Now showing items 21-30 of 309
Susceptibility of salt marshes to nutrient enrichment and predator removal
The sustainability of coastal ecosystems in the face of widespread environmental change is an issue of pressing concern throughout the world (Emeis et al. 2001). Coastal ecosystems form a dynamic interface between terrestrial ...
The Arctic freshwater system : changes and impacts
(American Geophysical Union, 2007-11-20)
Dramatic changes have been observed in the Arctic over the last century. Many of these involve the storage and cycling of fresh water. On land, precipitation and river discharge, lake abundance and size, glacier area and ...
Flow-weighted values of runoff tracers (δ18O, DOC, Ba, alkalinity) from the six largest Arctic rivers
(American Geophysical Union, 2008-09-20)
We present new flow-weighted data for δ 18OH2O, dissolved organic carbon (DOC), dissolved barium and total alkalinity from the six largest Arctic rivers: the Ob', Yenisey, Lena, Kolyma, Yukon and Mackenzie. These data, ...
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, ...
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 ...
Microbes in nature are limited by carbon and energy : the starving-survival lifestyle in soil and consequences for estimating microbial rates
(Frontiers Media, 2013-11-12)
Understanding microbial transformations in soils is important for predicting future carbon sequestration and nutrient cycling. This review questions some methods of assessing one key microbial process, the uptake of labile ...
Modeling coupled biogeochemical cycles
(Ecological Society of America, 2011-02)
Organisms require about 30 essential elements to sustain life. The cycles of these elements are coupled to one another through the specific physiological requirements of the organisms. Here, I contrast several approaches ...
N budgets and aquatic uptake in the Ipswich River basin, northeastern Massachusetts
(American Geophysical Union, 2004-11-05)
We calculated N budgets and conducted nutrient uptake experiments to evaluate the fate of N in the aquatic environment of the Ipswich River basin, northeastern Massachusetts. A mass balance indicates that the basin retains ...
Correction to “Importance of carbon-nitrogen interactions and ozone on ecosystem hydrology during the 21st century”
(American Geophysical Union, 2009-08-22)