Energy Flow and Circulation of Matter
Matter flows through the ecosystem in the form of the non-living nutrients essential to living organisms
| Energy Flow | Circulation of Matter |
| Addition. Energy is being continuously passed from sun to the ecosystem. | No material is added from outside. |
| Movement. Energy flow is unidirectional. There is no circulation. | Materials circulate repeatedly between biotic and abiotic components. |
| Loss. Energy is dissipated at every level of its transfer and transformation. | There is no loss of matter. |
| Pool. An energy pool does not exist on earth. | Nutrient pool occurs in the abiotic environment. |