What are cyanobacteria trying to tell us?

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What are cyanobacteria trying to tell us?

Charles Trick (cyano@uwo.ca) Professor, Department of Biology Western University, London, Canada Professor, Public Health Schulich School of Medicine and Dentistry


I Cyanobacteria

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Whole Package - Beautiful PROKARYOTIC bundles (photosynthesis, nutrient uptake, vitamin use, communication, …) Physiology - transformed the Earth - created the O2-rich environment that we have today. Biochemistry – ancient and modern. Biogeochemistry – produce 20% of our atmospheric O2. Biodiversity - Assist in soil recovery, corals, symbiosis. 3


I Cyanobacteria

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Special unique biochemicals.

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I Cyanobacteria

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Colorize a flamboyance of flamingos.

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When it comes to Muskoka lakes … I

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Cyanobacteria when the become HABs *

Esthetically poor. Smell, taste issues. Sign of a “blocked” ecosystem – energy through food chain, light to lake bottom, anoxia + fish kills. Home for unwanted human waste microbes.  quality of life  property values  family values

* HABs – Harmful Algal Blooms 6


When it comes to Muskoka lakes … I

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Cyanobacteria

Produce water-borne toxins that are hepatotoxic in lab rats.

Produce aerosolic compounds associated with brain & muscle maintenance (Amyotrophic lateral sclerosis, Alzheimer's)

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How to avoid Cyanobacterial HABS in Muskoka lakes ‌

G A P

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How to avoid Cyanobacterial HABS in Muskoka lakes ‌

H y p o t h e s i s

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How to avoid Cyanobacterial HABS in Muskoka lakes …

H y p o t h e s “Think like a cyanobacterium” i s 10


How to avoid Cyanobacterial HABS in Muskoka lakes …

G A P We must “Think like a cyanobacterium” 11


“Think like a cyanobacterium”

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“Think like a cyanobacterium” as told by a scientist …

We Wemust must“Think “Thinklike likeaacyanobacterium” cyanobacterium” 13


“Think like a cyanobacterium” H1: It’s all about P and N entering the lake. Cyanobacteria are BLOOM species. Bloom species are HIGH biomass To make biomass we need more building blocks Building blocks are C, N, P, Fe.

∴Lower N, P then no bloom.

https://scwrs.wordpress.com/2015/03/18/unlocking-lake-of-the-woods/

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“Think like a cyanobacterium” H1: It’s all about P and N entering the lake. Cyanobacteria are BLOOM species. Bloom species are HIGH biomass To make biomass we need more building blocks Building blocks are C, N, P, Fe.

∴Lower N, P then no bloom.

https://scwrs.wordpress.com/2015/03/18/unlocking-lake-of-the-woods/

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“Think like a cyanobacterium�

No longer strictly associated with eutrophication

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“Think like a cyanobacterium”

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“Think like a cyanobacterium” H2: There has been a shift from eukaryotic phytoplankton to cyanobacteria. Cyanobacteria are natural but non-dominant species. All the nutrients shift into cyanobacteria Since nothing eats cyanobacteria  cells accumulate

∴Trophic shift has occurred (non-cottage driven)

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“Think like a cyanobacterium” H2: There has been a shift from eukaryotic phytoplankton to cyanobacteria. Cyanobacteria are natural but non-dominant species. All the nutrients shift into cyanobacteria Since nothing eats cyanobacteria  cells accumulate

∴Trophic shift has occurred (non-cottage driven)

Anabaena 2 microns Divide 2 times per day

Prymnesium 40 microns Divide 1 time every 1.5 days

Asterionella 60 microns Divide 1 time every 3 days

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Nutrients Available

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Nutrients Available

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Nutrients Available

* Numerous small particles = many fewer large particles

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Sugar Available

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130 cookies 10 mins 4 cups Sugar Available

4 loaves 30 mins

1 cake 90 mins

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So why the shift from eukaryotes (good) to cyanobacteria (bad)? Is climate change driving cyanobacteria blooms to Muskoka or more remote lakes?


hydrological intensification

Data from Irena Creed, Western University

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hydrological intensification

More dry days interspersed between larger precipitation events. ✓Longer warming season - until November. ✓ Increased overland runoff – more nutrients in spring. ✓ Longer period where landscape/cottage seepage will maintain a population. ✓ Longer autumn period where cells will compete for disappearing nutrients. Data from Irena Creed, Western University

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Cottage pressure

Cottage pressure plus climate pressure

Threshold

Holling CS (1996) Engineering resilience versus ecological resilience. In: Engineering Within Ecological Constraints (ed. Schulze P), pp. 31–44. National Academy Press, Washington, DC.

