Phosphorus relationships

In this way, the near-linear chlorophyll-phosphorus relationship in lakes depends upon the outcome of a large number of interactive processes occurring in each one of the component systems in the model. One of the most intriguing aspects of those components is that the chlorophyll models do not need to take account of the species composition of the phytoplankton in which chlorophyll is a constituent. The development of blooms of potentially toxic cyanobacteria is associated with eutrophication and phosphorus concentration, yet it is not apparent that the yield of cyanobacterial biomass requires any more mass-specific contribution from phosphorus. The explanation for this paradox is not well understood, but it is extremely important to understand that it is a matter of dynamics. The bloom-forming cyanobacteria are among the slowest-growing and most light-sensitive members of the phytoplankton. ... 

Hesse, P.R. (1963) Phosphorus relationships in a mangrove-swamp mud with particular reference to aluminium toxicity. Plant and Soil, 19, 205-218. 

It is likely that these low concentrations of leaf phosphorus are limiting for photosynthesis. This is shown in Figure 2, where the photosynthesis/phosphorus relationship is shown for the laboratory studies of Cromer et al. (1993) and Lovelock et al. (1997) and the field studies of Raich et al. (1995) and Raaimakers et al. 

Lolas, G.M. N. Palamidas P. Markakis. The phytic acid—Total phosphorus relationship in barley, oats, soybeans and wheats. Cereal Chem. 1976, 53, 867-871. 

Intuition dictates that reducing nutrient inputs, particularly phosphorus, must reduce the supportable biomass. Relationships show that sustained response cannot be effected before it can be demonstrated (i) that nutrient is exhausted at a lower concentration of algae than the existing maxima and (ii) that in situ recycling is unable to make up the shortfall. 

The dipole moment of tributylpliosphine varies from 1.49 to 2.4 D according to the solvent used. Inductive effects in phosphines have been estimated by comparing the calculated and observed dipole moments, and the apparent dipole moment due to the lone electron pair on phosphorus has been estimated. A method of calculating the hybridization of the phosphorus atom in terms of bond angles is suggested which leads to a linear relationship between hybridization ratio and lone electron pair moment. The difference between experimental and calculated dipole moments for para-substitued arylphosphines, phosphine sulphides, and phosphinimines has been used to estimate mesomeric transfer of electrons to phosphorus. 

Reports of lead-nutrient interactions in experimental animals have generally described such relationships in terms of a single nutrient, using relative absorption or tissue retention in the animal to index the effect. Most of the data are concerned with the impact of dietary levels of calcium, iron, phosphorus, and vitamin D. These interaction studies are summarized in Table 2-12. 

Figure 5.18. Relationship between white phosphorus concentration of the starting solutions and electrical resistivity of resulting doped-Si films. [Reproduced with permission from Ref. 25. Copyright 2007 The Japan Society of Applied Physics.]...

Figure 5.18 shows the relationship between the resistivity and phosphorus concentration of the initial solution for the film formed from various solutions and heated under the same polycrystallizing RTA conditions (750 °C for 5min). As the initial phosphorus concentration increases, the resistivity decreases down to 2.1mQcm. The film formed from a l-wt% postpolymerization addition solution and the film formed from a 0.01-wt% copolymerized solution exhibit almost the same resistivity, which is reasonable since the two films have almost the same amount of phosphorus atoms, as shown in Fig. 5.16. To apply these doped-silicon films to the source and drain regions of poly-Si TFTs, the initial concentration of 0.1-1 wt% will be sufficient in the case of the copolymerized solution for this heating condition.

Finally, we tried to activate dopant atoms using pulsed laser irradiation, which is effective in lowering the process temperature. The light source was a 308-nm XeCl excimer laser, which is a standard source for crystallizing a-Si films used in the LTPS process.19 A test sample of 76 nm thickness, prepared from the copolymerized solution (l-wt% phosphorus, 30-min UV irradiation, 500 °C 2hr annealing), was irradiated using a XeCl laser at various intensities to activate the dopant atoms. Figure 5.19 shows the relationship between the... 

Fig. 4 Redundance analysis (RDA) on phytoplankton communities collected during the surveys of 2005-2006 and their relationship with the environmental variables, such as the Total Phosphorus (PTOT), Water Flow (WATFL), Total Suspended Solids (TSS), ammonia concentration (NH4), nitrate concentration (N03), and conductivity (COND). Acronyms were also used for phytoplankton taxa representation...

Klironomos JN, McCune J, Hart M, Neville J (2000) The influence of arbuscular mycorrhizae on the relationship between plant diversity and productivity. Ecol Lett 3 137-141 Lajtha K, Harrison AF (1995) Strategies of phosphorus acquisition and conservation by plant species and communities. In Hessen H (ed) Phosphorus in the global environment. Wiley, Chichester, UK, pp 140-147... 

Usuda H (1995) Phosphate deficiency in maize. V. Mobilization of nitrogen and phosphorus within shoots of young plants and its relationship to senescence. Plant Cell Physiol 36 1041-1049. doi http //pcp.oxfordjournals.org/cgi/content/abstract/36/6/1041 van der Heijden MGA, Boiler T, Wiemken A, Sanders IR (1998a) Different arbuscular mycor-rhizal fungal species are potential determinants of plant community structure. Ecology 79 2082-2091... 

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