Forest ecosystems may provide strong sources of nitrous oxide (N2O), which is important for atmospheric chemical and radiative properties. Nonetheless, our understanding of controls on forest N2O emissions is insufficient to narrow current flux estimates, which still are associated with great uncertainties. In this study, we have investigated the quantitative and qualitative relationships betwe...

In an attempt to reduce the threat of global warming, it has been proposed that the rise of atmospheric carbon dioxide concentrations be reduced by the ocean disposal of CO2 from the flue gases of fossil fuel-fired power plants. The release of large amounts of CO2 into mid or deep ocean waters will result in large plumes of acidified seawater with pH values ranging from 6 to 8. In an effort to ...

A membrane aerated biofilm reactor (MABR), in which O(2) was supplied from the bottom of the biofilm and NH(4)(+) and organic carbon were supplied from the biofilm surface, was operated at different organic carbon loading rates and intra-membrane air pressures to investigate the occurrence of simultaneous chemical oxygen demand (COD) removal, nitrification and denitrification. The spatial distr...

This study examined the performances of Acorus calamus, Pontederia cordata, and Alisma plantagoaquatica in removing nitrogen (N) from farmland wastewater. P. cordata showed fastest rate N removal, followed by A. plantagoaquatica, whereas that calamus was slowest. achieving a greater TN reduction soil than calamus. demonstrated highest adsorption capacity, 32.6% 392.1% higher respectively. The p...

• Some O horizons showed higher nitrification rate than mineral horizons. Both total N and pH were positively correlated with in horizon. Nutrient richness litters supported active Nitrification horizon increased along a threshold of 5.5–6.0. High nitrate leaching has been observed from the some tropical forests; however, drivers high production (active nitrification) these have not yet identif...

Urethanes have marked physiological activity in plants and animals. Lefevre (1939) found that phenyl urethane affects wheat germination, and subsequently Templeman and Sexton (1946) showed that a variety of urethanes suppress the germination of wheat and oats without affecting charlock. The most active urethanes (for example, isopropylphenylcarbamate;ethylphenylcarbamate) are effective at a con...

Marshall, K. C. (Cornell University, Ithaca, N. Y.) and M. Alexander. Nitrification by Aspergillus flavus. J. Bacteriol. 83:572-578. 1962.-Aspergillus flavus has been shown to produce bound hydroxylamine, nitrite, and nitrate when grown in peptone, amino acid, or buffered ammonium media. Free hydroxylamine was not detected in these cultures, but it was found in an unbuffered ammonium medium in ...

Nitrogen (N) saturation is an environmental concern for forests in the eastern U.S. Although several watersheds of the Fernow Experimental Forest (FEF), West Virginia exhibit symptoms of N saturation, many watersheds display a high degree of spatial variability in soil N processing. This study examined the effects of temperature on net N mineralization and nitrification in N-saturated soils fro...