Strain-specific degradation rates were fed into the Martin curve, the standard model of how carbon flux fades with depth. Faster degradation near the surface means less carbon reaching the deep ocean.
Bacterial enzyme-secretion phenotype governs carbon-flux attenuation. Normalised particulate-organic-carbon flux F(z)/F(z₀) versus depth, predicted by the Martin curve F = (z/z₀)−b. Strain-specific degradation rates from ADE-I were converted to flux-attenuation coefficients b: broadcaster-colonised particles (13B01) attenuate faster (b = 0.95) than aggregator-colonised particles (mean b = 0.78), bracketing the classic Martin value (b = 0.86). At 1000 m, broadcaster-colonised particles retain only ~11% of initial carbon versus ~17% for aggregator-colonised particles. This is the broadcaster paradox: the faster degraders, fitter as individual bacteria, return carbon to the upper ocean before it can be sequestered at depth. Curves draw in on view; in a static preview the final state is shown.