What is Environment ?......
Well environment means surroundings, mainly a term used for conditions in which organism live and thus consist of air , water food and sunlight which are based on the needs of all living beings and plants to carry out their life functions . The environment also includes other living organisms , temperature , wind , rainfall , etc..........

Man has always inhabited two world's . One is natural world of plants , animals, air , water and soil of which man himself is a part ; and other is the man-made world of social institutions and artifacts

which he has created for himself by using science and technology . Thus environment includes everything around the organisms, i.e non-living and living things.......
Non-living environment consists of air , water and land , while the living environment is built up of other organisms. Any external force , condition which affects the organisms in a way is known as factor and sum of all such factors constitutes environment........
There are three segments in which environment is been divided ...... which will study in detail in my other posts, which are :
ATMOSPHERE , HYDROSPHERE , LITHOSPHERE.

WHAT IS ECOSYSTEM ?

In a given area , the biotic assemblage of all organisms , plants as well animals interacting with their physical environment in such a manner that there is a flow of energy leading to clearly defined trophic structure , biotic diversity and material cycles within a system , known as an Ecosystem.....

An Ecosystem may be natural as a pond , a lake , a river , an ocean or it may be an artificial such as dam , garden etc... It could be a small drop of water or a large sea.... It has two major components :

(1) Abiotic components : It can be divided into the following three parts:

(a) The inorganic components such as water , carbon-di-oxide , nitrogen , calcium , sulphur , phosphorus etc.....

(b) The organic compounds such as proteins , carbohydrates , lipids and amino acids .......

(c) The climatic factors such as light , temperature , humidity , wind , soil etc.......

(2) Biotic components : the living organisms of an ecosystem are known as its biotic components , which include plants , animals and micro organisms ... The organisms are of three types :

(a) Producers : These are the autotrophic members of the ecosystem which are green plants and capable of synthesizing food from non-living simple inorganic substances.......

(b) Consumers : These are heterotrophic members of the ecosystem which eat up other living organisms... The other animals includes which merely depends on the food produced by producers......

(c) Decomposers : These include micro organisms like bacteria and fungi which attack on the dead bodies of producers and consumers and decompose them into simpler compounds and also release inorganic nutrients........

WHAT IS ECOLOGY ?

Ecology is the branch of biological science concerned with the relationships and interactions between living organisms and their surroundings or environment. The term ecology was coined by combining two greek words, oikos (meaning house) and logos (meaning 'the study of ) to denote such relationships between the organisms and their environment ..... It is mainly the study relations between organisms and totality of biological and physical factors affecting them or influenced by them.

On the basis of nature of study , ecology can be sub-divided as autecology and synecology........
Autecology deals with the study of an individual organisms or species.....
while synecology deals with the study of groups of organisms which are associated together as a unit.........

All the ecological factors

are interrelated. Variations in one may affect the other . For instance an increase in temperature would certainly bring out a decrease in humidity values . Increased light intensity , will affect rate of photosynthesis ....... Thus ecology is just an study of interrelation between various organisms and physical factors........

WHAT IS AQUATIC ENVIRONMENT ?

Here term environment means surroundings it can be associated as a composite term for the conditions in which organisms live . Thus aquatic environment means environment inside and outside water. The total environment is composed of the biotic and abiotic i.e. living and non-living environment....
Non-living environment consists of physical and chemical components of ecosystem. The physical factors of environment are temperature , light , water movement , humidity , water current , pressure , soil , and micro climate . Chemical factors include atmospheric gases such as O2 , CO2 etc , dissolved gases , pH , nutrients and food. Living organisms of an aquatic ecosystem can be divided into three categories-
(1) Benthos - Flora and Fauna found at the bottom of the sea or lake , such as worm , clam and crayfish.......
(2) Nekton - Aquatic animals that are able to swim and move independently of water currents , such as fishes......
(3) Plankton - The small and microscopic organisms drifting or floating in sea or fresh water , such as diatoms , protozoa , small crustaceans, and the eggs and larval stages of larger animal. They can be further divided into zooplankton (microscopic animals) and phytoplankton (microscopic plants such as algae)..........

HOW MAN AFFECTS HIS ENVIRONMENT ?

Every living species of animals or plants influences its environment and in turn gets affected from it . The magnitude of influence done by plants and animals is limited to a certain extent due to natural barriers , further they cannot modify their environment . But man is an exception , he can modify his environment to satisfy his needs......

From the start of human civilization , man started interfering with the environment. He devasted forests for wood , bringing land for cultivation and to have soil which has eroded by natural processes.
He killed animals -the gentle ones for food and fierce ones, for safety. He polluted water , air and soil by chemical garbages from their houses and factories. However all these activities did not affect the environment in a serious way for a long time , because population was not so high and nature's self cleansing and purifying ability keep the environment undeteriorated......

After the scientific and industrial revolution in the past , man started to affect his environment in a more serious way . Man's effort to control the nature , leads imbalance in the ecosystem. Large crowded cities , huge industrial installations every year , more and more comfort requirements all these leads to what is called environmental pollution....

Primitive man used natural resources to satisfy his basic needs of air , water , food and shelter . These natural and unprocessed resources were readily available in the biosphere , and residues produced by there use were generally compatible with , or easily assimilated by the environment . But as the acquired needs of man increases , it increases the complexity of resourse production chain , and mass and complexity of the pollutants generated.....

All the above mention activities of man raised problems like ecological imbalance , environmental degradation , disruption of earth's natural ecosystems , depletion of protective ozone layer , global warming and sick environment....... 

For more of such hot topics read my other posts here :

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