Water Framework Directive Marine Plants Task Team Tools Paper ...

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EXAMPLE: Details Score Site Name West Angle, Milford Haven Shore Type Subhabitat Type No. of Subhabitats Other factors Predominantly large rock ridges/platforms and outcrops Large rockpools and basic rockpools present along with crevices and some overhangs (4) Four 4 No apparent presence of sand scour, natural turbidity or chalk shores Total score for shore descriptions 18 The shore description then forms part of the rocky shore metric. It was decided that simply using the total number of species recorded on a single shore was not sufficient in itself to classify the shore and other algal composition information would be required to assist with the final classification along with the shores descriptions. This also fulfils the requirements of the normative definitions to include some measure of composition. Although composition varies considerably general measures of composition can be used such as proportions of red, green and opportunist species. • Proportions of red and green species – the proportion of red species is known to increase with increasing environmental quality and in contrast the proportion of green species increases as the quality of a shore decreases mainly due to an increased presence of opportunists. The proportions of brown species stay relatively constant regardless of overall species richness. • Use of ecological status groups (ESG) – seaweed species can be used to indicate shifts in the ecosystem from a pristine state (ESG 1 – late successionals or perennials) to a degraded state (ESG 2 – opportunists or annuals). This is achieved by using the following measure ESG 1/ESG 2 (Orfanidis et al, 2001). • Proportion of opportunists including Blidingia sp., Chaetomorpha linum, Chaetomorpha mediterranea, Enteromorpha sp., Ulva lactuca, Ectocarpus sp., Pilayella littoralis, Porphyra leucosticta and Porphyra umbilicalis. 4 4 6
These different community factors could then be used to create a metric from which an ecological quality status could be established. Establishing quality status boundary levels In order to identify the potential occurrence of correlations between community composition and quality status, members of the Marine Plants Task Team tentatively assigned each site within the marine benthic algal database a level of quality; high, good, moderate, poor and bad. This was based on expert knowledge of each of the sites irrespective of their species number and considering the proximity and magnitude of direct and indirect effluent discharges. This could later be used to establish the quality status boundary levels for each class. Each of the species richness and composition attributes was compared with the predicted quality status to ensure they followed the expected trends. Figures 3, 4, 5, 6 and 7 show the correlation between parameters and quality status. Species richness and the proportion of opportunists and Rhodophyta show a distinct trend with subjective increases in quality status, however, the proportions of Chlorophyta and the ESG ratio are less defined with less distinct boundaries between the good and moderate status. This is the most significant boundary as this distinguishes between an acceptable and unacceptable level of quality requiring mitigation according to the WFD. Further statistical analyses were run on the results to establish a level of significant difference between quality status groups.
Page 1 and 2: Water Framework Directive Marine Pl
Page 3 and 4: dates will result in a larger speci
Page 5 and 6: Figure 2: Sites included within the
Page 7 and 8: fauna and flora and exposed shores
Page 9: Table 1: Field sampling sheet to re
Page 13 and 14: All datasets were tested for normal
Page 15 and 16: Table 3: Calculation of ‘deshor
Page 17 and 18: Development of a Reduced Species Li
Page 19 and 20: certain species are only present on
Page 21 and 22: Figure 11: Map of the UK and Republ
Page 23 and 24: Table 4: Species lists for each of
Page 25 and 26: Table 6: Boundaries values for RSL,
Page 27 and 28: The final metric system works on a
Page 29 and 30: Table 10: Final quality status and
Page 31 and 32: EQR Value EQR Value 1.00 0.80 0.60
Page 33 and 34: EQR Value 1.00 0.80 0.60 0.40 0.20

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