Extraction of standard sample of sediment from stream bed

摘要

Taking a sample of sediment from the bed of a stream comprises inserting a plastic tube into the stream bed and lifting by use of a builder's trowel. Taking a sample of sediment from the bed of a stream comprises marking an open-ended plastic cylinder with a strengthened metal rim at a predetermined point with a collar piece of insulating tape. The strengthened metal rim is then pushed into the bed of the stream up to the collar, and the open upper end is closed with a bung. From the downstream position, a bricklayer's trowel is pushed at an angle under the base of the cylinder, the handle being levered downwards to raise and lift the cylinder clear of the water. The cylinder and contents are then positioned over a receptacle such as a bucket, and the sedimentary contents are released and captured for later analysis.