Nitrogen plant nutrient

For the year ended June 30, 1990, about 39% of the total primary nutrient used in the United States was apphed in mixtures, whereas the remaining 61% was apphed by direct apphcation. Breakdown by plant nutrient is shown in Table 11. High usage of anhydrous ammonia and nitrogen solutions (Fig. 

The tabulation of plant nutrient costs, by product, ia Table 16 shows the principal reasoa for the popularity of anhydrous ammonia as a fertilizer ia the United States. The fob price per ton of nitrogen in the form of ammonia is less than half that for any other nitrogen product. Also, ammonia s relatively high nitrogen content of 82.2% favors low transportation costs, in spite of the need for specialized handling equipment and procedures. 

Plant nutrient sulfur has been growing in importance worldwide as food production trends increase while overall incidental sulfur inputs diminish. Increasing crop production, reduced sulfur dioxide emissions, and shifts in fertilizer sources have led to a global increase of crop nutritional sulfur deficiencies. Despite the vital role of sulfur in crop nutrition, most of the growth in world fertilizer consumption has been in sulfiir-free nitrogen and phosphoms fertilizers (see Fertilizers). 

In hospitals, chemical analysis is widely used to assist in the diagnosis of illness and in monitoring the condition of patients. In farming, the nature and level of fertiliser application is based upon information obtained by analysis of the soil to determine its content of the essential plant nutrients, nitrogen, phosphorus and potassium, and of the trace elements which are necessary for healthy plant growth. 

Alternative crops Biofortification Diversification Decreases erosion Increases biodiversity Increases yield Increases soil nitrogen Recycles nutrients Pest control Plant disease control (2009) Deguine et al. (2009) Dordas (2009) Etchevers et al. (2009) Kalinova (2009) Knorzer et al. (2009) Malezieux et al. (2009) Palaniappan et al. (2009) Spiertz (2009) Zuo and Zhang (2009)... 

Plant nutrients are interesting not only in connection with the yields and the fertilisation, but also with regard to environmental effects of energy conversion processes. Thus, they are regulated in various standards. Nitrogen (N), phosphorous (P) and potassium (K), as well as sulphur (S) and chlorine (Cl) are the most important environmentally relevant macronutrient and micronutrient elements. 

Fig. 6.3 Conceptual drawing of the distribution of different groups of herbaceous plants in relation to major plant nutrients. Cycles represent the distribution of grasses, herbs, and legumes. Species with mycorrhiza are able to exploit sites low in both nitrogen (N) and phosphorus (P). Highly productive species, such as ruderal plants, need conditions abundant in N and P. 

Increased interest has been shown with regard to the plant nutrient content of slurry and experiments both in Sweden and elsewhere have demonstrated that a better utilization of the manure s nitrogen effect is obtained if the slurry is incorporated than if spread conventionally. In a time study made when the distance between the field and the manure pit was ca 800 m total spreading capacity decreased by ca 10% when the method was changed from conventional spreading to spreading using an injector. 

Part of the silicon is most likely a soil contaminant on the surface of the bracts while most of the other major elements detected are known to be plant nutrients. Silicon and silicates have been detected in a number of other plant mater ials (37,38). The plant nutrients nitrogen, phosphorous and potassium have been reported as a function of the maturity of cotton plants (39). 

To add plant foods Clovers and related green manures absorb nitrogen, a major plant nutrient, from the air and store it in nodules on their roots. It becomes available to plants when the green manure is dug in and decomposes. Other green manures root down to extract minerals from deep in the soil, bringing them up for subsequent shallow-rooted plants. 

The evolution of a lake or pond into dry land depends on the presence of nutrients in the water. The term nutrients refers to elements and compounds that are necessary for the growth of plants. Nutrients are commonly divided into two categories major nutrients and minor nutrients, also known as micronutrients. Despite some differences in the way that various elements and compounds are classified, carbon, nitrogen, and phosphorus are always regarded as major nutrients. Some authorities also list potassium, sulfur, calcium, magnesium, and/or iron as major nutrients. Micronutrients include aluminum, boron, chlorine, copper, manganese, molybdenum, silicon, and zinc. 

Mixed fertilizer A fertilizer that contains the plant nutrients nitrogen, phosphorus, and potassium. 

Nomenclature. Because the ammonium phosphate fertilizers contain two of the primary plant nutrients, il is pertinent at tilts point lo briefly continent on the manner in which these fertilizers are named. A series of three numbers, separated by dashes, is used lo indicate the primary nutrient content uf fertilizer mixtures. In order, from left lo right, the numbers show the percentage of nitrogen, phosphoric oxide, and potash ... 

UREA-AMMONIUM ORTHOPHOSPHATE. A fertilizer developed especially for food-deficient regions, particularly rice-dependent areas. Several grades contain all three primary plant nutrients (nitrogen, phosphorus, and potassium). Contains up to 60% nitrogen, phosphoric anhydride and potassium oxide. 

A.T. Wilson, Surface of the ocean as a source of air-borne nitrogenous material and other plant nutrients, Nature 184 (1959) 99-101. 

A commercial fertilizer is a material that contains at least one of the plant nutrients in chemical form that, when applied to the soil, is soluble in the soil solution phase and assimilable or available by plant roots. Most often, this implies chemical forms that are water soluble. However, in the case of phosphorus, solubility in special reagent solutions (citric acid, neutral ammonium citrate, or alkaline ammonium citrate) often is used as a guide for availability to plants. In the case of nitrogen, slow solubility in water may be more desirable from an environmental and efficiency standpoint than easy solubility. 

Animal and human wastes have long been used as fertilizers, especially in Europe and Asia, particularly China. Even some American Indians are said to have planted a dead fish in each com hill to increase yields. Such materials contain small percentages of nitrogen and other plant nutrients that are assimilable by plants. Today, the use of raw sewage on crops persists in Asia and Europe, but volumewise is not of great significance. In the United States and most European countries, the use of raw... 

Ammonia in Multinutrient Fertilizers. All the ammonia-based fertilizers discussed thus far contain only one of the three major plant nutrients, namely nitrogen. Referring again to Fig. 24.8, one may see that ammonia is the source of fertilizer nitrogen also, either directly or via nitrogen solids or solutions, in multinutrient fertilizers. These are fertilizers that contain two or three of the major plant nutrients—nitrogen, phosphorus, and potassium. Ammonium phosphates, both mono- and di-,... 

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