The ecological, economic, and social importance of the oceans

The oceans have long been recognized as one of humanity's most important na tural resources. Their vastness has made them appear to be limitless source s of food, transportation, recreation, and awe. The difficulty of fencing a nd policing them has left them largely as open access resources to be explo ited by anyone with the means. However, in recent times we have begun to re ach the limits of the oceans and must now begin to utilize and govern them in a more sustainable way. This paper summarizes emerging information on th e interrelated ecological, economic, and social importance of the oceans, a nd on developing institutions for their sustainable governance. In addition to their traditional importance as sources of primary and secondary produc tion, and biodiversiy, the importance of the oceans in global material and energy cycles is now beginning to be better appreciated. Integrated models of the global ocean-atmosphere-terrestrial biosphere system reveal the crit ical role of the oceans in atmospheric gas and climate regulation, and for water, nutrient, and waste cycling. Recent estimates of the economic value of the marketed and non-marketed ecosystem services of the oceans indicate a huge contribution to human welfare from the functions mentioned above plu s raw materials, recreational, and cultural services. The oceans have been estimated to contribute a total of similar to 21 trillion US$/year to human welfare (compared with a global GNP of similar to 25 trillion US$), with s imilar to 60% of this from coastal and shelf systems and the other 40% from the open ocean. and with the oceans contributing similar to 60% of the tot al economic value of the biosphere (Costanza et al., 1997. The value of the world's ecosystem services and natural capital. Nature 387, 253-260). The social importance of the oceans for global transportation and as a unifying element in the cultures of many coastal countries cannot be overestimated. However, the cultural traditions of open access must be replaced with more appropriate property rights regimes and governance structures. Some altern ative sustainable governance ideas are briefly discussed, emphasizing the n eed for an expanded deliberative process to develop a shared vision of a su stainable use of oceans. (C) 1999 Elsevier Science B.V. All rights reserved .