HYDROCHEMICAL INFLUENCE ON FISHERY POTENTIAL OF ONE OF THE MOST POLLUTED RIVERS OF INDIA: KOLONG RIVER, NAGAON, ASSAM

Abstract

Rivers are the priceless blessings for both nature and mankind. Specially, Indian people consider rivers as mother and Goddess. There is a saying that- “Every River of India is as sacred as river Ganga”. The historic Kolong river, the tributary of the mighty river Brahmaputra was once a vibrant river, which is now struggling for pollution. The Central Pollution Control Board of India (2015) has categorized this river under the most polluted rivers of India. Therefore, it is important to analyze the recent hydrochemistry of the polluted ecosystem and identify the root causes of pollution. For commercial utilization of the river, we must know about the ecological strength of it. Though the contribution of the fishery sector of Assam to the State Gross Domestic Product is very high, but due to the lack of proper scientific skills, people are unable to utilize the aquatic resources of the state in commercial purpose. Day by day, pollution in some water bodies is becoming very alarming, but no properly planned measures and means have been taken to compensate the same. This study aimed to explore the significant impact of hydrochemical dynamics on fishery potential of Kolong river. The study was conducted at four different sites (Samoguri, Nagaon town, Jagi bhakatgaon and Mayong Kajalimukh) of the river in four different seasons by following standard guidelines. The study documented the detrimental effect of water pollution in fishery potential of the river, particularly in Nagaon town site. pH and conductivity had significant negative impact on fish abundance. The undesirable values of alkalinity, Phosphate and Dissolve oxygen were recorded. Transparency values also indicated unclear water. As per the study, some important fish species were found to be totally absent in that site. However, presence of 32 different fish species (Critically endangered, Endangered, Nearly threatened) indicated a good sign from conservation point of view.