If it was a real issue, then it would perfectly reasonable to investigate and to develop human modification to respond. (climate-resistance.org)
Our next global challenge is likely to be human modification of the global nitrogen cycle. (dotearth.blogs.nytimes.com)
The excitement in this enterprise is discovering useful patterns; the danger is that we can create them to suit our own intellectual needs, as in the sum total of all purposeful human modifications of the landscape. (blisssmag.com)