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The sampling and preparation of algae. Maria Kahlert. Sampling of diatoms. Different approaches: Most common: Use of benthic diatoms for routine monitoring of streams
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The sampling and preparation of algae Maria Kahlert
Sampling of diatoms • Different approaches: • Most common: Use of benthic diatoms for routine monitoring of streams • EU standard for sampling:EN 13946 (2003). Water quality - Guidance standard for the routine sampling and pretreatment of benthic diatoms from rivers • National standards for the bioindices and class boundaries • Use of diatoms for lakes under way
Sampling of other algae • Investigation of the total benthic algal community • Approach to EU standardize even non-diatom sampling to reach all goals of the WFD 00230228 prEN 15708 Water quality - Guidance standard for the surveying, sampling and laboratory analysis of phytobenthos in shallow running water. Under Approval 2009-05 • Nordic standard (Jarlman, Lindstrøm, Eloranta & Bengtsson 1996) • National methods (check for example the Austrian, German and Norwegian methods)
Sampling of other algae • Different approaches: • Quantitative sampling • hard substrate: brush samplers (e.g. Peters et al. 2005) • macrophytes: copy of macrophytes, image analysing (e.g. Kahlert 2000), sampling in tubes • Transect methods • estimation of percentage cover within a frame (e.g. NO) • By eye • With camera and picture analysis • Semi-quantitative (e.g. Nordic standard)
Sampling of all algae Nordic standard – analysis of macroscopic and microscopic communities • Macroscopic communities: • Screening of river bed, estimation of percentage cover of different communities by eye, qualitative sampling of all different communities, verification in laboratory • Percentage cover: • < 5% • 5-10% • 10-20% • 20-50% • 50-100%
Sampling of all algae Nordic standard – analysis of macroscopic and microscopic communities • Microscopic communities: • Qualitative sampling of stones if present, otherwise other dominating substrates, analysis in laboratory • Semiquantitative estimation: • 1 = rare occurrence • 2 = moderate occurrence • 3 = common occurrence • 4 = abundant occurrence • 5 = very abundant occurrence
Sampling of all algae • Investigation of the total benthic algal community Idea: to know the whole community and biomass will give a better picture of the ecological status of a stream or lake than only an analysis of the relative abundance of diatoms. For example, grazers are dependent on a certain biomass and algal composition to survive.
Sampling of all algae • Investigation of the total benthic algal community • However, this analysis is very time consuming, extremely difficult to standardize, and has a high error when used for biomonitoring • With time, there will be more experience, even methods and indices will get better probably with an increased use
The preparation of algae • Diatoms: Detailed method (A. Jarlman) following EU standard: EN 14407 (2005). Water quality - Guidance standard for the identification, enumeration and interpretation of benthic diatom samples from running waters • Soft algae: Modified method following R.J. Stevenson (1984)
References EN 13946 (2003). Water quality - Guidance standard for the routine sampling and pretreatment of benthic diatoms from rivers EN 14407 (2005). Water quality - Guidance standard for the identification, enumeration and interpretation of benthic diatom samples from running waters 00230228 prEN 15708 Water quality - Guidance standard for the surveying, sampling and laboratory analysis of phytobenthos in shallow running water. Under Approval 2009-05 Jarlman, A., Lindstrøm, E.-A., Eloranta, P. & Bengtsson, R. (1996). Nordic standard for assessment of environmental quality in running water. In: Whitton, B.A. & Rott, E. (eds), Use of algae for monitoring rivers II, p. 17-28. Kahlert, M. & Pettersson, K. (2002): The impact of substrate and lake trophy on the biomass and nutrient status of benthic algae. – Hydrobiologia 489: 161-169. Peters, L., Schleifhacken, N., Kahlert, M. & Rothaupt, K.-O. (2005): An efficient in situ method for sampling periphyton in lakes and streams. – Arch. Hydrobiol. 163 (1): 133-141. Stevenson, R.J. 1984: Procedures for mounting algae in syrup medium. Transactions of the American Microscopical Society 103:320-321.