What is the Environment?
In simple words, we can say, everything which surrounds us is called the environment.
The word “environment” is derived from the french word “environ” which means encircle.
Types of Components of the environment
In a basic way, the environment has 2 components Biotic and Abiotic. Biotic means living components like animals, humans, trees, etc.. Abiotic means non-living components like air, sand, water, chair, etc..
In an advance way, the environment was divided into 4 types.
- Atmosphere
- Hydrosphere
- Lithosphere
- Biosphere
1. Atmosphere
It is the air that presents all around the earth. The atmosphere is composed of Nitrogen, Oxygen and other gases.
Gases volume in air
Nitrogen – 78%
Oxygen – 20.99%
Carbon dioxide – 0.03%
Other gases – 0.98%
Layers of Atmosphere
Layers of the atmosphere are divided into 5 parts they are.
1.a. Troposphere
This is the lowest layer of the earth’s atmosphere.
The layer Troposphere is present from 0 to 12 kilometers above the earth.
All the weather conditions happen in this layer.
The troposphere contains 75% of the mass of the total atmosphere.
1.b. Stratosphere
This is the second layer of the earth’s atmosphere.
The layer Stratosphere is present from 12 to 50 kilometers above the earth.
The ozone layer which absorbs the harmful ultraviolet rays of sun rays is present in the layer of atmosphere.
1.c. Mesosphere
This is the third layer of the earth’s atmosphere.
The layer Mesosphere is present from 50 to 80 kilometers above the earth.
This is the coolest layer of the earth’s atmosphere with a temperature below -143 degrees Celcius.
1.d. Thermosphere
This is the fourth layer of the earth’s atmosphere.
The layer Thermosphere is present from 80 to 700 kilometers above the earth.
Space-stations orbits in this layer.
Here air moves in tides and waves.
This is the largest layer of the atmosphere.
1.e. Exosphere
This is the top layer of the atmosphere.
The layer Exosphere is present from 700 to 1000 kilometers above the earth.
The pressure is lowest in this layer.
2. Hydrosphere
The hydrosphere includes all types of water resources like oceans, seas, rivers, glaciers and all groundwater.
70% of the earth’s surface is covered by water and only 30% is covered by land.
There are an estimated 1,386 million cubic kilometers of water available on earth. From which 97.5% of water is saltwater or ocean water and only 2.5% is freshwater.
3. Lithosphere
The Lithosphere is the solid rock that covers the earth. This includes the crust and uppermost part of the mantle.
The mountains and sea floors are included in the lithosphere.
There are two components of the lithosphere they are
Oceanic lithosphere
It is associated with oceanic crust and exists in the ocean basins.
It is about 50 to 100 km thick.
Continental lithosphere
It is associated with continental crust and it exists in all the land which not covered by water.
The continental lithosphere is about 40 to 200 km thick.
4. Biosphere
The biosphere is very unique, and it is the combination of atmosphere, hydrosphere, and lithosphere where humans, animals, plants, etc. lives.
This is absent in north and south poles.
For life, here energy comes from the sun, nutrients come from, air, water, and soil. The same sources are recycled again and again to continue life.
The extreme range of biosphere is 10 km above sea level and 8 km depth in oceans.
