This single greatest cause of species extinction is human activity. The purpose of this paper is not to resolve these issues but to assess briefly some of the scientific challenges we face as we attempt to establish priorities in biodiversity conservation, and to propose a general strategy for...

In the case emission of non-uniformly dispersed pollutants such as SO2 the negative effects depend on the location of the sources. A unit increase at one source must be compensated by either a lareg or smaller reduction at another source to keep the negative effects at the same level. Such trade...

This paper extends and challenges Maler and de Zeeuw's (1996) acid rain linear-quadratic differential game.