Human impact on nitrogen cycle , Biology

Assignment Help:

Human Impact on Nitrogen Cycle

Human activities are profoundly affecting the cycling of nitrogen in nature. Over 30 x 106 metric tons/yr. of N2 is fixed in the commercial production of fertilisers, an amount almost equal to that fixed biologically. The use of N2 fertilisers affect the distribution of N2 on earth. Much of the nitrogen in the harvested crops becomes animal and human waste in sewage waters and eventually enters the aquatic ecosystem through runoff and leaching. Nitrogenous compounds leached into the groundwater may be abundant in irrigation and drinking water where they can cause serious health hazards. Nitrogenous compounds entering the lakes have fertilising effect resulting in algal blooms and promote cultural eutrophication.

Excessive growth of phytoplankton in eutrophic lakes produces huge quantities of biomass and finally collapse due to nutrient exhaustion. The dead organisms are consumed by detrivores which use up the oxygen supply. This problem of cultural eutrophication is, however, more severe in the case of phosphorus additions rather than nitrogen. When fossil fuels are burned we add nitrogenous compounds to the air. Large quantities of nitrogen oxide (NO) are released from vehicles and most of the NU is converted to NO2 by combining with ozone (O3) in the atmosphere. NO2 is a toxic gas for 6umans and a cause of smog. It combines with water to form nitric acid, HNO3, which forms 30% of the strong acids in the acid rain.


Related Discussions:- Human impact on nitrogen cycle

Deifition, what''s the define of mitochodria

what''s the define of mitochodria

How are the transparency and functions of cornea evaluated, How are the tra...

How are the transparency and functions of cornea evaluated? Physiological roles of barrier function, refractive function (with interaction of tear film), response to wound and

Is acetylcholine found in brain, Q. Is Acetylcholine found in brain? Ace...

Q. Is Acetylcholine found in brain? Acetylcholine is found in many parts of the brain having particularly high concentrations in the cerebral cortex, limbic system, basal, foreb

Describe about defecation reflex, Q. Describe about defecation reflex? ...

Q. Describe about defecation reflex? An example of a reflex having an autonomic (and somatic) component is the DEFECATION REFLEX: The rectum is generally empty, but when fec

State the versions of binocular movements, State the Versions of Binocular ...

State the Versions of Binocular movements Versions are movements of both eyes in the same direction. a) Dextroversions: Movements of both eyes to'the right side. b) Levov

Enzyme - linked immunosorbent assay (elisa), E n z y m e - l...

E n z y m e - linked immunosorbent assay (ELISA):   ELISA in its var io us modifications e.g. plate ELISA, sandwich ELISA, competitive ELISA, ELISA strip or

Describe the principles of dna sequencing, The ability to sequence DNA has ...

The ability to sequence DNA has led to a revolution in molecular biology. a) Describe the principles of DNA sequencing. b) A single sequencing reaction yields at best 1500 ba

What are cerebrovascular accidents, Q. What are cerebrovascular accidents? ...

Q. What are cerebrovascular accidents? The Cerebrovascular accident (CVA), as well known as stroke, is the generic name given to infarction (tissue and cellular death by hypoxi

Functions of insulin, FUNCTION S - (a) It is antagonistic to glucagon....

FUNCTION S - (a) It is antagonistic to glucagon. Insulin decreases the level of glucose in the blood. It acts by increasing the rate at which glucose is transported out of the

Explain metameric in detail., Explain Metameric in detail. A body plan ...

Explain Metameric in detail. A body plan which consists of a series of identical units, metameres, repeated down longitudinal axis of the animal. Every metamere contains identi

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd