This paper presents a study of use of the rhetorical figure of antithesis and other contrastive relations in several modern-day environmental science policy journal articles on issues of food security, climate change, and water resource management. The articles present the conflicting perspectives of environmentalists and engineers, i.e., the view that nature should be preserved and protected versus the view that it should be engineered to solve human problems. The main contribution of this paper is a taxonomy characterizing argumentative uses of (...) contrastive relations in these articles based on our semantic/pragmatic interpretation of text including, in some cases, discourse coherence relations. The number of examples and the breadth of the taxonomy is indicative of the key role of contrastive relations in argumentation in this genre. This investigation is a necessary step towards comprehensive computational approaches to detecting antithesis and other contrastive relations and to identifying their argumentative roles. (shrink)