What Are Biogeochemical Cycles and How Are they Important in Ecosystems?
Introduction – Lets think of the biosphere as being composed of 4 compartments just as the ground level of a home might be divided into 4 rooms. The four compartments are: 1. the bodies of organisms (producers, consumers and decomposers) 2. the air or atmosphere 3. the soil 4. the water (streams, lakes and the oceans) Molecules that serve as raw materials or building blocks that make up the bodies of humans and other organisms become part of the general environment again after the organism dies. These materials such as carbon, nitrogen and phosphorus cycle through move through the other compartments of the environment such as air, water and the soil and eventually become available to organisms again. A. The Water Cycle The water cycle, shown below, is a good example of the principle of materials moving among compartments. See Fig. 43.13 – The Water Cycle Note the important processes involved in the water cycle: transpiration from land plants to the air, evaporation from water to the ai