Nutrients and Algae, Again

[aquabillpers]

For those who still believe that excessive nutrients, particularly phosphates, can't cause algae, here is a link to an article in the Syracuse (NY) Post Standard of September 27, which discussed the rehabilitation of Lake Onondaga. Scientists marvel at Onondaga Lake's 'spectacular' progress

The gist of the article is that this formerly heavily polluted lake is now much improved, due largely to a reduction of phosphates from 120 ppm 22 years ago to 17 ppm today. The main reason for that reduction was the upgrading of a large sewage treatment plant, but there were other reasons also.

The article quotes biologists as saying that the excessive phosphates caused algae to grow profusely, and that in turn prevented higher plants from growing.

At some point in the future, the higher plants will return, they will do their water purification thing, and the lake will be clear again.

Bill

 

[Tom Barr]

Such a conclusion is very misleading.

Charles suggest the same thing here:

http://fishweb.ifas.ufl.edu/Faculty Pubs/CanfieldPubs/LimitFact.pdf

Read specifically page 27 on the lower left.
Are your tanks deep water and without plants etc or shallow with plants?

17ppm of PO4 is hardly limiting...............but the actual measurement is 17 ppb
Be careful with units and types of test methods, they make a difference.
However, the most obvious issues:

1. Other factors besides PO4 removal are at play here as well as 10X more light than we ever use.
2. Years of abuse of sewage, which contains all sorts of things, not just fertilizer.........(100)
This is not a controlled example for PO4 or just NH4.

3. Does your aquarium freeze over every year and has a dimitic mixing? Go from say 20 c to freezing every year?
Probably not

4. Does this Lake even have the ability to grow plants on all the sediment all the way across the lake? How much is actually suitable for aquatic plants to grow?

5. Sedimentation blocks light and can cover and kill plants also, not just algae.
Sewage and runoff increases sedimentation by several orders of magnitude.

"The sewage cleanup a $558 million project supported by taxpayers is part of a larger effort to restore one of the most polluted lakes in the nation."

Seems like a messy lake..........hardly a model for aquariums.

"Honeywell International is paying for the other half of the $1 billion cleanup, which involves removing or burying toxic waste in and around the lake."

Do you add toxic waste to your aquarium?

"Scientists also measured a substantial decrease in the amount of harmful ammonia entering the lake from the Metropolitan Sewage Treatment Plant on Hiawatha Boulevard in Syracuse."

Gee, perhaps that is part of it as well?
Most northern lakes have a 2 clear water phases and a number of algae dominance cycles per year. But this is not including aquatic weeds, mostly just algae.

This is basic text from Limnology books, nothing new there.

To find a good study that does factor in the more stable warmer temps, more shallow lake bottoms capable of supporting high % of surface cover with aquatic plants, habitats where algae and aquatic plants are in a more stable environment and on equal footing, Florida has the best studies and the most lake research.

"Nitrates are changing the lake's chemistry in a good way, reducing the amount of methyl mercury released into the water."

This is pretty cool. But also suggest if you want to use whack logic that NO3 is good.

"82 tons of mercury dumped into the lake over decades by the former Allied Chemical factory complex in Solvay."

Well, hope you are not adding that to your tank

Still, good news for the lake clean up and a look at how bad things can get and how they fixed it. Still, it does not support that lowering PO4 in the presence of a sizable aquatic plant biomass, that algae will dominate or not.

Is this what you are saying here?
New research suggest?
Nope.

They reduced not only PO4, but a number of serious factors like Hg and NH4...........reduced sedimentation, removal of sediments. I've never claimed that dumping sewage and high NH4 into an aquarium does not cause algae. No one has that I am aware of.

We have extreme water hyacinth problem in the Sacramento San Joaquin River delta, huge Egeria densa, Cabomba problem, pondweeds etc ,no algae issues, high nutrients. But the depths are generally shallow, same for the irrigation canals and all the rice produced here. Most soils are Nitrogen limited here, not PO4 limited in CA wetlands.

Plenty of specific applied research to the issue with aquatic plants in lakes in Florida. Read up. You add more PO4, you get more aquatic weeds, not algae dominance. Instead we get horrid weed issues, not algae.
From CA to FL, same things.

Same deal in the Evergaldes- cattail replaces native Caldium when you add more PO4, on hard marl surfaces, aquatic plants cannot grow and traditionally the PO4 levels where too low for aquatic plants to live(less than 50-20ppb). Now aquatic weeds can invade traditionally algae and native plant habitat that's key for that ecosystem.

Here's some more appropriate research on PO4 in lakes where there is a sizable % of the lake filled with aquatic plants.

http://fishweb.ifas.ufl.edu/Faculty Pubs/CanfieldPubs/macrophyte.pdf

You will not see any correlation between trophic state and aquatic weeds or algae. Such lakes are far far more similar to our aquariums than any references I've seen to date. Macrophytes are also often CO2 limited, algae rarely are.

