Ecosystem"
refers to the set of ecological communities in a particular region and the physical
and chemical processes that link them. For example, in addition to all the organisms found in a tidal marsh (the plants providing structure, the primary productivity from planktonic algae, and the various animals and microbes rounding out the food web and community), this marsh ecosystem includes factors such as the cycling of nutrients and other chemicals within the local community, as well as their movement between the marsh and neighboring upstream and downstream communities.
Examples of different ecosystems are pictured at the bottom of this page.
Primary Productivity
Photosynthetic "primary productivity" refers to the amount of new plant growth (both micro- and macroscopic) each year ? made possible by plants' ability to convert sunlight into chemical energy.
Apart from other relatively small sources of chemical energy in various ecosystems (such as certain minerals in geothermal pools and deep-sea vents), this plant productivity is the basis for all other life on Earth.
| This satellite
image depicts primary productivity in the Pacific ocean.
Red areas represent high concentrations of chlorophyll, and purple areas are low concentrations. These images are from the SeaWiFS project and an educational page on "Ocean Color from Space" it is produced by NASA.
Ecosystem Examples
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