Writing my blog allows me to meet many interesting people. Recently, fellow Sewall’s Point resident, and active Vietnam Veterans of America member, Mr. Frank Tidikus, introduced me to Canadian and part-time Martin County resident, Professor Geoffrey Norris who is a geologist and algae fossil specialist with a long career at the University of Toronto.
Professor Norris, his wife, and I met at the Prawnbroker and had a lovely exchange. Dr Norris describes himself as such…
University of Toronto: http://www.es.utoronto.ca/people/faculty/norris-geof/
...In the 1960s, I lived and worked as a petroleum exploration geologist in Tulsa, Oklahoma. Subsequently, I spent almost 40 years at the University of Toronto in teaching and research in geology…A geologist by training, I have a specialized knowledge of fossil algae, their ecology, morphology, and distribution. I have published hundreds of scientific papers on fossil algae and related topics…
Professor Norris shared two papers composed for his property association at Indian River Plantation on Hutchinson Island along the Indian River Lagoon during the 2016 toxic algae extravaganza. Today, I will share the first entitled: “Blue-green algal blooms in the lakes, rivers, and marine waters of south Florida surrounding Lake Okeechobee.” His second, specifically on Sugarcane, I will provide next week.
Professor Norris’ summary and full paper is below. It is excellent in that it is able to relay complex subjects to the everyday reader interested in water quality and improving the plight of our St Lucie River/Indian River Lagoon.
What is most amazing to me are his comments on glyphosate, most famous for being the active ingredient in Roundup, but now used under many names. Sometimes I hear people screaming so much about Roundup that I tune it out, but Professor Norris’ observations really got to me.
He notes that glyphosate, used excessively in agriculture production around south and central Florida may actually “feed”cyanobacteria (toxic blue-green algae blooms). Also mind-blowing are Professor Norris’ insights into the reproduction of the hungry and ancient cyanobacteria that reproduces through binary fission (copying itself) “producing endless clones” “with no dissipation of mutant genes as a checks and balance to adaptation…”
Yikes! Really?
Jacqui
Executive Summary
- This report provides basic information on blue-green “algae” and explains that they are actually bacteria (cyanobacteria). These blue-green bacteria form blooms in Lake Okeechobee that in turn are released by the Army Corps of Engineers into canals and estuaries of south Florida.
- The blue-green bacteria grow by using sunlight as an energy source to synthesize elements from the water into more complex compounds used in their cells. When important nutrients such as phosphorus and nitrogen are present in excess, the bacteria multiply rapidly and accumulate as highly concentrated masses of cells, called blooms.
- Blue-green bacteria can synthesize nitrates from atmospheric nitrogen, but also need phosphorus dissolved in water to survive and thrive. If phosphorus is scarce in the water, this limits the growth of the bacteria. If it is abundant, blooms can be triggered.
- Run-off and back pumping into Lake Okeechobee from surrounding Everglades agricultural lands and upstream from the Kissimmee River watershed is suspected of providing a potential abundant source of phosphorus for blue-green bacteria, in phosphate-rich fertilizers and herbicides such as Roundup (glyphosate).
- Glyphosate (2-[(phosphonomethyl)amino]acetic acid) is of particular concern, since it has been used heavily in the agricultural areas around Lake Okeechobee and upstream in the Kissimmee River watershed for at least 25 years. Glyphosate provides a source of phosphorus for blue-green bacteria and recent research by others suggest that glyphosate enhances the growth of blue-green bacteria, which become tolerant and absorb glyphosate directly.
- The blue-green bacterial blooms released into the St Lucie Estuary (principally Microcystis) are formed in freshwater but appear to be tolerant of dilute salinities, and recent research suggests can build up resistance to increased salinities such as are found in estuarine waters.
Blue-green algal blooms in the lakes, rivers, and marine waters of south Florida surrounding Lake Okeechobee
By Geoffrey Norris Ph.D. FRSC
6 July 2016
Introduction
I am a property owner in Stuart, Florida and have been alarmed – along with many others – at the spread of blue-green algae (aka cyanobacteria) into the St Lucie River and adjacent areas by water releases from Lake Okeechobee. There has been much publicity and calls for action over the years but very little appears to have been done to solve this long-standing problem at any level of government, until very recently. Now, a State of Emergency has been declared by the Governor of Florida. Recent initiatives, following public meetings in Martin County thanks to the Board of County Commissioners, have been undertaken by Florida Representative Gayle Harrell and Senator Joe Negron and their colleagues in association with Senators Marco Rubio and Bill Nelson and Rep. Patrick Murphy to urge the Army Corps of Engineers to stop immediately the nutrient-laden discharges from Lake Okeechobee.
