Annex A.

Table A1. NGIG methods of sampling and analyses of phytoplankton composition:

Methods / General NGIG / FI / SE / NO / UK / IE
Time period of sampling / May-Sept
For % Cyano:
We only used data from July-Sept / May-Sept (Oct) / May-Sept (Oct) / May-Sept (Oct) / March-Oct (?) / April-Oct (?)
Sampling frequency / 1-6 times/y, most sites sampled in late summer (July/Aug) / 1-2 times/y for most sites / 1-2 times/y for most sites / 4-6 times/y for most sites / ?? / ??
Sampling depth / 0-2 m for most sites (??) (depends on answers from SE, UK and IE) / 0-2 m integrated / ? / 0-6 m integrated, or less in shallower lakes / ? / ?
Lab methods for phytoplankton compostion / Utermöhl technique: Cell counts for each taxon converted to biomass using geometric figures. Nordic standard applied in FI, SE and NO, but not in UK and IE. Details on how to count and estimate biomass for colonial Cyanobacteria is not standardized and may cause a lot of uncertainty. / Utermöhl technique: Cell counts for each taxon converted to biomass using geometric figures. Nordic standard applied. Filamentous taxa (Planktotrix, Aphanizomenon etc.) are counted in units of mm, and converted to biomass by multiplying with the area of the cross-section of the filaments. For globular colonies (Microcystis, Anabaena etc.) the number single cells are estimated, and converted to biomass by multiplying with estimated volume of a single cell.
Quality assurance / FI, SE and NO have intercalibrated their methods for analyses of phytoplankton composition for a number of years (at the level of single experts).
UK and IE have not participated in any methodological intercalibration and there is a lot of variation between different experts (??)

Annex B. National metrics for phytoplankton composition.

Sweden: (Eva,please fill in your national method here)

………………………………………..

UK. (Geoff, please fill in any info you can contribute now on the state of development of your national method)

……………………………………….

Annex C. Response curves of % Cyanobacteria in different NGIG types.

CLEARWATERLAKES: Moderate alkalinity, shallow

CLEARWATERLAKES: Low alkalinity (shallow and deep, lowland and boreal)

HUMIC LAKETYPES: Low alkalinity

Moderate alk. humic

Annex D. Boxplots of distributions of % Cyanobacteria for reference sites vs. impacted sites for Clearwater lakes and Humic lakes.

a) Clearwater lakes (LN1, LN2a, LN2b, LN5a)

Annex E. List of reference sites (which have data on phytoplankton composition) Robert: Can you please paste in the ref.sites we used in Helsinki here?

Annex F. Data underlying the analyses

Excel table (Robert, can you paste in these data please?)

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