III. Results
The bioavailability of metals once introduced to the water and sediments particularly in a river ecosystem are affected by several factors such as pH, siltation and organic matter. Sediments sampled from Butuanon River have pH values consistently neutral across the three sampling stations and registered no significant difference (p>0.05) (Table 1). Both the percentage silt and percentage organic matter follows an increasing trend from upstream to downstream portions The values of percentage of silt registered a significant difference (p