교육데이터 활용•지원 서비스

This dataset summarises the results of a survey to determine the concentration of trace metals from mine-derived pollution in marine waters and sediments across the Torres Strait during October 2016. Sampling was performed by a CSIRO team between 3 and 16 October 2016 on board the MV Eclipse. Surface water samples were collected from 21 sites using strict sampling protocols that are designed to minimise contamination (USEPA, 1996; Angel et al., 2010b). METHODS: Sample Collection Clean powder-free vinyl gloves were worn for the handling of all sample bottles and sampling equipment, and the collection of water samples before sediment samples at any given site. Acid washed sampling bottles (0.5, 1, and 5 L), double-bagged in zip-lock bags and stored inside an esky containing ice bricks was transported on the tender to each site. The 0.5 L bottle was used to collect a sample for total mercury analysis. The 1 L bottle was used for collecting a sample for total recoverable metals analyses other than mercury, and the 5 L bottle was used for collecting a sample for filterable (dissolved) and TSS-bound metals analyses other than mercury. At every sampling site a ‘clean hands’, ‘dirty hands’ protocol was used for taking water samples. This involved the ‘clean hands’ person opening the esky, placing gloves on hands, withdrawing the 1 L sample bottle from pre-labelled zip-lock bags, placing it into an attachment on a purpose built Perspex pole sampler, uncapping the bottle and holding onto the cap. The ‘dirty hands’ person then rapidly submerged the bottle in the pole sampler to a depth of approximately 50 cm to take the sample. Each sample bottle was rinsed twice with water from the sample site by filling each bottle, capping, shaking and emptying. The 1 L bottle was used to collect water samples that were decanted into the 0.5 and 5 L bottles until they were full of sample, after which the 1 L bottle was filled a final time. The ‘clean hands’ person capped each bottle once they well filled and replaced them into the zip-lock bags in the esky. The water samples were placed into a fridge on board the MV Eclipse prior to filtration. The samples were filtered within 6 hours of sample collection. For quality control purposes, field blanks were collected at sites M, O and 8 and duplicate samples were collected at sites N, O and A. Field blanks for trace metals analysis were prepared at the designated sites by opening a 1 L bottle to the air for approximately 30 seconds followed by capping and returning to its zip-lock bag. On return to the MV Eclipse, the bottle was then filled with 1 L of deionised water. Salinity and pH were measured using an Orion Star A329 portable meter (Thermo Scientific). Sample pH was measured using a Thermo Scientific Orion Gel-Filled ROSS pH Ultra Triode Electrode (8107UWMMD) that was calibrated using pH 4.00, 7.00 and 10.00 buffers. Salinity was measured using a Thermo Scientific Orion Conductivity Cell (013010MD) that was calibrated using KCl conductivity standards. Sediment samples were collected from each site immediately after the water sampling. A combination of techniques were employed to collect the sediment samples that depended on the local water current conditions and ability of the corer to penetrate the sediment. Firstly, a gravity core sampler was deployed from the Eclipse, which collected up to 12 cm deep sediment within pre-loaded plastic core tubes. If this was unsuccessful divers took hand cores of up to 7 cm depth by diving to the sea bed. The core tubes were capped with plastic stoppers and wherever possible, returned to the surface in an upright position. If the substrate was too hard for hand coring, the divers took a grab of loose sediment samples by hand inside 250 mL polycarbonate vials. The core tubes were withdrawn from the corer on-board the MV Eclipse, placed into zip-lock bags, and placed inside a freezer until frozen. The cores were then sectioned by allowing a core to partially thaw