In an ecosystem, there are both biotic and abiotic factors. The biotic component includes all of the living things--bacteria, plants, fungi, animals and protists. The abiotic component includes water, oxygen, carbon dioxide, temperature, soil, minerals, solar energy and anything else that is not alive but is needed by living things in some capacity. In order for the ecosystem to be self-sustaining, there must be a cycling of materials as illustrated by the carbon cycle, the nitrogen cycle, the water cycle. However, there is also a relationship between living things as illustrated by food webs. But, in order to manufacture food, a plant needs sunlight, water and carbon dioxide. Also, dead organisms have abiotic components within their bodies that return to the ecosystem via the process of decomposition. Therefore, there is a definite relationship between the biotic and abiotic components of an ecosystem.