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Bluegreen Algae, Cyanobacteria

Hey I’m no expert on cyanobacteria, but exploring nature, peeping through microscopes, and teaching botany, they crop up.   Having the amazing ability to type words into Google and to read the results makes me a qualified Internet pundit! I self-declare a Ph.D. in cyanobacteriology.

Pundits love to define terms.   Algae and so-called bluegreen “algae” are a point of vocabularial confusion apparently beyond the comprehension of newscasters.   A complicating factor is that “algae” is a tough term to define, more descriptive of a lifestyle than of biological relationship.   A grab bag of simply constructed non-flowering water-dwellers. That is a license to use a term loosely.   Yet there is another way to see it.  Bacteria are more crisply defined.  Bacteria (and Archaea) are profoundly different from all other living things, right down to their basic biochemistry.   For vocabulary lovers they are prokaryotes as opposed to the eukaryotic algae. The bluegreen “algae” are bacteria, cyanobacteria.

algae mat in canal

Cyanobacteria crop up in disparate contexts:

  1. As symbionts, the main “botany classroom” role. Cyanobacteria are “good guys” as the right species in the right roles. Many cycads have “coralloid roots” poking aboveground looking pathological but actually inhabited by beneficial, symbiotic, photosynthetic, nitrogen-fixing cyanobacteria.   (Nitrogen-fixers convert atmospheric nitrogen to “fertilizer.”)  If you bust apart the floating fern Azolla…lots in South Florida…it has cyanobacteria folded into its leaves, making it a rice paddy fertilizer.  Cyanobacteria can inhabit the traps of carnivorous bladderworts and turn up inside hollow-water-holding cells in sphagnum moss.   The “alga” in some (cyano)lichens can be a cyanobacterium.
  2. Nitrogen-fixing cyanobacteria living freely, or perhaps not completely free, in the dirt and in hydric soils bring nitrogen to the earth.   During wet weather, great green globs of cyanobacteria jelly rise into prominence on the soil surface.
  3. On wet surfaces. Sometimes before I powerwash the patio, it is interesting to scrape the stains and see under the microscope who it is:   fungus?  green alga?  cyanobacteria?   Often the last-mentioned looking like dark pain on concrete and stones.
  4. In canals, lakes, and rivers. Summer in Florida, and “algae” in the news again! True algae, cyanobacteria, aquatic weeds, associated microbes and creatures, red tides, and dead zones are all part of the evil syndrome relating to our over-fertilized, over-nutrient-enriched, over-hyped Florida active adult lifestyle.   We’re a wet state, not that these problems are unique to Florida, and natural aquatic systems did not evolve dealing with all the nitrogen, phosphorus, and other nutrients humanity puts in the water.   Natural ecosystems evolved in a balance with “normal” nutrient levels, and when the levels skyrocket, some lifeforms suffer, while others benefit to the point of trouble.

 

Nostoc far

Rising from the wet earth

 

Nostoc microscope

Same as above, microscope view.

A windowsill experiment to see this is to put pondwater in four soda bottles.  In one bottle put no fertilizer,  and then increasing amounts in all the others.  One drop in one, two drops in the next, and so forth.   Wait a month.  A harmful algal bloom right before your eyes!

eutrophication - Copy

How many sources of nutrient enrichment can you think of?  Organic decay, sewage, septic systems,  manure,  biosolids,  fertilizers.  Twenty-some million Floridians and tourists generate oodles of sewage.  Treatment does not remove all the nutrients, even passage through artificial wetlands.    One way to shed nutrient-loaded sewage treatment water is as reclaimed irrigation water,  inviting turf and ornamentals to take up the nutrients,  and those nutrients are back into the ecosystem.

Agriculture comes up in the news about the polluted Lake Okeechobee system:  manure, fertilizers, backpumping.   And then there are biosolids, treated sewage sludge spread onto the earth.

As anyone who watches the news would know, releasing nutrient-enriched waters from Lake Okeechobee  causes unwanted aquatic life where the water goes: unnatural weed infestations in the Everglades and harmful algal/cyanobacterial blooms along the rivers draining the lake, extending into the sea.  That unwanted growth, especially the cyanobacteria “algae,” make dangerous toxins.

There are plenty of targets for the finger of blame, and authorities from whom to demand action.   No need to repeat the usual list of suspects.  I would not want to be any of them, because cures are not obvious, nor without downsides, and as Pogo croaks from the polluted swamp, the enemy is us.  Florida was never meant to host a gazillion people.

concrete by wall

Many stains on rocks and concrete are cyanobacteria.

Which sources of trouble can we control?   Ample room for argument, but most controls will be tweaks, details, adjustments, NIMBY, and redirections.   How do you diminish sewage nutrients, agriculture, and too much rain in Lake Okeechobee (restore more natural outflow?)?    Curtail Florida development?   Heresy!    Seems to many observers, and recall my amateur status with no data, one actionable point might be limiting residential fertilizer applications, which might mean we don’t all need a big sprawling St. Augustine lawn.

