Sediment Movements in Estuary of Siak River, Riau Basin, Indonesia

Abstract

Siak river has a long history as a transportation lane in the east of Sumatera. From traditional to timber transportations are dependent on this river. Now the river is a severe suffering pollutant spill from many sources. Anthropological activities were higher contributions in the degradation of river environments. Many works were reported about pollution in Siak river. But how the distribution of model sediment transport in the mouth of the river is less to be explained. We consider hydrodynamics model of the mouth of Siak river for modeling the sediment distribution. This simulation gives a fundamental and clear understanding of how total solid sediment (TSS) distribution when flood and ebb tide happens. At ebb tide, TSS dispersion is higher than at flood tide. There is found that the sediment is concentrated in the plume of Siak river in Bengkalis strait. The composition of the sediment is dominated by organic matters.

Physical and chemical characteristics of Socah Estuary, Bangkalan

“…This value indicates that the Socah estuary waters fall into the class 1 category where the TSS value is less than 1000 mg/L based on the estuary river quality standard [10]. TSS affects the photosynthesis process in the waters, where if the TSS is high, it affects the water column so that photosynthesis, DO, and CO2 depend on TSS in the waters [1], [6], [10].…”

“…When the salinity measurement at several stations is carried out when the seawater is heading towards high tide, the salinity level in the estuary increases. Salinity in the estuary is influenced by tidal conditions, rain, and the entry of waste from settlements, agriculture, and aquaculture activities [10], [11]. The pH range in the Socah estuary ranges from 6.8 -7.5, indicating that the pH is alkaline because sea tides influence the salinity of the Socah estuary at the time of measurement.…”