Elements Necessary for Growth
Element necessary for growth Sources Deficiency
Nitrates in soil (fixed by lightening, bacteria, or in the Haber process; or from the decay of animal/plant remains) Chlorosis (yellow or pale green colour), stunted growth
Phosphorus Fertilizers and organic manure Retarded growth
Potassium Clay and humus particles, fertilizers Stunted growth, leaves fall off
Sulphur Humus, fertilizer Poor cell growth, chorosis
Calcium Lime, gypsum Poor development and cell growth, stunted growth
Magnesium Soil particles and humus Inability to make chlorophyll so lacking green colouring
Plants require many elements to grow properly such as oxygen, carbon dioxide and hydrogen which are found in water and air.
The most profuse element in the earth’s atmosphere is nitrogen; it makes up 78% of the troposphere. Animal and plants cannot absorb nitrogen directly it has to be converted into compound they can use through the process of the nitrogen cycle. The first step in the nitrogen cycle is nitrogen fixation where specialize bacteria covert the nitrogen gas (N2) into ammonia (NH3) which the plant can then use. The second process is nitrification; ammonia is converted into nitrite ions which the plants absorb as nutrients. Ammonification is the third process once all the plants and animals have used the nitrogen, decomposing bacteria covert the nitrogen-rich waste compounds into simpler ones. Last but not lest is denitrification which is the final process in which other bacteria convert the simple nitrogen compounds back into nitrogen gas (N2), which is then release back into the atmosphere and the cycle begins again.
Nitrogen is one of the most important essentials elements required for healthy plant growth. It forms 40-50% the dry matter protoplasm (the living substance of plant cells); nitrogen is also contained in proteins, other organic compounds and it is the basic component of chlorophyll the compound in plant which use sunlight energy to produce sugars during the process of photosynthesis .A lack of nitrogen can cause deficiency in plants, therefore this is important for a plant’s survival.
Soil is defined as the upper layer of the earth’s surface; it is the source for plants to get nutrients and a place for them to send their roots down and anchor themselves. Soil is made up of minerals, organic matter, liquids (H2O) and gasses such as CO2.
Functions of Soil:
Soil is a vital component of the nutrient cycling. It can take in nutrients in forms, which in which other organism cannot use and processes them into usable forms.
Soil helps to manage water by holding moisture, controlling the flow and drainage. It is also like a sponge absorbing up water and when plants need it, the water is release back out.
Provides homes for many different organisms and plant.
It helps filter pollutants from the water and air to keep the quality of our air and water safe.