WG ECOSTAT meeting - Ispra, 20 Mar 2012

BO2A METHOD (ES)

CW BENTHIC INVERTEBRATESNEA-GIG

Maria Dulce Subida & Pilar Drake

Experts for CW & TW benthic invertebrates

SPAIN - Andalusia

NEA-GIG CW BENTHIC INVERTEBRATE FAUNA BO2A METHOD - ES

Until October 2011, 3 IC approaches followed:

Traditional option 3 supported by pseudo-common metric, gave average good results but difficulties with assumptions drove us to look for an alternative Option 3a:

3a 3b alternative 3aCOMPARABILITY CRITERIA

BOUNDARY

BIASCLASS

AGREEMENT

OK for original boundariesbut difficulties with

assumptions

OK for original boundaries

Not assessed

(more stringent criteria)

OK for H-G boundary

Not OK for G-MCause: Biogeographical issue. Metrics highly dependent on

diversity not suitable for southern regions influenced by Mediterranean Sea.

M-AMBIBAT

Data from:

→ phase I: ES (N), FR, PT→ phase 2: ES (S)

proposed in phase II

BO2A intercalibrated with

accepted in phase I

- ES (north), FR

- PTES-AN (Andalusia, southern Spain, in the transition between Atlantic and

Mediterranean)

At WG ECOSTAT meeting in Oct 2011:

Green light for this IC exercise -> IC feasible

At IC validation workshop in Nov 2011:

Comparability procedure of IC guidance difficult to apply.Instructions by IC steering group to use an ecologically-based approach

Final IC approach using % of opportunistic polychaetes as yardstick:(final milestone report Dec 2011)

1. Identification of the sources of discrepancy and exclusion of outliers;

2. Exclusion of ES southernmost (ES-AN) samples and construction of the “North” (N) dataset ;

3. Comparability and harmonization of boundaries for BO2A, M-AMBI, BAT for the N dataset;

4. Application of the % of opportunistic polychaetes (%OP) as yardstick to compare the harmonized BO2A boundaries in the N dataset with the original boundaries proposed by ES-AN.

NEA-GIG CW BENTHIC INVERTEBRATE FAUNA BO2A METHOD - ES

Final IC approach using % of opportunistic polychaetes as yardstick:(final milestone report Dec 2011)

3. Comparability and harmonization of boundaries for BO2A, M-AMBI and BAT for the N dataset

Original boundaries of BO2A comparable with MAMBI and BAT from phase I, in the North dataset

BO2A M-AMBI BAT

H-G 0.83 0.77 0.79

G-M 0.50 0.53 0.58

approach 3a (from the guidance)

alternative 3a

BOUNDARY

BIASCLASS

AGREEMENT

BO2A more stringent anddifficulties with assumptions

OK for original boundaries

Not assessed

Low agreement only at G-M due to few data but:BO2A more stringent

complete N dataset depurated N

dataset

use BO2A original boundaries in next

step

NEA-GIG CW BENTHIC INVERTEBRATE FAUNA BO2A METHOD - ES

COMPARABILITY CRITERIA

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.10

25

50

75

100

EQR BO2A

% O

P

0 0.2 0.4 0.6 0.8 1 1.20

25

50

75

100

EQR BO2A

% O

P

27 %

0.83H-G

ES-AN original boundaries

55 %

0.50G-M

27 %

0.78H-G

ES-AN harmonized boundaries

55 %

South dataset

0.44G-M

55 %

27 %

Northdataset

Final IC approach using % of opportunistic polychaetes as yardstick:(final milestone report Dec 2011)

4. Application of the % of opportunistic polychaetes (%OP) as yardstick to compare the harmonized BO2A boundaries in the N dataset with the original boundaries proposed by ES-AN

NEA-GIG CW BENTHIC INVERTEBRATE FAUNA BO2A METHOD - ES

% OP = -84.98 EQR BO2A + 97.50

r2 = 0.99

% OP = -81.41 EQR BO2A + 90.44

r2 = 0.99

CONCLUSIONS:

Assessment method duly described during IC exercise

Sound ecological knowledge of IC datasets

Comparability of BO2A assessed following IC guidance

Several alternatives developed when guidance assumptions not met

Alternative comparability approach yielded sound results

IC procedure clear and reproducible

IC procedure analyzed, discussed and verified in IC validation workshop

IC results take into account biogeographical differences

IC RESULTS SHOW THAT BO2A IS AN ACCURATE METHOD FOR THE ASSESSMENT OF ECOLOGICAL QUALITY OF COASTAL WATERS IN SOUTHERN SPAIN

BO2ANorther

n regions

Southern regions

H-G 0.83 0.78

G-M 0.50 0.44

THE FINAL BOUNDARIES TO BE INCLUDED IN THE COMMISSION DECISION WOULD BE (see table):

No changes to M-AMBI and BAT boundaries

NEA-GIG CW BENTHIC INVERTEBRATE FAUNA BO2A METHOD - ES

THANK YOU FOR YOUR ATTENTION!

Sunset in one Andalusian CW-NEA by Alberto Arias (ICMAN-CSIC)