I really like this a lot. I think it is definitely the future of mining in some areas, and with some metals. It wasn't that long after I started to research dynamic acculuation of minerals and nutrients in permaculture and read about the use of plants and fungi in cleaning up heavy metal and toxic sites, that I came to similar conclusions about mining for metals. Nowadays, a lot of mining is speculated via the variations in plants that are growing in an area. This is done by satellite, and via light spectrum analysis. T
The primary flaws I see in making it worthwhile for the industry to invest in it are:
1) Minerals deeper than plants can access. All mines are created in places of high concentration for a reason. The need to maximize where they can gain the most from the smallest area, for purposes of permitting of access and (in the era of environmental thinking) of limiting the area of impact. Although plants can do this up to 10 times as efficiently, plant roots, and thus the depth that they can access, are limited to a very shallow range in the crust of the Earth (especially when one considers a small herbaceous plant as was highlighted, but this should also include trees). Many strip mines, and mines in general, are going to be digging deeper than that as that's where the accumulation often trends. So, unless I am misunderstanding the process that would be necessary to make this worthwhile, this is unlikely to stop the strip mining of the area in order to gain the mineral in question at a volume worth setting up the 'mineral farm'.
2) Invasive Species: The plants that best accumulate any given substance are probably not from the area where the mining needs to take place. This then puts us into the position of importing and experimenting with potentially invasive species situations, often in sensitive wilderness areas.
3) The potential 'need' for the genetic modification of the plants: If the plants are not well adapted to that climate (or to super accumulation of the specific heavy metal, if they are adapted to the climate but only accumulated it a bit), then it potentially gives an incentive to genetically modify the plants to do the job.
4) The unlikelihood that forests would be left intact. While he does speak about simply harvesting the leaves off the trees (this leads to other questions, such as how many leaves can be healthily removed from given trees, and how will this be accomplished?-but I can see it being possible) the narrator says that the forest would be left intact, but goes on about the benefits of what single species could do, and most of the research was done on the hyperaccumulation of a given metal in isolated single species. The way I see the industrial model, is that this would require the clearing of the forest, and the planting of a monocrop. Not that this would necessarily be comparatively bad (in comparison to a strip mine, or in comparison to a strip mine + toxic heavy metal separation processes) and in a tropical place like Indonesia, where the revegetation process, post-mining, might be quite rapid if done with permacultural plantings of native pioneer trees. But still, that is a great deal less than leaving the forest intact. Given the potential to harvest mineral-rich sap from trees, It might be possible to tap them for sap like maple syrup or rubber, and then reducing the sap to a solid and then burning to ash. This might be a better way to extract the minerals?
Not to be a naysayer, because this definitely has massive potential merit, particularly if a wealthy person decided to risk some of his excesses to experiment with such a worthy project.
Interesting that he brings up Elon Musk, as the tesla batteries are responsible for extensive surface mining of lithium.
The pluses are that, even if strip mining and then planting monocrops in the substrate:
1.) this is Massively free of toxins!
2.) up to 9/10 of the area could potentially be left intact at any given time. <<- although (sorry, another downer) this is unlikely without an altruistic philanthropist attitude driving the process (step in, any time Musk, Besos, insert random rich folk here). Greed massively dominates this industry globally, which has way fewer regulations compared with other primary industries, like forestry (at least in Canada), and even supposedly heavily regulated industries (like forestry) are dominated by industrial greed rather than environmental stewardship, and they will do what they can to maximize profits while minimizing the environmental protection costs in the process, and industries have huge lobbying power to have those regulations minimized or loopholes in the regulations to allow business pretty much as usual.
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