Organic Matter Load in Pangean Reservoir Pangean District, Kuantan Singingi Regency, Riau Province

Abstract

Abstract

Pangean reservoir is one of the reservoirs in Pangean district which has a primary function as a irrigation, PDAM and has been used for floating cage fish culture activities. Increasing fisheries activities will increase organic matter that enter the water and and as a consequence it affect water quality in general. A study aims to understand the organic matter load in Pangean Reservoir has been conducted in July-August 2019. Samples were taken from four station, once/week for a weeks. In each station there were 3 sampling point surface, 2 Secchi depth and 4 Secchi depth. Determination of daying coefficient was based on the BOD timeseries (2,4,6,8,10 day). Water quality parameter measured were temperature, transparency, depth, pH, dissolved oxygen, and BOD₅. Result shown that decaying coefficient was 0,24-0,124 k/day, temperature was 29-31^oC, transparency was 92-102 cm, depth was 248-388 cm, pH was 4-5, dissolved oxygen was 5-6,2 mg/L and BOD₅ was 9,6-22,4 mg/L. The decaying coefficient and BOD intertime value indicate that the organic matter in the Pangean reservoir represent as load (P<B) in the water, as the decaying rate is slower than the input rate of organic matter.

Keywords : BOD timeseries, decaying coefficient, dissolved oxygen, water quality