Managing for ocean biodiversity to sustain.pdfVIP

204 ? The Ecological Society of America Compelling evidence is accumulating from terrestrial,freshwater, and marine systems to suggest that sus- tainable ecosystem services depend upon a diverse biota (Daily et al. 1997; Loreau et al. 2001; Tilman et al. 2001; Wall et al. 2004; MA 2005; Sala and Knowlton 2006; Worm et al. 2006; Butler et al. 2007; Hector and Bagchi 2007). In principle, such knowledge should be useful in guiding a national ocean policy that maintains the ser- vices provided by oceans into the future. But does know- ing the link between diversity and services usefully inform policy? We argue that management to sustain biodiversity could provide a critical foundation for a practical, ecosys- tem-based management (EBM) approach to the oceans. Globally, 60% of ecosystem services are degraded (MA 2005). These ecosystems provide food, shelter, recycling, and other support mechanisms that human communities require, but fundamental services are declining as ecosys- tems are unraveled by human impacts (Palmer et al. 2004). Marine ecosystems (Figure 1) provide a constellation of services: they produce food, receive and assimilate wastes, protect shorelines from storms, regulate the climate and atmosphere, generate tourism income, and provide recre- ational opportunities (Covich et al. 2004; MA 2005). The extraordinary diversity of the world’s oceans – across the different levels of ecosystems, habitats, species, functional roles, and genetic diversity (Carpenter et al. 2006; Sala and Knowlton 2006) – and the interconnections of marine, coastal, freshwater, and terrestrial ecosystems make manag- ing ocean ecosystems crucial for long-term prosperity. Although degradation of ecosystems might be reversed through appropriate policies (MA 2005), there are sub- stantial information gaps in our understanding of ecosys- tem processes (Carpenter et al. 2006), which impede prac- tical ideas about implementing policy. EBM involves incorporating knowledge of ecosystem pro