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GR-PP-LA [id:]

Method: Greek Assessment System for Reservoirs and Lakes Phytoplankton [Greek Assessment System for Reservoirs and Lakes Phytoplankton]

1. General information

1.01 GIG: Mediterranean
Relevant intercalibration types: Reservoirs: Siliceous and shallow calcareous lakes
1.02 Category: Lakes
1.03 BQE: Phytoplankton
1.04 Country: Greece
1.05 Specification: Lakes and reservoirs
1.06 Method name: Greek Assessment System for Reservoirs and Lakes Phytoplankton
1.07 Original name: Greek Assessment System for Reservoirs and Lakes Phytoplankton
1.08 Status: Method is/will be used in n.a.
1.09 Detected pressure(s):
Eutrophication Specification of pressure-impact-relationship:
Tested during Med GIG Phytoplankton IC exercise (based on the common dataset)
Yes, with quantitative data (e.g. against range of sites reflecting continuous gradient of pressure).
1.10 Internet reference: n.a.
1.11 Pertinent literature of mandatory character: n.a.
1.12 Scientific literature: n.a.
1.13 Method developed by: n.a.
Email of developer: n.a.
Institute of developer: n.a.
1.14 Method reported by: Vasiliki Tsiaoussi
Email of person reporting the method: n.a.
Email of institute reporting the method: Greek Biotope/Wetland Centre
1.15 Comments: none

2. Data acquisition

Field sampling/surveying

2.01 Sampling/Survey guidelines: n.a.
2.02 Short description: Integrated euphotic zone
2.03 Method to select the sampling/survey site or area: Stratified sampling/surveying
2.04 Sampling/survey device: Water sampler
2.05 Specification: none
2.06 Sampled/surveyed habitat:
Specification of sampled habitat: The euphotic zone in the deepest site
Sampled habitat: Single habitat(s)
2.07 Sampled/surveyed zones in areas with tidal influence: not relevant
2.08 Sampling/survey month(s): May/June to October
2.09 Number of sampling/survey occasions (in time) to classify site or area: 2 samplings in period May-October
2.10 Number of spatial replicates per sampling/survey occasion to classify site or area: n.a.
2.11 Total sampled/surveyed area or volume or total sampling duration to classify site or area:
Integrated euphotic zone

Sample processing

2.12 Minimum size of organisms sampled and processed: 1-2 micrometers
2.13 Sample treatment:
According to Utermöhl method (CEN Standard EN15204:2006). n.a.
2.14 Level of taxonomical identification:
Level: Species/species groups
Specification of level of determination: Species whenever possible
2.15 Record of abundance:
Determination of abundance: Individual counts
Abundance is related to: Volume
Unit of the record of abundance: mm3/l
2.16 Quantification of biomass: Utermöl technique
2.17 Other biological data:
2.18 Special cases, exceptions, additions: none
2.19 Comments: none

3. Data evaluation


3.01 List of biological metrics:
Phytoplankton biovolume; % of Cyanobacteria; Q index (based on functional groups of phytoplankton, Padisak (2006) with modification of F factors)
3.02 Does the metric selection differ between types of water bodies: n.a.
3.03 Combination rule for multi-metrics: Average metric score
3.04 From which biological data are the metrics calculated:
List of biological metrics: Data from single sampling/survey occasion in time

Reference conditions

3.05 Scope of reference conditions: Surface water type-specific
3.06 Key source(s) to derive reference conditions:
Scope of reference conditions: Existing near-natural reference sites
3.07 Reference site characterisation:
Number of sites: 1 site - Tavropos reservoir
Geographical coverage: Greece, only reservoir
Location of sites: Tavropos reservoir
Data time period: n.a.
Criteria: n.a.
3.08 Reference community description: n.a.
3.09 Results expressed as EQR: n.a.

Boundary setting

3.10 Setting of ecological status boundaries: Boundaries taken over from the intercalibration exercise
3.11 Boundary setting procedure:
The approach adopted by the L-M GIG was to set the G/M boundary value as a percentile of the distribution of the data collected for each index, namely 95th percentile for the biomass metrics and 90th percentile for the composition metrics. This assumption is based on the fact that nearly all the reservoirs sampled for the IC exercise were those firstly proposed for the IC site register, as a preliminary required step in the IC process. It is to be remembered that according to WFD Annex V.1.4.1, this site register is intended to form the IC network, representing the high/good and good/moderate class boundaries. The G/M boundary values of the four biological indices were calculated for each type: Siliceous Wet and Calcareous.
A validation of these results was made with data of Spanish reservoirs along the whole gradient of pressures and to identify the behaviour of some groups of algae in relation to eutrophication process. This approach allows analyzing whether the narrow range of G/M boundary values according to the IC sites corresponds with the changes in taxonomic composition as described in the conceptual model of the WFD normative definitions.
3.12 "Good status" community: n.a.


3.13 Consideration of uncertainty: n.a.
Specification of uncertainty consideration: n.a.
3.14 Comments: none

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Online: [date: 2021/09/24]
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