Dynamic accumulation and passive ionic uptake crossroads?

[Douglas.Curtis]

The question is why do cannabis plants act as dynamic accumulators (looks awesome while absorbing and permanantly fixing excess elements to tissue) for some heavy metals? Obviously they fix many other elements, but I would like to focus on the toxic heavy metals. Taking cadmium as an example, cannabis obviously has very little need for the excessive amounts it is capable of absorbing. Why does it so readily absorb it, and are there conditions/examples of plants which, given the same soil, did not absorb as much?

Is it possible there is an element the plant is looking for and, in the absence of this element, getting heavy metals instead during the chase?

 

[Douglas.Curtis]

OK, similar effect being observed but with the same element in two forms.

Tissue analysis shows high levels of iron, but in the form of oxides. The plant is apparently absorbing no usable forms of iron because the sap analysis shows low levels.

The interesting bit is what happens when the iron deficiency is fixed through foliar applications. When the iron levels in the sap rise, the iron oxide levels in the plant drop.

Proper balance within the plant fixes the absorption of unnecessary and unusable elements.

 

[Ca++]

They are not as selective as we might think. That is why we must supply things in about the right ratio.

Their efforts to get K will often get Na. Many plants (not specifically canna) can substitute Na for K, not just accumulate it uselessly. As much as 80% of the K need can be substituted. Resulting in a softer tissue.

I feel quite sure they pull up unwanted stuff by the same mechanism that was fishing for something else. Though looking at K and Na I found I was quite clueless as to why.


Could be an interesting thread Douglas. The title alone had my jaw fall

 

[Tom Hill]

Because they have roots lol?

 

[Douglas.Curtis]

Great example, and one (among many I am sure) I was not aware of. So substitution exists, wanting one element and absorbing another instead. Does this translate to fixation of excesses, making it accumulate the Na when it is present in too high a concentration?

 

[xet]

The question is why do cannabis plants act as dynamic accumulators (looks awesome while absorbing and permanantly fixing excess elements to tissue) for some heavy metals? Obviously they fix many other elements, but I would like to focus on the toxic heavy metals. Taking cadmium as an example, cannabis obviously has very little need for the excessive amounts it is capable of absorbing. Why does it so readily absorb it, and are there conditions/examples of plants which, given the same soil, did not absorb as much?

Is it possible there is an element the plant is looking for and, in the absence of this element, getting heavy metals instead during the chase?

co2 levels during the times of the dinosaurs were 5x or some even suggest hundreds of times what it is today. The plants could have easily been 50x larger (5x co2 in your tent is not a comparison of those days). Cannabis adapted through a lot and could do it again.

Also, fungus.

 

[xet]

There was also a lot more radiation in the soil and atmosphere.

So much missing knowledge

Check this out https://physics.stackexchange.com/q...rth-rotated-once-in-17-hours-rather-than-abou

 

[Three Berries]

3kppm CO2 and it's a calcium junkie.

 

[xet]

variations on a wide range of time-scales, operational time-scales of hours and days up to solar cycles and longer, day-to-day variability of peak ionosphere F2-layer electron density, NmF2, variability versus local time, season and solar cycle, average years of medium solar activity (solar decimetric flux approximately 140 units), daily fluctuations of NmF2 have a standard deviation of 20% by day and 33% by night, patterns of behaviour of ionospheric and geomagnetic variability, in particular the equinoctial peaks, midlatitude station Slough, standard deviations of day-to-day and night-to-night values of Slough NmF2 at first increase with increasing length of the dataset become fairly constant at lengths of 10–20 days and then increase further (especially at equinox) because of seasonal changes, evidence of two-day waves, geomagnetic and ionospheric data, and taking account of the day-to-day variability of solar and geomagnetic parameters, a large part of F2-layer variability is linked to that of geomagnetic activity, and attributed to the rest of ‘meteorological’ sources at lower levels in the atmosphere, enhanced auroral energy input, lack of strong photochemical control of the F2-layer of the ionosphere that exists by day.

