A trophic diversity index for presence-absence food data |
| |
Authors: | Carlos M. Herrera |
| |
Affiliation: | (1) Estación Biológica de Doñana, Paraguay 1-2, Sevilla-12, Spain |
| |
Abstract: | Summary An index to assess trophic diversity from presence-absence food data is proposed. The index is computed according to the expression , where the 's are the frequencies of occurrence of the various prey categories. The upper and lower limits of D are derived. A test of the reliability of D was carried out by comparing D and H (Shannon's information function) values obtained from a set of twenty-three food analyses from vertebrate animals. Results show that, although a significant correlation exists between D and H, only a small fraction of H-variation is explained by D-variation. D contains two kinds of information, one referred to species richness and another relative to the degree of between-samples heterogeneity. The former is shared in common with H and this presumably explains the fairly weak correlation found between both measures. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|