Molybdenum (Mo) is critical for the function of enzymes related to nitrogen cycling. Concentrations of Mo are very low in sandy, acidic soils, and biologically available Mo is only a small fraction of the total pool. While several methods have been proposed to measure plant-available Mo, there has not been […]
Soil organic carbon (SOC) mass and its constituents, chemistry, and isotopic signatures (Δ14C, δ13C) were examined for two different loblolly pine (Pinus taeda L.) research installations located in north-central Florida. Both studies were designed as split-plots with the whole plots as different levels of fertilization and herbicide application (cultural intensity), […]
In the boreal forest of Alaska, increased fire severity associated with climate change is expanding deciduous forest cover in areas previously dominated by black spruce (Picea mariana). Needle-leaf conifer and broad-leaf deciduous species are commonly associated with differences in tree growth, carbon (C) and nutrient cycling, and C accumulation in […]
Increasing temperatures have been shown to impact soil biogeochemical processes, although the corresponding changes to the underlying microbial functional communities are not well understood. Alterations in the nitrogen (N) cycling functional component are particularly important as N availability can affect microbial decomposition rates of soil organic matter and influence plant […]
The causes of the Pleistocene extinctions of large numbers of megafaunal species in the Northern Hemisphere remain unclear. A range of evidence points to human hunting, climate change, or a combination of both. Using ancient DNA and detailed paleoclimate data, Cooper et al . report a close relationship between Pleistocene megafau-nal extinction events and rapid warming events at the start of interstadial periods. […]
Invasive species alter ecosystems, threaten native and endangered species, and have negative economic impacts. Knowing where invading individuals are from and when they arrive to a new site can guide management. Here, we evaluated how well the stable hydrogen isotope composition (δ2H) records the recent origin and time since arrival […]
We’ve got your number: Tracing the source of invasive Japanese beetles March 9, 2016 Sonya Daw news.nau.edu Like a Southern drawl popping up on the West Coast, our accents mark us as newcomers. With time they fade, leaving only traces of our past in the occasional slip of a word. […]
As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases […]
Perennially frozen soil in high latitude ecosystems (permafrost) currently stores 1330-1580 Pg of carbon (C). As these ecosystems warm, the thaw and decomposition of permafrost is expected to release large amounts of C to the atmosphere. Fortunately, losses from the permafrost C pool will be partially offset by increased plant […]
Restoration of native fish to freshwater habitats often requires nonnative fish removal via chemicals such as antimycin A. Despite widespread use, there are limited field studies quantifying the effects of antimycin A on aquatic macroinvertebrates. We studied the immediate and short-term effects of antimycin A on macroinvertebrates during a fish […]