Intercalibration : a “WFD compliant” boundary comparing procedure WG 2A ECOSTAT meeting - Ispra, October 7-8th, 2004 Mediterranean, Alpine, Central - Baltic River GIGs Scientific input from Intercalibration : a “WFD compliant” boundary comparing procedure Jean-Gabriel WASSON UR BEA/LHQ, Lyon, France 1

IC problems for Rivers Ancient, different methods sampling, laboratory and concepts Extensive monitoring networks in all MS Various pre-existing classifications (MS and / or QE) (preliminary) Ecological Status boundaries in most MS Not possible to construct a common boundary setting protocol on such different tools

Classification methods (1) Pre-existing Index and related classifications Variable number, definition, extension of classes valid for all types ? Reference ?

Classification methods (2) REF value = Median sites EQR 1 maximum alteration : 0 « Old index » transformed in EQR Boundaries values adapted to type Reference independent from pressures REFCOND Guidance

Classification methods (3) REF value = maximum observed ? minimum value = minimum observed ? EQR 1 Multivariate analysis & classification e.g. STAR dependent from the dataset ?

Classification methods (4) Previous classification of sites according to pressures Sites Biological metrics are adjusted to discriminate the 3 groups of sites Index values H + G M L + B FAME & French « indice poisson » dependent from the pressure classification

IC objectives : WFD concepts & normative definitions To ensure that boundaries (H/G and G/M) correspond to the same level of ecosystem alteration between MS We compare the boundaries, not the methods.. Ecosystem alteration is a deviation from Reference Conditions Necessity to include the Reference Conditions in the IC process Necessity to evaluate the Ecosystem alteration with metrics consistent with WFD normative definitions 1

Comparing MS boundaries If 3 MS get for G/M boundary : EQR 0.6, 0.7, 0.8 Is it a difference in Method or Ecosystem alteration ? BB 0.7 CC 0.6 AA 0.8 No major difference OK WFD compliant Common Metrics 0.7 0.6 0.8 Major differences => Harmonization

natural (biogeographical) and methodological differences ? How to normalize natural (biogeographical) and methodological differences ? Include Reference Sites in the dataset H/G 30 35 38 G/M 22 25 25 Member State AA BB GG e.g. : number of taxa Ref 35 40 45 Mini 0 2 1 EQR ? ?? Common metric = loss of taxa (in EQR)

Comparability of Reference Methods & Criteria for the selection of reference sites MS that have defined their RC agreed that the level of exigency was comparable (despite different methods) How to derive a Reference Value to calculate EQR The median of the values observed in reference sites is the most logical and robust statistics (generally agreed).

How to comply with the Normative Definitions of Ecological status ? Invertebrates in rivers good / moderate Taxonomic composition and abundance level of diversity Disturbance sensitive taxa Moderate status : Major taxonomic groups absent how much is slight ?

WFD compliant metrics... Taxonomic composition & abundance Diversity Definition Nb Taxa Total number of taxa (family level) EPT Taxa Number of Ephemera, Plecoptera and Trichoptera families Diversity index Shannon-Wiener diversity index, or Pielou (evenness) ASPT Average Score Per taxa (from BMWP table) GOLD% 1 – (relative abundance of Gastropoda + Oligocheta + Diptera) log10 Sel ETD log10 (number of individuals) from selected families of Ephemeroptera, Trichoptera, and Diptera Taxonomic composition & abundance Diversity Sensitive taxa Major groups

...responding to a wide range of pressures.

Common metrics currently tested for Central / Baltic and Mediterranean GIGs

How to compare boundaries ? e.g. IBGN vs ICM - Type R-M1 IBGN protocol samples quantitative faunistic lists Reference Sites included IBGN ICM Median of Ref. samples EQR IBGN ICM Slight deviation from REF = mean class : 18% maximum : 25%

How to compare boundaries ? Type R-C2 - Spain & France MMI (Galicia) R2 : 0.915 R2 : 0.796 France IBGN

If Reference is not available ? The work is not yet done.. A Pilot can be run with different normalisation procedure ( e.g. Q75th of High class) RC should be available for the real exercise Ref sites cannot be found for some types or MS (too much alteration) Seek for RC in other MS Derive a common procedure to define RC Choose another option