Solutions for sustainable mariculture - Convention on Biological ...

<strong>Solutions</strong> <strong>for</strong> <strong>sustainable</strong> <strong>mariculture</strong> - avoiding the adverse effects of <strong>mariculture</strong> on biological diversityANNEX IIDESCRIPTION OF IMPACTS, EFFECTS, MITIGATION TOOLS AND RESULTSProblemImpactMain mitigation tool,enhancement ofbeneficial effectAssociatedmitigation toolResults of mitigation1) Excess nutrientaddition by fin fish andshrimp <strong>mariculture</strong>(or other carnivorousorganisms) to the watercolumn and sedimentsPotential eutrophicationwith biodiversity lossesa) Best site selection(including optimalflushing and dispersal ofnutrientsa.1. Offer of alternativefisheries resources.a.1.Decrease of local nutrientinputs, lesser effectseven positive effects onlocal biodiversity andecosystem processes byreleasing harvesting pressureover wild stocks atlocal scalea.2.Integrated aquaculture.Culturing different speciestogether (eg. Salmon w/mussels, or salmon w/macroalgae)Increased habitat structure,more efficient use of nutrients,increased nutrientfluxes, lesser effects or positiveeffects on biodiversitya.3. Coupling w/artificialreefs, sport fishing, localfisheriesIncreased habitat structure,more efficient use of nutrients,increased nutrientfluxes, lesser effects or positiveeffects on biodiversityb) Better maanagement,decrease conversion ratios(improved specializedtraining and education)b.1-fin-fishb.2. shrimpDecreased nutrient inputsto environment, lessereffects or even positiveeffects on biodiversity andecosystem processesc) Changes in nutrition,low P, N dietsDecreased nutrient inputsto environment, lessereffects on biodiversity andecosystem processesd) Reducing stockingdensitye) Use of enclosed, orre-circulating systems(both <strong>for</strong> finfish andshrimp culture)Decreased nutrient inputsto environment, lessereffects on biodiversity andecosystem processes2) nutrients in outflowfrom enclosed systems,tank or pond <strong>mariculture</strong>(finfish/shrimp)mpactRemoval of sludge fromfish/shrimp pond watersand treatment of effluents,use of biofilters and externalsettling tanksDecreased nutrient inputsto environment, lessereffects on biodiversity andecosystem processes42