Intercalibration of Mediterranean Lakes and Reservoirs Phytoplankton

Mediterranean Lakes and Reservoirs Phytoplankton Intercalibration Caridad de Hoyos José Pahissa Jordi Catalán Presented by: Irene Carrasco

1) PARTICIPATION

2) METHODS GASRLP  Greek Assessment System for Reservoirs and Lakes Phytoplankton (Under development) ITMET*  Italian Method (Reservoirs) ITMET**  Italian method (Lakes) IPLAC  Lake Phytoplankton Index ROMET  Romanian method MASRP  Mediterranean Assessment system for Reservoirs Phytoplankton SSLP  Spanish System for Lakes Phytoplankton (Composition part under development).

3.1) COMPLIANCE CHECK • According to the information sent by the participating countries, all the methods are compliant with the WFD normative definitions. • Furthermore, within the MedGIG data set, we have analyzed the relation between the methods and the pressures.

3.2) COMPLIANCE CHECK Methods aplied in Siliceous reservoirs are significantly correlated to pressures (TP). Methods aplied in Calcareous reservoirs are not related to pressures (TP) ROMETRomania MASRPSpain,Portugal,Cyprus IPLACFrance ITMETItaly

3.2) COMPLIANCE CHECK Methods applied in Calcareous reservoirs are significantly correlated to TP when high alkalinity basins are removed. ROMETRomania MASRPSpain,Portugal,Cyprus IPLACFrance ITMETItaly

3.2) COMPLIANCE CHECK Methods applied in Calcareous reservoirs are significantly correlated to WISER common metrics. ROMETRomania MASRPSpain,Portugal,Cyprus IPLACFrance ITMETItaly

4.1) FEASABILITY. Typology (1st Phase) • 1st Phase

1) Comparable pressure levels. 4.2) FEASABILITY. Typology (2nd Phase)

4.2) FEASABILITY. Typology (2nd Phase) 2) Several metric-based statistical analysis agree that there are significant differences among Calcareous and Siliceous reservoirs, but there are no significant differences between “wet” and “arid” reservoirs.

4.2) FEASABILITY. Typology (2nd Phase) 3) Correspondance analysis and discriminant analysis based on species abundance separate four groups. Calcareous arid Calcareous wet Siliceous Arid Siliceous wet

4.2) FEASIBILITY. Typology (2nd Phase) • Lakes: Only one intercalibration type, characterized by: • 1) Shallow depth or deep (Mean depth 3-15 m or >15 m) • 2) Calcareous ( > 1 meq/L) • 3) Altitude from 0 to 1000 m.a.s.l.

4.3) FEASIBILITY • National typologies are comparable with the IC types in most cases, except in France. • ALL intercalibrated methods attempt to assess the same pressure effect: Eutrophication. • ALL methods consider samples from the pelagic zone (Euphotic depth 2.5*SD), based on the growing season, except Italy.

ITMET (Only Summer) VS ITMET (All year) 80 % of the reservoir years which could be analysed by the two methods, show less than 30 % difference between them. 4.3) FEASIBILITY

5.1) MEP and Reference setting (Pressures) • Pressure Screening: Compulsory accomplishment of rejection limits. No more than two reference (MEP) limits can be surpassed. • Secondary pressures must be low: • Recreation activities. • Exploitation of fish population by fishery. • Excluded if Presence of Dreissena polymorpha (Zebra mussel). The same criteria used for Lakes!

5.2) MEP and Reference setting (Biological parameters) Thorough revision of the metrics. Two more filtering criteria were considered: • RESERVOIRS: Biological metrics revised where chlorophyll-a, biovolume, IGA and % Cyanobacteria. If two or more of these samples are above the G/M boundaries established in the first phase, the reservoir is not considered as MEP. 2)LAKES: Those lakes whose median value for any of these metrics (chlorophyll-a, biovolume or PTIot) was above the third quartile of the set selected with the pressure filter were not considered. The rest of the lakes were marked as reference.

