Correlation Study for Assessment of Water Quality and its Parameters of Kushiyara River, Sylhet, Bangladesh

Tajmunnaher , Dr.Muhammad Aktarul Islam Chowdhury

This research aims to analyze correlation between surface water quality parameters of River Kushiyara, Sylhet Division, Bangladesh on the basis of physico-chemical parameters such as Temperature, P^H, DO (Dissolved Oxygen), BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), TS (Total Solids), TDS (Total Dissolved Solids) and SS (Suspended Solids). Pearson’s correlation coefficient (r) is determined using correlation matrix to identify the highly correlated and interrelated water quality parameters. To test the significance of the pair of parameters p-value is carried out. There is a relationship between variables which shows that one variable actually causes change in another variable. In rainy season the highest significant correlation is found between COD & TS, TS & TDS, BOD & COD and BOD & SS. In winter season the highest significant correlation is found between TS & TDS, TS & SS, TDS & SS and Temperature & P^H. The DO showed negative correlation with most of the parameters and in winter season the DO show negative correlation with all other parameter more or less, which reveals that when other water quality parameters increase the DO value decreases.