Question:
Explain the biogeochemical cycle. What is the significance of the reservoir in this cycle? With a reservoir situated in earth’s crust, give an example of a sedimentary cycle.
Answer:
The movement of nutrient molecules through different components of an ecosystem is known as a biogeochemical cycle. There are two types of nutrient cycles – Sedimentary and gaseous. For the gaseous type of cycle, the atmosphere is the reservoir(nitrogen cycle) and for the sedimentary cycle – the crust of the earth is the reservoir (phosphorous cycle). The function of the reservoir is to be able to compensate for the deficiency that takes place due to the inequality in the flow of efflux and influx. Various environmental factors such as temperature, moisture in the soil, pH etc govern the rate of liberation of nutrients into the atmosphere. The phosphorus cycle is an example of the sedimentary type of cycle as it moves from land and approaches the bottom of the seas and reverts to the land, whose natural reservoir is the crust of the earth. Phosphorous is contained in rocks in the form of phosphates. Soil erosion and weathering cause them to enter water bodies. Movements of the crustal plates lead to seafloor being uplifted and hence exposure of phosphates on the land surfaces. Weathering over a period of time liberates phosphates, which are softened in soil and seeped by plant roots. Herbivores and other entities attain this element from producers. Decomposition of dead organisms and waste products by phosphate-solubilizing bacteria release phosphorous.
No comments:
Post a Comment