http://www.uen.org/themepark/cycles/nature.shtml Nature’s cycles have to do with how the earth renews itself. The living things within an ecosystem interact with each other and also with their non-living environment to form…
http://en.wikibooks.org/wiki/Ecology/Biogeochemical_cycles Planet earth from space In the previous chapter on environmental response, we considered the various ways that individual organisms respond to the physical, chemical, and/or biological stimuli in their environment.…
http://www.geography4kids.com/files/cycles_energy.html Energy does not cycle the way nutrients and atoms do. Energy enters the ecosystem from the Sun and exits after the organisms have taken as much as they need. Organisms release…