Linking Science and Technology to Society's Environmental Goals (1996) / Chapter Skim
Currently Skimming:
Status of Ecological Knowledge Related to Policy Decision-Making Needs in the Area of
Status of Ecological Knowledge Related to Policy Decision-Making Needs in the Area of
Pages 327-344
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 328... ...
While we might set a goal of minimizing human intervention in certain systems, our current knowledge of ecology suggests that we should not set a goal of maintaining a system in a "natural state." Second, ecological knowledge undergirds our ability to predict the ecological -- and economic and social -- consequences of human impacts, such as filling a wetland, changing stream flows, or introducing chemicals into the environment. Until recently, virtually all environmental management has been reactive rather
|
From page 329... ...
Third, ecological knowledge helps to define the types of policy tools and resource management practices that can be used to achieve various social and ecological objectives. For example, between the 1950s and 1970s, fisheries management relied on deterministic fisheries population models that were used to calculate harvest levels based on the maximum sustained yield of the population.
|
From page 330... ...
Similarly, requirements to maintain buffer strips along stream and river corridors help protect streams from sedimentation and changes in temperature and water flow. More generally, however, we have established relatively few goals related to the protection of ecosystem services.
|
From page 331... ...
Concepts like "maximum sustained yield" and "optimum sustained yield" became the guiding principles of resource management. Clearly, though, no single harvested species exists in isolation from other species in the community, and virtually all ecosystems provide far more products and services than just the few harvested species.
|
From page 332... ...
Moreover, laboratory studies can often be used to identify particularly threatening chemicals relatively quickly and cheaply. More worrisome, however, are chemicals that do not exhibit direct toxic effects on plants and animals but may have chronic effects.
|
From page 333... ...
Because species with restricted ranges are sometimes clustered in "hot spots" of diversity, protection of those hot spots could greatly reduce the effect of habitat loss on species diversity. For a given species for which detailed demographic and life history information is available, we are able to make projections of the probability of survival of the species when its habitat is lost by use of Minimum Viable Population methodologies (Shaffer 1981)
|
From page 334... ...
1981. "Minimum Population Sizes for Species Conservation." BioScience 31.
|
From page 335... ...
species that have large numbers of offspring, rapid growth, and high dispersal abilities, are more likely to become established in new habitats than "K"-selected species with lower population growth rates. While the removal of a keystone species will, by definition, have profound impacts on a community and the services it provides, the removal or addition of some species in communities appears to have little demonstrable effect either on other species or on an ecosystem process.
|
From page 336... ...
While the increased frequency of El Niño in recent years cannot be conclusively tied to human-caused changes in climate, the example demonstrates how ocean current changes that are likely to occur in the event of global warming could have substantial effects on human health. Current models of changes in the distribution of disease vectors under likely future climates suggest that developing countries will see an increase in malaria, schistosomiasis, sleeping sickness, dengue, and yellow fever.
|
From page 337... ...
But, by and large, unless a particular system has been the subject of intense research and monitoring, the current status of ecological knowledge only enables us to identify a list of potential consequences of a given action and to identify the set of data or experiments that would enable that uncertainty to be reduced. MANAGING RESOURCES Ecological knowledge helps to define the types of management practices and policy tools available for resource management.
|
From page 338... ...
WHERE CAN IMPROVED ECOLOGICAL KNOWLEDGE BEST AID DECISION-MAKING? Setting Goals The greatest need for improved ecological knowledge currently relates to its role in setting environmental goals.
|
From page 339... ...
For example, we sought to prevent endangered species from going extinct, but paid less attention to the need to prevent species from becoming endangered. It is fashionable now to speak of ecosystem management as the new environmental management paradigm.
|
From page 340... ...
Similarly, in the Pacific Northwest, the amenity value of relatively undisturbed ecosystems has a high economic value, demonstrated by the rapid growth in "footloose" industries in the Northwest. A more accurate calculus of the economic costs and benefits of resource conservation in the Northwest would probably give greater weight to the goal of biodiversity conservation.
|
From page 341... ...
Second, and much less conclusive, the effect of a perturbation can be compared to the long-term behavior of the system. While experimental ecology will continue to provide the primary means of teasing apart the workings of ecological systems, we must turn to long-term monitoring as the only practical means of identifying unexpected impacts and enabling adaptive management in situations where the replication of an experiment is impossible.
|
From page 342... ...
8. What environmental indicators can be developed that bear on the achievement of environmental management goals?
|
From page 343... ...
Ecological knowledge can help improve our management decisions. But because we still undervalue ecological systems as resources, we also undervalue the need for the inventory, monitoring, and research that will enable us to anticipate and prevent their loss and degradation.
|
From page 344... ...
1981. Minimum population sizes for species conservation.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.