Natural Landscapes, Natural Communities, and Natural Ecosystems

Human Intervention, Disturbance, and Defining "Natural" More than a century ago, Ralph Waldo Emerson, in his essay on "The Uses of Natural History," argued that "[right action] is conformity to the laws of nature."! Many ecologists, environmentalists, and policymakers since then have urged conformity to these "laws of nature." They have defined "natural ecosystems," as opposed to "artificial ecosystems," and established biocentric principles for how humans should treat these "natural ecosystems."? Indeed, natural history and much of ecology presuppose some concept of natural place.' Likewise biogeography presupposes that the earth has "natural divisions," and island biogeography, the developmental basis for landscape ecology, arose from a series of "natural experiments.?' Because direct experimental manipulation of all relevant variables is rarely possible, landscape or regional ecology continues to progress by relying on quasi-experiments in the "natural laboratories" of various regions.' An important goal of many discussions about "natural history," "natural ecosystems," "natural places," "natural divisions," "natural experiments," and "natural laboratories" is not only to learn more about these "natural" phenomena but also, as one ecologist put it, to "protect natural systems."! A fundamental argument is that people ought to "respect nature" because the structures and functions of the natural world themselves have provided a guide for conservation and preservation decisions.' Indeed, if ecology and environmental policy-making are to avoid being arbitrary, terms such as "ecosystem" and "community" do not name mere concepts or human constructs but instead describe real characteristics of the natural world. The goal of protecting natural ecosystems or communities, however, often fails to provide direction for environmental policy because ecologists cannot always specifyeither what is "natural" or when human actions are in accord with nature.