(Continued from part 1)
5) The word that the writer picked may be something close to "private language" - something known in a close circle of friends, or a small specialized segment of the population and the writer is aware that this population does not intersect at all with the intended readership.
In this case, however, it's easier - there is a semicolon, and the flow of the sentence shows us that what follows the semicolon is the definition of the word "patchiness" as intended by the writer. "an environment that varies from place to place". However, interpretation of the overall sentence reveals a contradiction, which is puzzling:
A. Ecologists think that stability comes from "patchiness", not from diversity
B. An environment has "patchiness" when it varies from place to place. An environment that has patchiness is not uniform.
(Continued in part 3)