Assimilates distribution

Davies, W.J. Sharp, R.E. (1981). The root a sensitive detector of a reduction in water availability In Mechanisms of Assimilate Distribution and Plant Growth Regulators, ed. J. Kralovic, pp. 53-67. Prague Slovak Society of Agriculture. 

C. P. P. Reid. Assimilation, distribution and root exudation of C by ponderosa pine. seedlings under induced water stress. Plant Phy.siol. 54 44 (1974). 

K.J. Treharne, Hormonal Control of Photosynthesis and Assimilate Distribution , in Chemical Manipulation of Crop Growth and Development ed. J.S. Mclaren, Butterworth Scientific, 1982, pp. 55-66. 

Bichele I. Moldau H. and Ross Yu. (1980). Sub-model for the Assimilation, Distribution, and Vegetation Growth under Condition of Water Deficit. Tartu Astrophysical Observatory, Report A-5, Tartu, 22 pp. [in Russian],... 

General mechanisms of uptake, assimilation, distribution and transport have been suggested by a number of authors (Bowling, 1976 Baker, 1983 Marschner, 1983 Az-piazu et al., 1986 Davies and Jeffcoat, 1990 Fergusson, 1990 Streit and Stumm, 1993). 

In studying the impacts of pollutants on wildlife, the wildlife toxicologist evaluates exposure and effects, and determines the mechanisms involved in the assimilation, distribution, and influence chemicals have on specific cells or biological processes that effect the individual, population, or community of organisms living in the area where a pollutant occurs. In addition to evaluating the effects of pollutants on wild species, wildlife toxicologist also have used wild... 

Following exposure to SO2 under certain conditions, inhibition of assimilate distribution has been observed without changes in photosynthesis(8,9).This suggests that the primary effect was on translocation. However, alterations in the pattern of growth (not necessarily a reduction in growth) cannot be explained by inhibition of translocation alone, because translocation must be maintained for redistribution of assimilate to occur (10). 

It is well known that chemical compo.sition of rhizosphere solution can affect plant growth. Particularly, uptake of nutrients may be considerably influenced by the ionic concentration of the rhizosphere solution (40). Despite the difficulty of defining the exact concentration of ions in the rhizosphere surrounding each root (or even root portion), it has been unequivocally demonstrated that plants have evolved mechanisms to cope with the uneven distribution of ions in the root surrounding in order to provide adequate supply of each essential nutrient (41). These mechanisms include expression of transporter genes in specific root zones or cells and synthesis of enzymes involved in the uptake and assimilation of nutrients (40,43). Interestingly, it has been shown that specific isoforms of the H -ATPase are expressed in the plasma membrane of cell roots it has been proposed that the expression of specific isoforms in specific tissues is relevant to nutrient (nitrate) acquisition (44) and salt tolerance (45). 

Recently, pulse labeling has frequently been applied to determine the fate of carbon in crops such as barley and wheat and the losses from roots and subsequent microbial transformations. In general, the results indicate that 15-25% of the net " C assimilation is transferred to the roots and that there are seasonal differences in the distribution of assimilated carbon. Meharg and Killham (25) measured the C distribution in perennial ryegrass (L perenne). At 8 days after the pulse with... 

Environmental organic pollutants may be degraded depending on their toxicity, solubility, distribution constant Kow because physical properties of hydrophobic chemicals may affect the solubility and therefore the amount of organic carbon available in the aqueous phase for microbial assimilation and further metabolism (Schwarzenbach and Westall 1981). Chemicals are subject to volatilization and such loss is not assessed in most of the study except for physical transformation and material balance purposes. Polyaromatic hydrocarbons (PAHs) are known to volatilized during incubation even with capping and more then 40% of the initial chemicals could be found lost (Yin and Gu, unpublished data). When proper control was not included and such... 

The refinements made to the entire model setup include a higher model resolution, the implementation of most recent ECH AM, MPIOM and HAMOCC versions, the usage of assimilated satelhte data for surface phytoplankton distribution, and the usage of a more realistic description of sinking organic matter in the ocean. 

The AE methods have been used to determine the effects of different algae as food sources in the bioaccumulation of radiolabelled essential (Co, Se, Zn) and nonessential trace metals (Ag, Am, Cd, Cr) in the mussel Mytilus edulis [94]. Assimilation of essential metals was correlated with carbon assimilation, but not nonessential metals. The distribution of the metal in the alga and the gut passage time in the mussel was found to be important. 

Volume-normalized extinction is plotted in Fig. 11.2 as a function of photon energy for several polydispersions of MgO spheres both scales are logarithmic. For comparison of bulk and small-particle properties the bulk absorption coefficient a = Airk/X is included. Some single-particle features, such as ripple structure, are effaced by the distribution of radii. The information contained in these curves is not assimilated at a glance they require careful study. 

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