Estuarine ecosystems are among the most productive ecosystems on the planet. Marine habitats are valued at providing an estimated $14 trillion worth of ecosystem goods and services annually, or 43% of the global total (Costanza et al. 1997). Scientific evidence in the face of anthropogenic global change is showing many of these marine ecosystems are threatened (IPCC 2001).
Sustainability includes the valued habitats, resources, and ecosystem services provided. It is important to look at freshwater management in terms of sustainability at these levels to determine what resources can be protected, the important habitats for their survival, and the economic importance of those resources.
Economists work with scientists to study how humans apportion natural resources based on their wants by valuing natural resources and processes. Ecosystem services are any resource or organisms that occur in a natural state and/or organism’s life processes that can be used for monetary gain; this includes freshwater. Economists and scientists can work together to provide tools that address the issues of balancing growth with conservation of natural resources.