ES101 Lecture Notes - Lecture 18: Nitrogen Fixation, Nitrogen Dioxide, Nitrogen Cycle

• School: WLU
• Department: Environmental Studies
• Course: ES101
• Professor: Edmund Okoree

Document Summary

Nitrogen: atmospheres most abundant element making up 78% of troposphere. Crucial component of proteins, vitamins and nucleic acids however nitrogen gas cannot be absorbed and used directly by animals and plants. Two natural processes enable the transfer of nitrogen to organisms:( convert n2 gas): Lightning: causes atmospheric electrical discharge in the form of lightning. This causes nitrogen and oxygen(02) in atmosphere to react and produce (no) nitrogen oxide. Bacteria in aquatic systems and soil ( nitrogen fixation): processes these bacterias do can convert n2 into compounds useful as nutrients for plants and animals. Plants and animals return nitrogen rich wastes to environment and dead bodies. Through ammonification decomposer bacteria convert this detritus into simpler compounds such as water soluble ammonium salts. Nitrogen leaves soil in denitrification step in which other specialized anaerobic bacteria in soil and bottom sediments of lakes convert nh3 back into nitrate and nitrite ions and then into nitrogen gas and nitrous oxide gas.