Hi Clive, then how did plants evolve to rise above a blanket of algae? Areas that plants have invested a lot of time getting good at is storing energy, alternative photosynthetic highways, and potentially (or as a byproduct) generating allelopathic chemicals. They are less boom and bust merchants than algae, financial planners could do well comparing the two!
Hi mate,
Plants do not inhabit the same niche in nature that algae do. That's the one thing that people forget. The success and longevity of algae and other spore creating species is in many ways facilitated by the spore. Spores live forever, practically speaking. The best reason for any algae to bloom is in order to produce more spores which also live forever. So it isn't that the world was covered with algae 24/7 and plants somehow managed to poke their head above it. Being in the green state and having to feed cells is an expensive affair, so the algae bloom when conditions are more favorable for them. If it's cooler or darker, for example, then it's best to remain as a spore.
Plants have a different nice, so there is plenty of time to grow and develop when algae are spores. As long as they stay healthy then the blooms do not occur. Plants prefer a stable set of conditions because it takes them a long time to re-configure their chemistry for any new conditions. Algae respond instantaneously to change, especially if the change can be to their benefit. So it's a chess game. "When are conditions favorable for plants and when are they not?"
ceg4048 said: ↑ Algae is not afraid of Oxygen, high or low Is this proven? and true of all the algal species? Perhaps it is less true of hair algae and bga and more true of bba, perhaps lower oxygen levels are one of an algal spores triggers that a system is not healthy and susceptible to attack? etc...
Well, you know that there are tens of thousands of algal species as well as thousands of different systems. I can't say very much about all species, just the few that are in our tanks. Obviously, we do not see tens of thousands of different species. We see a few varieties in a couple of categories, and that's because the conditions in our tanks can be favorable to only that few.
Since BGA typically lives in a place that is more susceptible to a decline in Oxygen it can be that O2 used as a stronger trigger for that species but perhaps less so for the others that you mention. I don't know that for sure.
This sounds plausible and mirrors the stages of algal growth on a nutrient deficient leaf, but is the mechanism and type of "trigger" chemicals scientifically identified and proven or it more a reasonable hunch of what is going on based on experience, I like to read about this kind of thing, so if you have the references then please attach them.
No, there is a lot we still don't know. We have some measurements of the leakage, and that happens simply due to the breakdown of the cell walls and the release of the cell contents. There may be other materials that the spores sense as well. plantbrain will have more information on that.
So, why can't the algae just grow by itself. If these nutrients are available- why the need to care about what's going on with the plants,? Surely the evironment is suitable for both. At the same time?
It's exactly as Tom mentions above. Lots of different conditions, lots of different prey, lots of different mechanisms to survive and reproduce. If plants are around, then life can become easier. A place to anchor without being washed away, for example, while being fed at the same time.
The idea that we are trying to deliver is that we need to stop thinking about the cause of blooms solely in terms of whether we added NO3 or not, because blooms are triggered by a vast array and very complicated set of conditions, many of which we do not yet have control over, and many of which are totally unrelated to what the nutrient levels are.
Cheers,