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Nitrogen and climate change

Models project that land ecosystems may be able take up a considerable proportion of the carbon dioxide released by human activities, thereby counteracting the anthropogenic emissions. In their Perspective, Hungate et al. argue that these carbon uptake estimates are too high because the models do not take other nutrients such […]

Below‐ground process responses to elevated CO2 and temperature: a discussion of observations, measurement methods, and models

Rising atmospheric CO2 and temperatures are probably altering ecosystem carbon cycling, causing both positive and negative feedbacks to climate. Below-ground processes play a key role in the global carbon (C) cycle because they regulate storage of large quantities of C, and are potentially very sensitive to direct and indirect effects […]

Tree species and moisture effects on soil sources of N2O: Quantifying contributions from nitrification and denitrification with 18O isotopes

[1] Nitrous oxide (N2O) is an important greenhouse gas and participates in the destruction of stratospheric ozone. Soil bacteria produce N2O through denitrification and nitrification, but these processes differ radically in substrate requirements and responses to the environment. Understanding the controls over N2O efflux from soils, and how N2O emissions may […]

Impacts of hurricane Frances on Florida scrub‐oak ecosystem processes: Defoliation, net CO2 exchange and interactions with elevated CO2

Hurricane disturbances have profound impacts on ecosystem structure and function, yet their effects on ecosystem CO2 exchange have not been reported. In September 2004, our research site on a fire-regenerated scrub-oak ecosystem in central Florida was struck by Hurricane Frances with sustained winds of 113 km h−1 and wind gusts as high […]

Soil science: Scavenging for scrap metal

 Organisms acquire some elements from the environment with ease.  Diffusion alone often provides enough carbon dioxide, oxygen and water.  But getting other elements requires more effort, spurring unique evolutionary adaptations: instead of taking up nutrients from the soil, some plants in acidic bogs trap insects to obtain nitrogen and phosphorus […]

Coupling stable isotope studies with food web manipulations to predict the effects of exotic fish: lessons from Cuatro Ciénegas, Mexico

1. Exotic species threaten native species worldwide, but their impacts are difficult to predict. 2.Stable isotope analysis was combined with field competition experiments to predict how an invasive African cichlid fish, Hemichromis guttatus, might affect native fish in the desert springs of Cuatro Ciénegas, Mexico. 3.Stable isotope analysis suggested diet overlap between […]