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Eric N. Powell George M. Staff Robert J. Stanton Jr W. Russell Callender 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2001,34(2):97-118
We evaluate onshore-offshore trends in age-frequency distributions and trophic transfer efficiencies using 11 modern death assemblages off the Texas coast. Trophic transfer efficiencies within trophic levels offer little insight over that achieved by a size-frequency distribution. Production/biomass ratios will always be 1 in the fossil record. Within trophic-level estimates of paleogrowth efficiency, the ratio of paleoproduction to paleoingestion (Piglt/Iilt where i indicates the ith trophic level and lt indicates the time-averaged value) follow the expected ecological trend precisely in that paleogrowth efficiency is consistently higher in primary consumers than in predators in all 11 death assemblages. Paleoutilization efficiency, the ratio of predator paleoingestion to prey paleoproduction, I2lt°/P1glt°, may provide information on the degree of bias in the preservation of primary (1 °) and secondary (2 °) consumer trophic groups. I2lt°/P1glt° fell below 0.1 in most cold-seep and bay assemblages, indicating a large surplus of primary consumers. In sharp contrast, I2lt°/P1glt° 相似文献
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