Select the mis-matched pair in the following and correct it.
(a) Biomagnification — Accumulation of chemicals at the successive trophic levels of a
food chain
(b) Ecosystem — Biotic components of environment
(c) Aquarium — A man-made ecosystem
(d) Parasites — Organisms which obtain food from other living organisms
Ans. (b) Is not a matching pair
Both biotic and abiotic components of environment constitute an ecosystem

An aquarium is an artificial and incomplete ecosystem in contrast to a pond/lake which are natural, self-sustaining and complete ecosystems

Flow of energy in an ecosystem can be described as follows:
• In the terrestrial environment, green plants utilize about 1% of solar energy that is falling on their leaves. This energy is converted into organic matter by plants.
• But a great portion of energy is utilized by the plants for their own metabolic needs. Just 10% of the total energy is available for primary consumers.
• Similarly, out of total energy consumed by an organism at a particular trophic level, just 10% is available for the organism at next trophic level.
• As a result, a negligible amount of energy is available for the organisms at the topmost trophic level. Due to this, an ecosystem contains at the most four trophic levels.
• There are more organisms at lower trophic than at top trophic levels. This is the general rule but some exceptions may be present.
• The food chain becomes quite complex in real world: making the food web because most of the carnivores eat many organisms.
The flow of energy is unidirectional because of two reasons. Energy always flows from the prey to the predator and not the other way round. Less energy is available as we move towards higher trophic levels. 

Decomposers break down the complex organic substances of garbage, dead animals and plants into simpler inorganic substances that go into the soil and are used up again by the plants in the absence of decomposers recycling of material in the biosphere will not take place.

Following are four activities in daily life which are eco-friendly:
(a) Walking for short distance commute: This activity helps in preventing air pollution.
(b) Using bicycle for going to school: This activity prevents air pollution which can happen when we use car for this purpose.
(c)Reusing water for mopping floor: This helps in conservation of water. Water which is collected after washing clothes and vegetables should be used for mopping the floor.
(d) Using public transport for long distance commute: In a mode of public transport, many people can travel together. This helps in reducing the number of cars and bikes on roads. Thus, it helps in preventing air pollution. 

(a) Kitchen wastes
(b) Paper wastes like newspapers, bags, envelopes
(c) Plastic bags
(d) Vegetable/fruit peels/rind
Measures for disposal
(a) Segregation of biodegradable and non-biodegradable wastes.
(b) Safe disposal of plastic bags. 
(c) Vegetable/fruit peels can be placed near trees/plants, which on decomposition will enrich the soil with nutrients.
(d) Give paper wastes for recycling.
(e) Prepare a compost pit for kitchen wastes. 

Following are some methods which should be used for waste management in fertilizer industries:
Use of catalytic converters in chimneys: Chimneys of a factory may produce many harmful gases and SPMs (suspended particulate matters). A catalytic converter helps in minimizing the harmful gases in the exhaust fume.

Electrostatic precipitators in chimneys: Electrostatic precipitator helps in minimizing SPMs in exhaust. Thus, it helps in minimizing air pollution.

Effluent treatment: All steps should be taken to prevent direct discharge of effluents into the nearest waterbody. An effluent treatment plant should be installed in the factory. It should have proper facilities for physical, chemical and biological treatment of effluent.

This will help in checking the pollution of waterbodies. It will also help in utilsing the treated water as source for irrigation. This water can also be used as drinking water after further treatment. 

The main byproducts of fertilizer industries are as follows:
Ammonia and ammonium salt, Suspended solids and ash, Acids and alkalis, Oil, Arsenic, MEA and methanol, Nitrates, Urea, Cooling water conditioning chemicals like chromate, Phosphates, biocides, etc, Cyanides and sulphides, Fluorides, Phosphates, etc.
Effect on environment:
• Suspended solids and ash add up to SPM in air. Thus, they increase air pollution. 
• Arsenic and cyanide are lethal substances. They may enter the food chain and cause diseases because of biomagnifications.
• Fluoride in drinking water is highly harmful for teeth.
• Most of the byproducts may reach water bodies and can alter the pH of water. This can be harmful for the aquatic ecosystem.