U.K. Reduced Species List (RSL) tool

Transcription

1 U.K. Reduced Species List (RSL) tool Emma Wells (Wells Marine), Martin Wilkinson, Paul Wood (Heriot-Watt University), Clare Scanlan (SEPA), Mike Best (EA) Contact: Clare Scanlan June 2011

2 Index I. General information II. Description of the method III. Data acquisition IV. Reference & Boundary conditions V. How to calculate the index VI. Examples

3 I. General Information Name of tool: Reduced Species List (RSL) Countries: UK and Ireland WISER ID: 25 Typology: Coastal waters BQE: Macroalgae GIG: North east Atlantic (NEA) Pressures responded to: Toxic substances, disturbance; (eutrophication is a secondary pressure, when severe) References: Wells,E., Wilkinson,M., Wood,P. & Scanlan,C The use of macroalgal species richness and composition on intertidal rocky shores in the assessment of ecological quality under the European Water Framework Directive. Marine Pollution Bulletin, 55, Wells, E Water Framework Directive development of classificaiton tools for ecological assessment: Macroalgae Species Richness. U.K. T.A.G. Report, January 2010, SNIFFER

4 II. Description of the method (i) The tool is a multi-metric method, based on the premise that species richness is related to water quality. It applies to natural, stable, hard, rocky substrata in coastal waters. Shore habitat diversity can affect species richness. Taxa counts are therefore normalised using a de-shoring factor to account for habitat diversity.

5 II. Description of the method (ii) Using a database of ca. 350 single occasion sampling sites, three overlapping species lists were compiled for the United Kingdom and Ireland. These reduced lists selected the approx. 70 most common species for each of those geographic areas. Species List Eng Wales RoI NI Scot Eng Eng Wales RoI NI Scot Eng Greens Reds Blidingia sp Aglaothamnion/Callithamnion Bryopsis plumosa 1 Ahnfeltia plicata Chaetomorpha linum Audouinella purpurea 1 Chaetomorpha mediterranea 1 1 Audouinella sp 1 Chaetomorpha melagonium 1 1 Calcareous encrusters Cladophora albida 1 Callophyllis laciniata 1 Cladophora rupestris Catenella caespitosa 1 1 Cladophora sericea Ceramium nodulosum Enteromorpha sp Ceramium shuttleworthanium Monostroma grevillei 1 Ceramium sp. 1 Rhizoclonium tortuosum 1 Chondrus crispus Spongomorpha arcta 1 Corallina officinalis Sykidion moorei 1 Cryptopleura ramosa Ulothrix sp 1 Cystoclonium purpureum Ulva lactuca Delesseria sanguinea 1 Sub-totals Dilsea carnosa Browns Dumontia contorta Alaria esculenta 1 1 Erythrotrichia carnea 1 1 Ascophyllum nodosum Furcellaria lumbricalis Asperococcus fistulosus 1 1 Gastroclonium ovatum 1 Chorda filum 1 1 Gelidium sp. 1 1 Chordaria flagelliformis 1 Gracilaria gracilis 1 Cladostephus spongious Halurus equisetifolius 1 Desmarestia aculeata 1 Halurus flosculosus 1 Dictyosiphon foeniculaceus 1 Heterosiphonia plumosa 1 Dictyota dichotoma Hildenbrandia rubra 1 1 Ectocarpus sp Hypoglossum hypoglossoides 1 Elachista fucicola Lomentaria articulata Fucus serratus Lomentaria clavellosa 1 Fucus spiralis Mastocarpus stellatus Fucus vesiculosus Melobesia membranacea 1 Halidrys siliquosa Membranoptera alata Himanthalia elongata Nemalion helminthoides 1 Laminaria digitata Odonthalia dentata 1 1 Laminaria hyperborea 1 1 Osmundea hybrida Laminaria saccharina Osmundea pinnatifida Leathesia difformis Palmaria palmata Litosiphon laminariae 1 Phycodrys rubens 1 Pelvetia canaliculata Phyllophora sp Petalonia fascia 1 Plocamium cartilagineum Pilayella littoralis Plumaria plumosa Ralfsia sp Polyides rotundus 1 1 Saccorhiza polyschides 1 Polysiphonia fucoides Scytosiphon lomentaria Polysiphonia lanosa Sphacelaria sp 1 Polysiphonia sp Spongonema tomentosum 1 1 Porphyra leucosticta 1 Sub-totals Porphyra umbilicalis Ptilota gunneri 1 Rhodomela confervoides Rhodothamniella floridula Sub-totals Totals

6 II. Description of the method (iii) Other community composition parameters are assessed: Ecological Status Group (ESG) ratio Percentage of red taxa present Percentage of green taxa present Percentage of opportunistic taxa present Abundance is not assessed, as this is naturally highly variable on rocky shores Each sub-metric is scored and then the average calculated.

7 III. Data acquisition (i) Sampling frequency: Once per annum; twice per reporting cycle Sampling season: Late May to September Survey area: Between high water and low water on spring tides; between 100m and 300m of shore length, or discrete shore area Shore description: No. of sub-habitats & other physical parameters

8 III. Data acquisition (ii) No. of sites per WB: Minimum of 3 Time: Between 0.5 and 2.5hours, depending on the length and complexity of the shore Taxonomic level: Mixed taxon level, but generally to species

9 IV. Reference & Boundary conditions Reference conditions were derived by a combination of multivariate data analysis of ca. 350 single occasion sampling sites and expert judgement Boundary conditions were also derived from the same dataset Class Bad Poor Moderate Good High EQR Normalised Species richness Percentage of greens Percentage of reds ESG ratio Percentage of opportunists Note: Boundary conditions vary slightly for each of the three separate species lists

10 V. How to calculate the index (i) Species richness totals are adjusted to account for the effect of shore diversity on total species number. This is known as de-shoring, and uses the relationship Richness = a + b (cshore) where a, b and c are calculated from the original dataset Shore description value Predicted species richness De-shoring factor

11 V. How to calculate the index (ii) For Species richness, % of red algae and ESG1/ESG2 ratio the EQR is calculated as follows: EQR = {(value lower CR)/(CW) x EQR BW} + lower EQR BR For % green algae and % opportunists the EQR is calculated as follows: EQR = Upper EQR BR - {(value lower CR)/(CW) x EQR BW}

12 Example 1 VI. Example 1 High status Shore score on form = 15 => de-shoring factor of 1.00 Species richness = 40 Normalised species richness = (40 x 1) = 40 EQR = {(40-35)/35 x 0.2} = 0.83 % red algae = 50 EQR = {(50-45)/10 x 0.2} = 0.70 ESG ratio = 1.20 EQR = {( )/0.2 x 0.2} = 1.0 % green algae = 10 EQR = 1.0 {(10-0)/12 x 0.2} = 0.83 % opportunists = 12.5 EQR = 0.8 {( )/5 x 0.2} = 0.70 Average EQR of sub-metrics = ( )/5 = 0.81 Final EQR of 0.81 = High status

13 VI. Example 2 Moderate status Example 2 Shore score on form = 14 => de-shoring factor of 1.07 Species richness = 14 Normalised species richness = (14 x 1.07) = EQR = {( )/12 x 0.2} = 0.37 % red algae = EQR = {( )/20 x 0.2} = 0.34 ESG ratio = 1.00 EQR = {( )/0.2 x 0.2} = 0.8 % green algae = EQR = 1.0 {( )/10 x 0.2} = 0.57 % opportunists = EQR = 0.8 {( )/5 x 0.2} = 0.63 Average EQR of sub-metrics = ( )/5 = 0.54 Final EQR of 0.54 = Moderate status