An assessment of abundance and biological indices of Polychaetes in intertidal zone of Tis Coast - Chabahar Bay

Polychaete worms with high species richness and diversity play a key role in the water food chain. In this research polychates of the intertidal zone of Tis coast in Chabahar bay were studied. Sampling was conducted over a period of one year, from summer to winter 2013 and during four seasons by 50 cm×50 cm quadrats. Twenty two families and 30 genera and 4 species were identified polychaetes.The dominant species of polychaetes were identified: Prionospio sp., Nepthys spp., Scoloplos spp., Spio sp., Ophelia sp., Aphelochaeta sp., Armandia leptocirris. Polychaetes were the most common in winter with 305 Ind.m and autumn with 89 Ind.m is the minimum frequency. Statistical analysis by two-way ANOVA showed significant differences (P>0.05) between the abundance of polychaetes in the year seasons. The species diversity and richness with values 3.6 and 0.88 in winter and the level of environmental integrity in the spring and autumn with value 0.63 and 3.11, respectively, were the highest dominance. The third station with mean 3.29 in four seasons had the highest Shannon index, which reflects the greater diversity of polychaetes in this station. The results showed that this area is very rich in terms of density and diversity of polychaetes. The result obtained from this study could examine the status of contamination by comparing records.