How the colonization of terrestrial environments by early land plants over 400 Ma influenced rock weathering, the biogeochemical cycling of carbon and phosphorus, and climate in the Palaeozoic is uncertain. Here we show experimentally that mineral weathering by liverworts—an extant lineage of early land plants—partnering arbuscular mycorrhizal (AM) fungi, like those in 410 Ma-old early land pla...

The strontium isotope composition of seawater is strongly influenced on geological time scales by changes in the rates of continental weathering relative to ocean crust alteration. However, the potential of the seawater 87Sr/86Sr curve to trace globally integrated chemical weathering rates has not been fully realised because ocean 87Sr/86Sr is also influenced by the isotopic evolution of Sr sou...

Supervisory Soil Scientist, Rocky Mountain Forest and Range Experiment Station, Tempe, Arizona; and Soil Microbiologist, Pacific Southwest Forest and Range Experiment Station, Glendora, California. The weathering of parent rock may be an important source of some nutrients. The rates of weathering of the different parent rock materials vary and affect the inherent fertility and productivity of a...

Chemical weathering of silicate rocks on continents acts as a major sink for atmospheric carbon dioxide and has played an important role in the evolution of the Earth's climate. However, the magnitude and the nature of the links between weathering and climate are still under debate. In particular, the timescale over which chemical weathering may respond to climate change is yet to be constraine...

[1] Numerical models of bedrock valley development generally do not include weathering explicitly. Nevertheless, weathering is an essential process that acts in concert with the transport of loose debris by seepage and runoff to form many bedrock valleys. Here we propose a numerical model for bedrock valley development that explicitly distinguishes weathering and the transport of loose debris a...

In acidic forest soils, availability of inorganic nutrients is a tree-growth-limiting factor. A hypothesis to explain sustainable forest development proposes that tree roots select soil microbes involved in central biogeochemical processes, such as mineral weathering, that may contribute to nutrient mobilization and tree nutrition. Here we showed, by combining soil analyses with cultivation-dep...

Despite evidence that weathering plays a role in forming intertidal, estuarine, and fluvial rock platforms, many publications uncritically refer to “wave-cut” or “stream-cut” rock platforms. The alternative explanations of chemical weathering and physical water erosion of rock platforms have been debated since 1839. Our new approach to this long-standing problem introduces data from fluvial as ...

Papers published in Hydrology and Earth System Sciences Discussions are under open-access review for the journal Hydrology and Earth System Sciences Abstract Major environmental stressors of boreal and sub-arctic rivers are hydrological changes and global warming and both factors will significantly influence the future evolution of the river chemistry in high latitudes. We tested the hypothesis...

Polar optical-phonon modes are derived analytically for spheroidal quantum dots with wurtzite crystal structure. The developed theory is applied to freestanding spheroidal ZnO quantum dots and to spheroidal ZnO quantum dots embedded into a MgZnO crystal. The wurtzite (anisotropic) quantum dots are shown to have strongly different polar optical-phonon modes in comparison with zincblende (isotrop...

Metallic nanoparticles can exhibit very large optical extinction in the visible spectrum due to localized surface plasmon resonance. Spherical plasmonic nanoparticles have been the subject of numerous studies in recent years due to the fact that the scattering response of spheres can be analytically evaluated using Mie theory. However a major disadvantage of metallic spherical nanoparticles is ...