1. Lake Macroinvertebrate IC EC-GIG
Gabriel Chiriac for RO (lead)
Gabor Varbiro for HU
Georg Wolfram for BG
Jürgen Böhmer for statistics

2. Methods, Pressures IC OptionHU RO BG
Own method
Adopts HU method
Eutr., Hymo, lake use
IC Option
Assessment methods differ and sampling is too different for option 3 (sampling area, sampled habitats, determination level etc.)
 Option 2 (common metrics)
Pressure relationships:
Assessments, sampling and pressures on lake level
Demonstrated well for Hu and RO
Not possible for BG (only one lake)

3. Data Basis HU: 29 samples in 20 lakes RO: 232 samples in 22 lakes
BG: 3 samples in 1 lake  no statistics possible  BG adopted HU method
Whole lake pressure data: chemistry, landuse, hydromorphology, recreational pressure and fisheries
Multivariate stressor index chosen for standardisation, common metric selection and other analyses:
All lakes are IC-Type L-EC1

4. Benchmarking
Only very few reference lakes  reference benchmarking not possible
 Continuous benchmarking applied
Linear mixed models with with the biological metrics as dependent variable, the combined pressure variable as covariates and the country as random factor; slope as fixed and intercept as random factors  intercept deviation
Subtraction method for standardisation of the metrics

5. Common Metrics
All candidate metrics were standardised by continuous benchmarking as described before
Standardised single metrics were normalised using 10- and 90-%tiles of all metric values as anchors to get comparable values for the different metrics  1 near reference conditions, 0 at worst status
Final intercalibration common metric (ICM) average of normalised Shannon-Wiener diversity, BMWP and % dominant families, thus covering all WFD criteria (diversity, sensitive/tolerant taxa, composition):
ICM = ([ShW_norm]+[BMWP_norm]+[domFam_norm])/3

6. Ecological Quality Ratios Good-moderate boundary
Boundary comparison
Romania‘s boundaries needed adjustment
 Final boundaries (agreed and accepted):
Member State
Classification
Ecological Quality Ratios
Method
High-good boundary
Good-moderate boundary
HU/BG
HMMI lakes
0.85
0.65 RO
ECO-NL-BENT
0.93
0.60

7. Suitability of the HU method for BG
BG assessments with HU method fit into the pressure response curve of HU (and also the EQR / common metric relationship)  The BG lake can be treated like a HU lake

8. Conclusions Boundaries are agreed and accepted
Ecercise was reviewed and accepted with minor changes, which have been carried out