Derwent Estuary Ambient Water Quality monitoring program - Site U7

Site U7 is sampled monthly by Nyrstar Hobart as part of the Derwent Ambient Water Quality monitoring program.
Since 2003, ambient water quality monitoring has been carried out on a monthly basis at up to 28 sites throughout the Derwent estuary by Norske Skog Boyer, Nyrstar Hobart and the State Government. Monitoring is carried out by three different boat-based sampling parties, but is co-ordinated to occur on the same day each month.
At each site, in-situ field measurements are taken using calibrated sensors for temperature, salinity, pH, dissolved oxygen and turbidity. Water clarity is also measured using a secchi disk. Surface and bottom water samples are collected for analysis of true color, total suspended solids(TSS), total and dissolved nutrients, organic carbon and zinc. at most sites, depth integrated samples are also collected for chlorophyll a using a plastic tube. Bottom samples in the Middle and Outer estuary are collected using a niskin bottle. Pumps are used in the upper estuary site to fill up the bottles. All water samples are analysed at Analytical Service Tasmania, a National Association of Testing Authorities-accredited laboratory. Monitoring site depth is 2 meters

U7监测点位由霍巴特尼尔斯塔（Nyrstar Hobart）作为德文特河（Derwent）环境水质监测计划的组成部分，每月开展采样工作。自2003年起，诺斯克·斯克格博耶厂（Norske Skog Boyer）、霍巴特尼尔斯塔（Nyrstar Hobart）与塔斯马尼亚州政府联合，在德文特河河口（Derwent estuary）沿线最多28个点位开展月度环境水质监测。该项监测由三支独立的船舶采样团队执行，但统一协调为每月同一天开展采样。在每个监测点位，使用经过校准的传感器开展原位现场测定温度、盐度、pH值、溶解氧及浊度；同时采用塞氏盘（Secchi disk）测量水体透明度。采集表层与底层水样，用于分析真色度、总悬浮颗粒物（total suspended solids, TSS）、总态与溶解态营养盐、有机碳及锌含量。多数点位还会使用塑料管采集深度整合水样以测定叶绿素a。中河口与外河口区域的底层水样采用尼斯金采水器（Niskin bottle）采集；河口上游点位则通过泵体完成采样瓶灌装。所有水样均送至塔斯马尼亚分析服务中心（Analytical Service Tasmania）检测，该机构为澳大利亚国家检测机构协会（National Association of Testing Authorities, NATA）认可的实验室。该监测点位的水深为2米。