Nutrient provinces in the sea: Concentration ratios, reaction rate ratios, and ideal covariation

Nutrient and carbon removal ratios and #uxes in the Ross Sea, Antarctica

Net community production (NCP) and nutrient de"cits (Def(X)) were calculated using decreases in dissolved CO 2 and nutrient concentrations due to biological removal in the upper 200m of the water column during four cruises in the Ross Sea, Antarctica along 76330@S in 1996 and 1997. A comparison to excess dissolved and particulate organic carbon showed close agreement between surplus total organ...

International Comparison Of Concentration Ratios

Approximating the Distributions of Singular Quadratic Expressions and their Ratios

Noncentral indefinite quadratic expressions in possibly non- singular normal vectors are represented in terms of the difference of two positive definite quadratic forms and an independently distributed linear combination of standard normal random variables. This result also ap- plies to quadratic forms in singular normal vectors for which no general representation is currently available. The ...

N:p Ratios in Estimating Nutrient Limitation in Aquatic Systems

The relative concentrations of N and P have been used to estimate which of these nutrients is limiting the growth of algae in aquatic systems. The approach is simple and easy to use provided that there are data on N and P concentrations. Yet, interpretation of the results should be done with caution as the N:P ratio may not correctly indicate the limiting nutrient of the system. The approach ha...

The relative merits of risk ratios and odds ratios.

When a study outcome is rare in all strata used for an analysis, the odds ratio estimate of causal effects will approximate the risk ratio; therefore, odds ratios from most case-control studies can be interpreted as risk ratios. However, if a study outcome is common, the odds ratio will be further from 1 than the risk ratio. There is debate regarding the merits of risk ratios compared with odds...