Base-budgeting approach

An important benefit of the isotopic approach is that below-ground biomass values are not required. The 13C natural abundance isotopic carbon budget approach is based on C3 plants having lower 13C value than C4 plants (Ehleringer 1991 Clay et al. 2006) and that the signatures can be tracked by placing C3 plant residue into a soil derived from C4 plants or vice versa. In these calculations, several definitions are needed. These definitions include... 

Allmaras et al. (2004) developed a C-budgeting approach based on combining experimental and isotopic techniques. The data needed to use calculations derived by Allmaras et al. (2004) required that the experiment contain com stover harvested and removed treatments. These calculations assume that the removal of above-ground biomass will not influence the sequestering of below-ground biomass. The SOC derived from com stover (sSOC) is calculated with the equation ... 

One of the key concerns of analytical science is how good are the numbers produced . Even with an adequately developed, optimised and collaboratively tested method which has been carried out on qualified and calibrated equipment the question remains. Recently it has become fashionable to extend the concepts of the physical metrology into analytical measurements and to quantify confidence in terms of the much more negative uncertainty.It is based on the bottom-up principle or the so called error budget approach. This approach is based on the theory that if the variance contributions of all sources of error involved in analytical processes then it is possible to calculate the overall process... 

The direct recall costs are calculated following the partial budgeting approach. A partial budgeting is based on the principle that a small change in the organization of a business, or in this case the supply chain, will have one or more of the following effects eliminate or reduce some costs, eliminate or reduce some returns, cause additional costs to be incurred and cause additional returns to be received. The net effect will then be the sum of positive financial impact minus the sum of negative financial impact (Dijkhuizen and Morris, 1997). 

Nilsson (1986b) calculated critical loads based on a "proton budget" approach. The critical load is calculated by ensuring that the total input rate of hydrogen ions (H J is less than or equal to the weathering rate (WR) of base cations ... 

Evolution in telescope making since the Palomar has not been limited to the area of optical production. The alt-azimuthal mount has become the established solution since the Bolshoi 6 m telescope, for its superior mechanical performance and the compact, cost-efficient enclosure design it allows. Better understanding of the properties of atmospheric turbulence allowed a more accurate characterization of a telescope properties, a more balanced approach towards specifications and error budgeting and a better understanding of the utmost importance of site selection. Any ground-based telescope of appreciable size will be primarily limited by the effect of atmospheric turbulence, not to mention the proportion of photometric nights allowed by weather conditions. 

As the uncertainty of the mean is now related to the mass used for analysis and it is based on a careful evaluation of the element distribution in the material, this approach could help to evaluate further the total uncertainty budget for various analytical techniques as is required in accreditation and certification campaigns. 

An alternative approach is to combine models with field measurements to assist in developing carbon budgets (Huggins et al. 1998). Clay et al. (2005) used first-order models to calculate the amount of residue returned to the soil from C3 and C4 plants over an 8-year period. Based on the mineralization rates and when the C3 and C4 residues were returned, the 813C signature of non-harvested biomass was determined. Based on the rates, carbon turnover, the amount of SOC mineralized, and the amount of fresh biomass incorporated into the SOC over an 8-year period were determined. 

Alternatively, interlaboratory consensus values based on a range of different methods are used to try to address systematic effects. Such approaches leave open the question concerning traceability, or how closely the certified value agrees with the true value. The establishment of traceability to SI requires the use of primary methods, such as isotope dilution mass spectrometry, or the use of other well understood and validated methods, where any systematic effects have been fully evaluated and corrected for. The uncertainty budget must include appropriate allowance for any suspected residual... 

Design estimate (budget authorisation estimate or scope estimate) based on a semi-detailed analysis. This approach incorporates a mixture of different methods with probable accuracy within +15/20%. 

An alternative approach that has been used is to construct an atmospheric mass budget based on measurements of DMS in air and water olf Cape Grim, Australia in combination with an atmospheric model to estimate the air-sea flux of DMS (Gabric et al., 1995). Their results were consistent with a parametrization of with U based on deliberate tracers (Liss and Merlivat, 1986) but somewhat lower than the " C-derived values (see Section 6.03.2.4.1). 

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