Abstract

The “land community” (or “biotic community”) that features centrally in Aldo Leopold’s Land Ethic has typically been equated with the concept of “ecosystem.” Moreover, some have challenged this central Leopoldean concept given the multitude of meanings of the term “ecosystem” and the changes the term has undergone since Leopold’s time (see, e.g., Shrader-Frechette 1996). Even one of Leopold’s primary defenders, J. Baird Callicott, asserts that there are difficulties in identifying the boundaries of ecosystems and suggests that we recognize that their boundaries are determined by scientific questions ecologists pose (Callicott 2013). I argue that we need to rethink Leopold’s concept of land community in the following ways. First, we should recognize that Leopold’s views are not identical to those of his contemporaries (e.g., Clements, Elton), although they resemble those of some subsequent ecologists, including some of our contemporaries (e.g., O’Neill 2001, Post et al. 2007, Hastings and Gross 2012). Second, the land community concept does not map cleanly onto the concept of “ecosystem”; it also incorporates elements of the “community” concept in community ecology by emphasizing the interactions between organisms and not just the matter/energy flow of the ecosystem concept. Third, the boundary question can be illuminated by considering some of the recent literature on the nature of biological individuals (in particular, Odenbaugh 2007; Hamilton, Smith, and Haber 2009; Millstein 2009), focusing on concentrations of causal relations as determinative of the boundaries of the land community qua individual. There are challenges to be worked out, particularly when the interactions of community members do not map cleanly onto matter/energy flows, but I argue that these challenges can be resolved. The result is a defensible land community concept that is ontologically robust enough to be a locus of moral obligation while being consistent with contemporary ecological theory and practice.