Lakes and Watercourses
Lakes and Watercourses Lakes and Watercourses
Assessment of mercury in fish should be based on analysis of pike weighing 0.4 – 1.6 kg. In lakes with a surface area of up to 10 km 2 , at least five fish should be used; in larger lakes, at least ten fish. Concentrations in sediment (present concentrations) refer to the level 0 – 1 cm on accumulation bottoms (loss of ignition >10%, ds < 25%). Metals in aquatic moss refer to concentrations in annual growth. Moss growing locally as well as planted specimens can be used. Exposure should have lasted for at least three weeks in the latter case. Where possible, it is recommended that local background concentrations recorded upstream or in a nearby aquatic area be used to determine present regional background concentrations. This applies particularly to aquatic moss, about which little is known in relation to regional background concentrations. Natural concentrations in sediment should primarily be determined using local values obtained from deeper strata of sediment, which reflect pristine concentrations in the area. In the case of most metals, these concentrations are found in sediments some 15 – 30 cm deep. But in eutrophied waters (where sedimentation occurs rapidly), the 150-yearold sediment will be found much deeper down. Much older sedimentary strata must be analysed for lead, since the environmental load of this metal has been accumulating for much longer. When analysing sediment, it is very important that the quantity of organic matter measured as loss on ignition is approximately as great in the sediment to be compared. This is particularly important with Pb and Hg, since the concentration of these metals in particular is correlated to the concentration of organic matter in the sediment. References Alm, G., Bengtson, M., Borg, H., Göthberg, A., Johansson, K., Lindeström, L. & Lithner, G. (1998): Metaller (”Metals”). From: T. Wiederholm (Ed.). Bedömningsgrunder för miljökvalitet – Sjöar och vattendrag. Bakgrundsrapport 1 – Kemiska och fysikaliska parametrar (”Environmental Quality Criteria – Lakes and Watercourses. Background report 1 – Chemical and physical parameters”). Swedish EPA Report 4920. Canadian Council of Resource and Environmental Ministers (CCME) (1987): Canadian water quality guidelines. Ottawa, (updated in April 1991 and May 1996). Lithner, G. (1989): Bedömningsgrunder för sjöar och vattendrag. Bakgrundsrapport 2 – metaller (”Quality criteria for lakes and watercourses. Background report 2 – Metals”). Swedish EPA Report 3628. National Food Administration (1992): Statens livsmedelsverk kungörelse med allmänna råd om konsumtion av fisk (”National Food Administration Regulations on Consumption of Fish”), SLU FS 1991:25. – Vår Föda 44(4):173 – 177. 49
Swedish EPA (1993): Metals and the Environment – Status and Trends, Swedish EPA Report 4245. Norwegian EPA (1997): Klassifisering av miljøkvalitet i ferskvann. – Veiledning (”Classification of freshwater quality - Guidelines”) 97:04. 50
- Page 1 and 2: Environmental Quality Criteria - La
- Page 3 and 4: TO ORDER Swedish Environmental Prot
- Page 5 and 6: Reference Group Mats Bengtsson, Swe
- Page 7 and 8: Summary This report on lakes and wa
- Page 11 and 12: included. In addition to a large nu
- Page 13 and 14: ased estimates are used. Given that
- Page 15 and 16: TABLE 1. SUMMARY of parameters incl
- Page 17 and 18: 16 The current conditions scale in
- Page 19 and 20: (in Swedish with English summary).
- Page 21 and 22: conditions for watercourse flora an
- Page 23 and 24: show the availability of nitrogen i
- Page 25 and 26: Mean concentration of total phospho
- Page 27 and 28: TABLE 9. DEVIATION from reference v
- Page 29 and 30: Comments Classifications must be ba
- Page 31 and 32: winter/spring, i.e. ice-covered per
- Page 33 and 34: Light conditions Introduction Light
- Page 35 and 36: TABLE 13. CURRENT CONDITIONS: turbi
- Page 37 and 38: Acidity / acidification Introductio
- Page 39 and 40: industrial pH). The change in acidi
- Page 41 and 42: The pre-industrial concentration of
- Page 43 and 44: very high degree of reliability and
- Page 45 and 46: TABLE 19. CURRENT CONDITIONS: metal
- Page 47 and 48: TABLE 22. DEVIATION from reference
- Page 49: TABLE 24. (continued) Cu Zn Cd Pb C
- Page 53 and 54: Assessment of current conditions TA
- Page 55 and 56: TABLE 29. CURRENT CONDITIONS: poten
- Page 57 and 58: TABLE 32. DEVIATION from reference
- Page 59 and 60: References Cronberg, G., Lindmark,
- Page 61 and 62: (see Appendix 1). If submerged and
- Page 63 and 64: References Andersson, B. (1998): Va
- Page 65 and 66: The genera in question and their tr
- Page 67 and 68: Benthic fauna Introduction Benthic
- Page 69 and 70: TABLE 41. CURRENT CONDITIONS: botto
- Page 71 and 72: Comments The assessment must be bas
- Page 73 and 74: has yielded better results than did
- Page 75 and 76: TABLE 45. CURRENT CONDITIONS: fish,
- Page 77 and 78: TABLE 46. DEVIATION from reference
- Page 79 and 80: TABLE 48. DEVIATION from reference
- Page 81 and 82: TABLE 48. (Contd.) Proportion of al
- Page 84 and 85: Presentation of data When using the
- Page 86 and 87: APPENDIX 1 Ceratophyllum demersum 1
- Page 88 and 89: APPENDIX 2 Calculation of index and
- Page 90 and 91: APPENDIX 2 Table 1b. Indicator gene
- Page 92 and 93: Genus Indicator value -------------
- Page 94 and 95: APPENDIX 2 45 Planorbis sp. 46 Anis
- Page 96 and 97: APPENDIX 2 214 Leuctra hippopus 215
- Page 98 and 99: APPENDIX 2 384 Tinodes waeneri 385
Swedish EPA (1993): Metals <strong>and</strong> the Environment – Status <strong>and</strong> Trends, Swedish<br />
EPA Report 4245.<br />
Norwegian EPA (1997): Klassifisering av miljøkvalitet i ferskvann. – Veiledning<br />
(”Classification of freshwater quality - Guidelines”) 97:04.<br />
50