Nitrogen cycle The nitrogen cycle is the biogeochemical cycle by … - Vidyadip

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Nitrogen cycle
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among the atmosphere, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification, The majority of Earth’s atmosphere (78%) is atmosphere nitrogen, making it the largest source of nitrogen.

However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition, Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle. Human modification of the global nitrogen cycle can negatively affect the natural environment system and also human health.

1. Why nitrogen cycle is called bio-geochemical cycle?
2.Why is nitrogen cycle important to us?
3. Name important process of nitrogen cycle.
4.What can affect the nitrogen cycle negatively?
5.Which human activities change the nitrogen cycle?

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Answer

1.Nitrogen cycle is called bio-geochemical cycle as it undergoes biological as well as geochemical processes.
2.Nitrogen cycle is important to us as nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition.
3.Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification.
4.Human modification of the global nitrogen cycle can negatively affect the natural environment system and also human health.
5.Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle.

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