What is Nitrogen cycle? Defination and diagram of Nitrogen cycle. Information about the cycles of matters.
The Nitrogen Cycle
Nitrogen is an important element in living things. It is a basic component of aminoacids which form proteins.
78% of the air is nitrogen gas. Can we use the nitrogen in the air? No, plants, animals and people cannot use this nitrogen. So where do people get nitrogen from? Get nitrogen from the foods (protein).
Certain bacteria (nitrogen fıxing bacteria) in the soil change nitrogen gas into nitrogen compounds. Some of them are found free in the soiL. Others live in the root of legume plants (beans, peas, clover etc.) Plants take in the nitrogen compound through their roots in the soil. Plants use the nitrogen compounds to make proteins. When animals eat plants they take in the plant’s proteins. Then they use it to make new proteins. How does nitrogen gas return to the air?
When dead plants, animals and waste are decomposed, simple nitrogen compounds (ammonia) are produced. Plants take in these compounds from the soil. Some of the compounds are also changed by certain bacteria into nitrogen gas, which goes into the air.
There are several effects that change the balance of the nitrogen cycle in nature. The most important one of these is the growing needs of agriculture have led to increase the production of industrially fixed nitrogen. 1/3 of all the nitrogen fixation occuring taday artifically. Most of the industrially fixed nitrogen is used as fertilizer. Second one is the widespread cultivation on of legume plants (alfa, alfa, soybeans, clover). The bacteria in their roots use more atmospheric nitrogen and it raises the nitrate content of the soil. It is best for other plants.
The effects of fertilizers on the ecosystem
If a lot of fertilizer is added to the soil it can get washed down through the soil by rain and end up in streams, rivers and lakes. Fertilizers contains nitrate and other nutrients. Algae in the water take in the nitrates and other nutrients and they rapidly grow and reproduce. As a result the water turns green. This event is called eutrophication. When the organisms die, they decay. Bacteria that cause the decay reproduce so fast that they use up all the oxygen in the water. This causes the fish and other aquatic animals to die.