Water Cycle – First of all, transpiration occurs, which means that sun heats up the water in the tank and the liquid eventually turns into water vapor. The water vapor then goes into the air. Next is condensation; condensation is when the water in the air gets cold, which than the water turns back into liquid and the liquid forms cloud. (The cloud in our tank is the water-drops formed under the seal.) Last is precipitation. It is when the water has been condensed and the air cannot hold the liquid anymore. This causes rain formed in the tank.
Nitrogen Cycle – First is, Nitrogen Fixation, it is when nitrogen from the air, converts into ammonium by bacteria that lives in nodules in the roots or by bacteria that lives freely in the soil. Then, Urea in the tank converts into ammonia by urease enzymes in the soil, so that it can be converted into ammonium by bacteria and other micro-organisms such as fungi and archaea. The next step is volatilization, it is when large amount of ammonium in the soil form aqueous ammonia which then escapes to the air as ammonia gas. The soil organic pool contains a variety of materials, which are food for the living organisms. The organisms in the soil than turn’s nitrogen in the organic matter into ammonia and then into ammonium. As a result, it turns back into the soil when the micro-organisms die. Ammonium can also be converted into nitrite and nitrate. This is when they nitrify soil bacteria and archaea. This step is called nitrification. After is ammonium and nitrate in the soil breaks up by plants roots. During this process, ammonium gets trapped by some clay minerals. This is called ammonium fixation. The fixed ammonium released can only slowly to be used by plants and micro-organisms. When these soil micro-organisms die, they become parts of the soil organic matter pool. This cycle of ammonia and then ammonium continues.
Carbon Cycle – During the day, plants in our tank absorbs carbon dioxide and converts it into photosynthesis. During the night, some carbon is released as respiration (Carbon Dioxide). Grazing animals (E.g. Snails, Earthworms, Crickets, Most of our animals in the tank are one-celled animals.) than transform plant carbon into animal tissue and dung (Microscopic). Then some carbon dioxide is respired. Carbon is transferred to soil through dead plant tops and roots, which is known as litter. But also from leakage of living roots. Next, the dungs, exudates, and litter are decomposed by micro-organisms. Carbon is converted to microbial tissues and more carbon dioxide. Micro-organisms die and are consumed by other organisms to produce more microbial tissues and more carbon dioxide.
Plants need ammonium to produce nitrogen. Ammonium is made with one nitrogen and four hydrogen around it.
By Kyoka Matsuoka 8.2