Canal with algae

Cyano-soup

It isn’t just the Lake Okeechobee system of course.   This summer the eutrophic canals and ponds suddenly have smelly floating mats of green.       Close examination of a floating mat is eye-opening.   Tried it yesterday in a stagnant canal in Jupiter, speaking over over-development.

Algae mat microscope

The mat from canal yesterday, dominated by Cyanobacteria (the striated filaments).

The mat is a tapestry dominated by filamentous cyanobacteria (marked by their cross-striations) interwoven with filamentous algae, varied single-celled algae and alga-like organisms, wriggling animalcules, and decaying globs of organic matter.    Those decaying globs sink, stink, and take up oxygen as they go.

CLICK for a 40 second flyover.

One of the abundant filamentous ones is called Oscillatoria.  It wiggles like some sort of mud-dwelling worm.  CLICK to see the wiggle (about 40 seconds).

This may be an artifact of my limited experience, but that experience so far finds unicellular (sometimes clinging into clusters) cyanobacteria in the St. Lucie River, with the filamentous types (strings of rectangular or circular cells) in the floating mats on canals.

 
 

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Witch’s Butter

Nostoc commune:  icky gross slime, or emerald carpet?

Cyanobacteria

(Note—the term “witch’s butter” is applied also to other slimy things, mostly fungi.  It is not exclusive to today’s cyanobacterium.)

Today John, George, and the Florida Association of Environmental Professionals Treasure Coast Chapter combed the wet regions of Jonathan Dickinson State Park for grassy plants.  About a million species to enjoy.  The pine woods vistas and wildflowers were gripping as always. Blue Curls were at their best.

Blue Curls by John Bradford.

Blue Curls by John Bradford.

Now look on the ground below that fetching wildflower, there’s something even better.  What grabbed me with the most gusto today were waves of green jello on the otherwise bare scrubby soil.  We’re talking about huge bacterial colonies of the  blue green bacterium (cyanobacterium) Nostoc commune.   Some observers erroneously call these blue-green “algae.”  And some get upset when the “algae” befoul their pristine lawn of pride.

Nostoc (by GR, John is drawn to beauty, but I like the lowdown and slimy)

Nostoc (by GR, John is drawn to beauty, but I like the lowdown and slimy)

This is one mighty germ.  It is photosynthetic growing in microscopic strings of cells in colonies as big as dinnerplates.  This species fixes nitrogen in special air-tight cells called heterocysts, seen as the larger light-colored cells in this photo link microscope view.

When you transform atmospheric nitrogen gas into forms plants can use, that’s fixed nitrogen.  Legumes and some other plants do it with the assistance of certain bacteria.   The symbiotic bacterial helpers in some cases, such as in Cycads, are species of NostocNostoc is the “algal” partner in some lichens as well, but today you have Nostoc living proudly off the leash.  If this nitrogen-fixing mat isn’t nitrogenizing the hungry scrub sand I’ll be a monkey’s uncle!

Nostoc in JD Park

Nostoc in JD Park

You could walk through the scrub for years in dry weather and never spy Nostoc, except maybe as an inconspicuous dry crust we crush while seeking interesting things.  This organism can dry out to a mere nothing for months, probably many years, and eventually bust out into its idea of glory when wet and ready.  Then dry times resume and bye bye for now.

The world is full of odd symbioses, and Nostocs (including today’s species? perhaps not) have an unusual relationship with a tiny midge prone to lay its eggs in the Nostoc jelly for a safe haven and nourishment.  What the fly offers the Nostoc is odd, if not adequately studied:  the larva seems to induce changes in colony shape with an enhanced grip on its substrate and probable enhanced photosynthetic production.  If I had nothing else to do, I could happily spend tomorrow searching for the larvae before the present Nostoc patches go back into hiding.  Want to go play golf tomorrow?  No thanks, I’d rather look for maggots in bacterial slime blobs.

Nostoc commune and related species are global and like arid places.  They tolerate blistering heat, arctic freezing, blazing sun, and extended drought.  No surprise they prompt research to probe the molecular biology behind happy life in extreme environments.   Nostocs make so much fatty gel they’ve raised the eyebrows of biofuelophiles.  They are so responsive to wet-dry cycles they cause research on environmental gene control.   Nostoc reacts to extreme sun exposure with a UV-screen not known in any other living thing.

That UV protection is perhaps linked to an example of why we don’t eat the weeds, even if other people do.  A recent article in the Journal of Ethnophamacology  described the traditional consumption of Nostoc commune in Peru.  Yummy good–but the fly in the ointment is a neurotoxic amino acid possibly linked to neurodegenerative disease.  There’s always something.

Maybe it is no surprise how these close relatives of the oldest fossils known on earth survive nasty conditions perhaps resembling the primitive Earth when cyanobacteria ruled.  Back when we were an almost-uninhabited planet.  Like Mars.

Hmmmm, too bad Mars is so dry these days.  Maybe a little green Martian Nostoc would come forth with a good honest wetting.

Mars Rover footprint, or John's tripod print?  You decide.

Mars Rover footprint, or John’s tripod print? You decide.

 
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Posted by on September 27, 2014 in Nostoc commune

 

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