Several types of bacteria can be found in the soil. Each type serves its own function in the earth's ecosystem. Bacteria in the soil perform such vital functions as improving water flow, suppressing diseases and improving the nutrient quality in the soil. Don't fret over their scientific names; there are some common names that anyone can understand.
Nitrogen Fixed Bacteria
Nitrogen-fixed bacteria have symbiotic relationships with several plants found in the forest. They form on the roots of such plants as clover, lupin and locusts. When they form they create a nodule that sits on the root they colonise. The plant feeds the bacteria with carbon compounds while the bacteria converts nitrogen from the air into a usable form for the plant. When the plant dies and decays the nitrogen is released into the soil, increasing the soil's nitrogen content.
Nitrifying bacteria assist in converting ammonium into two types of nitrogen compounds called nitrates and nitrites. These nitrite and nitrate compounds differences lie in the number of oxygen atoms they have. Nitrite has one nitrogen atoms and two oxygen atoms. Nitrate has one nitrogen atoms and three oxygen atoms. Nitrate works well in producing crops so farmers leach it from the soil and use chemicals to keep the nitrite specific bacteria from converting ammonium into nitrite.
Denitrifying bacteria convert nitrate into nitrogen or nitrous oxide, which has two nitrogen atoms and one oxygen atom. This bacteria is anaerobic, which means they can survive without oxygen being in the air. This bacteria is found in saturated soil or in the aggregate of soil.
Actinomycetes act as nature's recyclers. This bacteria is known as a hypha, which is similar to fungus. It has the ability to break down many compounds in the soil such as cellulose. One major difference between this bacteria and fungi is that the actinomycetes can function when the pH of the soil is high. This means the soil is very alkaline. The fungi only operates in low pH soil.
Azobacter are similar to nitrifying bacteria. They can convert nitrogen from the atmosphere into ammonium that plants can use. This bacteria can only perform this function when carbon and a high pH are present. Also high phosphorus and low oxygen levels must be present as well.