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The article informs that Brantley et al. have studied the temperature dependence of silicate weathering, and its impact on Earth's climate. It mentions that the results showed that silicate weathering increased with temperature, with field rates increasing more than those from laboratory experiments, and highlights the complex interplay between temperature, minerals, and water in determining the rate of silicate weathering and its impact on the carbon cycle and Earth's climate.

Lithospheric organic carbon ( “ petrogenic ” ; OC petro ) is oxidized during exhumation and subsequent erosion of mountain ranges. This process is a considerable source of carbon dioxide (CO2) to the atmosphere over geologic time scales, but the mechanisms that govern oxidation rates in mountain landscapes are poorly constrained. We demonstrate that, on average, 67 ± 11% of the OC petro initially present in bedrock exhumed from the tropical, rapidly eroding Central Range of Taiwan is oxidized in soils, leading to CO2 emissions of 6.1 to 18.6 metric tons of carbon per square kilometer per year. The molecular and isotopic evolution of bulk OC and lipid biomarkers during soil formation reveals that OC petro remineralization is microbially mediated. Rapid oxidation in mountain soils drives CO2 emission fluxes that increase with erosion rate, thereby counteracting CO2 drawdown by silicate weathering and biospheric OC burial. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding impact of mountain glaciation on rapid oxidation of rock-bound organic carbon. It mentions the exposure of organic matter in rocks to oxidative weathering at the planet Earth's surface releases carbon dioxide. It also mentions th use of rhenium to track the oxidation of rock-bound organic carbon in the mountain watersheds.

The article discusses on long-term patterns of hillslope erosion by earthquake-induced landslides shape mountain landscapes. Topics discusses include information on erosion provenance using a novel combination of the isotopic and molecular composition of organic matter in Lake Paringa, New Zealand; shift in erosion provenance after four large earthquakes over 1000 years; and role of repeated large earthquakes in erosion at high elevations.

Widespread triggering of landslides by large storms or earthquakes is a dominant mechanism of erosion in mountain landscapes. If landslides occur repeatedly in particular locations within a mountain range, then they will dominate the landscape evolution of that section and could leave a fingerprint in the topography. Here, we track erosion provenance using a novel combination of the isotopic and molecular composition of organic matter deposited in Lake Paringa, New Zealand. We find that the erosion provenance has shifted markedly after four large earthquakes over 1000 years. Postseismic periods eroded organic matter from a median elevation of 722 +329 / -293 m and supplied 43% of the sediment in the core, while interseismic periods sourced from lower elevations (459 +256 / -226 m). These results are the first demonstration that repeated large earthquakes can consistently focus erosion at high elevations, while interseismic periods appear less effective at modifying the highest parts of the topography., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).)

Infrequent extreme events such as large earthquakes pose hazards and have lasting impacts on landscapes and biogeochemical cycles. Sediments provide valuable records of past events, but unambiguously identifying event deposits is challenging because of nonlinear sediment transport processes and poor age control. Here, we have been able to directly track the propagation of a tectonic signal into stratigraphy using reservoir sediments from before and after the 2008 Wenchuan earthquake. Cycles in magnetic susceptibility allow us to define a precise annual chronology and identify the timing and nature of the earthquake's sedimentary record. The grain size and Rb/Sr ratio of the sediments responded immediately to the earthquake. However, the changes were muted until 2 years after the event, when intense monsoonal runoff drove accumulation of coarser grains and lower Rb/Sr sediments. The delayed response provides insight into how climatic and tectonic agents interact to control sediment transfer and depositional processes.