Do Lab Manual For Harmful Algal Blooms
Harmful Algal Blooms (HABs)
Human Activities Affect Nutrient Cycles:
The human population is disrupting chemical cycles throughout the biosphere
Adding nutrients to the environment
Or removing nutrients from one part of the biosphere and then adding them to another
Effects can be positive or negative
Critical Load:
The amount of added nutrient that can be absorbed without damaging the system
In some cases, the addition of nutrients to ecosystems by human activity is beneficial, but in others it can cause problems.
The Key issue is the critical load…
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Eutrophication:
The enrichment of an ecosystem with nutrients
Excessive nutrients
Accelerated eutrophication of lakes
Nitrogen and Phosphorus run off into and overload streams
This reduces O2 , decreases aquatic plants, and increases algal blooms
This can eliminate other species because it is difficult for them to live in these new conditions
What Are Algae?
Also known as pond scum, seaweeds, phytoplankton, etc.
Range from small single-celled forms to complex multi-cellular forms
Can be prokaryotes (bacteria) or eukaryotes (protists, plants, you)
Are the primary producers (base of the food chain) in aquatic systems
Carry out photosynthesis most produce oxygen
Found in many places: fresh water, salt water, hot springs, snow, ice, and soil
Algal Blooms Decrease Light Penetration into the Water Column:
Algae
Aquatic Plants
As algae build up on the surface, they reduce and change the color of sunlight penetrating the water.
You can see here as nutrients are added, algae increase and the light changes from blue to green.
This makes it harder for aquatic plants to absorb the light and they are thus reduced as algae increase on the surface.
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Harmful Algal Blooms are Increasing Worldwide:
Lake Taihu, China
Baltic Sea
Lake Winnipeg
Algal blooms aren’t limited to Lake Erie,
Algal blooms are increasing worldwide.
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Major Algae Groups in Lake Erie:
Diatoms
Greens
Blue-greens
(Cyanobacteria)
Coming back to Lake Erie,
There are three type of major algae groups that can be found in Lake Erie
Greens are the most nutritious for other organisms and are not toxic or harmful, though in large blooms they can be a nuisance
Diatoms are the second most desirable, but they have a thick cell walls making them harder to break down
Blue-greens are known as cyanobacteria-these will only be consumed in desperation because they can produce harmful toxins
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Common Harmful Algae in Lake Erie (all are cyanobacteria)
Anabaena
Aphanizomenon
Microcystis
Lyngbya
There are several types of harmful algae in lake erie
The one you are recently most familiar with is the microsystis
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Microcystis aeruginosa:
A cyanobacteria (blue-green algae) species
Floats and forms a surface scum
Produces the toxin: microcystin
Potent liver toxin by several species
Causes rashes, abdominal pain, nausea, and potential death
Leads to beach closures and drinking water advisories
Can cause “fish kills”, death of farm animals, etc.
Microcystin chemical structure:
The chemical structure of microcystin is actually very similar to the structure of food coloring,
So you will use food coloring later today to simulate microcystin in the water
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Microcystis Bloom in Lake Erie:
This is what a microcystin bloom looks like in Lake Erie
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Microcystis bloom: The mouth of Maumee River, Lake Erie
The top images are satellite photos comparing a bloom in 2002 to one year later
You can actually see the algae from space!
Below are computer modeled graphs of turbidty which is the cloudiness or haziness of a fluid
caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air.
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Toledo Water Crisis: August 2014
Treated Toledo water exceeded the 1.0ug/L algal toxin limit recommended by the World Health Organization
“Do not drink” advisory Aug. 2-4
500,000 residents temporarily without potable water
Lake Erie Water Intake
Cyanobacteria Blooms:
Late summer is cyanobacteria season they like it warm
A warmer lake means more cyanobacteria
Here you can see that the blue green algae, which are cyanobacteria, become more abundant in the warm summer months
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2014 Algae Bloom Satellite Image:
Toledo Water Intake
Usually a bloom will be small or it will be blown out of the western basin quickly,
But in 2014 a perfect storm for microcysin brewed. It was HOT that summer and winds trapped the massive bloom along the southern shore, surrounding the Toledo Water Intake
For scale, remember you are looking at this bloom from space
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What is the Cause of Recent Algal Blooms?
The return of harmful algal blooms matches…
..the return of high phosphorus input to the lake
Agricultural Practices Increased Phosphorus Runoff
Tillage, fertilizer application method, timing, drainage control, soil testing, and much more…
Just read title
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Conclusions From Computer Models:
The increase in dissolved phosphorus loading since mid-1990s can largely be explained by:
Increased springtime storm intensity and frequency
Agricultural practices that decrease the land’s ability to retain applied dissolved P during heavy precipitation
Now I have a short video to show you fromthe National Center for Water Quality Research at Heidelberg University [Switch HDMI]
Explaining how 40 years of data points to dissolved reactive phosphorus as the primary culprit behind Lake Erie’s harmful algal outbreaks
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Conclusions:
Harmful Algal Blooms (HABs) are not a lake problem
They are a watershed problem
Caused by excess fertilizer input into the lake from human activities
Global warming will increase water temperatures, precipitation, & storm intensity favor HABs
When we find a solution to the fertilizer problem, Lake Erie will recover very quickly
Let’s get back to this!
So to summarize: SLIDE
Unlike legacy contaminants such as hg, PCB, and so on, phosphorus, algal blooms, and algal toxins will not hang around for decades.
So let’s jump into the lab now, you will follow the procedure in your lab packets and explore algae and water filtration.
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Dissolved Reactive Phosphorus Load
0
100
200
300
400
500
600
700
800
900
1 9 7 5
1 9 7 6
1 9 7 7
1 9 7 8
1 9 7 9
1 9 8 0
1 9 8 1
1 9 8 2
1 9 8 3
1 9 8 4
1 9 8 5
1 9 8 6
1 9 8 7
1 9 8 8
1 9 8 9
1 9 9 0
1 9 9 1
1 9 9 2
1 9 9 3
1 9 9 4
1 9 9 5
1 9 9 6
1 9 9 7
1 9 9 8
1 9 9 9
2 0 0 0
2 0 0 1
2 0 0 2
2 0 0 3
2 0 0 4
2 0 0 5
2 0 0 6
2 0 0 7
2 0 0 8
2 0 0 9
2 0 1 0
2 0 1 1
2 0 1 2
M e g
a g
r a m
s o
r M
e t r ic
T o
n s
Dissolved Reactive Phosphorus Load
0
100
200
300
400
500
600
700
800
900
1
9
7
5
1
9
7
6
1
9
7
7
1
9
7
8
1
9
7
9
1
9
8
0
1
9
8
1
1
9
8
2
1
9
8
3
1
9
8
4
1
9
8
5
1
9
8
6
1
9
8
7
1
9
8
8
1
9
8
9
1
9
9
0
1
9
9
1
1
9
9
2
1
9
9
3
1
9
9
4
1
9
9
5
1
9
9
6
1
9
9
7
1
9
9
8
1
9
9
9
2
0
0
0
2
0
0
1
2
0
0
2
2
0
0
3
2
0
0
4
2
0
0
5
2
0
0
6
2
0
0
7
2
0
0
8
2
0
0
9
2
0
1
0
2
0
1
1
2
0
1
2
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