Assimilation mean values

DON concentrations of 4-8 pM have been observed in the relatively weak upweUing area off the northwest coast of Spain (Alvarez-Salgado et al., 1999). HUl and Wheeler (2002) reported values of 7 pM DON in upweUed waters off the Oregon coast. These are similar DON concentrations to the open ocean as summarized Table 17.3 of HiU and Wheeler (2002). Some of this DON is upweUed e.g., water at 50 m depth off Oregon had a mean value of 5.98 (HUl and Wheeler, 2002). Another source is from production by phytoplankton as they partition newly assimilated NO3 into particulate nitrogen and DON that is released (Bronk et al., 2006 Wetz and Wheeler, 2003). 

Table 3-5 Mean values for Respiration (R), Production (P), and Assimilation (A) in kj/m year for different groups of animals ...

R being the relative photosynthesis, determined empirically, for the appropriate value of surface radiation, k the extinction coefficient per metre of the water, C the amount of chlorophyll in g m, and the factor 3.7 a mean value for the assimilation number. Values estimated by this method and those determined by the oxygen technique agreed reasonably well for a number of sea areas in which primary productivity varied by an order of magnitude (Fogg, 1975). 

Suppose the Ni are known and assimilated to their mean value on the plate. Indeed, taking account of the variations of Ni both across the height of the LVM and across the active surface would greatly complicate the calculations without significantly improving the accuracy. In an elementary volume dV, the heat exchanged is ... 

In contrast to the primary production, which is estimated by a wide use of radiocarbon techniques, the methods for calculation of the secondary production are based either on the data for the rate of weight growth at different stages of their lifecycle and their abundance, or on the use of physiological characteristics of the organism such as the daily ration, the proportion of the assimilated food in the ration, and the respiration. The data obtained with these methods allow estimation of the values of production of the main species of copepods and other animals [69]. The mean annual values of the... 

Siderophores are highly specific Fe(III) ligands (formation constants often > 10 ) and are excreted by a wide variety of fungi and bacteria to aid iron assimilation because of the low solubility of Fe + at pH values where most life exists. Siderophores are the most common means of acquisition of iron by bacteria and fungi (Crichton, 1991), and in soil, many different species, including plants, will compete for Fe. Although produced primarily as a means of obtaining iron. 

Carbon can remain in the SOC pool for a long period after its assimilation by vegetation. This means that not all carbon in the SOC pool is in equilibrium with the isotopic composition of the modern atmosphere due to a decrease in the C value of the atmosphere as a result of fossil fuel burning since industrialization (Freidli et al, 1986 Bird et al, 1996). Old carbon will therefore be enriched by up to 1.5%o compared to recent carbon. This terrestrial Seuss effect needs to be considered when calculating the (S C value of CO2 respired to the atmosphere from the SOC pool (Fung et ai, 1997). 

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