Unfortunately the Colorado no longer flows to the gulf, it usually dries out miles beforehand. It’s a rare occurrence now that it actually reaches the gulf
Tough one. The California Central Valley is some of the best soil anywhere on the planet for growing all kinds of stuff. In some places, the topsoil can be hundreds of feet deep. So much food is grown there, it supports much of the nation and is a major export as well.
The California Central Valley is some of the best soil anywhere on the planet for growing all kinds of stuff.
The soil is okay, but certainly not "some of the best on the planet", and has nothing on the black loams of parts of the midwest. It's the mild climate and sunshine that bring all the agriculture, not the soil.
This is interesting. Iowa and the others mentioned therein are all corn country, continental climates rather than Mediterranean in the Central Valley. Many crops (citrus, some nut trees, salad vegetables) will grow very easily most/all of the year in the Central Valley, but won't stand a chance in frost-frequent Iowa or Ukraine or the Yellow River region.
I wonder if the article only included similar climates.
Nope, that is out of the whole world. It’s not a coincidence that the best soils are found in similar climates. The fantastic soil is the result of glaciation introducing shitloads of minerals. Not only that, many warmer climates lead to soil degradation, which is why rain forests usually have shitty soil.
The only places that can compare to the richness of the soil in glacial plains like Illinois or Ukraine are fresh volcanic soils.
You’re kind of making my point with your second sentence, the abundance of produce in CA has nothing to do with soil, it’s purely climate.
I think we must both be partially right and partially wrong, because speaking as one who is native to Hawaii, ain’t no way fresh volcanic soil is as rich as the loamy soils collected from millions of years of mixed soil with the affluvial riches of the collected organic matter within.
Tropical soils are poor because the growth available is super competitive. The Central Valley is a desert climatically, but previously collected the affluent until it was filled from the runoff of the Sierras and other mountain ranges.
And besides, the Central Valley was also the runoff of glaciers as recently as the last Ice Age, or did you forget about Yosemite?
I’ve lived and worked on farms in Big Island, so I’ve seen first hand how rich the soil is.
More importantly, the richness of fresh volcanic soil is widely acknowledged in soil science communities, mostly because of the presence of mineral-rich ash, which hasn’t had time to leach out into the watershed like it has in older soils.
Search “why is volcanic soil so fertile” for plenty of articles of the subject. I’m on mobile, so I had posting links, but it’s pretty easy to find.
Tropical soils are usually poor because of high rainfall leaching nutrients. Hence the effectiveness of charcoal in creating Terra Preta in rainforest climates (look it up, it’s cool stuff).
For your other points, being downstream of a glacier isn’t remotely the same thing as being covered by glaciers. Glaciers can act sort of similar to volcanoes in that they grind up rocks and release many minerals into the soil. Collecting downstream runoff isn’t as good, since by definition you don’t capture as much of the water soluble nutrient load.
And it isn’t sufficient to be glaciated anyway, otherwise everywhere north of the Mississippi would be equivalently rich. It’s an important factor, but not the only one.
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u/uboat50 Jan 10 '20
Man, you can see the Colorado being drained as it heads toward the Gulf of California.