending order as: Fe-urea formaldehyde> Zn- urea formaldehyde>Mn- urea formaldehyde> urea formaldehyde> Fe- urea> Zn- urea>Mn- urea> urea, respectively. Also, for soil type data indicated that the nitrogen release rate in clay soil was higher than calcareous and sandy soils for all treatment under study.