Divergent controls on carbon concentration and persistence between forests and grasslands of the conterminous US

Chicken or the egg. Grassland soil carbon behaves different than forest soil carbon. But is that because of the plant composition? (No). Or is it because of the climatic differences? (Probably) But if the climatic differences *also* lead to vegetation differences, then how can you separate out the climate from the vegetation? Here we attempt to do so.

Carbon–Mercury Interactions in Spodosols Assessed through Density Fractionation, Radiocarbon Analysis, and Soil Survey Information

Spodosols are the **most** photogenic soils *(personal opinion)*. Their dark organic surface horizons, followed by a light colored mineral horizon, then bookend-ed with another very dark - often red - mineral horizon makes these tri-colored soils magnificent to stare at. These Spodosols are relatively rare, but concentrated in a few places in the US where historical anthropogenic emissions are the most likely sources of Mercury. In this paper we focus on different Spodosols around the US, combining pedologic and geochemical analysis to identify how carbon and mercury interact down the soil profile.