Although I am a property owner and tax payer in Martin County, I am also a Canadian snowbird and therefore do not have a vote, which is a little constraining when trying to influence political decisions. Therefore, I decided to put my energies into assessing what is known about the current situation of the blue-green blooms. I am a geologist by training and I do have a specialized knowledge in particular of fossil algae that have been extremely important in oil and gas exploration over the decades gone by. I am not a biologist but I do have some knowledge of the literature on algae – their ecology, morphology and distribution in various environments. I have published hundreds of scientific papers on fossil algae and related topics and hope that the following – largely based on biological and agricultural literature – will pass muster.
In the following presentation my aims are twofold:
Firstly, to try and answer commonly asked questions about blue green algae (which are actually bacteria) that might be helpful in clarifying some of the technicalities of a complex subject.
Secondly, to highlight what to my mind is the ultimate cause of the blue-green outbreak: that is, the heavy application of phosphate-bearing fertilizers and herbicides around Lake Okeechobee together with back pumping of agricultural run-off into the Lake. In particular I believe that the well-known weed killer glyphosate (e.g. Roundup) may be implicated as a major contributor to the problem. South Florida and somewhat later Central Florida became major users of Roundup in the early 1990s, long before its popularity spread north into the corn and bean belt.
Feel free to pass this article on to others. I would welcome comments by email at rosalex@interlog.com
What are blue-green algae?
Well, for starters they are not actually algae at all. They were discovered in the 19th century by biologists using newly invented high-powered microscopes. They noticed a variety of microorganisms living in water, some of them with green pigments in the cells that allowed photosynthesis to occur, similar to the well-known photosynthesis occurring in the much larger land plants and driven by chlorophyll. But they were much simpler in organization than the large land plants so were called “algae” (singular alga, from the Latin word for seaweed). Some of these microorganisms contain a rather different bluish pigment and were therefore referred to as “blue-green”, and in these early days were judged nevertheless to be algae – hence blue-green algae.
It was only later that biologists realized that the blue-green microorganisms were crucially different from algae because they had no nucleus in the cell and their pigment was not organized into a “blob” within the cell like most other algae. In the scientific literature they are now regarded as bacteria and the blue-greens are referred to as cyanobacteria – that is, photosynthetic bacteria that use a blue-green pigment to facilitate the use of the sun’s energy to produce organic compounds needed by these organisms.
It is important to understand this difference between the blue-green cyanobacteria on the one hand and the “true” algae on the other. I will come back to the difference between bacteria and algae later, and how this impacts on bloom formation.
Meanwhile, the term “blue-green algae” has gained traction in the news media and is now widely understood to be implicated in the blooms of microorganisms that occur from time to time in lakes and rivers in Florida and elsewhere. I will use either of the terms “blue-green algae” or “cyanobacteria” depending on the context, or just the neutral term “blue-greens”. But remember they are actually bacteria.
What are algal blooms?
An algal bloom is the result of rapid increase or accumulation of algae in a body of water. They can occur in freshwater (lakes, rivers) or in marine water (estuaries, lagoons, coastal embayments). Different types of algae (including the blue-green cyanobacteria) produce different blooms characterized by green, bluish, yellow, brown or red colors. The density of pigmented cells in a bloom is enormous, and measured in the hundreds of thousands to billions of cells per liter (1 liter is almost a quart) depending on the species.
Blooms can be quite localized and appear as a streak on the water or can be very large and visible from space, such as the algal blooms that occur from time to time in Lake Erie and measure tens to hundreds of miles in extent. The recent blue-green algal bloom in Lake Okeechobee was reported to be more than 30 square miles in extent.
What causes blooms?
Blooms occur naturally when the water contains an excess of nutrients such as phosphorus and other compounds. This causes an increase in the growth of algae leading to very high concentrations of cells that become visible as colored streaks and patches in the water. Other factors involved in triggering algal blooms include temperature changes, sunlight intensity, changes in water chemistry and changes in water currents.
