Investigation of the Heavy Metals Contaminations in Water ,and Sediment in the A-Gong-Dian River

• Main Authors: Li, Hao-Ying, 李皓瀅
• Other Authors: Lin, Chitsan
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/54359916312674600020

碩士 === 國立高雄海洋科技大學 === 海洋環境工程研究所 === 103 === The Agongdian River is an important river in northern Kaohsiung, which is a residential- and industrial-intensive area. Many polluting substances have been injected into the Agongdian River, doing great harm to the aquatic ecosystem of the Agongdian River and endangering human health. This study mainly collected the on-site samples to supervise and analyze the sediment and water of the Agongdian River and to understand the distribution of heavy metal concentration of the sediment and water, enrich factors, the cumulative extent and the potential influence on the aquatic ecosystem of the Agongdian River. There are a total of 10 sampling points located from the upstream to downstream along the Agongdian River. (including Catchments, Sheng Nan Gong, Sheng San Bridge, Daren Bridge, Agongdian Bridge, Xian Bridge, the left side of Qiangzhou Bridge, the right side of Qiangzhou Bridge, Weiren Bridge and the Old Port Bridge）The sampling periods are November in 2012, February and April in 2013, as well as September in 2014. The analytical subjects are eight heavy metals. The analytical results show that concentration of metals in surface water that exceeds the standards for surface water quality. These trace metals are arsenic (exceeding the rate of 3.7%), copper (exceeding the rate of 18.5 %), mercury exceeding the rate of 7.4%) and zinc (exceeding the rate of 44.8%). Since the standards for surface water quality have no limitation on nickel, concentration of nickel does not exceed the rate compared with underground water quality with sewage treatment. The average concentration of metals exceeds the upper limit for the sediment quality indicator of category management and use restrictions. These trace metals are mercury (exceeding the rate of 29.6%) and zinc (exceeding the rate of 77.8%), among which the maximum value of the zinc is higher than 48 times of the upper limit. The total enrich factor (EF) of mercury is 0.07 ~ 46.64, the total enrich factor of zinc is 3.59 ~ 23.51, the total enrich factor of arsenic is 3.52 ~ 8.54, and the total enrich factor of lead is 2.38 ~ 9.85. The reason for the enrichment mainly lies in the manmade pollution with a heavy amount of zinc and mercury. As the Sediment Quality Guidelines (SQGs) show, zinc and mercury cumulated in the Agondian River are with higher potential toxicity. The potential toxicity probability is up to 74％. Meanwhile, the results analyzed by the geo-accumulation index (Igeo）also point out a serious zinc accumulation in bed sediments（Igeo = 4.9）, a medium mercury accumulation（Igeo = 1.7）, non- to medium accumulation of cadmium and lead （Igeo = 0.0-0.7）, and non-accumulation of arsenic, chromium, copper and nickel（Igeo＜1）. On the other hand, the potential ecological risk index (PERI） shows that the heavy metals in bed sediments of the Agongdian River belong to a high level of potential ecological risk. Mercury is the major metal that results in this risk. The total sum of the risk indicators for individual metals（RI = 269）indicates that the heavy metals in the Agondian River will bring medium potential risk to the aquatic ecosystem of the Agondian River.