Fractal, predictability index and variability in trends analysis of river-water dynamics

Abstract

ABSTRACTStatistical modelling, analysis of physico-chemical parameters chemical oxygen demand (COD), biochemical oxygen demand (BOD), dissolved oxygen (DO), water temperature (WT), free ammonia (AMM), total Kjeldahl nitrogen (TKN), total coliform (TC), fecal coliform (FC) and potential of hydrogen (pH) monitored at the Hathnikund barrage (Haryana) sample site of river Yamuna in India have been studied. It has been observed that water-quality parameters such as COD-BOD, AMM-TKN, WT-pH and TC-FC are positively correlated whereas COD-DO, BOD-DO, TKN-FC and DO-WT are negatively correlated. For water-quality parameters such as pH, AMM, TC and FC no seasonal pattern is observed. Parameters such as COD, BOD, TKN, DO and WT follow a six-month seasonal pattern. All the parameters except DO and WT follow a positive trend for monthly and annual variations. BOD, AMM and TKN have anti-persistence behaviour for both monthly and yearly variations. For parameters COD (+27.83%), BOD (+42.36%), AMM (+49.63%), TKN (+22.71%), TC (+141.80%) and FC (+42.89%) the future trend remains positive with high variability. WT (−7.47%) follows a negative trend with low variation and DO (−17.12%) has a negative trend with lofty variation. Using fractal, predictability index and variability in trend analysis, it is concluded that all parameters, except pH and WT, cross the prescribed limits of WHO/EPA and if the same trend should be followed, then in the future the quality of water shall continuously deteriorate and water may not be fit for drinking, agriculture and industrial use.