The Biological Assessment of the Samsami River Using the Structure of Benthic Macroinvertebrates (Chaharmahal-o-Bakhtiary Province)

There are different methods for assessing river water quality. One of these methods is to use the large population structure of bulk invertebrates. Accordingly, this study was carried out to evaluate the quality of water of the Smsami River using large invertebrates.

In this study, 7 stations were selected along the 10 km of Samsami River and sampling was done in a one-year period every 45 days. Data were collected as population measurements including total richness, EPT richness, EPT frequency ratio to Chironomidae family, Shannon-Wiener diversity index and biological index in Hallesinof family.

The results of this study included 11 orders and 45 groups (family and sex) of the large invertebrates, the larvae of aquatic insects had the highest diversity and abundance. The maximum and minimum mean of total frequency per square meter during the study period was at station 2, (1694 ± 232.72) and (314.71 ± 13.7) At station 7 respectively. The dominant orders in this study were Ephemeroptera, Trichoptera.

Evaluations showed that in stations 2 and 6, due to the entry of rural wastewater and fish farming, the quality of river water has changed and the frequency and frequency of infected families have decreased and contaminated groups have increased. Based on this, it can be concluded that the use of the measurement of the diversity and abundance of large invertebrates as an indicator of the biological contamination of water is a good way to evaluate the water quality of the river.