Nutrient Cycling | Environment for UPSC 2024 (Pre & Mains) PDF Download

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NUTRIENT CYCLING 
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NUTRIENT CYCLING 
The amount of nutrients, such as carbon, nitrogen, 
phosphorus, calcium, etc., present in the soil at any 
given time, is referred to as the standing state.  
It varies in different kinds of ecosystems and also on a 
seasonal basis.  
What is important is to appreciate that nutrients which 
are never lost from the ecosystems, they are recycled 
time and again indefinitely.  
The movement of nutrient elements through the 
various components of an ecosystem is called 
nutrient cycling.  
Another name of nutrient cycling is biogeochemical 
cycles (bio: living organism, geo: rocks, air, water). 
Energy flows through an ecosystem and is dissipated as 
heat, but chemical elements are recycled. 
 Nutrient cycles are of two types: (a) gaseous and (b) 
sedimentary.  
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NUTRIENT CYCLING 
The amount of nutrients, such as carbon, nitrogen, 
phosphorus, calcium, etc., present in the soil at any 
given time, is referred to as the standing state.  
It varies in different kinds of ecosystems and also on a 
seasonal basis.  
What is important is to appreciate that nutrients which 
are never lost from the ecosystems, they are recycled 
time and again indefinitely.  
The movement of nutrient elements through the 
various components of an ecosystem is called 
nutrient cycling.  
Another name of nutrient cycling is biogeochemical 
cycles (bio: living organism, geo: rocks, air, water). 
Energy flows through an ecosystem and is dissipated as 
heat, but chemical elements are recycled. 
 Nutrient cycles are of two types: (a) gaseous and (b) 
sedimentary.  
Page 4


 
NUTRIENT CYCLING 
The amount of nutrients, such as carbon, nitrogen, 
phosphorus, calcium, etc., present in the soil at any 
given time, is referred to as the standing state.  
It varies in different kinds of ecosystems and also on a 
seasonal basis.  
What is important is to appreciate that nutrients which 
are never lost from the ecosystems, they are recycled 
time and again indefinitely.  
The movement of nutrient elements through the 
various components of an ecosystem is called 
nutrient cycling.  
Another name of nutrient cycling is biogeochemical 
cycles (bio: living organism, geo: rocks, air, water). 
Energy flows through an ecosystem and is dissipated as 
heat, but chemical elements are recycled. 
 Nutrient cycles are of two types: (a) gaseous and (b) 
sedimentary.  
 
CARBON CYCLE 
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NUTRIENT CYCLING 
The amount of nutrients, such as carbon, nitrogen, 
phosphorus, calcium, etc., present in the soil at any 
given time, is referred to as the standing state.  
It varies in different kinds of ecosystems and also on a 
seasonal basis.  
What is important is to appreciate that nutrients which 
are never lost from the ecosystems, they are recycled 
time and again indefinitely.  
The movement of nutrient elements through the 
various components of an ecosystem is called 
nutrient cycling.  
Another name of nutrient cycling is biogeochemical 
cycles (bio: living organism, geo: rocks, air, water). 
Energy flows through an ecosystem and is dissipated as 
heat, but chemical elements are recycled. 
 Nutrient cycles are of two types: (a) gaseous and (b) 
sedimentary.  
 
CARBON CYCLE 
Carbon cycling occurs through atmosphere, ocean and 
through living and dead organisms.  
According to one estimate 4 × 1013 kg of carbon is fixed 
in the biosphere through photosynthesis annually. 
 A considerable amount of carbon returns to the 
atmosphere as CO2 through respiratory activities of 
the producers and consumers. 
 Decomposers also contribute substantially to CO2 pool 
by their processing of waste materials and dead 
organic matter of land or oceans.  
Some amount of the fixed carbon is lost to sediments 
and removed from circulation. 
 Burning of wood, forest fire and combustion of organic 
matter, fossil fuel, volcanic activity are additional 
sources for releasing CO2 in the atmosphere.