There are so many variables, when asking why higher cadmium one could equally ask why higher radiation? What is radiation? Higher energy? Why higher energy? Higher photosynthesis? Bigger plants, more oxygen production per plant, more oxygen consumption on the planet, very fast days at 17 hours. Some things to consider

 

[Ca++]

Great example, and one (among many I am sure) I was not aware of. So substitution exists, wanting one element and absorbing another instead. Does this translate to fixation of excesses, making it accumulate the Na when it is present in too high a concentration?

Beach plants such as coco can only exist there as they can store large amounts of Na (salt). This is why breaking down coco releases so much. I believe cannabis is more typical of inland plants, and can use a certain amount but has a very low capacity for storing what it can't actually use. Hence sodium toxicity can happen.

This area interested me briefly as a coco grower under LED. It seemed for me, that the high K and Na values from decomposing coco needed rebalancing towards K dominance. Nothing wrong there, and it's documented. However, it gives so much K and Na in solution, that LEDs desire for Ca was looking hard to satisfy when pushing them hard. The K Ca Mg triangle, effected by Na, is a lot of feed. There are some leaf signs associated with high light, that are otherwise unexplained. But fit with Ks replacement by Na. Though only tissue samples will ever give the idea any weight.


Perhaps we should both have a read of how plants take up food. The real nitty gritty of the ion exchange seems to be just about hydrogen exchange. Which could really be for anything. It's just not specific about exactly what it wants. I need to read, as I think that's not the only method of taking in. With calcium absorption playing on my mind. Yes, there is a charge exchange, but fluid movement is such a factor. I know I don't know enough to really answer your question, but I'm sure the answer would become apparent from perhaps just a wiki page

 

[Douglas.Curtis]

Cadmium is simply one element known to be accumulated by cannabis. An example, if you will.

The question is more about why the passive ionic uptake path is bringing in unusable elements. Granted, the answer will likely be rather different for standard grows than for fully functional live soils. I'm interested in the answer for both methods of course.

Anyone have comprehensive links on the fixation process for excess elements, A.K.A. dynamic accumulation? I'm looking for additional info on how the plant does this. Perhaps there will be clues in the dialog.

 

[xet]

There is no such thing as unusable elements.

It's paramagnetism at work.

 

[Douglas.Curtis]

More clearly stated would be to say elements in an unuseable form without conversion. My apologies.

Again, cannabis has no need for excessive amounts of heavy metals, yet they are accumulated under many conditions.

Feeling like I'm not properly explaining my meaning, since most of the replies are not hitting anywhere in the correct universe.

 

[troutman]

Humans have no need for lead or mercury and yet will accumulate them if they eat from the dump.
It's possible that unless an organism can metabolize something it can build up inside of them.

 

[xet]

cannabis has no need for excessive amounts of heavy metals, yet they are accumulated

Clearly it has a need Mr. Universe.

 

[xet]

unuseable form without conversion

Is that how you gauge usability?

 

[Douglas.Curtis]

Comprehension is a wonderful skill to practice... I see a great lack of it on this site. Ty so much for sharing.

 

[Ca++]

I just don't think the plant has a choice. As you say, it's passive uptake. Some unwanted things tick enough similar boxes to wanted things, to be taken instead. The plant has little control over how much wanted stuff it gets also. Hence we can over feed. Plus the need to give a balanced diet. Some people do coco with no runoff. They tend to have a method, but essentially the plants is taking everything it's given. They are quite selective compared to the average plant, but perhaps nothing like what you might imagine.

I think I'm hearing the right question.

A jigsaw piece can often interlock with another in the wrong position. Rendering the pair a bad fit. Yet they can still fit somehow. How we then build around that may work to differing degree's

 

[Douglas.Curtis]

Yes, you are in the convo, ty so much.

I've been listening to a lot of stuff by John Kempf and I believe the plants do not have a choice, as you say, but that what they absorb is dependant upon many variables. There is strong evidence plants will not absorb unwanted/non-plant usable forms of an element when they have access to the correct form within the plant.

Again, going back to wondering what cannabis could be wanting (and not having access to), that ends up pulling the heavy metals instead.

What is not available in excess does not get accumulated . Prevent the quest? lol

 

[Ca++]

You want to accumulate some things though. I load P through veg. Some feed regimes also do this.
John likes to load Ca. I have followed this but I'm aware it's somewhat immobile.