Wavelet and statistical analysis of river water quality parameters

Statistical and wavelet analysis of water quality parameters COD (chemical oxygen demand), BOD (biochemical oxygen demand), DO (dissolved oxygen), WT (water temperature), AMM (free ammonia), TKN (total kjeldahl nitrogen), TC (total coliform), FC (fecal coliform) and pH (potential of hydrogen) monitored at Nizamuddin bridge-mid stream (Delhi) of Yamuna River in India have been studied. It has been observed that COD is highly correlated with BOD, AMM and TKN. Daubechies wavelet at level 5 (Db(5)) have been calculated for each water quality parameters as it gives the finer scale approximation and decomposition of each water parameters. Wavelet decomposition and approximation using Db(5) of each parameters presented in seven parts namely s, a(5), d(1), d(2), d(3), d(4) and d(5) where "s'' represents signal or raw data; low frequency part "a(5)'' gives an approximate of signal at level 5; high frequency parts d(1), d(2), d(3), d(4) and d(5) contains the detail of "s'' at different levels respectively. (C) 2013 Elsevier Inc. All rights reserved.