“No man is an island no man stands alone”, no entity on Earth can survive without interacting with abiotic factors. Organisms strive daily for survival. Their survival is predicated on receiving enough energy and nutrients to carry out metabolism and maintain homeostasis. Survival of a species is determined by the fitness of an organism within its environment and how successful it is at passing its genes on to its progeny. When examining the interactions that must be carried out each day it is observed that living systems require some basic materials that are recycled again and again throughout the ecosystem.
Many of these materials are nutrients, the components ingested by an organism which are necessary for cell maintenance, …show more content…
This cycle is unique in that the atmosphere is composed of 78% nitrogen, but it cannot be used in its atmospheric form. Nitrogen is also found in sedimentary rock and bodies of water. Although the element is abundant it must be converted into a different form prior to entering the biosphere. To be cycled in the biosphere, nitrogen (N2) is converted into a usable form by nitrogen fixing bacteria found in legumes. When nitrogen moves from the atmosphere into the lithosphere Rhizobium bacteria living in symbiosis with these plants begin the process of nitrogen conversion to ammonia (NH3), or cyanobacteria in water systems convert (N2). Through the process of nitrification ammonia is then transformed into nitrite and then on to nitrate which serve as macronutrients for plants as they form proteins, nucleic acids, or ATP. Consumers that eat these plants use nitrogen in the process of protein synthesis and store nitrogen in their tissues. When organisms release wastes products or die, the nitrogen is broken down and returned to the soil where decomposing bacteria convert nitrogen rich compounds into simpler ones. The final step in this cycle is denitrification. During the final phase of the cycle denitrification occurs and is performed by a variety of decomposers. Denitrification involves the transformation nitrites and nitrates back into nitrogen gas, which is then released into the atmosphere where it is stored until need again. Small but significant amounts atmospheric nitrogen is converted when lightning occurs, forest fires and lava flows. Humans have helped double the amount of fixed nitrogen released into the biosphere by burning of fossil fuels, using artificial fertilizers, and cultivating more legume