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"A proto-recovery of herbaceous plants (not woody plants) occurred dozens of kyr after the end-Permian marine extinction and coincided with a global warming maximum and oceanic anoxia/euxinia (no oxygen O2) and a raised level of free hydrogen sulfide (H2S)". (Biswas et al 2020)
What had been a lush landscape was now a cauldron of magma, which re-occurred 5 million years later, making many parts uninhabitable. Because plants became stressed they did not mop up excess carbon dioxide, which was washed out by rain to the soil and sea. Without plants to hold the soil, much was washed away, leaving bare rock. The sea became a soup of debris and carcasses, which anearobic bacteria got to work on.
The decline of woody plants after the extinction was most notable, but started to regain after a few million years.
Corystosperms
Corystosperms
A group of seed ferns called corystosperms replaced Glossopteris, dominant in the south in the previous period. Corystosperms grew as forests along river banks and within proximal floodplain environments. Many , like Artabe et al 2007, have long been considered these extinct plants critical for understanding seed plant phylogeny, in particular the evolution of seed plant reproductive structures and the relationships of angiosperms. These now have to take into account of fossil find in the Northern Hemisphere (Shi et al 2016)
Pteridosperms (now extinct seed ferns) were first seed plants to evolve in a group of vascular plants.
South
South
The forests of Gondwana were dominated by extinct genus of fork-leaved seed ferns (Dicroidium - archetypal genus of corystosperms) and other fern-like plants (Thinnfeldia - aligned with corystosperms ).
Reconstruction of the Triassic Darwin Forest landscape
"in a high sinuosity fluvial system, in which channel-filling sand bodies are associated with mud-dominated floodplain deposits. The canopy is integrated by two arboreal strata and emergent trees with conifers and corystosperms"
The soils for 'channel-filling sand bodies' and 'mud-dominated floodplain deposits' had evolved in the previous period, among 'early soils'.
Less wood
Less wood
By the end of the Triassic, both hemispheres gave way to conifer and cycad vegetation. The recovery of gymnosperm forests took 4–5 million years, with an additions of other gymnosperm groups (cycads, gnetophytes) that were not originally present. A subsequent rapid increase of spore/pollen ratios marks a renewed decline among woody elements. “The time-delayed extinction signals the onset of low-diversity, open shrubland vegetation, in which cosmopolitan lycopsid taxa continue to play a central role until full recovery of closed woodland ecosystems may occur at the transition between Early and Middle Triassic" (Looy et al., 2001)
These fluctuations of the dominant flora between woody and herbaceous taxa indicate chronic environmental stress resulting in a loss of most large woodland plant species. This period had very distinct patterns of seasonality. None of the plants relied on insects for pollination.
Much soil must have been lost because of the destruction of plants which hold soil together. Millions of tons of silt would have been washed to the seas. Most researchers concentrate on land or marine death, rather than soil death. Yet there must have been places - including rocks - where recovery started. For that they may have needed lichens.
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