The dependence of heterotrophic consumption and C accumulation on autotrophic nutrient content in ecosystems

Primary producers with high nutrient contents typically exhibit high herbiv ory rates and fast decomposition rates. These tendencies, however, have not been generalized across ecosystems with contrasting herbivore characterist ics and abiotic properties. Here we demonstrate that ecosystem types domina ted by richer autotrophs (i.e. higher nutrient contents) are subject to hig her rates of herbivory and decomposition in spite of differences in herbivo re characteristics and environmental conditions. We further show that, as a result of these tendencies, ecosystems with richer autotrophs accumulate l ess carbon. These results identify autotrophic nutrient content as a main c ontrol of heterotrophic consumption and carbon accumulation in ecosystems. They also provide a basis to evaluate changes in these ecosystem properties following anthropogenic eutrophication.