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systems. In addition, marine ecosystems provide hard-to-quantify off-site benefits as components of regional and global climatological, biological, and chemical systems, including removal of carbon dioxide from the atmosphere, production of oxygen, moderation of coastal temperatures, and powering terrestrial hydrologic cycles (Daily et al., 1997). This chapter describes these different types of values, the potential costs and benefits of MPAs in supporting these values, methods for evaluating societal values, and finally the need for community involvement in the decisionmaking process.

ORIGIN OF THE VALUES ASSOCIATED WITH MARINE ECOSYSTEMS

The “natural” functioning of marine ecosystems has included human influences for significant periods of time (Zacharias et al., 1998). In North America, coastal areas have been affected by human activities starting with the migration of people across the Bering Sea land bridge and colonization of the West Coast more than 10,000 years ago. When Europeans arrived in the Americas, they encountered marine ecosystems already shaped by human influence. Human exploitation of marine resources changes the structure of ecosystems through impacts on the food web and habitat. Yet access to and use of the sea also affect the structure of human societies and the evolution of their perceptions of the values provided by marine systems.

Because humans are so efficient in capturing fish and other marine species, the human role in the ecosystem may be considered analogous to that of a key-stone predator (Castilla, 1993). The impacts on the structure of coastal marine communities can be direct, indirect, or subtle and are revealed when humans are excluded from the ecosystem, for example, after establishing an ecological reserve. However, human impacts are mediated by influences other than typical predator-prey interactions that reflect unique human social characteristics such as cultural traditions, economic conditions, and technological advances. Cultural traditions can be characterized in terms of environmental ethics and cultural landscapes as described below.

Environmental Ethics

Biocentric values—valuing nature for its own sake—are important for many people as a function of their beliefs about the proper relationships between humans and nature. These beliefs are critical for explaining the adaptations of human cultures to their local, regional, and world environments. A key question in characterizing environmental ethics is whether or not humans are perceived as a part of nature or separate from nature (McDonnell and Pickett, 1993).

Increasingly, people in many nations value the quality of the environment and recognize that animals and plants have the right to some measure of protec-



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