Sediment properties and analysis
The variation of sediment chemical and physical characteristics was
depicted in the figure 3. Sand and clay contents of sediments showed
large variations in comparison with silt. The average EC of sediments
was 0.42 dS m-1 suggesting that the water quality of
rivers is appropriate. The OM content of sediments was significantly
different, and varied from 0.56 to 5.56 with average of 1.76. The
average percent CCE and ACCE of sediments were 15.03 (2.50-23.75) and
2.08 (0.54-3.86), respectively (figure. 3).
To recognize the physico-chemical properties and sediment that controls
the variability of the data, the provided diagram shows the results of a
principal component analysis (PCA) of sediment characteristic variables
(figure 4). The first and second components together represent 79.3% of
the variation. First PC is mainly determined by ACCE, clay, and silt,
and is negatively dependent on Vfs, D50 and Sand. This implies that
correlated variables control variation in the data set. The second
component showed strong negative correlations with pH and CCE,
negatively correlated with OM, and EC. There were large differences
between observations from various samples (Figure 4).