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Need for a new paradigm? at least one other causal factor is linked to increasing productivity of cyanobacteria blooms

Phosphorus

Nitrogen Cyanobacterium Cell PO43-

Fe PO43-

NtR NO3-

Fe

NH4+

NH4+ Fe

Fe2+

Fe FeR

Iron Fe2+ Fe3+

N2

NiF

Is iron the “missing� factor linking productivity and cyanobacteria bloom formation? 32


Do cyanobacteria access Fe2+ from lake sediments? Eukaryotic Cell

Fe2+ [Fe3+]

[Fe3+]

Cyanobacterium Diffusion of Fe2+ from anoxic sediments (i.e., internal loading). Migration of cyanobacteria down into Fe2+-rich waters to access Fe2+ to meet their Fe needs.

[Fe2+]

Fe2+

Anoxia

lakes the hypolimnion remains aerobic – control the surface Fe+ 33


Do cyanobacteria access Fe2+ from lake sediments? Fe2+

[Fe3+]

Eukaryotic Cell

[Fe3+]

Cyanobacterium Diffusion of Fe2+ from anoxic sediments (i.e., internal loading). Migration of cyanobacteria down into Fe2+-rich waters to access Fe2+ to meet their Fe needs.

[Fe2+]

Anoxia

Fe2+

Add 8-hydroxyquinoline

Molot et al. 2010. Iron‐mediated suppression of bloom‐forming cyanobacteria by oxine in a eutrophic lake Freshwater Biology 55(5):1102 – 1117.

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Your nutrient contribution [C,N,P,Fe]

Esthetics

Maintain the catchment physical structure [nutrient capture, temperature, light, mixing]

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Eliminate extra organic material entering the lake (anoxia, nutrient recycling)

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CyanoHABs

Drinking water

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Human and ecosystem health (toxins)

Planktonic vs Benthic plants)

DRIVERS (PREVENTION ACTIVITIES)

CONSEQUENCES (MANAGEMENT)

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A wicked problem is a problem that is difficult or impossible to solve. A wicked problem is a problem that is difficult or impossible to solve because of incomplete, contradictory, and changing requirements that are often difficult to recognize. Just because a problem is wicked, it does not mean that no attempt should be made to solve it. In fact, it is the exact opposite. It is exactly what you are doing today. Environmental problems of this nature are social problems. Prevention and mitigation approaches are needed. Almost none are easy, quick or solitary. (If it was easy there would be no need for this meeting.) You are a very blessed community. You have a special place in the world to protect. And here, you have a tremendous level of expertise at your disposal. And you will achieve affective change from collaboration, conversation, actions and perseverance. 36


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Climate drivers Delay in leaf fall, even longer delay in runoff

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Microcystin – group of ~80 molecules Hepatotoxin (think … 3E) (liver damage enzymes) Microcystin in drinking water is 0.0015 mg/L (1.5 µg/L) suffered abdominal pain, nausea, vomiting, diarrhea, sore throat, dry cough, blistering at the mouth and headache. Microcystis sp. colony

Anabaena sp. filaments

Cylindrospermopsis

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Microcystis sp. colony

Anabaena sp. filaments

Cylindrospermopsis

Anatoxin-a – known as Very Fast Death Factor (VFDF), causes acute neurotoxicity when ingested. Results in loss of coordination, muscular fatigue and spasms, and respiratory paralysis. Binds to the acetylcholine receptors of the body. Lethal dose? No one knows. Estimate 5 – 10 mg/body. (i.e. lots!)

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Microcystis sp. colony

Anabaena sp. filaments

Cylindrospermopsin is a potent inhibitor of protein synthesis, an irritant, and causes skin damage/rash. “General� toxin causing damage to the kidneys, adrenal glands, small intestine, lungs, thymus, and heart. Lesson learned in Australia: killed off bloom with copper sulfate – 141 people to hospital over the following 5 days. Cylindrospermopsis

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