Investigation on the effects of some environmental factors on morphology of Baetis vernus in Karaj River

Abstract

Environmental factors strongly contribute to shaping the morphology of organisms. The present study mainly aims to examine how some physical factors in a habitat influence morphological variations in Baetis vernus along the Karaj River. Sampling was conducted using a kick net sampling device with a mesh size of 500 μm at 10 sampling sites (three replicates) by recording 11 environmental variables in autumn (2018) and spring (2019). The species was identified through gender classification (male and female). Graticule was used to measure 42 morphological properties of 30 (male and female) samples identified at each site. Following the statistical analysis of the data, the results showed significant changes in environmental factors such as temperature (autumn), depth (spring), and elevation (autumn and spring) (p<0/05). In addition, changes in environmental factors such as temperature, width, and discharge in autumn and temperature, water flow velocity, discharge, salinity, and EC in spring influenced the morphological variations. The changes in these factors seem to contribute to morphological variations in B. vernus (changes in moving and non-moving traits with habitat changes) along the Karaj River by affecting the habitat conditions. the analyses of gender-related morphological variations in B. vernus showed no difference between the male and female species in terms of these traits.

Keywords

• ecosystem
• morphological variation
• baetidae
• ephemeroptera