They are water soluble substance rich in nutrients which are added to soil to enhance the fertility of the soil.
Organic fertilizers: Those fertilizers which are obtained from theliving source are known as organic fertilizers. They are two types:
Green manure is defined as the practice of growing, ploughing under and mixing of green plants with soil to improve the fertility of the soil and ultimately crop productivity.
It is a kind of natural fertilizer which is prepared by mixing of cattle dung, poultry dropping and crop residues like remnants of straw, rotten vegetables, etc. The mixture is stored in a pit. Sometimes, lime is added to the pit containing mass to make a good kind of fertilizer. Gradually, by the action of micro-organisms, decomposition takes place and converts it into compost. It provides most of the nutrients required by plants and enhances the fertility of the soil.
Chemical fertilizers: The fertilizers prepared artificially in industry by using minerals are called chemical fertilizers.
Example: Ammonium sulphate Urea
Example: Ammonium phosphate ; Calcium super phosphate
Example: Potassium chloride Potassium nitrate
On the basis of number of primary nutrients supplied, fertilizers are of following three types:
Example: Potassium chloride
Environmental deterioration due to unscientific and improper use of chemical substance is called chemical pollution.
The contamination of the chemicals in the environment is called chemical pollution. Pesticides and fertilizers are the factors which causes chemical pollution. When the chemical fertilizers like nitrate fertilizer is used in excess amount, it may not be completely absorbed by the crops in the soil. Thus, the rain water will wash it off and accumulates it in ponds and lakes. As a result, there will be the overgrowth of unnecessary of weeds and algae. These weeds and algae will consume all the food and oxygen in the water. Consequently, the aquatic animals will die with the lack of food and oxygen.
The deficiency of nitrogen causes reduction of yield and leaves turn from green to yellow. The deficiency of phosphorus causes poor root growth and purpling of leaves and plant growth will be the stunned and delayed in the fruit ripening. The deficiency of potassium causes hindering in protein synthesis and cell division leaves and buds wither and immunity is decreased.
Nitrogen is necessary for the synthesis of chlorophyll and protein which helps for the growth of the plant. The urea fertilizer supplies nitrogen in the soil.
The two ways to control chemical pollution are: a. The use of chemical substances like CO, lead, SO2 etc. should be reduced. b. The use of chemical pesticides in vegetables and other crops should be reduced.
Nitrogen fertilizer is essential for the growth of the plants.
A fertilizer that contains the major elements Nitrogen, Phosphorus and Potassium is called NPK fertilizer. Ammonia nitrate (NH4NO3) is a chemical fertilizer that contains nitrogen. Ammonia phosphate [(NH4)3 PO4] is a chemical fertilizer that contains phosphorus.
The colored food stuffs contain different types of coloring agents i.e. chemicals which can cause chronic disease like cancer, rheumatic pain, asthma, etc. So, colored food stuffs are not safe to eat.
Compost manner is the kind of organic fertilizer which is made by decaying of grasses, straw, cow dung etc. in pits for few months. It can provide entire elements which are necessary to the plants.
The substances which are used to increase the fertility of soil is called fertilizer. They are of two types:
i. Organic fertilizers
ii. Inorganic chemical fertilizers
The following effects are seen in the plant due to deficiency of potassium are: i. Less growth and development of flower. ii. Wilting and withering of leaves. iii. Reduces the disease resistant power of plants. iv. Disturbances in manufacturing protein and cell division.
The two following potassium containing fertilizers are: i. Potassium chloride (KCl) ii. Potassium nitrate (KNO3)
|Organic Fertilizers||Inorganic Chemical Fertilizers|
Whicih of the following is not inorganic insecticides?
Those fertilizers which are obtained from the living source are known as ______.
All those substances which are rich in nutrients for plants and that are added in soil to enhance the fertility of soil are called ______.
Ammonium nitrate is a ______.
An organic substance obtained from the decomposition of animal remains, poultry droppings and dead plants is called ______.
The complete fertilizers are also called ______.
Fertilizers which contain all the three nutrients i.e. nitrogen, phosporus and potassium as primary plant nutrients are called ______.