Dan nails them on Okeechobee:

http://fishweb.ifas.ufl.edu/Faculty Pubs/CanfieldPubs/AquaticsOkee2.pdf

Once again, this lake is not PO4 limited in terms of algae.

I've been saying this for over 10 years and have support of folks that do excellent research, have discussed what I've seen in planted aquariums.

Every paper that addresses tropical shallow lakes with a high degree of macrophytes finds the same things. Florida has massive funding for lakes and the Everglade's restoration, they have plenty of research that asks these types of questions and they have the top folks working on the issues.

These are not relationships that are mired with low statistical power, or case studies, or where aquatic plants have no been considered at all when discussing algae and nutrients...............

The facts are we do keep aquatic plants at high densities, warm temps, we maintain a stable place for them to grow and add ferts.

Political baloney, lawsuits, business interest are involved in many such projects.
Still, it's nice to see a lake actually get fixed to "some degree", even if taxpayers forked out 1/2 the bill and the parent company only paid 1/2. Restoration is a difficult goal to achieve consistently.

Many many hands in the cookie jar and many views about what is "restored", what is success and so on.........

Just be careful on how to apply research, science etc.
It's not that simple many times.

Regards,.
Tom Barr

 

[aquabillpers]

As usual, thanks for your response. You always enlighten me.

My point was not to argue that excess nutrients cause algae in planted aquariums. I think that has been proven false and is no longer worth debating.

I am also satisfied that excess nutrients will not cause algae in natural bodies of water that have abundant plant life.

But - from everything that I've read, and, I think, from what you have said from time, excess nutrients, particularly phosphates, can cause algae in waters where there is insufficient plant life. That includes Lake Onondaga, Chesapeake Bay and other estuaries, and numerous lakes.

Page 27 of the paper you cited says the same thing.

I did overlook the fact that the sewage treatment plant was discharging large amounts of ammonia until it was upgraded. That certainly contributed to the growth of the algae. I also found it interesting that the natural processes in the lake were converting the ammonia to nitrates.

The taxpayers in that area are the same people who neglected to have that sewage treatment plant upgraded until they were forced to do it, so it is fitting that they assume a large part of the cost of the clean-up. I think one could argue that the sewage discharge did more harm to the ecosystem of the lake per se than did the industrial waste. The latter, of course, is hazardous to the health of people, but the fish and plants could probably coexist with it quite easily.

Again, thanks.

Bill

 

[Tom Barr]

As usual, thanks for your response. You always enlighten me.

My point was not to argue that excess nutrients cause algae in planted aquariums. I think that has been proven false and is no longer worth debating.

Yep.
I knew you knew that, the issue is really how many references take something like this, then get mixed up as hobbyist when we try and apply it.

I think article is great, they really are way ahead of things on this lake.

But - from everything that I've read, and, I think, from what you have said from time, excess nutrients, particularly phosphates, can cause algae in waters where there is insufficient plant life. That includes Lake Onondaga, Chesapeake Bay and other estuaries, and numerous lakes.

Page 27 of the paper you cited says the same thing.

I did overlook the fact that the sewage treatment plant was discharging large amounts of ammonia until it was upgraded. That certainly contributed to the growth of the algae. I also found it interesting that the natural processes in the lake were converting the ammonia to nitrates.

The taxpayers in that area are the same people who neglected to have that sewage treatment plant upgraded until they were forced to do it, so it is fitting that they assume a large part of the cost of the clean-up. I think one could argue that the sewage discharge did more harm to the ecosystem of the lake per se than did the industrial waste. The latter, of course, is hazardous to the health of people, but the fish and plants could probably coexist with it quite easily.

Again, thanks.

Bill

Yes, you are correct, if no other forms of plant life are there, more limiting nutrients generally = more growth/biomas,s but that only will matter if a nutrient is limiting. If it's not, then adding more will not increase growth rates.

Most lakes will process the NH4=> NO3 and then perhaps if lucky, the wetlands can help convert the NO3=> N2 gas.

In any restoration project, they generally want to restore ecosystem functions, like biogeochemical cycles like NH4=>=> => N2 gas, or long term precipitation of PO4 into sediments.

That's most often the goal, they really will never be able to really get anything back 100%, but it can still look darn nice afterwards. Some folks think restoration has a goal of 100% like it was.

There are tipping points also, sort of a hump where things are a lot harder and require lots of effort and work to get them up to the next step, but then once there, the lake will function with much less input and effort.

Same deal with our aquariums.

If we neglect things, our tanks can get algae, have other related issues, we have to do a fair amount of work to whip things back to shape. Then they run fine with less work. If we keep up on things and manage them well and have reasonable goals for our own habits/potential for neglect and are honest, then these episodes are "rare".

The lake was one of the worst examples in the USA of care.
The news is good.

Other aquatic systems have been restored and I've found overall, most aquatic systems tend to be restored faster, better than many terrestrial systems. Maybe I am just bias

Regards,
Tom Barr