Matworld - the biogeochemical effects of early life on land.
© 2016 The Authors © New Phytologist Trust
There is growing evidence that life has been on land for billions of years. Microbial mats fuelled by oxygenic photosynthesis were probably present in terrestrial habitats from c. 3.0 billion yr ago (Ga) onwards, creating localized 'oxygen oases' under a reducing atmosphere, which left a characteristic oxidative weathering signal. After the Great Oxidation c. 2.4 Ga, the now oxidizing atmosphere masked that redox signal, but ancient soils record the mobilization of phosphorus and other elements by organic acids in weathering profiles. Evidence for Neoproterozoic 'greening of the land' and intensification of weathering c. 0.85-0.54 Ga is currently equivocal. However, the mid-Palaeozoic c. 0.45-0.4 Ga shows global atmospheric changes consistent with increased terrestrial productivity and intensified weathering by the first land plants.
This work was supported by the Leverhulme Trust (RPG-2013- 106).
This is the final version of the article. The definitive version is available at http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1469-8137
Place of publication