Abstract |
Plastic pollution is an emerging threat in the riverine ecosystem that affects the marine
ecosystem. The Philippines, being an archipelago, is heavily dependent on its marine ecosystem.
It is also considered the largest emitter of plastic via rivers. Despite this, limited field studies
have been conducted to validate this finding, which is mainly based on numerical models. In
this study, we determined the prevalence of macroplastics in Pulauan River, Dapitan City by
observing the plastic flux and further comparing the morning and afternoon flux. Macroplastic
collection was also performed to compare the plastic densities of three stream areas: upstream,
midstream, and downstream. Results show that macroplastic flux in the morning (304 items/h)
was significantly higher than in the afternoon (91 items/h). The correlation of macroplastic flux
and flow velocity was determined to be positive 脙聝脗垄脙聜脗聙脙聜脗聯 suggesting that as macroplastic flow velocity
increases, plastic flux tends to increase. Macroplastic collection results showed that upstream
density (0.074 items/m2) is significantly lower than midstream (0.559 items/m2) and downstream
(0.473 items/m2) densities. This shows that the nearer the area is to the river mouth, the more
susceptible it is to plastic litter deposition. The composition of the macroplastic litters observed
and collected was attributed to the influences of human activities (aquaculture, fishing, and
residential) 脙聝脗垄脙聜脗聙脙聜脗聯 where food packaging, plastic bags, and plastic fragments are the top three most
abundant. Due to the limitations of this study, there is a need to investigate further the different
factors on the transportation and deposition of macroplastic litters in Pulauan River that can
help to avoid threats in the aquaculture sector, for which the river is known. |