5 ms·

I assume plant life is constrained by different things in different locations: - lack of water - too hot - too cold - not enough light (ground level of the

I assume plant life is constrained by different things in different locations: - lack of water - too hot - too cold - not enough light (ground level of the rain forest?) - lack of soil nutrients (rain forest?) - too much salt I'll add CO2 levels to my mental list, a constraint that's independent of location.

thaumasiotes 5y ago
> I assume plant life is constrained by different things in different locations: > - lack of water > - too hot > - too cold Hmm. There are lots of examples where plants do not grow in an area that (1) has a lot of water; and (2) is very cold. Are there any examples of a place that is too hot, as opposed to too dry? Even the cold examples might be driven more by a lack of liquid water than by temperature requirements.
- burnte 5y ago
  Too hot and plants can't properly regulate water loss, shrivel, and die. Too cold, even well above freezing, and they can have problems moving their liquids due to increased viscosity. In both extremes you can have temps too far from optimal that inhibit enzyme reactions, killing the plants.
- wumpus 5y ago
  The hottest day of the growing season can significantly damage wheat and corn yields, despite typical rainfall. Google [corn yield too hot].
  - thaumasiotes 5y ago
    That's a problem with corn, not with plants. Or more helpfully, it's a problem with a plant experiencing temperatures outside its natural range. There's a huge difference between "the temperature here is too hot for plants to grow" and "the temperature here is too hot for cold-weather plants to grow".
- klyrs 5y ago
  I'm not sure how you'd separate 'too hot' from 'too dry' -- problem being that places that are too hot to support plant life will rapidly undergo desertification, and then they'll be too dry.
  - thaumasiotes 5y ago
    I might look at the Nile and the oases to its west as examples. They are areas with plenty of water in the middle of what is otherwise a hot, barren desert. Plants grow there just fine. We can rule out the Sahara as a place that's too hot for plants. So do we have an example of a place that is?
- kuhewa 5y ago
  > Are there any examples of a place that is too hot, as opposed to too dry? For a given species of plant, yes. For cold-adapted plants, like those in the arctic, too warm of a winter could mean carbohydrate exhaustion due the increased metabolism, which would mean spring starvation. With climate change we see such species retreating to higher elevation or toward the poles.
bpodgursky 5y ago
It's little more subtle, but yes overall true. Higher CO2 makes it easier for plants to photosynthesize using less water, so they can grow in previously-too-dry locations.
code_duck 5y ago
Soil/water pH is very important. When pH is off, some nutrients are unavailable to plants even when present in otherwise adequate quantities. You also have to account for insects and microbes, which can either totally destroy a plant or help, in the case of soil fungi, earthworms or pollinators. Too much light can be a problem, too. Not only from heat, but simply overexposure.
tuatoru 5y ago
Yes, this is an extension of Liebig's Law of the Minimum[1]: growth is constrained by whatever nutrient is scarcest (relative to the needs of the growing organism), by extending "nutrient" to "environmental input" to include temperature, light and toxins. 1. https://earthwiseagriculture.net/grower-s-toolbox/law-of-minimums/ https://earthwiseagriculture.net/grower-s-toolbox/law-of-min...

thaumasiotes 5y ago

> I assume plant life is constrained by different things in different locations: > - lack of water > - too hot > - too cold Hmm. There are lots of examples where plants do not grow in an area that (1) has a lot of water; and (2) is very cold. Are there any examples of a place that is too hot, as opposed to too dry? Even the cold examples might be driven more by a lack of liquid water than by temperature requirements.

burnte 5y ago
Too hot and plants can't properly regulate water loss, shrivel, and die. Too cold, even well above freezing, and they can have problems moving their liquids due to increased viscosity. In both extremes you can have temps too far from optimal that inhibit enzyme reactions, killing the plants.
wumpus 5y ago
The hottest day of the growing season can significantly damage wheat and corn yields, despite typical rainfall. Google [corn yield too hot].
- thaumasiotes 5y ago
  That's a problem with corn, not with plants. Or more helpfully, it's a problem with a plant experiencing temperatures outside its natural range. There's a huge difference between "the temperature here is too hot for plants to grow" and "the temperature here is too hot for cold-weather plants to grow".
klyrs 5y ago
I'm not sure how you'd separate 'too hot' from 'too dry' -- problem being that places that are too hot to support plant life will rapidly undergo desertification, and then they'll be too dry.
- thaumasiotes 5y ago
  I might look at the Nile and the oases to its west as examples. They are areas with plenty of water in the middle of what is otherwise a hot, barren desert. Plants grow there just fine. We can rule out the Sahara as a place that's too hot for plants. So do we have an example of a place that is?
kuhewa 5y ago
> Are there any examples of a place that is too hot, as opposed to too dry? For a given species of plant, yes. For cold-adapted plants, like those in the arctic, too warm of a winter could mean carbohydrate exhaustion due the increased metabolism, which would mean spring starvation. With climate change we see such species retreating to higher elevation or toward the poles.

bpodgursky 5y ago

It's little more subtle, but yes overall true. Higher CO2 makes it easier for plants to photosynthesize using less water, so they can grow in previously-too-dry locations.

code_duck 5y ago

Soil/water pH is very important. When pH is off, some nutrients are unavailable to plants even when present in otherwise adequate quantities. You also have to account for insects and microbes, which can either totally destroy a plant or help, in the case of soil fungi, earthworms or pollinators. Too much light can be a problem, too. Not only from heat, but simply overexposure.

tuatoru 5y ago

Yes, this is an extension of Liebig's Law of the Minimum[1]: growth is constrained by whatever nutrient is scarcest (relative to the needs of the growing organism), by extending "nutrient" to "environmental input" to include temperature, light and toxins. 1. https://earthwiseagriculture.net/grower-s-toolbox/law-of-minimums/ https://earthwiseagriculture.net/grower-s-toolbox/law-of-min...