00000nam 2200000za 4500 9.557278 CaOODSP 20221107133915 cr ||||||||||| 150406s2015 oncdb ob f000 0 eng d 978-1-100-25590-3 CaOODSP eng eng fre n-cn--- Fs97-4/3056E-PDF Benthic macroinvertebrates and sediment characteristics of Hamilton Harbour in 1984, and changes between 1964 and 1984 [electronic resource] / by Cam Portt ... [et al.]. Macroinvertébrés benthiques et caractéristiques des sédiments dans le port de Hamilton en 1984, et changements entre 1964 et 1984 Burlington, Ontario : Fisheries and Oceans Canada, 2015. vi, 46 p. : graphs, maps Canadian manuscript report of fisheries and aquatic sciences, 1488-5387 ; 3056 Includes bibliographical references (p. 16-18). A survey of the benthic macroinvertebrates and sediment chemistry in Hamilton Harbour was conducted in 1984. Results were compared to a 1964 survey done at the same sites, prior to extensive efforts to reduce the nutrient and contaminant loadings to the harbour. A large toxic zone, devoid of all macroinvertebrates, in 1964 had shrunk to one site in 1984. Concentrations of metals especially Fe and Zn, and PAH levels remained high in the sediments. Invertebrate density had increased throughout the harbour between 1964 and 1984. Average oligochaete density increased by an order of magnitude from 5000 m-2 in 1964 to over 45,600 in 1984. The proportion of pollution tolerant worm species decreased. Although Sphaeriidae clams and several chironomid genera had appeared in the harbour by 1984, few other benthic taxa were present. Low oxygen levels in the deepest areas and the elevated sediment contaminants continued to restrict the composition of the benthic fauna. Issued also in printed form. Text in English, abstract in English and French. gccst Molluscs gccst Aquatic animals gccst Contaminated sites Portt, Cameron Bruce. Canada. Department of Fisheries and Oceans. Benthic macroinvertebrates and sediment characteristics of Hamilton Harbour in 1984, and changes between 1964 and 1984 / (CaOODSP)9.515995 Canadian manuscript report of fisheries and aquatic sciences, 1488-5387 ; 3056. (CaOODSP)9.505211 PDF 718 KB https://publications.gc.ca/collections/collection_2015/mpo-dfo/Fs97-4-3056-eng.pdf