The Bioaccumulation of Mercury in Aquatic Organisms from Two Similar Lakes with Differing pH

摘要: Two small drainage lakes of similar surface area (0.4–0.6 km 2 ) and depth, situated in close proximity to one another (about 9 km apart) the Muskoka-Haliburton district rural Ontario, Canada were chosen investigate effects differing pH on Hg accumulation fish other biota. Blue Chalk Lake is circumneutral (pH = 6.3–6.9) with an average dissolved organic carbon (DOC) concentration 2.69 mg/L; Plastic acidic 5.2–5.6) a DOC level (2.72 mg/L). Neither lake impoundment, neither receives inputs from point-source urban or industrial waste emissions. Surficial (top 4 cm) sediments various aquatic biota, including crayfish (Orconectes virilis)], 5 species [brown bullhead (Ictalurus nebulosus), creek chub (Semotilus atromaculatus), pumpkinseed sunfish (Lepomis gibbosus), yellow perch (Perca flavenscens) rock bass (Ambloplites rupestris)] sampled for analysis. Only occurred both lakes. Significant size (length) vs. Hg-concentration relationships observed brown bullhead, pumpkinseed, bass, but not nor either lake. Rock had highest mean (1.02 ± 0.98 μg/g dry wt.). Pumpkinseed overall rate increasing size. Several individual concentrations equal greater than levels reported be hazardous breeding piscivorous birds, such as common loons (Gavia immer), whereas no approached this threshold (0.3 wet wt). This study illustrates importance within-lake parameters, particularly pH, trophic level, determining that receive atmospheric inputs.