Water helps control body temperature. It is needed for our cells to function. NUTRITION IN PLANTS There are seventeen elements that are important to plant’s growth and survival. It is divided by two main groups, these are non-mineral and mineral. Hydrogen, oxygen, and carbon are the non-mineral nutrients.
Acidic soil • The soil either lacks phosphorus, magnesium or calcium. Alkaline soil • The soil either lacks zinc, copper or iron. You can use this scale to see which minerals your soil has and does not depending on its pH value: There are plants suitable for different pH
According to Neary (2006), nitrogen has traditionally been considered one of the most important elements in the soil for the plant nutrient. It is an essential component of the proteins that build cell material and plant tissue. Plants, especially crops need a lot of nitrogen because it is part of many important compounds, including protein and chlorophyll. Nitrogen is changing its chemical form continually and moving from plants through animals, soils water and the atmosphere (Wiederholt and Johnson, 2005). Plants respond to nitrogen in soil in many ways.
It also appears in numerous of other reactive compounds such as in ammonia, 〖NH〗_3, and it is a fundamental component of life to all organisms on Earth (wisegeek.org). Nitrogen is one of the most essential nutrients for plant growth and it is the most suitable nutrient that producer can control. Despite the fact that nitrogen is most abundant elements on earth, nitrogen deficiency is presumably the most common nutritional problem affecting plants since it is easily lost from the soil system. In addition to the fact that atmospheric nitrogen (N_2) is not accessible by most plants and they need nitrogen fixating microbes or nitrogen fixation from lightening strikes that change N_2 into nitrites and then other microbes that change it into nitrates. It is mostly in the nitrate form that is available plants to use.
Potassium (K) is one of the sixteen essential nutrients required for plant growth and reproduction. It is not only a constituent of any plant structure or compounds but also plays a vital role in photosynthesis, translocation of ions and their balance, regulation of stomatal opening and closure, water use efficiency and activation of at least 60 enzymes. Potassium is the most abundant cation in the cells of non-halophytic higher plants (Maathuis et al., 1997). It is absorbed by plants in higher amounts than any other mineral element except nitrogen (Daliparthy et al., 1994). Kafkafi (1990) suggested that the luxury storage of K by cotton plant can be both beneficial for higher yields and a cheap source of insurance against possible K-deficiency
Chemical fertilizers contain all the essential nutrients required by the plants that are already broken down to their simplest forms. These essentials can often get leached by simple irrigation. Nitrogen, particularly, settles to the bottom of the plants( usually near the roots) and seeps down and becomes a part of the ground water. this can contaminate the groundwater for decades and eventually affect both plants and animals. Further, chemical fertilizers are not just made of the key nutrients, but there are other salts and compounds mixed too that are not absorbed by the plants.
Introduction Soil has been used for many years for cultivating crops for consumption, But in recent years there has been a decrease in the yield of crops due to soil related problems. There has been an increase in salinization of soil, nutrient depletion and soil erosion. Around 950 million hectares of salt-affected lands occur in arid and semi-arid regions, which is 33% of the world's potentially arable land. Nutrient depletion is also has a very severe effect on the economy of the world, specifically Sub-Saharan Africa. Depletion rates per annum were estimated at 22 kg of Nitrogen, 3 Kg of Phosphorous, and 15 Kg of Potassium, per hectare (Sanchez, 2002).
An article named Role of Chemistry 's in Feeding Growing World says, “A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use”( Chemistry2011.org). Fertilizers are added to the soil in which crops are growing to provide nutrients needed by the plants. Both organic and inorganic fertilizers supply the nutrients required for maximum growth of the crop. Inorganic fertilizers contain higher concentrations of chemicals that may be in short supply in the dirt. The major nutrients in inorganic fertilizers are nitrogen, phosphorus, and potassium.
1.1 SOIL EROSION: 1.1.1. SOIL: Soil contains minerals, water, air, natural matter, and life forms that are the rotting. It forms at the surface of land – it is the “earth’s skin.” Soil has capability to support plant life and is invigorating to life on earth. Also it is capable of supporting all civil engineering structures. Soil is the prime source-for food.