The elements and molecules used by living things in an ecosystem are found in the lithosphere, air sphere, hydrosphere and living sphere. These are through living things; It constantly changes places between living things and nature.

This movement begins with the conversion of inorganic substances into organic substances by green plants, and is transferred from plants to other consuming creatures. When living things die, organic matter is converted back into inorganic matter by decomposers. This cycle, which takes place in the form of matter exchange between living and non-living things, is called the matter cycle.

The main material cycles in nature are water, nitrogen, carbon and oxygen cycles. While humans intervene in these cycles with various activities, they disrupt the natural balance, cause global ecological problems and threaten living life.

Just as matter is in a cycle, energy is also in a cycle. Energy is also in relationship with matter cycles. It provides the energy that living things need to survive from the energy in the food structure through the food chain.

Green plants use solar energy to produce nutrients and oxygen by using carbon dioxide and water through a process called photosynthesis. Plants use some of the energy in the food they produce for respiration, growth, and reproduction activities. Some of the remaining energy is transferred to herbivores that feed on plants and from herbivores to carnivores that feed on herbivores.

Thus, the energy flow is transferred through the food chain from plants, which are producers, to other living creatures, which are consumers. In the event of the death of these creatures, the energy of the organic matter in their bodies is used by decomposers in their vital activities, and some substances mix with the soil and re-enter the cycle.