Comparative analysis of time-scaling properties about water pH in Poyang Lake Inlet and Outlet on the basis of fractal methods

摘要

Detrended fluctuation analysis (DFA) and multifractal methods are applied to the time-scalingnproperties analysis of water pH series in Poyang Lake Inlet and Outlet in China. The results shownthat these pH series are characterised by long-term memory and multifractal scaling, and thesencharacteristics have obvious differences between the Lake Inlet and Outlet. The comparisonnresults suggest that monofractal and multifractal parameters can be quantitative dynamicalnindexes reflecting the capability of anti-acidification of Poyang Lake. Furthermore, we investigatednthe frequency-size distribution of pH series in Poyang Lake Inlet and Outlet. Our findings suggestnthat water pH is an example of a self-organised criticality (SOC) process. The results show thatnit is different SOC behaviours that result in the differences of power-law relations between pHnseries in Poyang Lake Inlet and Outlet. This work can be helpful to improvement of modellingnof lake water quality.