What are the red tides that occur in Florida?
A red tide is just another name for a bloom of “true” algae in marine water, and in this case a particular algal group called dinoflagellates. Red tides can be red but more often occur as greenish or yellowish colored water in the coastal areas of Florida. The term “harmful algal bloom” is often preferred in referring to these dinoflagellate blooms that do indeed harm wildlife and human life in different ways e.g. toxic shellfish poisoning; respiratory illness; mass fish kills.
So what caused the blue-green algal blooms in Lake Okeechobee?
First, it is important to understand that blue green algae are uniquely different. Not only are they photosynthetic bacteria but they are also capable of manufacturing their own supply of nitrates from nitrogen in the atmosphere, one of their crucial nutritional requirements. So the blue-greens have plenty of nitrogen to live on but they also need other important elements and compounds to thrive. One of these is phosphorus, which often occurs naturally in water in trace amounts as phosphates. If phosphorus is scarce, then this limits the growth of the blue-greens even though they have potentially a lot of nitrates available. The amount of phosphorus available becomes a limiting factor for growth of the blue-green algae. If phosphorus becomes more abundant in the water, then the blue-green algae thrive and multiply until they become visible as a bloom. It is believed that high phosphorus concentrations in Lake Okeechobee are capable of triggering blue-green algal blooms.
So where did the phosphorus come from in Lake Okeechobee?
Lake Okeechobee is surrounded by agricultural land that is being intensively farmed. Run-off from the farmland appears to be entering Lake Okeechobee, and this includes various phosphate-rich fertilizers and herbicides such as Roundup (glyphosate).
But Lake Okeechobee water levels are higher than the surrounding plain. How can run-off into the Lake happen?
Well, firstly, Lake Okeechobee and the surrounding farmland share a common water table. Transfer of minerals and soluble organic compounds can occur through the groundwater. But probably more importantly, until recently it was common farming practice to back pump excess run-off water from the agricultural land into Lake Okeechobee. Almost certainly this had led to the accumulation of phosphorus and other nutrients in the Lake as well as unused agricultural chemicals. Aerial transmission into the Lake from crop dusting is also possible.
So now that back pumping has been discontinued will this solve the problem?
Not really, because although farmers now are not allowed to back pump into the Lake, the South Florida Water Management District has responsibility to alleviate the threat of flooding. They can – and do – back pump surface water from the surrounding land into Lake Okeechobee, if excessive rainfall conditions threaten to flood the communities around the Lake. Rainwater running off the agricultural land will still contain phosphorus and other compounds derived from fertilizers. Furthermore, from time to time the Army Corps of Engineers controls the level of Lake Okeechobee by releases of lake water into the canals, which in turn feed into the estuaries around Stuart and other coastal communities.
Are there any other agricultural products that are contributing to the appearance of blue-green algal blooms?
Yes, there is one in particular that is of great concern. Glyphosate is the active ingredient in the well-known weed killer Roundup. It is used intensively by farmers over much of North America. South Florida is one of the areas where it is being used very heavily in agriculture, and has been since at least 1992 (the earliest available data). A little further to the north, Central Florida’s usage of glyphosate surged in 1993 and continued until 2013 (the last available data) and may also be a source of glyphosate in Lake Okeechobee but originating further upstream in the Kissimmee River watershed and its interconnected lakes.
http://water.usgs.gov/nawqa/pnsp/usage/maps/show_map.php?year=2001&map=GLYPHOSATE&hilo=L
Why is glyphosate of such concern?
Glyphosate is an organic compound with phosphorus as an important component as well as nitrogen in its chemical make-up. It was invented by Monsanto chemists, brought to market in 1974, and its chemical name is N-(phosphonomethyl)glycine (aka 2-[(phosphonomethyl)amino]acetic acid) – glyphosate for short and much more easily remembered. Monsanto’s patent on glyphosate expired in 2000 and since then it has been manufactured by dozens of companies with a significant drop in price and therefore increasing popularity with farmers. In 2007 it became the most-used herbicide in agriculture in USA. It works as a weed killer by inhibiting the production of certain plant amino acids and enzymes. After it has done its deadly work, some of it can break down in the soil into simpler molecules of carbon, hydrogen, oxygen, nitrogen and phosphorus. Excess glyphosate can run off into water, particularly at peak farming times. Its use has been expanding in the agricultural sector by about 20% per year for the last several years.
