1. Alpine GIG phytoplankton group
ECOSTAT | 27 June 2011
Georg Wolfram

2. Member States Špela Remec-Rekar Eberhard Hoehn Ursula Riedmüller
LBH
Christophe Laplace-Treyture
Cemagref
Georg Wolfram
DWS Hydro-Ökologie GmbH
Maria Friedl
Kärntner Inst. f. Seenforschung
Fabio Buzzi
Arpa Lombardia
Giuseppe Morabito
CNR, Istituto per lo Studio degli Ecosistemi
Špela Remec-Rekar
Environmental Agency of the Republic of Slovenia

3. Alpine GIG – an easy job? Small and homogenous GIG
Few MS and full participation
Little variability in lake types (50 – 800 m a.s.l.)
Long data series (since 1930s)
Comparable sampling and analytical methods
Clear pressure – impact relationship

4. 1 pressure – 2 parameters – 4 methods
Pressure = eutrophication
Biomass (chlorophyll-a and/or biovolume) + Taxonomical composition (trophic index)
Finalized methods in AT(+SI), GE, FR and IT

5. Alpine blooms? WISER deliverable: rare at TP <20–25 µg L–1
Annex V of WFD: “Persistent blooms may occur”
The risk of missing a bloom is thus very high  high uncertainty and stochasticity
In order not to add a metric with high uncertainty and little relevance to the existing, well working assessment methods, the Alpine GIG has agreed not to include blooms in their classification systems.

6. Overview of Methods MS biomass tax. composition
chl-a biovolume trophic index
AT avg avg Brettum index
FR avg – MCS
GE avg/max avg PTSI + algal classes
IT avg avg PTI
SI avg avg Brettum index
blue = annual mean, red = mean of vegetation season

7. Combination rules AT + SI + IT Total biovolume EQR nEQR nEQR
Arithmetic mean
Chlorophyll-a
EQR
nEQR
nEQR
Arithmetic mean
Trophic index
EQR
nEQR

8. Reference conditions Tiered approach for defining reference conditions
Definition of general reference criteria for lakes
Definition of reference criteria for lakes, for single BQE only
Definition of reference criteria for sites (within lakes)
Key criteria for phytoplankton: TP concentration
≤ 8 µg L–1 (L-AL3)
≤ 12 µg L–1 (L-AL4)
Modified approach
GE: using LAWA index
FR: emphasis on land use and population density

9. Reference conditions Lake (n = 1 – 9) TP ann.avg TP spring circ Chl-aBV
Achensee 4
1.13
0.09
Alpsee bei Füssen 6
1.33
0.43
Altausseer See
1.35
0.16
Attersee 2 3
1.23
0.36
Bohinjsko jezero 5
1.20
0.12
Eibsee
1.44
0.21
Fuschlsee
0.55
Grundlsee
0.90
0.07
Heiterwanger See
1.29
0.13
Königssee
1.66
0.39
Millstätter See
0.29
Obersee
3.06
0.51
Ossiacher See
0.41
Plansee
Starnberger See 7
2.06
0.57
Sylvensteinsee
1.19
0.14
Traunsee
2.00
0.52
Walchensee
1.88
Weißensee
0.22
Wolfgangsee G
Wolfgangsee W
0.23
Wörthersee
Zeller See
0.45

10. Reference conditions TP ann. avg TP spring circ. Chl-a BV mean 5 4
1.52
0.30
median
1.33
0.29
min 2
0.90
0.07
max 7 6
3.06
0.57
75%perc
1.77
0.42
90%perc
2.04
0.52
95%perc
2.36
0.55

11. Reference conditions L-AL3 reference value H/G boundary phase 1
0,60
ranges
0,50
0,40
ranges
Total biovolume [mm3 L-1]
0,30
0,20
0,10
0,00
median
90%p
70%p
90%p
95%p
phase 1
new calculation

12. Reference conditions L-AL3 reference value H/G boundary
3,00
2,50
2,00
chlorophyll-a [µg L-1]
1,50
1,00
0,50
0,00
median
90%p
70%p
90%p
95%p

13. Reference conditions
New calculations: roughly the same results for reference values and H/G boundary (changes especially in percentiles)  decided to keep the old values from phase 1

14. Benchmark standardization
Benchmark standardization serves to homogenize the EQR results of common datasets where needed, minimising typological and methodological differences between the Member states which may otherwise influence the comparability of their classifications (especially: biogeographical differences).

15. Benchmark standardization
L-AL4

16. Benchmark standardization
L-AL3

17. Benchmark standardization
Comparability checking without benchmark standardization
By manually setting the offset to zero

18. Boundary comparison

19. Boundary comparison 1. Relatedness 2. Boundary bias
2. Boundary bias
3. Class difference
Regressions with PCM
H/G bias_CW
Absolute Class Diff.
L-AL3
L-AL4
AT/SI - PCM
0,87
0,86
AT/SI
-0,10
0,32
FR - PCM
0,34
0,50 FR
-0,07
0,15
0,47
0,53
GE - PCM
0,79
0,85 GE
0,04
0,33
0,30
IT - PCM
0,83
0,88 IT
0,01
-0,12
0,29
min/max
40%
57%
G/M bias_CW
Count
570
276
Pearsson corr. coeff.
-0,11
0,13
0,93
-0,01
0,59
0,71
0,10
0,89
0,92
0,00
-0,20
0,91
0,94
min R2 < ½ max R2
boundary biases ≤0.25
correlation coefficients ≥ 0.5
avg absolute class difference <1.0

20. Summary All MS have submitted national methods
Only slight deviation from phase 1 results
Good agreement between national methods
IC completed

21. Comparison of BQEs lake IC type phytopl macroph fish key pressure
final
ATT
L-AL3
0.93
0.92
morph littoral
MATT
L-AL4
0.90
0.79
ALT
0.86
bathing
WOLF
0.80
shipping
FAAK
1.00
0.53
hymo
OBTR
0.62 eu
WORTH
0.65
0.68
MILL
0.67
0.59
MOND
0.69
0.77

22. Thank you