Comment Re:That's not why (Score 4, Informative) 45
I mean, from a horticultural perspective, there is some potential to gain more of other nutrients, in that if you have more energy, you can develop a larger root system, or generally more effectively, better feed mycorrhizal associations (fungal hyphae are much finer than root hairs, so can get into smaller cracks, and fungi can "acid mine" nutrients out of mineral grains - as an example, here's a microscopic image showing what they did to a garnet)
That said, yeah, in general if you can provide more energy, you expect the storage of "calories" to grow much faster than the acquisition of other minerals. Also, it's important to note that while more CO2 is generally good for most plants, more heat, or greater periods of drought (land dries out faster, monsoon belts spread) and flooding (atmosphere holds more moisture, monsoon belts spread) are not. In regards to heat as well, there's a lot of details. First off, though we commonly don't think about it, heat management in plants is critical. Their proteins are designed for function within an optimal temperature range, and to maintain it, they have to cool themselves down with transpiration, creating more water stress. Also it's worth noting that C3 plants (most plants) fundamentally don't tolerate heat as well as C4 or CAM plants (there's work to engineer C4 into some common agricultural crops... it's frankly amazing to me that they're getting some success, as it's not a trivial change).
BTW, the reason that plants grow better with more CO2 isn't what most people might think. The TL/DR is that the protein that sequesters CO2 so that (using ATP and NADPH from photosynthesis) - RuBisCo (the most abundant protein on Earth, something that has been evolving for billions of years) frankly sucks at its job. Something like 20-25% of the time (at normal CO2 levels), instead of binding with CO2, it binds with O2 instead ("photorespiration"), which means not only does it not sequester a carbon, but the plant has to *give up a carbon* to regenerate the RuBisCo. This is disastrous in terms of energy efficiency. And as a side effect, you also have to keep the stomata open more, which means more water loss. But as you increase the CO2 levels, the ratio between binding CO2 and binding O2 improves, and photorespiration waste drops. C4 plants "fix" this problem by instead of having RuBisCo directly bind CO2, they first bind CO2 into malate (with high selectivity), then the malate transports into bundle sheath cells, the CO2 is re-released, and THEN - in a high-CO2 environment - RuBisCo takes it up. This reduces photorespiration, but also introduces some more wasteful chemical conversions. (CAM plants to even further by storing malate inside vacuules - at the cost of even more energy - so that they can store it up during the night, and then use it during the day, which - although even more wasteful - lets them keep their stomata closed during the day to conserve water)
(BTW, there are some microbes that have developed a more efficient RuBisCo, but it's proving challenging to engineer it into higher plants)