EFFECTS OF PINNA CLAMS ON BENTHIC MACROFAUNA AND THE POSSIBLE IMPLICATIONS OF THEIR REMOVAL FROM SEAGRASS ECOSYSTEMS

摘要

Seagrasses are widely distributed throughout the world's oceans and are among the most productive and economically important of all ‘ecosystem engineers’. They provide habitat structure to coastlines that would otherwise consist of bare sand, and deliver many important ecosystem services, such as shoreline stabilization (Bos et al., 2007), nutrient cycling (worth US$19,000 ha?1year?1; Costanza et al., 1997), habitat provision (for fish, bird and invertebrate species; Heck, Hays & Orth, 2003; Hughes et al., 2009) and carbon sequestration (Macreadie et al., 2013; McLeod et al., 2011). Within seagrass ecosystems, there are also other organisms that provide different habitat structure, but there have been few empirical tests of whether these additional habitat-providing organisms are effectively redundant because of the habitat provided by the seagrass, or whether they provide unique and ecologically-significant ecosystem services not offered by seagrasses.