Fig. 4

Modified degree of contaminations (mDc) variations in 3 years. a Using this generalized formula to calculate the degree of contamination: mDc = (∑Dc)/n. b Results show the degree of contamination in bottom sediments through different 3 years
Modified degree of contaminations (mDc) variations in 3 years. a Using this generalized formula to calculate the degree of contamination: mDc = (∑Dc)/n. b Results show the degree of contamination in bottom sediments through different 3 years