AQUACULTURE EFFECTS ON SOME PHYSICAL AND CHEMICAL PROPERTIES OF THE WATER COLUMN: A META-ANALYSIS

More than 30 peer-reviewed articles (1980–2005) were analysed using meta-analytical reviewing techniques, and about 340 study cases were used to test whether aquaculture facilities had any effects on physical and chemical variables. The analysis tested differences between experimental conditions vs. chosen-by-author controls. Across all study cases, cultivated organisms (fish, shrimps and bivalves) did not have any clear effects on the water temperature and salinity. Dissolved oxygen also was found to be unaffected by aquaculture practices. On the other hand, crowding led to significant pH variations, which was more accentuated in shrimp (d+ = 0.66;P <0.05) than in fish farming plants (d+ = −0.15;P >0.05).Water transparency and turbidity were significantly affected by shrimps and fish farming.