Study the diversity and seasonal variations of endangered fishes, plankton and benthos in Kanchan river of Dinajpur

Authors : Akmrohul AMİN, Mahamud ALAM, Muhammad BADRUZZAMAN, Shafiullah ABBUS

Pages : 13-20

View : 18 | Download : 11

Publication Date : 2019-04-15

Article Type : Research Paper

Abstract :This research work was carried out from February to June, 2018 to monitor the present status of endangered fishes, productivity and overall health status of Kanchan river situated in Dinajpur district. Water and sediment samples were collected twice in a month during the study period from the selected five different sampling sites along with required information about the availability of threatened fishes. The findings noted over 28 available threatened fish species in Kanchan river including several commonly available threatened fishes insert ignore into journalissuearticles values(Endangered: Acanthocobitisbotia, Somileptesgongota, Botiadario, Botialohachata, Bariliustileo, Barilusbengalensisetc.; Critically endangered: Channabarca, Labeonandina, Clupisomagaruaetc.); which are very rear in nationwide. Common planktonic flora and fauna of this riverine ecosystem were also identified. In the river several phytoplankton insert ignore into journalissuearticles values(Asterionella sp., Tabellaria sp., Clostridium sp. etc.); and zooplankton insert ignore into journalissuearticles values(Brachionus sp.); were monitored as season specific. Abundance of plankton were analyzed statistically significant insert ignore into journalissuearticles values(p <0.05); in different seasons. Plankton counting detected comparatively lower insert ignore into journalissuearticles values(23,000 per liter); and higher insert ignore into journalissuearticles values(39,000 per liter); numbers in the month of February and June, respectively. The observed benthic fauna of Kanchan river possessed 22 species of macro-benthos from different groups. Monitored minimum temperature insert ignore into journalissuearticles values(21.5 ºC); was recorded in the month of February and it was maximum in the month of June insert ignore into journalissuearticles values(30.5 ºC);. These results suggested that productivity indicators insert ignore into journalissuearticles values(availability of planktonic flora and fauna including benthos); were better in the early monsoon season than the pre-monsoon season. Similarly, better ecosystem health insert ignore into journalissuearticles values(temperature, dissolve oxygen and availability of plankton); was also observed in early monsoon season. Seasonal variations of water temperature and dissolved oxygen were visualized significant insert ignore into journalissuearticles values(p <0.05);. Finally, this study findings recommended to stop all manmade interventions for the better health of this riverine ecosystem as well as to take necessary actions for conserving the commonly available endangered and critically endangered fishes of Kanchan river.
Keywords : diversity, seasonal variation, endangered fish, plankton, Kanchan River