Revista de la Sociedad Entomológica Argentina
Print version ISSN 0373-5680
BASUALDO, Carola V.. Choosing the best non-parametric richness estimator for benthic macroinvertebrates databases. Rev. Soc. Entomol. Argent. [online]. 2011, vol.70, n.1-2, pp. 27-38. ISSN 0373-5680.
Non-parametric estimators allow to compare the estimates of richness among data sets from heterogeneous sources. However, since the estimator performance depends on the species-abundance distribution of the sample, preference for one or another is a difficult issue. The present study recovers and revalues some criteria already present in the literature in order to choose the most suitable estimator for streams macroinvertebrates, and provides some tools to apply them. Two abundance and four incidence estimators were applied to a regional database at family and genus level. They were evaluated under four criteria: sub-sample size required to estimate the observed richness; constancy of the sub-sample size; lack of erratic behavior and similarity in curve shape through different data sets. Among incidence estimators, Jack1 had the best performance. Between abundance estimators, ACE was the best when the observed richness was small and Chao1 when the observed richness was high. The uniformity of curves shapes allowed to describe the general sequences of curves behavior that could act as references to compare estimations of small databases and to infer the possible behavior of the curve (i.e the expected richness) if the sample were larger. These results can be very useful for environmental management, and update the state of knowledge of regional macroinvertebrates.
Keywords : Richness estimation; Neotropical streams; Environmental management.