So far, so good. It kills most green plants, if that is what you want. I personally use it to kill poison ivy on my property. Unfortunately, it has become apparent through a number of recent laboratory-based studies that glyphosate does not act as a killer for some blue-green algae, aka cyanobacteria. Firstly, the blue-greens love the phosphorus in glyphosate or its degradation products, which otherwise is a limiting factor in their survival. They thrive on increased phosphorus. Secondly and more insidiously, recent research has indicated that glyphosate actually enhances the growth of blue-greens. The blue-greens apparently have the ability to absorb glyphosate directly from the water and some are tolerant to it or become adapted to it by rare genetic mutations.
OK, but rare genetic mutations are just that – rare! So what?
Well, you remember that blue-greens are actually bacteria, not true algae. As such their genetic material is distributed throughout the cell, and they reproduce by binary fission producing endless clones. There is no “mix-and-matching” of chromosomes and genes such as occur in nucleated organisms using sexual reproduction that tends to dissipate the effects of mutant genes. Once a cyanobacterium has undergone a mutation, that mutant gene is replicated again and again as the cell divides. It produces clones of the mutant cell, and if that mutant has an advantage (such as resistance to or affinity for glyphosate), it will rapidly spread.
A more familiar example is the recent rise to prominence of so-called superbugs that are resistant to antibiotics. Human infections are often related to bacteria that enter the body, and are treated by the intake of prescribed antibiotics as a course of treatment for a number of days. If the antibiotics are not taken for an adequate period of time, the residual bacterial population includes mutants that resist the drug in question, and in turn that drug becomes less and less effective against new infections. This way a superbug is created e.g. MRSA (methicillin-resistant Staphylococcus aureus). So think of the blue-greens as bacteria (which they are) and glyphosate as an antibiotic (which it is). Those blue-green cyanobacteria that survive the glyphosate thrive as mutants and have the capacity to spread widely.
Do blue-green blooms last forever?
No. Eventually the blue-green bloom uses up available resources and requires more nutrients than are available leading to a decline in the number of cells in the water column. Also in temperate climates, the onset of winter temperatures can put an end to algal blooming for that season.
Then what happens?
The blue-green cells die off and sink to the bottom of the lake or estuary. Other bacteria move in and use the debris from the dead blue-greens as a source of carbon, and use oxygen in the water to fuel their own growth. This in turn leads to oxygen depletion that can be very severe. Without oxygen in the water, normal aquatic life becomes impossible and a dead zone is created: fish move away, and other organisms die that can’t move into more oxygen-rich environments.
How many blue-green algae/cyanobacteria exist?
About 2500 living species have been described in the literature but probably double or treble that number exist and await discovery and description. They have a very long geological history. Fossilized blue-greens have been discovered in rocks 3.5 billion years old.
How many are harmful?
Only a dozen or so species are actually harmful when they form blue-green blooms and emit toxic substances. In the recent outbreak, Microcystis aeruginosa has been identified as a bloom-forming cyanobacterium together with a couple of others.
So which blue-greens are responsible for the Lake Okeechobee and St Lucie River blooms?
The Florida Dept of Environmental Protection (DEP) took a number of samples from sites in Martin County and adjacent areas from Late May to Late June 2016 and the results are available at their website:
https://depnewsroom.wordpress.com/south-florida-algal-bloom-monitoring-and-response/
Most samples are reported as “mixed algae; no dominant species in the sample”, but a few are reported with more detail (numbers are depth in meters):
| Martin County
St. Lucie River, Central Marine Marina (N 27° 12′ 55″, W -80° 15′ 18″) |
0.3 | Dominant taxon: Microcystis aeruginosa |
| Martin County
Dire Point Canal (N 27° 12′ 24.47″, W -80° 16′ 16.90″) |
0.3 m | mixed algae; no dominant species in sample though specks of Microcystis aeruginosa present. |
| Martin County
SE Harbor Pointe Dr. (N 27° 12′ 12.44″, W -80° 12′ 44.77″) |
0.3 m | mixed algae; no dominant species in sample though specks of Microcystis aeruginosa present. |
| Martin County
C-44 and S. Fork Mouth (N 27° 7′ 46.13″, W -80° 15′ 58.02″) |
0.3 m | mixed algae; no dominant species in sample though specks of Microcystis aeruginosa present. |
| Martin County
S-80 (N 27° 06′ 41.87″, W -80° 17′ 06.08″) |
0.5 m | Dominant taxon: Planktolyngbya limnetica |
| Martin County
Lake Okeechobee – Port Mayaca S 308 C Upstream Lake Side N 26° 59′ 6″ W -80° 37′ 16.5″ |
Water column | Dominant: Microcystis aeruginosa |
| Hendry County
Lake Okeechobee near Channel Marker 9B N 26° 46′ 36.6954″ W -80° 54′ 8.676″ |
Water column | Co-dominant taxa: Microcystis aeruginosa and Dolichospermum circinalis |
Clearly, Microcystis appears to be important in several blooms, but quantitative and qualitative data are not provided for the majority of samples, making further evaluation impossible at this time. Dolichospermum (aka Anabaena) is a well known blue-green that produces nerve toxins and liver-damaging toxins, as does Microcystis. Planktolyngbya limnetica is another well known toxic blue-green.
