Rising atmospheric carbon dioxide (CO2) could alter the carbon (C) and nitrogen (N) content of ecosystems, yet the magnitude of these effects are not well known. We examined C and N budgets of a subtropical woodland after 11 yr of exposure to elevated CO2. We used open-top chambers to manipulate CO2 […]
While short-term plant responses to global change are driven by physiological mechanisms, which are represented relatively well by models, long-term ecosystem responses to global change may be determined by shifts in plant community structure resulting from other ecological phenomena such as interspecific interactions, which are represented poorly by models. In […]
Scientists who study climate and ecosystems in the Arctic have weighed in on future changes in the region affecting soils, streams and wildfire, which will be releasing greater amounts of carbon dioxide and other greenhouse gases into the atmosphere.Because the Arctic is home to billions of tons of naturally occurring carbon […]
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 tundra, mosses play an important functional role regulating belowground and ecosystem processes, but there is still considerable uncertainty about how tundra moss communities will respond to climate change. We examined the effects of 5 years of in situ air and soil warming on net primary productivity (NPP), carbon (C) […]
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 […]
Bacterial vaginosis (BV) is a common vaginal bacterial imbalance associated with risk for HIV and poor gynecologic and obstetric outcomes. Male circumcision reduces BV-associated bacteria on the penis and decreases BV in female partners, but the link between penile microbiota and female partner BV is not well understood. We tested […]
Soil carbon in permafrost ecosystems has the potential to become a major positive feedback to climate change if permafrost thaw increases heterotrophic decomposition. However, warming can also stimulate autotrophic production leading to increased ecosystem carbon storage—a negative climate change feedback. Few studies partitioning ecosystem respiration examine decadal warming effects or […]
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. […]