Sulfur essential mineral nutrient

Minerals. Nuts are considered to be a good source of minerals essential for nutrition, supplying elements of copper, manganese, iron, and sulfur (see Mineral nutrients). The values for the mineral constituents of many nuts shown in Table 2 are averages of available analytical data. Values for the mineral content of the peanut kernel (28) and ash constituents in the macadamia kernel (29) and cashew (26) have also been reported. Chufa nuts have a high sihcon content. 

Phosphorus is an essential plant nutrient required for cellular DNA and other biomolecules. It is utilized by plants as H2PO4 and HPO ions. Phosphate minerals that can be used to manufacture phosphorus-containing fertilizers occur in a number of places throughout the world. In the United States, Florida has especially abundant phosphate resources, largely as fluorapatite, Ca5(P04)3F, as well as hydroxyapatite, Ca5(P04)30H. These phosphate minerals are too insoluble to serve directly as fertilizers and are treated with phosphoric acid and sulfuric acid to make superphosphates that are much more soluble and available to plants ... 

The value of langbeinite as a fertilizer is enhanced because, in pure form, it contains 18.8 wt % potassium, 11.7 wt % magnesium, and 23.0 wt % sulfur. AH three elements are essential nutrients for plant growth. Commercial grades contain ca 97 wt % mineral the remaining 3 wt % consists of water-insoluble clays and residual sodium chloride. 

At least thirteen mineral elements have been shown to be essential in human nutrition. These include calcium, magnesium, sodium, potassium, phosphorus, sulfur, and chlorine (principal mineral elements), and iron, copper, iodine, manganese, cobalt, and zinc (trace elements). It is uncertain as to whether fluorine, aluminum, and boron are essential nutrients. 

Soils deficient in sulfur do not support plant growth well, largely because sulfur is a component of some essential amino acids and of thiamin and biotin. Sulfate ion is generally present in the soil as immobilized insoluble sulfate minerals, or as soluble salts that are readily leached from the soil and lost as soil water runoff. Unlike the case of nutrient cations such as K, little sulfate is adsorbed to the soil (that is, bound by ion exchange binding) where it is resistant to leaching while still available for assimilation by plant roots. 

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