Solution culture experiments were carried out to study the kinetics at cotyledon stage (11-day-old) and the effect of different NO3/NH4 on NO3 and NH4 uptake at seedling stage (31-day-old) with two cultivars of sugar beet, including Tianyan7 and Tianyan8. NO3 uptake by sugar beet seedlings at cotyledon stage (11-day-old) reached equilibration after 2 hours of adaptation, and NH4 uptake reached ...

The effects of different concentrations of CdCl2 and AlCl3 on NH4+ and NO2? oxidation in an aqueous system were investigated. AlCl3 had no effect on NH4+ removal and its oxidation to NO2?, whereas NO2? disappearance was greatly enhanced by AlCl3. In contrast, CdCl2 delayed removal of NH4+ and its subsequent oxidation to NO2? and also decreased the rate of NO2? disappearance. When compared to th...

fifteen kinds of local wetland plants in taihu lake region of china were investigated on their respective growth conditions, biomass allocations and nutrient uptake capacities. the test plants were cultured in 3 l nutrient solutions for 28 days with nh4 +-n, no3 --n and p concentrations of 38.5, 132.8 and 10 mg/l, respectively. mean species total biomass ranged from 1.2-21.6 g/plant with a...

Two successive lettuce crops were grown in spring 2005 in a completely closed hydroponic system. The ratio of ammonium to total nitrogen (Nr) in the fresh nutrient solution (FNS) introduced into the closed system to compensate for plant uptake was 0, 0.1, 0.2 and 0.3 on amolar basis. In allNr treatments, the concentrations of total N, K, Ca, Mg, P, and micronutrients in the FNS were identical, ...

From extraction experiments and gamma-activity measurements, the extraction constan corresponding to the equilibrium NH4(+)(aq) + 1*Na(+)(nb) <=> 1*NH4(+)(nb) + Na(+)(aq) taking place in the two-phase water - nitrobenzene system (1 = dibenzo-18-crown-6, aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K(ex) (NH4(+),1*Na(+)) = -0.1 +/- 0.1. Further, the stability constant of the...

The reproducible formation of a 3D oxalate based coordination compound of formula (NH4)5[Mn(II)2Cr(III)3(ox)9]·10H2O, with an unusual Mn(II)/Cr(III) ratio, is presented. The original topology of the anionic network leads to antiferromagnetic long-range ordering whereas its guests favour high humidity-dependent proton conductivity.

The present study with young poplar trees aimed at characterizing the effect of O2 shortage in the soil on net uptake of NO3- and NH4+ and the spatial distribution of the N taken up. Moreover, we assessed biomass increment as well as N status of the trees affected by O2 deficiency. For this purpose, an experiment was conducted in which hydroponically grown young poplar trees were exposed to hyp...

NH4 uptake capacity of loblolly pine (Pinus taeda L.) and ponderosa pine (Pinus ponderosa Douglas. Ex Laws.) seedlings that were grown in pots in a phytotron at CO2 partial pressures of 35 or 70 Pa with NH4 + as the sole N source. Kinetics of N-labeled NH4 + uptake were determined in excised roots, whereas total NH4 + uptake and uptake rates were determined in intact root systems following a 48...