in most semiarid and arid areas, fresh water shortage compels managers to use low quality water sources with high salinity to irrigate turf and landscape. recent research has noticed that management of nitrogen fertilization can alleviate salinity effects on plants. this greenhouse sand culture experiment was conducted in order to investigate morphological and physiological responses to salinit...

Nitrous oxide (N2O) is a potent greenhouse gas. In North China, vegetable fields are amended with high levels of N fertilizer and irrigation water, which causes massive N2O flux. The aim of this study was to determine the contribution of microbial processes to N2O production and characterize isotopic signature effects on N2O source partitioning. We conducted a microcosm study that combined natu...

Homologues of the amtB gene of enteric bacteria exist in all three domains of life. Although their products are required for transport of the ammonium analogue methylammonium in washed cells, only in Saccharomyces cerevisiae have they been shown to be necessary for growth at low NH4+ concentrations. We now demonstrate that an amtB strain of Escherichia coli also grows slowly at low NH4+ concent...

Compensation points for gaseous exchange of ammonia (NH3) between stomata and the atmosphere were determined in an oilseed rape (Brassica napus) canopy by analysing the concentrations of NH4+ and H+ in leaf apoplastic solution. This bioassay approach was applied for the first time in the field, allowing the first intercomparison with compensation points derived from micrometeorological measurem...

The excretion of nitrogenous waste products in the form of ammonia (NH3) and ammonium (NH4 (+)) is a fundamental process in aquatic organisms. For mytilid bivalves, little is known about the mechanisms and sites of excretion. This study investigated the localization and the mechanisms of ammonia excretion in mytilid mussels. An Rh protein was found to be abundantly expressed in the apical cell ...

The permeation of monovalent cations through the cGMP-gated channel of catfish cone outer segments was examined by measuring permeability and conductance ratios under biionic conditions. For monovalent cations presented on the cytoplasmic side of the channel, the permeability ratios with respect to extracellular Na followed the sequence NH4 > K > Li > Rb = Na > Cs while the conductance ratios a...

The gas sensor based on pristine graphene with conductance type was studied theoretically and experimentally. The time response of conductance measurements showed a quickly and largely increased conductivity when the sensor was exposed to ammonia gas produced by a bubble system of ammonia water. However, the desorption process in vacuum took more than 1 h which indicated that there was a larger...

OBJECTIVE The purpose of this study was to identify values for net acid base excretion (NABE) which are significant indicators of the acid-base equilibrium in pregnant and young ewes and to show its relationship with other parameters (base, acid, ammonium [NH4], base-acid quotient, sodium [Na], potassium [K], calcium [Ca]) in ovine urine. In contrast to dairy cows, data are rare on these parame...

Ammonia is one of the most important contaminants impairing the quality of water resources. When this is considered along with the fact that the global demand for nitrogenous fertilizers is in constant rise, the need for recovery as well as removal of nitrogen is well justified. Crystallization of N and P in the form of struvite (MgNH4PO4 6H2O), which is a slow releasing and valuable fertilizer...

Citation: Atkins JF, Moloney CL, Probyn TA and Bernard S (2016) In situ Measurements and Model Estimates of NO3 and NH4 Uptake by Different Phytoplankton Size Fractions in the Southern Benguela Upwelling System Front. Mar. Sci. 3:194. doi: 10.3389/fmars.2016.00194 In situ Measurements and Model Estimates of NO3 and NH4 Uptake by Different Phytoplankton Size Fractions in the Southern Benguela Up...