Author(s): Yusuke Horiuchi; Takuya Matsuura; Taichi Tebakari; Sanit Wongsa
Linked Author(s):
Keywords: Mate-analysis; Water quality; Chao Phraya River; Thailand
Abstract: Since August 2016, we have carried out more than two years of on-site observations and water quality analyses in the lower reaches of the Chao Phraya River in Thailand. The water quality characteristics were assessed based on automatically collected water quality and water level data, obtained from the Thai government. In addition to these results, we investigated changes in water quality by comparing our results to those of previously reported field observations and water quality analyses. According to our results, water quality characteristics vary significantly with the season due to changes in natural discharge in the rainy season and constant discharge by the Chao Phraya Dam during the dry season. In the dry season, the salinity intrusion range was larger, with high salinity, and the water had low temperatures and oxygen contents. During the rainy season, the salinity intrusion range was suppressed, and the water had low salinity, high temperature, and high oxygen contents. The longitudinal river pH was alkaline. Previously, the salinity of the water was high from the mouth of the river to a distance of 100 km downstream, and had a high oxygen content at distances from 150 to 350 km from the river mouth and low oxygen near the river mouth. The pH of the water was alkaline longitudinally along the river, with the value decreasing from upstream to downstream. There were no significant differences between the water quality characteristics detected in this study and those reported previously.
Year: 2020