Nonlimiting Nutrient Info Request

[Philosophos]

Hey everyone, I'm just looking for some good studies showing situations with nonlimiting nutrients that distinctly do not induce algae. I could pick through the google pile, but I'm sure enough of you have bookmarks handy. Reading through studies to find a noted lack of algae is a bit of a PITA.

I'd be happy to return the favor should anyone else ever be looking for information I've got that's time consuming to search for.

-Philosophos

[Tom Barr]

With aquatic plants or?

Bachmann, Crismann, Hoyer etc for Florida is where you might find the most info, not much has been done really, it's not much of an economic applied issue.

"Critical concentrations"

Gerloff 1966 etc

Will help.


Regards,
Tom Barr

[Philosophos]

I was hoping for some ex situ kinda stuff just to show the principles of non-limiting nutrients/CO2 as detailed studies. So far what I'm finding is mostly phosphate related eutrophication related stuff.

Still, the key words you gave me ran me into Mark Hoyer's page on U of F's IFAS site and a pile of his work. I'll leave the link for others who happen by this thread:

Mark V. Hoyer

-Philosophos

[Tom Barr]

Well, there's no correlation in natural systems, that are shallow, planted, with submersed plants etc from low to high nutrient ppms for N or P.

Bachmann's et al 2002 paper clearly showed this with a 300-400 lake survey where plants are present.

If no plants are present, I think water ppm's for N and P will correlate with algae pretty well.

Regards,
Tom Barr

[Biollante]

Hi Philosophos,

My generally useless $US .02.

I suspect that, as with many things in the planted aquaria world the data are just not available. As Tom Barr said no money in planted aquaria research, wetlands preservation, restoration, weed control, water/wastewater treatment and so forth, big $US, planted aquaria, low rent, niche hobby at best.

If we want data, we gonna have to produce that data and when I say we, I really mean you.

All seriousness aside, it is up to those interested to do and/or fund the research and most of it is just one plant, one species at a time day in day-out, totally unglamorous, observation.

Biollante

[Philosophos]

I was hoping some ecologist or other would be interested in eutrophication enough to have tested all of this outside of a lake. It would make sense to pull various elements apart, deconstruct them, and figure out basically how to build a lake in order to understand it better.

I'd do the whole works right now if I had the equipment and funding. As it is, I've got other experiments that meet my budget right now... as soon as I get my drop checker back from someone who's borrowing it.

Speaking of which, that experiment got somewhat off the ground before I lent out the drop checker. Early tests are looking like CO2 in the tank looked about the same after 5 days when undisturbed as they were with an air stone constantly. Before that, the levels were lower and far more inconsistent. This is an experiment I'm going to be coming back to re-do with the drop checker, and likely again in the future if Tom's pH probe CO2 meter concept becomes something I can get my hands on. Again, time and money for that one.

-Philosophos

[Biollante]

I was hoping some ecologist or other would be interested in eutrophication enough to have tested all of this outside of a lake. It would make sense to pull various elements apart, deconstruct them, and figure out basically how to build a lake in order to understand it better.

I'd do the whole works right now if I had the equipment and funding. As it is, I've got other experiments that meet my budget right now... as soon as I get my drop checker back from someone who's borrowing it.

Speaking of which, that experiment got somewhat off the ground before I lent out the drop checker. Early tests are looking like CO2 in the tank looked about the same after 5 days when undisturbed as they were with an air stone constantly. Before that, the levels were lower and far more inconsistent. This is an experiment I'm going to be coming back to re-do with the drop checker, and likely again in the future if Tom's pH probe CO2 meter concept becomes something I can get my hands on. Again, time and money for that one.

-Philosophos

Hi Philosophos,

I think one problem with studies of lakes and wetlands as far as I can tell is the systems are far more open than our little tanks and with computer modeling, I suspect it is pointless.

One small point to consider is the water movement, we turn the tank water volume over 15 or 18 times and think it a lot, you read the folks afraid that at 25 times turn over, their plants and fish will be ripped to shreds.