5.3) MEP and Reference setting (Sites)

Double approach methodology for G/M establishment: • Parameters checked along the pressure gradient. Third quartile of 20-50 ugTP/L marks the discontinuity. • (2.56 mm3/L) 6.1) Boundary setting MASRP  NMASRP • New 2nd Phase boundaries for MASRP (including Cyanobacterial biovolume as bloom metric) are proposed.

6.1) Boundary setting Double approach methodology for G/M establishment: Anchor method, E1 = MEP value E0 = Most degraded case using 95% (Cal) or 85% (SW) (WISER Deliverable D3.1-2: Report on phytoplankton bloom metrics) (2.9 mm3/L) • New 2nd Phase boundaries for MASRP (including Cyanobacterial biovolume as bloom metric) are proposed.

6.1) Boundary setting • New 2nd Phase boundaries for MASRP (including Cyanobacterial biovolume as bloom metric) are proposed. The mean of both approaches was considered as the G/M for each metric. (2.56 + 2.9) /2 = 2.73 (2.7)

6.2) Boundary setting • The final boundaries for the metrics are calculated for Calcareous (Arid+Wet) since all statistics were similar in both groups and the increased data set once joined together was highly recommendable; and for Sil. Wet, since not enough data was available for Sil. Arid reservoirs, but merging groups was not recommended by some GIG members: • Cyanobacterial BV gave a 0.1 but it was changed to 0.5 through consensus and scientific reasoning (The trophic spectrum covered is very narrow). At 0.5, the boundary is more coherent with other GIGs and the WHO.

6.2) Boundary setting Box-plot of Cyanobacteria BV in MEP (R) and no MEP in two types of Mediterranean reservoirs Number of reservoir years which fall within different cyanobacterial biovolume classes. Most cases fall in the first (and lowest) category.

Siliceous wet. At MEP sites, type communities are usually composed of Chrysophytes, some Diatoms and Chroococcals. As we approach the G/M status these groups´ importance falls, and some genres of Cyanobacteria start to dominate. 7) Biological communities at MEP and G/M

7) Biological communities at MEP and G/M Siliceous wet. At MEP sites, type communities are usually composed of Chrysophytes, some Diatoms and Chroococcals. As we approach the G/M status these groups´ importance falls, and some genres of Cyanobacteria start to dominate.

7) Biological communities at MEP and G/M Calcareous. At MEP sites, type communities are usually composed of some Diatoms, specially from the genre Cyclotella. As we approach the G/M status this groups´ importance falls, and some genres of Cyanobacteria and Chlorococcals start to dominate.

8.1) Comparability tests (Benchmark standardization) • Reservoir benchmark normalization is not necessary since there are no differences between the MEP reservoirs of different countries (Student´s T test comparisons´ p-values). • Lake benchmark normalization is not necessary since there are only reference sites from Spain (6), and the contribution of data from the rest of participating countries is not sufficient for defining alterative benchmark sites. • Another methodologies (Macrophyte XGIG) will be applied in order to try to find alternative benchmark sites.

8.2) Comparability tests Opt 3a (Reservoirs Calcareous 1st Phase)

8.3) Comparability tests Opt 3a (Reservoirs Siliceous wet 1st Phase)

8.4) Comparability tests Opt 3a (Reservoirs Calcareous 2nd Phase)

8.5) Comparability tests Opt 3a (Reservoirs Siliceous wet 2nd Phase)

8.6) Comparability tests Regression (Lakes Calcareous 2nd Phase) • Just two methods available, ITMET and IPLAC. • Is the regression significant? • Is average absolute class difference sufficiently low?

8.7) Comparability tests Regression (Lakes Calcareous 2nd Phase) • Visualize boundary equivalence (G/M and H/G) • The difference must be lower than 0.25 class equivalent units.

Thank you for your attention.

Intercalibration of Mediterranean Lakes and Reservoirs Phytoplankton