Decomposers, as the name suggests, decompose dead plants or animals into simple compounds. They feed on dead producers from the first levels or consumers from other three levels. Breaking them down, decomposers release nutrients that producers can use. In an ecosystem with four levels, the first level are producers, such as plants and algae. On the second trophic level, there are primary consumers, herbivores that eat plants, for example, a deer, a rabbit, a grasshopper. The next trophic level belongs to secondary consumers that eat herbivores, for example, a wolf, a fox. The highest level is tertiary consumers that eat carnivores, for example, a bear, an eagle.
The process that is responsible for the movement of carbon atoms from the biosphere to the geosphere is called sedimentation. Carbon enters the geosphere or lithosphere through the biosphere when dead organic matter becomes incorporated into the soil that turns the shells of calcium carbonate to become limestone through the process which is called sedimentation. This sedimentation process is very necessary for the formation of different types of minerals such as limestone, fossil fuels etc.
Reforestation of agricultural land can improve biodiversity, which can result in increased primary production, reduced susceptibility to invasion by exotic species and increased ecological resistance to pressures such as climate change