Re:Evolution of tree roots may have driven mass extinctions
by ketanmaheshwari on Wednesday March 08, 2023 @08:38AM
(#35068814)
The article says that tree roots released massive nutrients into the oceans during the period of decay causing algae bloom depleting the Oxygen and triggering the extinction. Why just the roots and not the entire trees? Wouldn't the entire tree be decayed and end up in the ocean?
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Re:Evolution of tree roots may have driven mass extinctions
by bleuarff on Wednesday March 08, 2023 @08:47AM
(#35068904)
My understanding is that a root system is much more efficient at extracting nutrients from the ground that whatever plants used before.
Re:Evolution of tree roots may have driven mass extinctions
by hoseja on Wednesday March 08, 2023 @09:02AM
(#35069055)
The roots speed up weathering of rocks.
Re:Evolution of tree roots may have driven mass extinctions
by adammarples on Wednesday March 08, 2023 @11:08AM
(#35070727)
Yes, but trees were not really possible until roots evolved.
Re:Evolution of tree roots may have driven mass extinctions
by woopsn on Wednesday March 08, 2023 @03:00PM
(#35073979)
There was no soil yet at this time. Plants rooted directly into rock, turning the surface into gravel/sediment, weathering and runoff carried minerals and carbon away into the water. The landscape's stability depends on the roots, and so during mass extinction events, minerals and carbon get dumped en masse from the continents into the sea, and atmospheric CO2 levels drop because of weathering.
That part is relatively well established. This paper looks at the transport of phosphorus in particular, from terrestrial rock into marine ecosystems.
Plants can't take up phosphorus in its mineral bound form. Modern trees have micro-organisms living on their roots that release P (and N etc) from the soil. In certain periods of the Devonian era, P would have been primarily liberated from the rock by acids let off by the plant roots as they decayed.