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Table of ContentsExecutive Summary .................................................................................................................... 2Table of Contents ....................................................................................................................... 3Introduction ............................................................................................................................... 4Methods ..................................................................................................................................... 5Study region ........................................................................................................................... 5Ecological surveys .................................................................................................................. 9Reef fish composition ........................................................................................................ 9Benthic substrate composition ........................................................................................ 10Statistical analyses ............................................................................................................... 10Socio-economic surveys ....................................................................................................... 10Results ...................................................................................................................................... 11Coral Ba/Ca .......................................................................................................................... 11Fish biomass, abundance and species richness ................................................................... 11Variation in benthic structure .............................................................................................. 12Socioeconomic survey results .............................................................................................. 14Discussion................................................................................................................................. 16Conclusions and Recommendations ........................................................................................ 18Acknowledgments.................................................................................................................... 20References ............................................................................................................................... 21Page | 3
IntroductionHuman activity on land has increased global sediment loss by an order of magnitude overnatural weathering rates due to human population growth driving land clearing foragriculture and development (Pimentel et al. 1993; Wilkinson 2005). Urbanization andmining have also contributed to localised increases in sedimentation to the nearshore(Fallon et al. 2002). While sediment supply and turbidity are limiting factors in coral reefdevelopment (Hopley 1995; Smithers et al. 2006), nearshore reefs are adapted to oftenhighly turbid conditions and, when distant from human disturbance, can be highly diverse(Veron 1995; Mallela et al. 2004; Fabricius et al. 2005). However, nearshore reefs adjacentto highly modified catchments or those with large point-sources of terrestrial pollution maybe particularly vulnerable to ecological shifts if chronically degraded water quality reducesresilience to disturbance (McCook 1999). If these disturbances take place within theboundaries of marine protected areas (MPAs), the accompanying loss of resilience maygreatly affect the ability of management to yield fisheries benefits and biodiversityconservation.Field studies from recent decades suggest that coral assemblages from sites withinproximity to land based pollution are shifting in response to both point (Smith et al. 1981)and non-point sources (Lapointe 1997; van Woesik et al. 1999). Along natural andanthropogenically enhanced water quality gradients, scleractinian corals living closest toterrestrial and fluvial sources are generally characterized by: (1) high rates of partialmortality; (2) low rates of recruitment; (3) reduced skeletal density; (4) decreased tissuethickness; and (5) reduced depth distributions (Kleypas 1996; Barnes and Lough 1999;Nugues and Roberts 2003; Fabricius 2005). These changes in coral communities are oftenassociated with: increased algal cover (Fabricius et al. 2005); increased abundance and ratesof bioerosion by macroborers (Tribollet and Golubic 2005); and reduced octocoralabundance and diversity, particularly from zoothanthellate clades (Fabricius and McCorry2006). There has also been evidence of reduced fish diversity and biomass related topredictors of terrestrial runoff (e.g. distance from land, visibility, % of mud in sediments),though some fish species, such as Pleotropomus leopardus, Scarus ghobban, and Siganuslineatus may be naturally more closely associated with coastal reefs (Letourner et al. 1998).In the absence of long-term water quality monitoring data to assess changes to sedimentdelivery over time, the ratios of certain trace elements to calcium (Ca) within long-livedcoral skeletons are good natural tracers of fluvial or pollutant inputs to seawater. Barium(Ba) is one such tracer as ~50-75% of the total dissolved Ba load in nearshore waters issourced from river discharge (Hanor and Chan 1977; Carroll et al. 1993). Ba is attached tofine-grained clay particles in river runoff but desorbs in low salinity estuarine regions (Coffeyet al. 1997). The dissolved Ba moves offshore within the flood plume where it becomesincorporated into coral skeletons in close proportion to its local abundance (Livingston andThompson 1971; McCulloch et al. 2003). The position of a reef across the continental shelf,its relative proximity to highly modified terrestrial catchments and the tidal range will affectexposure to terrestrial discharge and therefore the recurrence interval of major disturbance.Long-term records of coral Ba/Ca concentrations can be used to identify historic periods ofterrestrial disturbance which may have influenced present-day ecological conditions onnearshore reefs (Jupiter et al. 2008).Page | 4
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Page 3: Executive SummaryResearch for this
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Page 17 and 18: DiscussionCurrent day coral reef co
Page 19 and 20: able to recover quickly is likely d
Page 21 and 22: the boundaries of Nasue MPA further
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Page 25: Veron JEN (1995) Corals in Space an

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