Then calculate a lazy half knot or knot stream or lake circulation and see how many times you would need to turn the tanks water volume. I have set up a couple of raceways and it is interesting.

Then the other difference eutrophication in the world is generally a result of non-point sources of nutrients, whereas ours is distinctly point sources of nutrients.

Your drop checker dilemma; I have found multiple drop checkers handy, even with my new gizmos. I use test tubes and a hunk of tubing, that way I can monitor any number of locations simultaneously.

If you have, a Fry’s Electronics around they have cheap 25 or 30 ml, el–cheapo test tubes. I love this set up because I can stick the tubes in groups of plant high and low. They even work for the ‘instant read’ versions using gas permeable membrane, such as the inside of mailers you can obtain from mailboxes almost anywhere.

Biollante

[Tom Barr]

The lab vs the bench scale vs the field test vs the natural systems, WHERE plants are present, and your management goal is providing good growth and that you plan to also prune and maintain the biomass( a huge labor given that they are weeds).

Sort of specific.

I sort of doubt ecologist, limnologist really are that interested in artificial aquarium systems that grow aquatic weeds.

Unles sit's for agriculture/aquaculture, some $$$ involved, not really.

For lakes, they want clear water and no labor to maintain it.
So weeds choke things, and algae gives pea soup, there's not that much in between.

Weeds or pea soup.

I think management wise, draw downs beat the weeds back each year good, and make the labor easier.

Some spray herbicides to beat them down.
Some just watch and observe as the weeds take over and choke everything.
Then cry about who if they'd only known when it was just a little problem(classic invasive species manta, hindsight is always 20/20)

I think you will find that isolation of the components is tougher than you might think. They need to be all together to work like a real system(aquarium or a lake etc).

I can induce GW in some systems, but not others using NH4.
Higher light is more sensitive to changes than say low light, some plants are more touchy than others etc. CO2 factors........water changes, filter flow.

You can vary these and build on them using the others independent of the dependent variable/s.

Few have such control unfortunately(many like to think they do, but do not verify that they in fact do, then rush to conclusion without being sure of that, thus make the mistake). I'm just not that sure.

I know what it cannot be under some conditions.
That's about it.

Folks think I know a lot, but really? Not much.

Regards,
Tom Barr

[Philosophos]

Okay, so I can scratch the idea of finding good research on non-limiting nutrients for now.

It's a shame limnologists are so interested in killing all of this stuff off. I know in some cases it's for the sake of the ecosystem, but so often it also seems to be for the sake of recreation. I guess it's all a matter of who's signing the paychecks.

It's too bad that aquatic plants have nothing like the Axelrod's to lay foundation work. It seems that any large quantities of money involved with this hobby keeps the research to its self for the purposes of marketing products.

I'll keep plugging away then.

Tom, you know tons compared to most of us. You're just very critical of what you know, which is something I can not say the same of for everyone. It's a good quality; it keeps your posts encouraging others to look to the next step rather than drawing conclusions too early. Sometimes it pisses us off when we just want an answer, but I know I'd rather have an honest "It depends" or "I don't know" than some sort of fabricated tautology.

-Philosophos

[Tom Barr]

Well, limnologist/phycologist/botantist are not focused exclusively on killing the stuff off, rather, seeing how their research can be used to manage it and understand it.
They get some basic science, relationships etc along the way and they(folks wanting to manage) do fund research

So practical applied problem solving is more what they do.

No one is just going to give you $ to play around with little applied practical use.
A few curious planted aquarist really does not constitute a particularly large market nor a source of funding

That is the way it is.
Commercial aquatic plant growers need no such research either, they are more worried about temps, sales, new species, day to day business operations, they already can grow tons of plants without issue at very large scales, they are weeds after all.

While a noble question, few have understood why it has not been answered.
Some evidence might come from the FL Everglades research groups with periphyton. Not submersed systems in most respects(aquatic tend to be all emergents 40-80% of the year).

Even making controls in aquariums is tough.

Regards,
Tom Barr