There has and continues to be concern about the effects of elevated nitrogen (N) deposition on natural ecosystems. In this paper, research on natural ecosystems, including wetlands, heathlands, grasslands, steppe, naturally regenerated forests and deserts, is evaluated to determine what is known about nitrogen cycling in these ecosystems, the effects of elevated nitrogen on them and to identify...

Fires are critical pathways of carbon loss from boreal forest soils, whereas microbial communities form equally critical controls over carbon accumulation between fires. We used a chronosequence in Alaska to test Read’s hypothesis that arbuscular mycorrhizal fungi should dominate ecosystems with low accumulation of surface litter, and ectomycorrhizal fungi should proliferate where organic horiz...

In this study, Nitrogen doped TiO2 photocatalysts were prepared by the sol gel method and physicochemical properties were characterized by X-ray diffraction (XRD), and scanning electron microscopy (SEM), photoluminescence, and energy dispersive X-ray spectroscopy (DRS) techniques. The XRD data indicated that the nanoparticles had the same crystals structures as the pure TiO2</su...

polyhydroxyalkanoates (phas) are bioplastics derived from renewable resources such as vegetable oils, corn starch, or microbes. the polyhydroxybutyrate (phb) is a short-chain-length pha, and the most important bioplastic produced by certain microorganisms in the presence of excess carbon sources. in this study batch cultivation of alcaligenes eutrophus with the aim of increasing phb production ...

Continental shelves are believed to play a major role in carbon cycling due to their high productivity. To improve our understanding of carbon dynamics on continental margins, a dissolved organic matter (DOM) model was developed and imbedded within an existing coupled ocean circulation-biogeochemical model of the U.S. East coast. A model simulation with the DOM module was compared with the refe...

Soil carbon and nitrogen contents play an important role in sustaining soil physical and chemical quality and help to have healthy environments. The continues conversion of rangelands to arable lands has the potential to change carbon and nitrogen sequestration. In this study to evaluate the effects of land use change on soil organic carbon and nitrogen stock, forty samples collected from north...

Several ecosystems in the western US are already undergoing nitrogen (N) saturation, a condition where previously N limited ecosystems are no longer N limited. This state of N saturation leads to adverse impacts on terrestrial ecology and water quality. Due to the complexities of terrestrial carbon-nitrogen cycling, integrated hydrologic-biogeochemical modeling provides a tool to improve our un...