Managing the Biosphere
Stephen R. Carpenter
Human attempts to manage nature are at least as old as agriculture and possibly much older. By the time ecology was formalized as a science, applications and basic ecology were both on the agenda. Stephen Alfred Forbes (1844–1930), an influential American ecologist whose career spanned the origins and consolidation of ecology as a science, demonstrated the mix of practical and curiosity-driven science characteristic of the discipline. Forbes began his career as an economic entomologist, solving problems of pollination and pests that presage work on biological control reviewed by Murdoch in this volume (chapter VII.1). Then Forbes undertook studies of massive fish mortality in Lake Mendota, Wisconsin. He showed the connection of algae blooms and lake physics to fish kills and embarked on a remarkable research program into the ecology of lakes and rivers. His most famous paper, “the lake as a microcosm” (1887), foreshadowed the ecosystem concept as well as modern ideas of behavioral ecology and food web dynamics. As president of the Ecological Society of America and a member of the National Academy of Sciences, Forbes championed the practical uses of basic ecological science for the betterment of humankind. Many other pioneering ecologists pursued research on practical problems of society along with fundamental science questions. Basic and applied ecology have always been intertwined.
From these beginnings, ecology for management has evolved in several dimensions. There has been a progression from single-species problems, such as management of a single resource population or a single pest, to problems of managing ecosystems and social– ecological systems. This does not mean that the singlespecies problems are no longer relevant—in some cases elegant solutions were found, and in other cases severe problems remain. Instead, the expansion of scope is a natural response to the discovery that larger contexts— ecological or social or both—must be addressed to make progress on pressing environmental problems.
Ecological management problems often begin with suppression of a single pest species or harvest of a single wild species of fish or game and progress to consideration of the ecosystem in which the focal species is embedded. Murdoch (chapter VII.1) shows how biological control of insect pests has expanded in scope to consider dynamics of interacting resource and consumer populations. Hilborn (chapter VII.2) describes how fisheries management coalesced around the idea of maximum sustainable yield (MSY) of a single-species stock. Obvious shortcomings of MSY have led to an ecosystem management perspective considering dynamics of multiple interacting factors and the physical– chemical environment, posing a much more difficult management problem. Boyce, Merrill, and Sinclair (Chapter VII.3) point to a similar expansion of scope in wildlife management. In particular, they note the challenges posed by multiple states of wildlife populations and the ecosystem feedbacks that control them. Management of disease is a relatively new and expanding area of ecosystem management that links wildlife, ecosystem dynamics, and human health. Patz and Olson (Chapter VII.6) explain how changes in biodiversity and land use cascade through ecosystems to affect transmission, resurgence, or emergence of diseases that affect ecosystems and people.
Although management of living resources often began with a single-species perspective and then expanded in scope to consider the ecosystem, management problems of water or nutrients start with an ecosystem perspective. The scientific roots of these management perspectives lie in the geosciences, especially hydrology and geochemistry, rather than in ecology. Nonetheless, research on water and nutrients has long been a part of ecology, and the boundaries between ecology and the geosciences are not as sharp as they once were. Fresh water is frequently a limiting and nonsubstitutable resource for ecosystems and people, so ecosystem management at local, continental, or global scales often centers on water. Alcamo (chapter VII.4) summarizes the challenges of managing freshwater supply. Problems of water quality often go hand in hand with those of water quantity.