Ecology: Concepts and Applications 4th Edition by Manual Molles

تمرين 1

Of all the naturally occurring elements in the biosphere, why have the cycles of carbon, nitrogen, and phosphorus been so intensively studied by ecologists? (Hint: Think about the kinds of organic molecules of which these elements are constituents. Also think back to our discussions, in chapter 18, of the influences of nitrogen and phosphorus on rates of primary production.)