Quantifying macroinvertebrate taxon richness and abundance in open and forested pool complexes in the Sutherland Flows

Abstract

1. The aquatic macroinvertebrates of two pool complexes, one open and one forested, in the Sutherland Flows containing temporary, drought sensitive and permanent pools were sampled to establish the most economical sampling for future investigation into the effects of afforestation. 2. Given the variation in pool type and size within each complex, (a) an estimate of the average number of taxa per pool of each type was needed to compare pools of different types, (b) the total number of taxa found in each pool type was needed to allow comparison between sites. 3. Thirty specimens from each pool established the average number of taxa per pool and showed that permanent pools had a higher taxon richness than temporary pools. 4. Four hundred and fifty specimens (and therefore 15 pools with 30 specimens each) were needed to give an estimate of the total number of taxa per pool type. However, the number of samples in some categories was insufficient to allow comparisons to be made between sites and rarefaction was used to make baseline comparisons. 5. Rarefaction suggests that at both sites the permanent pools had highest taxon richness. Rarefaction also indicated there may be slightly higher total invertebrate taxon richness in each pool type at the forested site. Copyright © 1999 John Wiley & Sons, Ltd.