Shocking News Just In: People are Part of Natural Systems!
In a rare instance of navel-gazing, there is some new research that shows more than 2/3 of ecology studies are focused on "protected" areas where human influence is minimized.
Very few studies are conducted in systems where humans behavior has a large influence. If you think that ecology is about studying nature as "separate" from humans, then it makes sense to choose study sites where natural processes are operating without human "interference". Although this is pretty much a myth because at this point in global development it is hard to say that any protected areas don't have at least some human influence. Regardless, the more consistent philosophical standpoint is to recognize that humans are part of nature and therefore human-natural systems need to be studied. Furthemore, the ecosystem services (such as food and water!) provided by human-natural systems are critical for the survival of our species and civilizations.
This of course means that the definition of ecology should include social science because you need to understand how human behavior interacts with ecosystems. This requires interdisciplinary teams, and grant programs like NSF's Biocomplexity and Coupled Human-Natural Systems (http://www.nsf.gov/funding/pgm_summ.jsp?pims_id=13681)
do thankfully recognize this necessity. Now it just needs to be recognized by the rank-and-file of ecological scientists who don't understand that social science can be just as rigorous as collecting data about the population dynamics of some species or other natural scientific enterprise.