Effect of Fish Cage Culture on Water Quality: A Case Study of Chi River and Yang River, Roi Et Province

Abstract

This study was aimed to determine effect of fish cage culture on water quality of Chi River and Yang River in Roi Et Province. The water samples were collected from each river; at the fish cages, 500 m upstream and 500 m downstream adjacent to the cages. The samples were collected during different seasons of the year; April 2007, July 2007, October 2007 and January epresenting the hot. early rainy, fate rainy and cool2008, seasons, respectively. Physiochemical properties of the water were analyzed either in the field instantly or in the laboratory afterward. The results showed that comparing between Chi River and Yang River, some parameters on water quality; sediment, pH and organic matter, were significant dIfference (p < 0.05), however, on some parameters; total nitrogen (TN) and total phosphorus (TP) were not. Furthermore, comparing among different seasons. these parameters; sediment. pH, TN, TP and organic matter, were also significant difierent. Then again, comparing among sampling stations; pH and % organic matter were different, except the sediment, TP and TN. The results indicated that fish cage culture did cause some changes in some parameters of the water quality Yet, those changes were still within the standard. Thus, it can be concluded that the fish cage culture in Chi River and Yang River had some impacts but were not giving any significant impact toward the water quality of the rivers.