Report on Harmonisation of freshwater biological methods

• Macroalgae: No• Benthic invertebrates: Yes; biotic integrity index• Fish: No• Physicochemical quality: Yes; BOD7, total N, total P• Pressure criteria: Yes; Land use (%), wastewater discharges (approximateamount of discharges), recreational useLatvia• WFD compatible? No• Use of reference physico-chemical conditions (? But reference conditionquestions were all answered with no), statistical analyses of physico-chemicalvalues.• Criteria (P total, N total, BOD5, N/NO3, N/NO2, N/NH4, P/PO4, Chlorophylla) the lowest and the highest quartiles were used for approximate defininghigh/good or the good/moderate class boundaries + expert judgement• Phytoplankton: No 5 out of 6 sites• Phytobenthos: No• Macrophytes: No• Macroalgae: No• Benthic invertebrates: No• Fish: No• Physicochemical quality: Yes; P total, N total, BOD5, N/NO3, N/NO2,N/NH4, P/PO4, Chlorophyll a• Pressure criteria: NoNetherlands• WFD compatible? Yes• Modification of method presented in Van den Berg et al., (2002). Boundaryhigh/good: statistical variation in data, 90% percentile of reference values• good/moderated: class width of good is assumed to be similar as class widthfor high.• Phytoplankton: Yes; mean chlorophyll a concentration (summer period).• Phytobenthos: No• Macrophytes: Yes; 3 out of 3 sites; area covered by submerged macrophytes,1 site including charophytes.• Macroalgae: only 1 site; Charophytes were included in area covered bysubmerged macrophytes.• Benthic invertebrates: No• Fish: No• Physicochemical quality: Yes; total P• Pressure criteria: NoNorway• WFD compatible? No• National classification system (SFT-guidance 1997:04) combined with expertjudgement120