Lakes and Watercourses

More documents

Recommendations

Info

Internationally, the most widely accepted framework for environmental indicators is based on PSR-chains (Pressure-State-Response). Indicators are chosen which reflect the relationship between environmental effects, and/or there causes and measures taken. There is also a more sophisticated version, called DPSIR (Driving forces-Pressure-State-Impact-Response). Variants of the PSR/DPSIR systems are used by, among others, the OECD, the Nordic Council of Ministers, the United Nations, the World Bank, the European Union's Environmental Agency. ASSESSMENT PROCEDURE Measurements/data Assessment of current conditions — indicates environmental effects associated with current conditions Assessments of deviation from reference values — indicates environmental impact of human activity Assessment of current conditions Wherever possible, the scale used in assessments of current conditions is correlated with effects on different parts of the ecosystems and their biodiversity, or on human health (”effect-related classification”). In some cases, the assessment is based only on a statistical distribution of national data (”statistical classification”). The scale is usually divided into five classes. Where the assessment is based on effects, Class 1 indicates conditions at which there are no known negative effects on the environment and/or human health. The remaining classes indicate effects of increasing magnitude. Class 5 includes conditions leading to the most serious negative effects on the environment and/or human health. Due to wide natural variations, especially with regard to biological phenomena, the indicated effects are not always the result of human activities, in which case they can not be labelled as “negative”(see below). Where the assessment is based only on a statistical distribution, there is no well-defined relationship between effects and class limits. It should be noted that parameters that are evaluated on the basis of different criteria cannot be compared with each other. Reference values Ideally, the reference value for a given parameter represents a natural state that has not been affected by any human activity. In practice, however, reference values are usually based on observations made in areas that have experienced some slight human impact. In some cases, historical data or model- 11
ased estimates are used. Given that there are wide natural variations of several of the parameters, reference values in many cases vary by region or type of ecoystem. Deviations from reference values The extent of human impact can be estimated by calculating deviations from reference values, which are usually stated as the quotient between a measured value and the corresponding reference value: Measured value Deviation = ------------------------------------- Reference value The extent of deviation is usually classified on a five-level scale. Class 1 includes conditions with little or no deviation from the reference value, which means that effects of human activity are negligible. The remaining classes indicate increasing levels of deviation (increasing degree of impact). Class 5 usually indicates very significant impact from local sources. Organic pollutants and metals in heavily polluted areas are dealt with in greater detail in a separate report, Contaminated Sites, which includes a further sub-division of Class 5, as follows: Contaminated Sites Impact from point sources: None/ Moderate Substantial Very slight great Class 1 Class 2 Class 3 Class 4 Class 5 Other reports 12
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: included. In addition to a large nu
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 and 50: TABLE 24. (continued) Cu Zn Cd Pb C
Page 51 and 52: Swedish EPA (1993): Metals and the
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
Page 100 and 101:
APPENDIX 2 (6) O/C index (Wiederhol
Page 102 and 103:
APPENDIX 3 Dace Stäm Leuciscus leu
Page 106:
REPORT 5050 Environmental Quality C
show all

Lakes and Watercourses

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?