Wavelet and Statistical Analysis of Dissolved Oxygen and Biological Oxygen Demand of Ramganga River Water

Abstract

Ramganga river is the main tributary of holy river Ganga and navigates through various cities of Uttarakhand and Uttar Pradesh of India. Its water quality is very important because a lot of population is directly connected to this river. Wavelet transforms is a new analytical tool to analyze non-stationary signals/data because it captures the localized time frequency information of a signal. In wavelet transforms, the Approximation gives the low frequency terms and average behaviour of any data, while Detail gives the high frequency terms and differential behaviour of any data.  The trend represents the slowest part of the signal and corresponds to the greatest scale value. As the scale increases, the resolution decreases, producing a better estimate of the unknown trend of the signal. The dissolved oxygen and biological oxygen demand data of station Kannauj, Uttar Pradesh from October 2015 to June 2020 are studied and processed by Haar wavelet transforms. The statistical parameters like skewness, kurtosis and correlation coefficient are determined and discussed. The strong agreement between wavelet analytical and statistical results is obtained.