INTERCALIBRATION OF PHYTOPLANKTON IN TRAC WATERS. Shane O Boyle and Georgina McDermott Aquatic Environment EPA, Richview, Dublin, 12 October 2011

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1 INTERCALIBRATION OF PHYTOPLANKTON IN TRAC WATERS Shane O Boyle and Georgina McDermott Aquatic Environment EPA, Richview, Dublin, 12 October 2011

2 The problem eutrophication in TRAC waters

3 The problem eutrophication in TRAC waters

4 Normative Definitions Phytoplankton High Good Moderate The composition and abundance of the phytoplanktonic taxa are consistent with undisturbed conditions. The average phytoplankton biomass is consistent with the type-specific physicochemical conditions and is not such as to significantly alter the type-specific transparency conditions. Planktonic blooms occur at a frequency and intensity which is consistent with the type specific physicochemical conditions. There are slight changes in the composition and abundance of phytoplanktonic taxa. There are slight changes in biomass compared to the type-specific conditions. Such changes do not indicate any accelerated growth of algae resulting in undesirable disturbance to the balance of organisms present in the water body or to the physicochemical quality of the water. A slight increase in the frequency and intensity of the type specific planktonic blooms may occur The composition and abundance of phytoplanktonic taxa differ moderately from type-specific conditions. Biomass is moderately disturbed and may be such as to produce a significant undesirable disturbance in the condition of other biological quality elements. A moderate increase in the frequency and intensity of planktonic blooms may occur. Persistent blooms may occur during summer months.

5 TRAC methods Phase I coastal waters Chlorophyll biomass (90 th %ile and median over the growing season (March to September). Frequency of phytoplankton cell counts (individual taxon) above a pre-defined threshold. Frequency of Phaeocystis cell counts above a pre-defined threshold (not being applied by Ireland). No method for species composition. EQRs for chlorophyll biomass (worst case) and phytoplankton cell counts normalised and then combined.

6 TRAC methods Phase II transitional waters Chlorophyll biomass (90 th %ile and median over the summer growing season). Frequency of phytoplankton cell counts (individual taxon) above a pre-defined threshold (500,000 cells / litre up to 17 ppt). No method for species composition. EQRs for chlorophyll biomass (worst case) and phytoplankton cell counts normalised and then combined.

7 TRAC GIGs, MS, Typology, Methods, Pressures Ireland participated in the North East Atlantic Geographical Intercalibration Group (NEA GIG) Composed of BE, DK, FR, DE, IE, NL, NO, PT, ES, SE and UK Two Types: NEA 1/26 (Exposed or sheltered, euhaline, shallow) NEA 11 (Transitional water) Option 2 Common Metric Pressure = nutrient enrichment

8 Reference Criteria for NEA GIG Reference criteria were based on contemporaneous data collected from undisturbed water bodies that were considered to be close to or at reference as determined by expert judgment, the Article 5 Characterisation report and supporting environmental data.

9 Boundary Setting Procedure used The class boundary procedure was based on the analysis of data collected by the WFD METRIC (Marine Ecological Tools for Reference, Intercalibration and Classification) project. High/good boundary = reference condition * 1.5 This resulted in a high/good boundary value of 2.5 (2.4) and 5.0 (5.1) mg/m3 for the median and 90 percentile respectively. The good/moderate boundary was set at twice the high/good boundary and is therefore set at 5 and 10 mg/m³ for the median and 90 percentile respectively. For elevated cell counts a threshold of 250,000 cells/litre was set with a frequency of 16.7% (reference), 20% (high/good) and 39% (good moderate).

10 Boundary Setting Procedure used Metric data Water Body Salinity Chl a (mg/m³) Median Chl a (mg/m³) 90 %ile All regions and types combined (778) 1.60 (1106) 3.48 (1106) Atlantic (Reference) (296) 1.64 (657) 3.40 (657) Irish Sea (482) 1.60 (449) 3.74 (449)

11 Boundary Setting Procedure outcome across GIG

12 Boundary setting procedure for elevated cell counts

13 Importance of extraction method Median and 90%ile Chlorophyll a (mg/m³) boundary criteria for coastal waters for different pigment extraction techniques. Extractant Cold Acetone Hot Methanol Boundary Median 90%ile Median 90%ile high/good good/moderate

14 Outcome of benchmarking process For coastal waters the application of the benchmarking process showed that French, Danish, German and Irish toolkits did not need adjusting (i.e. within a quarter of a class) For transitional waters the benchmarking process indicated that the national boundaries could be adjusted downwards if felt necessary.

15 Implications for Ireland and Future Work Applying the boundaries from phase 2 to transitional waters resulted in 12 of 30 water bodies being placed at less than good. Poor (e.g., Castletown estuary, Swilly estuary, Upper Bandon estuary) Moderate (e.g., Ilen estuary, North Channel, Lower Bandon estuary) Good (Garavogue estuary, Corrib estuary) High (Westport Bay, Camus Bay, Lower Shannon estuary) Results from phase 2 are in good agreement with previous assessments (e.g., TSAS) but now comparable and consistent across Europe. Future Work Further consideration of the outcome of the bench marking process. Investigating the use of cell biovolume data Species composition

16 Acknowledgements Georgina McDermott, Tone Noklegaard, METRIC Team, EPA lab staff

17 INTERCALIBRATION OF PHYTOPLANKTON IN TRAC WATERS Shane O Boyle and Georgina McDermott Aquatic Environment EPA, Richview, Dublin, 12 October 2011