Fertilizers Supplement Natural Soils

Fertilizers that contain only one nutrient are called straight fertilizers. Potassium chloride for potassium is an example of a straight fertilizer. Those containing a mixture of the three primary nutrients are called complete, or mixed, fertilizers. The primary nutrients are absorbed by plant roots as simple inorganic ions nitrogen in the form of nitrates (NOp, phosphorus as phosphates (HgPO or HPO ), and potassium as the ion. Organic 

The cheapest source of nitrogen is the air, but it must be combined with relatively expensive hydrogen, obtained from petroleum, to form ammonia in the Haber process. 

The complex interactions among social, economic, and political necessities are well illustrated by the development of the industrial synthesis of ammonia. The need for an industrial process for nitrogen fixation was recognized as early as 1890. Scientists in England noted that the world s future food supply would be determined by the amount of nitrogen compounds 

Quick-release fertilizers Water soluble Slow-release fertilizers Combinations of plant nutrients that are slow to dissolve in water 

Ca Ca(OH)2 (calcium hydroxide, slaked lime), CaCOj (calcium 

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Land Farming. Land treatment is the most common method of oily solids disposal. The process is frequently referred to as land farming, as the oily waste is spread thinly, worked into the soil, fertilized, and watered. Manure or straw is added to reduce erosion lime addition reduces alkalinity. Commercially available strains of biodegrading bacteria may also be added to supplement the activity of naturally occurring strains. Because prevention of groundwater contamination is a serious concern, the same regulatory requirements applicable to landfill sites must be satisfied. 

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