How adequate has the sampling and analysis program by DEP been?
It is difficult to say for sure, since DEP only provides results of their program, not the sampling and analytical strategies themselves. However, from what can be gleaned from their website it would seem that during the month of June 2016 DEP collected 24 samples from 7 counties (Martin, Palm Beach, St Lucie, Lee, Charlotte, Hendry, Glades) over a 29 day period, covering a transect from the Atlantic coast to the Gulf of Mexico (Stuart/Palm Beach to Fort Myers). Of those 24 samples, 83% were reported “mixed algae; no dominant species in the sample” without further details. I would judge this to be a token response to what is clearly a major emergency. The analytical results appear to be lackluster to judge from details available on the website. No doubt DEP activities are constrained by their budget, but the lack of urgency in attempting to characterize these blooms is disappointing at best and may eventually be judged negligent to some degree.
What is known about Microcystis aeruginosa?
Quite a lot. It is the most common harmful algal bloom-forming species in freshwater. The cells are tiny but colonies can be macroscopic in size and contain gas vesicles that allow the colonies to be buoyant and float to the surface of the lake. It produces both neurotoxins and hepatotoxins that contaminate the water and have been known to kill dogs, other large animals and livestock in general that drink the polluted water. The toxins may be carcinogenic. Microcystis has a drastic effect on dissolved oxygen in the water that can lead to mass fish kills.
Can blue-green algae live in salt water?
This depends on the species. Many truly marine blue-greens are known in seas and oceans where they play an important role in nitrogen fixation and are important components of the marine ecosystem. In the case of Stuart and the St Lucie inlet and estuary, these natural estuarine waters have been diluted and/or replaced by fresher water discharges from Lake Okeechobee as shown in recent Florida Oceanographic Society water quality reports:
http://www.floridaocean.org/uploads/docs/blocks/867/160630.pdf
In turn this has allowed freshwater blue-greens such as Microcystis to establish colonies and blooms in areas that otherwise would support more saline organisms. So, for example, on June 30th 2016, the north and south forks of the St Lucie River, the St lucie River adjacent to Sewells Point, and the Manatee Pocket were reporting salinity values in the range of zero to 13 parts per thousand, areas which otherwise would be in the range of 15 to 30 parts per thousand. Hence some of these diluted saline waters can now support freshwater blue-greens.
Alarmingly, recent laboratory-based research has shown that some blue-greens – such as Microcystis – can build up resistance to increased salinity and, therefore, if this happens in the natural habitat can expand their range from freshwater to higher salinities.
What can be done to improve the situation?
If you have a vote at any level of government, contact your elected politicians to highlight the urgent nature of the blue-green blooms and to bring pressure to bear to use available resources to solve the matter.
- Stop the back pumping of run-off water by anyone into Lake Okeechobee.
- Curtail the heavy application of phosphorus-rich agricultural chemicals in farmland surrounding Lake Okeechobee.
- In particular, request a thorough scientific investigation into the effects of glyphosate (Roundup) on blue-green algae (cyanobacteria) and their blooms.
- In the long run, demand that the dike surrounding Lake Okeechobee be rebuilt with a view to diverting southwards the impounded waters back into the Everglades.
Dr and Mrs Norris
