Explanation : Ecosystems contain essentially two kinds of commodities: matter (nutrients) and energy. Material nutrients cycle through the biotic and abiotic parts of the ecosystem, available for repeated use by the organisms in the ecosystem’s community. However, energy enters an ecosystem by being used to convert low-energy carbon dioxide into high-energy carbohydrate, then passes through one or more of the organisms of the community, and is then lost to the ecosystem. Eventually, all of the energy that enters the ecosystem is lost in the form of heat. ....Read more