Now showing items 1-10 of 321
Adjustment of forest ecosystem root respiration as temperature warms
Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published ...
Effects of ozone on net primary production and carbon sequestration in the conterminous United States using a biogeochemistry model
The effects of air pollution on vegetation may provide an important control on the carbon cycle that has not yet been widely considered. Prolonged exposure to high levels of ozone, in particular, has been observed to ...
Correction to “Importance of carbon-nitrogen interactions and ozone on ecosystem hydrology during the 21st century”
(American Geophysical Union, 2009-08-22)
Microbial community composition in sediments resists perturbation by nutrient enrichment
Functional redundancy in bacterial communities is expected to allow microbial assemblages to survive perturbation by allowing continuity in function despite compositional changes in communities. Recent evidence suggests, ...
Eutrophication in Portuguese estuaries evidenced by δ15N of macrophytes
Terrestrial inputs of nitrogen in estuaries are increasing and altering salt marsh primary production, plant communities and associated biota. We used N isotope ratios and %N in Spartina maritima, Halimione portulacoides, ...
Species compositional differences on different-aged glacial landscapes drive contrasting responses of tundra to nutrient addition
In the northern foothills of the Brooks Range, Alaska, moist non-acidic tundra dominates more recently deglaciated upland landscapes, whereas moist acidic tundra dominates older upland landscapes. In previous studies, ...
Historical and idealized climate model experiments : an intercomparison of Earth system models of intermediate complexity
(Copernicus Publications on behalf of the European Geosciences Union, 2013-05-16)
Both historical and idealized climate model experiments are performed with a variety of Earth system models of intermediate complexity (EMICs) as part of a community contribution to the Intergovernmental Panel on Climate ...
Roads as nitrogen deposition hot spots
Mobile sources are the single largest source of nitrogen emissions to the atmosphere in the US. It is likely that a portion of mobile-source emissions are deposited adjacent to roads and thus not measured by traditional ...
Scavenging, cycling and removal fluxes of 210Po and 210Pb at the Bermuda time-series study site
Quantifying relative affinities of Po and Pb in different populations of marine particulate matter is of great importance in utilizing 210Po as a tracer for carbon cycling. We collected and analyzed water samples for the ...
Using indirect methods to constrain symbiotic nitrogen fixation rates : a case study from an Amazonian rain forest
Human activities have profoundly altered the global nitrogen (N) cycle. Increases in anthropogenic N have had multiple effects on the atmosphere, on terrestrial, freshwater and marine ecosystems, and even on human health. ...