Algae Biomonitoring: when

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1 Algae Biomonitoring: when inverts are not enough Cheryl Goncalves

2 Algae Bioassessment Protocols Worldwide there are many agencies using algae and diatoms to assess water quality in streams and lakes. US EPA -National Water Quality and Assessment Program (NAWQA) New Zealand Ministry of the Environment -Stream Periphyton Monitoring Protocol European Union- mandatory under European Water Directive

3 What are algae? Algae are aquatic photosynthetic organisms (unicellular or multicellular) that lack true roots, stems and leaves. Usually green and have chlorophyll

4 What is a diatom? Diatoms are microscopic unicellular colonial algae that have cell walls made of silica Size 2-200μm μ Yellowish brown photosynthetic pigment called fucoxanthin 100,000 species of diatoms Brown, slippery coating on submerged stones and sticks

5 Why are diatoms important? Primary producer Food source for benthic invertebrates and fish Provide an early warning of changing environmental conditions which may not be detected by other methods. Did you know Up to 70% of water quality changes will be reflected in diatom assemblages!

6 Benefits of Monitoring with Diatoms Rapid response to water Water chemistry: point in quality changes time Tolerances and Invertebrates: seasonal sensitivities are well Diatoms: 6 weeks to 2 known months Found in all stream environments Easy to sample and identify Inexpensive Teamwork! Diatoms are more sensitive to nitrogen and phosphorus; invertebrates are more sensitive to oxygen depletion and changes in temperatures. Sample both for a complete picture!

7 Development of the Algae Bioassessment Protocol In 2002 the University of Toronto and TRCA formed a partnership. TRCA staff collected algae samples at 150 stream monitoring sites. These algae samples were used by PhD student t Natasa Drakulic, to develop and produce (in partnership with MOE): 1. Algae Biomonitoring Protocol 2. Two diatom- based indices to evaluate water quality in Toronto streams. Toronto Region Saprobic Index (TR-SI) Toronto Region Trophic Index (TR-TI)

8 Fall 2008 Comparison Study TRCA and the Ontario Ministry of the Environment (MOE) formed a partnership to field-test and refine the Algae Bioassessment Protocol. In September 2008 a comparative study was conducted to: test the repeatability of the protocol identify areas where clarification or changes were needed

9 Site Selection Site Selection Criteria: i TRCA sites where diatoms were collected previously PWQMN sites with current/recent monthly water quality data

10 Field sampling Sites were defined following OSAP Site Identification criteria 2 crews Each site was sampled independently d by both crews on the same day 5 transects in riffle areas 5 observations across each transect

11 Algae Sample Collection Order of substrate preference: 1. rock 2. sand/silt 3. wood 4. macrophytes A Hydrolab or YSI was used to measure in situ water quality. Samples were composited and preserved in Lugols

12 Algae Sample Collection What exactly are we looking for? Not this! THIS!!!

13 Diatom Identification Count and identify 400 diatom valves for each sample Using Motic B5 series microscope equipped with phase contrast Identification to species level.

14 Diatom Morphology Epivalve Stria Girdle bands Raphe Hypovalve Diatom identification to the species level is based on the morphology of the siliceous wall (frustule). Acid digestion of the internal contents before slide preparation allows a clear view of the defining structures.

15 Data Analysis If the ABP protocol is repeatable, then different crews should obtain similar observations and data. Null Hypothesis: On average, there is no difference in data collected by separate field crews. Look at: Observations (field data) Species presence/absence Diatom assemblages Test for differences in TR-SI and TR-TI

16 Statistical Analysis Paired comparison of the 2 crews 1. By species 2. By diatom indices Trophic Diatom Index (TDI-TR) Generic Diatom Index (GDI) % Attachment method (Stalked, Prostrate, Erect, Unattached) % in each genus (% Achnanthes, % Cymbella, % Navicula, % Nitzschia etc.)

17 Student s ttest % Achnanthidium minutissimum Trophic Diatom Index (TDI-TR) Cosmopolitan species Calibrated for Toronto Provides an indication Region of when the last scouring event occurred Each Pair Student's t 0.05 Each Pair Student's t 0.05

18 Results of Student t test 96.7% of species comparisons showed no difference between sampling crews (p > 0.05) Species Comparison No difference Statistically different All of the diatom indices showed no difference between sampling crews. If results are NOT statistically different, can we assume that the protocol is repeatable?

19 ABP Workshop In April 2009 TRCA and MOE held an Algae Bioassessment Protocol workshop Goals: To educate practitioners about the value of algae and diatom monitoring To interest practitioners in joining the Partnership Study and testing the ABP in their jurisdiction Refine the ABP through the feedback of knowledgeable leaders in stream monitoring.

20 2009 Partnership Study Participants Credit Valley Conservation Ausable Bayfield CA Saugeen Valley CA Nottawasaga Valley CA Upper Thames CA Cataraqui Creek CA Site Selection Criteria Current monthly water quality sampling Benthic invertebrates collected in 2009 More urban sites Two impact sites (CVC and NVCA)

21 2009 Partnership Study Sites

22 Recommendations from Partners Time to implement protocol *Need to keep the sampling time under 15 minutes* Visual Assessment Subjective and not repeatable Make Visual Assessment optional Take photos of rocks you Sample Collection will be observe so everyone can the main focus agree on the description.

23 When to use the ABP? Areas where impacts are suspected (before costly water chemistry analysis) Impact assessments Did you know? Pre and post monitoring Diatoms can tell us what Routine monitoring the water quality was like in dried up stream beds! *Helps to guide water chemistry analysis to areas where it would be most useful.*

24 Next Steps 1. Incorporate recommendations of partner CAs into updated version of Algae Bioassessment Protocol. 2. Report diatom data and analysis back to partner CAs What diatom community tells us about average water quality Comparison between what diatom community tells us and chemical water quality data

25 Future Collaborations The ABP was designed to work with other comprehensive biomonitoring protocols such as: Ontario Stream Assessment Protocol (OSAP) Ontario Benthos Biomonitoring Network (OBBN) Data collected with the Algae Bioassessment Protocol will be shared with Isabelle Lavoie to test her IDEC index.

26 Questions? For further information: Please contact me at (416) ext 5766 or via