Recent studies have shown that macroinfaunal species richness of exposed sandy beaches increases from reflective to dissipative conditions. To analyse if this trend is affected by sampling strategies (primarily area sampled), we compared results from surveys carried out in different beach types of South Africa, Australia and Chile. Total area sampled in those surveys was 4.5 m2. The percentage of species predicted for each beach increased in relation to an increase in total sampling area. Only at a total sample area of 4 m2 were most (>95%) of the species present collected. Sampling areas of 1 m2 and 2 m2 result in average underestimations of nearly 40% and 20% of the species, respectively. Beaches harbouring the highest number of species (the most dissipative ones) need to be sampled more extensively to collect most of the species, as compared with beaches having lower species richness. A bibliographic survey showed that most of the studies carried out on sandy beaches have been based upon sampling areas considerably smaller than 4 to 4.5 m2, suggesting that in many of the studies the sandy beach macrofauna was undersampled.
Sandy beach macroinfauna . Species-area relationships
Full text in pdf format |
Previous article |