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Soils are a crucial link between the atmosphere, biosphere, and geosphere and disturbances to the health of soils will severely impact plants as well as a multitude of organisms living in or on soils. Catastrophic soil loss is thought to have played a pivotal role during mass-extinction events as a result of major deforestation, but the exact feedbacks remain elusive. Here, we assess the role of soil loss into the end-Triassic mass-extinction event based on proxy data obtained from core material from France, Germany, England, Denmark, and Sweden. Clay mineral and palynological data indicate a strong increase in chemical weathering and mechanical erosion during the latest Rhaetian with the influx of kaolinite and abundantly reworked Palaeozoic organic matter. Based on a new timeline, these changes were coeval with intense volcanic activity in the Central Atlantic Magmatic Province (CAMP), which released large quantities of volatiles that contributed directly and indirectly to enhanced weathering. Erosion rates likely also rose in response to deforestation, repeated forest fires, and seismic activity related to CAMP emplacement. Using a novel proxy based on biological degradation of fern spore walls, the intensity of biodegradation by fungi and bacteria, a process coupled to organic matter decay in soils, strongly decreased across the T/J boundary. We interpret this as evidence for the widespread removal of soils. Taken together, CAMP induced environmental changes led to profound changes in weathering and erosion and removal of soils, while soil resilience during the Hettangian proceeded hand in hand with recovery in Jurassic seas

Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.