Fertilizer artificial

In order to appreciate the function of artificial fertilizers it is instructive to look at plant nutrition and some natural cycles which replace nutrients removed from the soil by growing crops. 

Plant nutrition is therefore concerned with ensuring that the growing crop receives adequate supplies of these elements in addition to sunlight and water. The plants themselves participate in a number of natural recycling processes. The carbon and nitrogen cycles are examples and are summarized below. 

Nitrogen input to soil Microbiological fixation Atmospheric electrical discharge Nitrogen loss from the soil Growing crops 

Therefore to maintain soil fertility the difference must be made up by the application of artificial fertilizers. 

Nitrogen fertilizers are based on the Haber process for producing ammonia from nitrogen and hydrogen. Although this is a very energy-intensive process it is well established, and full benefit has been taken of the economy of scale effect (see section 4.7, Volume I). The ammonia is then converted into ammonium salts and nitrates  

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Vegetables are also a prime source of nitrate, and variations in their nitrate levels occur due to conditions employed during the cultivation and storage processes. The nitrate concentration in surface water has increased due to increased use of artificial fertilizers, changes in land use and disposal of waste from intensive fanning. Nitrate is readily converted in mammalian systems through bacterial and mammalian enzymes to nitrite which can react with amines, amides and amino acids to form NOC. 

Organic gardening is not just a matter of replacing chemicals such as artificial fertilizers and pesticides with more natural products, as it is often simplistically described. There is a great deal more to it than that, in both theory and practice. 

Despite the limitations of organic gardening, there are many proven techniques that will reduce the need for artificial pesticides and improve soils without artificial fertilizers. We will now examine some of these. 

Before the availability of artificial fertilizers in the mid-19th century, farms were traditionally organic, with recycling of animal waste, and perhaps with the application of lime on acid soils. Agricultural chemical analysis may have begun with Carl Wilhelm Scheele (1742-1786), the Swedish pharmacist who isolated citric acid from lemons and gooseberries and malic acid from apples. In France, Nicolas Theodore de Saussure (1767-1845) studied the mineral composition of plant ash, and in Britain, Sir Humphrey Davy... 

With the twentieth century came enormous progress in the development of the chemical industry. Chemistry transformed agriculture. Artificial fertilizers provided the means of feeding the enormous, growing population of the world. Chemistry transformed communications and transportation. It provided advanced materials, like silicon for computers and glass for optical fibers it developed more efficient and renewable... 

Today the very large amounts of nitrogen fixed by crop and forage legumes probably exceeds the substantial input from artificial fertilizers worldwide. That fixed in natural ecosystems is probably of the same order of magnitude. 

Cadmium is a heavy metal with similar chemical properties to zinc, but is much less common in the environment than zinc. Cadmium occurs in igneous rocks and some sedimentary rocks, and is generally associated with zinc ore minerals like sphalerite, and with a range of copper ore minerals. Traces of cadmium are often present in artificial fertilizers, and this heavy metal may accumulate in soils in areas that have been used for agriculture for long periods. 

In 2008, more than 95 percent of all the phosphate rock mined in the United States was used in the manufacture of fertilizer and animal feed supplements. Modern farmers use enormous amounts of synthetic (artificial) fertilizer on their crops. This synthetic fertilizer contains nitrogen, phosphorus, and potassium, the three elements critical to growing plants. These elements normally occur in the soil, but may not be present in large enough amounts. Adding them by means of synthetic fertilizer helps plants grow better. Most farmers add some form of synthetic fertilizer to their fields every year. This demand for synthetic fertilizers accounts for the major use of phosphorus compounds. 

By far the most important compound of potassium is potassium chloride (usually referred to as potash ). At least 85 percent of that compound is used to make synthetic (artificial) fertilizers in the United States. The figure is even higher worldwide—93 percent. The chemical industry is also a primary user of potash resources. 

The use of artificial fertilizers in agriculture also generates atmospheric nitrogen compounds that can reach the stratosphere and possible destroy ozone. 

Proteome of Placenta. In addition to the study of proteomics of amniotic fluid, the study of the placenta proteome has been undertaken to determine the health of the fetus and the effect of artificial fertility methods on changes in the fetus. Several proteins have been identified that may be useful in deciding the use of different artificial fertility methods. 

In recent years, the concentration of nitrate ions in groundwater has greatly increased due to excessive use of artificial fertilizers and for other reasons such as the increase in livestock farming. This is a serious problem. Nitrate ions are... 

An important property of soil is its fertility. Fertility is the ability of soil to provide the plants with such conditions during their vegetative period that will ensure their growth, development and yields. The soil fertility depends on both the properties of the soil itself (natural fertility) and the activity of man in cultivating the soil (artificial fertility). 

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