Effects of Tidal Events on the Water Quality in the Merbok Estuary, Kedah, Malaysia

Abstract

This study was carried out to observe effects of tidal events on the water quality parameters at Merbok estuary, Kedah, Malaysia. Twenty four hours sampling were conducted at Station 1, 2 and 3 from 12th November (spring tide) to 3rd December (neap tide) 2011 on weekly interval. Results showed that water quality parameters varied with the following ranges: temperature (26.10 - 30.7°C), pH (6.29 - 7.22), dissolved oxygen (0.65 - 5.48 mgL-1), salinity (0.50 – 35PSU), nitrate (0.037 - 0.647mgL-1), nitrite (0.09 - 0.36 mgL-1), ammonia – N (0.03 - 3.05 mgL-1), phosphate (0.03 - 0.10mgL-1). Kruskal Wallis H test showed that water quality parameters were significantly different among sampling stations (p<0.01). Mann-Whitney U test result showed that water quality parameters were significantly different between spring and neap tides (p<0.01) except temperature and nitrate. Parameters such as temperature, salinity, nitrate, ammonia – N and phosphate recorded higher in spring tide while, DO, pH and nitrite were higher in neap tide.J. Environ. Sci. & Natural Resources, 8(2): 15-19 2015