Our Environment- Part 1

-> The physical, chemical and biological conditions of the region in which an organism lives is called its environment.

The environment has three main components:-
* Physical surroundings- soil, air and water bodies.

* Living organisms- plants, animals, decomposers (bacteria and fungi).

* Meteorological factors (or climatic factors)-sunlight, temperature, rainfall, humidity, pressure and wind speed.

 

-> Waste- Waste (or Wastes) are unwanted or unusable materials.

In other words, Waste is any substance which is discarded after primary use, or is worthless, defective and of no use.

These are two types:-

(i) Biodegradable Waste- Those waste materials which degrade or break down in a natural

manner by a biological process is called

biodegradable waste.

These substances are decomposed through the actions of fungi, bacteria, and other living organisms.

Note:- Temperature and sunlight play an important role in the decomposition of biodegradable substances.
e.g. Food waste, trees leaves, urine and faeces matter, sewage agricultural residue, paper, wood, cloth, cow-dung etc.

-> Feces (or faeces) is the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine.

Q) Why biodegradable wastes are eco-friendly?

-> Because they transform into simpler units and then we use them as fertilizers, manure, compost, biogas and more. Therefore, this makes them eco-friendly.

Q) Difference between manure and fertilizer?

->

Fertiliser	Manure
* They are in organic substance which are manufactured in factories.	* Manure is an organic substance that is obtained from decomposition of vegetable and animal waste.
* Microbes are not needed for their formation.	* Microbes degrade the organic substances to form manure.
* Easy to transport, store and applied to crops.	* It is difficult to transport, store and applying manure to crops.
* They do not restore soil texture.	* They restore soil texture.
* They do not help in retention of water.	* They help in the retention of water.
* Nutrition like nitrogen, phosphorus and potassium are found in large quantities.	* Nutritions like nitrogen, potassium and phosphorus are are not found in large quantities.
* Excessive use of it has made the soil less fertile.	* Excessive use of it does not loose the soil fertility.
* It becomes source of water pollution and excessive use of it.	* It improve soil texture and water retaining capacity when excessive use of it.

Note- Retention of water means accumulation of excess water.

(ii) Non-biodegradable Waste- Those waste materials which cannot be broken down by natural organisms and acts as a source of pollution is called Non-biodegradable waste.

Most of the inorganic waste is non-biodegradable.

Note:- Non-biodegradable wastes that can be recycled are known as “Recyclable waste” and those which cannot be recycled are known as “Non-recyclable waste”.

-> These substances may be in solid, liquid or gaseous form. These substances are inert and simply persist in the environment for a long time or may harm the ecosystem.
e.g. DDT (dichloro-diphenyl-trichloroethane), insecticides, pesticides, mercury, lead, arsenic aluminium cans, plastics, polythene bags, glass, radioactive wastes, etc.

* These non-biodegradable wastes are major pollutants of the environment.

 Q) Why Non-biodegradable wastes aren’t eco-friendly?

-> Because they transform into solid waste in place of returning to the environment which poses a great threat to the environment and health. So, this does not make it eco-friendly and we must avoid using it.

Biodegradable	Non-biodegradable
1. Degradation process in Biodegradable waste is rapid.	1. Degradation process in Non-biodegradable waste is slow.
2. Biodegradable waste is decomposed and degraded by microbes.	2. Non-Biodegradable waste cannot be decomposed by microbes.
3. They release raw materials back to nature like fertilizers, manures, etc.	3. They do not release raw materials.
4. Biodegradable waste are not accumulated but are used up in a short time.	4. Non-Biodegradable waste often accumulate.
5. Bio-concentration or bio-magnifications does not occur.	5. Bio-concentration or bio-magnifications occurs when wastes enter food chains.

Harmful effects of Biodegradable and Non-biodegradable Substance:-

* The waste destroys the natural beauty and our surroundings become dirty.

* These wastes may block the drains creating pools of waste, which becomes the breeding sites of mosquitoes and spread the diseases like malaria and dengue.

* Decomposition of these wastes results in the production of foul smell, which spreads to the surrounding areas.

* This causes the depletion of ozone layer.

* It also cause global warming and increase

the greenhouse effect on the earth.

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