Nitrogen uptake

Variability in Plants, Nitrogen Uptake and Environmental Factors... 

Marschner H. Mineral Nutrition of Higher Plants, Academic Press, London, 1995. S. A. Barber and J. H. Cushman, Nitrogen uptake model for agricultural crops, Moiieling Waste Water Renovation—Land Treatment (I. Iskander, ed.), Wiley In-terScience, New York, 1981. pp. 382-404. 

Tolley MD, DeLaune RD, Patrick WH. The effect of sediment redox potential and soil acidity on nitrogen uptake, anaerobic root respiration, and growth of rice (Oryza saliva). Plant Soil. 1986 93 323-331. 

Nutrient concentration has a marked seasonal variation in the middle Ebro. Nutrient loads transported by the river are relevant during the high flow season (December-April), while nitrate inputs from agriculture can also be relevant. In this period, crop fertilization is carried out, precipitation is higher, and plant nitrogen uptake is lower [37], Although nutrient loads are high, dilution causes NO3 and... 

Nutrient uptake. Nutrient uptake includes base cation uptake (BCU) and nitrogen uptake (Nu). BC uptake assigns annual average uptake of Ca2+, Mg2+ and K+. The data represent an annual net uptake in keq/ha/yr and storage in stems and branches calculated over rotation. This includes the nutrients in the biomass compartments that are expected to be removed from the site at harvest. 

Therefore, it is not feasible to estimate the quinone content from the nitrogen uptake. 

De Bruin and van der Plas (79) also used hydroxylamine in an attempt to identify carbonyl groups. It is not stated whether this reagent was used as free base or as a salt. The considerable nitrogen uptake was very nearly the same as on reaction with ammonia in methanol. Perhaps ammonium salts had been formed in both reactions. The same authors found a pronounced reduction with TiClj which exceeded by far the extent of all other reactions. The TiClj reaction gave easily reproducible results. 

The nitrogen uptake is easily determined by the Kjeldahl method. 

Since the number of free radicals calculated from the dilference in nitrogen uptake (1.13 102 /gm) agreed well with the number of unpaired electrons as determined by e.s.r. (0.80-10 /gm), the aroxylic structure seemed very likely. The reaction of oxidized carbon black with styrene can be explained on this basis 102). 

Nitrogen uptake that results in the formation of new biomolecules is termed an assimilation process, such as assimilatory nitrogen reduction. The processes that result in the release of DIN into seawater are referred to as dissimilations, such as dissimi-latory nitrogen reduction. An example of the latter is denitrification, in which nitrate and nitrite obtained from seawater serve as electron acceptors to enable the oxidation of organic matter. This causes the nitrate and nitrite to be transformed into reduced species, such as N2O and N2, which are released back into seawater. 

Kirk GJD, Kronzucker HJ. 2000. Nitrogen uptake by rice roots. In Kirk GJD, Oik DC, eds. Carbon and Nitrogen Dynamics in Flooded Soils. Manila International Rice Research Institute, 147-162. 

Kirk GJD, Solivas JL. 1997. On the extent to which root properties and transport through the soil limit nitrogen uptake by lowland rice. European Journal of Soil Science 48 613-621. 

Peng S, Cassman KG. 1998. Upper thresholds of nitrogen uptake rates and associated nitrogen fertilizer efficiencies in irrigated rice. Agronomy Journal 90 178-185. 

Vohnik M et al.. The inoculation with Oidiodendron mains and Phialocephala fortinii alters phosphorus and nitrogen uptake, foliar C N ratio and root biomass distribution in Rhododendron cv. Azurro, Symbiosis 40 87—96, 2005. 

Figure 5. Crop Response to Weed Presence, left, and Relative Nitrogen Uptake by Corn, right. Closeness of the vertical lines indicates the relative possibility of competition for N being a factor in crop yield reduction.

Figure 11.9 Effect of carbon contents of Ti samples on the nitrogen uptake.

Figure 11.7 Effect of nitrogen pressure on nitrogen uptake of diluted or undiluted Ti + 0.5 C...

The enhanced nitrogen uptake by titanium in the presence of carbon... 

Because of these, and other mainly practical implications, an exploratory study was recently undertaken (9.) to provide somewhat more detailed information about nitrogen uptake from air by zeolite NaA in a range of ambient temperatures than was currently available (5., 10, 11, 12, 13), and to assess the influ-... 

Nitrogen uptakes were measured at between 10 and 16 pres-... 

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