Seawater physicochemical parameters in the green mussel belts in Samar Philippines

Abstract

Samar’s bays are among the few areas where green mussel thrives making it one of the major sources in the country. In 2007, Samar green mussel industry was almost wiped out due to mass mortality of the bivalve. Its survival depends on many variables, one of which is the environmental parameters such as salinity, dissolved oxygen, pH, temperature, chlorophyll, water current, and depth. This paper presents the characteristics of the green mussel belts including the seawater physicochemical parameters as well as a qualitative assessment of water quality from 2004 to 2013 as observed by 92 residents. Results have shown that during normal conditions, the bays the mussel belts are sandy to sandy-muddy substrates. The seabed especially near river mouths are heavily silted and have dark muddy substrates believed to be carried by river waters. During heavy precipitation, the water in the bays changes to brown color. Contaminated water flows from agricultural farms as well as fish ponds. Communities along the river and the coast of the bays dispose their domestic wastes directly into the body of water. The physicochemical parameter varies from in the three bays studied attributed to the different configuration of the bay. Average seawater temperature, salinity, DO, and pH is 26.56oC, 32.13 ppt, 7.03 ppm and 7.32 respectively. The variation is attributed to the volume of water flowing into the bays and the bay's configuration. Residents believe that seawater quality was at its worst state in the years 2007 and 2008 and have improved since then.