Fertilizer material Page no 5 Organic sources Proper maintenance of soil organic matter is an important part of nutrient management, as increasingly supported by the scientific community. Organic matter enhances both chemical and biological soil properties, as well as supplying sources as macro- and micronutrients. The most stable form of organic matter—humus—plays an all-important role in improving soil structure, nutrient retention, and water storage. Additionally, it has been shown that additions of animal and green manures, as well as compost, enriched microbial diversity and populations. NITROGEN Animal manure The amount of nitrogen that manure provides and its subsequent availability to plants is influenced by a several factors: Nutrient analysis of the animal feed Storage and handling procedures of the manure Amount and type of materials added to the manure Timing and method of application Properties of the soil Choice of crop Nitrogen Analysis Manures can contain between 0.5 and 6% total nitrogen, though typical values range from 0.5 to 1.5%. Of the total nitrogen, approximately only 25% to 50% is in the form of ammonium and directly available to plants./li> The remaining 50-75% is organic nitrogen and must be mineralized before it is utilized by plants. Thus, the same conditions for optimal mineralization of organic matter are the same for the optimal mineralization of organic nitrogen in manure. Organic Nitrogen Organic nitrogen is further divided into two categories: unstable organic nitrogen stable organic nitrogen Unstable organic nitrogen urea or uric acid are the primary forms of unstable organic nitrogen mineralization into ammonium occurs rapidly highly vulnerable to volatilization and denitrification losses it is recommended that manure be incorporated into the soil to prevent nitrogen losses to the atmosphere Stable organic nitrogen mineralizes at much slower rates than the unstable fraction the stable nitrogen that is less resistant to decomposition (approximately 30% to 60% of the total nitrogen) mineralizes during the first year of application the stable nitrogen that is more resistant to decomposition mineralizes during the following years with declining rates of mineralization each year that passes.
Posted on: Mon, 29 Dec 2014 17:34:18 +0000