Secchi disk definition

Secchi disk means a tool that is used to measure the transparency of lake water. A Secchi disk is an eight-inch weighted disk on a calibrated rope, either white or with quadrants of black and white. To measure water transparency with a Secchi disk, the disk is viewed from the shaded side of a boat. The depth of the water at the point where the disk reappears upon raising it after it has been lowered beyond visibility is recorded.
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Secchi disk means a device for measuring water clarity that consists of a circular weighted disk painted in flat black and white in alternating quarters that is suspended on an incremented rope or line.
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Secchi disk means a 30 cm diameter circular disk used to measure the transparency of water by being lowered into the water column until no longer visible;
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Examples of Secchi disk in a sentence

  • The clarity of the water is such that a Secchi disk is visible at the bottom of the tank.

  • Field measurements include water depth, water temperature, and Secchi disk transparency.

  • An algal bloom is defined as a planktonic growth of algae which causes Secchi disk transparency to be less than 2.0 meters.

  • The affected water has a recent history of severe algae blooms of less than one meter Secchi disk transparency;[PL 1995, c.

  • Application of an algicide may only occur after the Secchi disk transparency of the water is less than 2 meters.

  • Three parameters are the most important measures of eutrophication in most New York lakes: total phosphorus, chlorophyll a (estimating the amount of algae), and Secchi disk transparency.

  • Wherever the water is less than 10 feet deep, the Secchi disk reading shall not be less than 80 percent of the depth in more than 20 percent of the readings in any zone.

  • While depth of the zone varies with many factors, it can be estimated as a multiple of the Secchi disk transparency (SDT).

  • Secchi disk readings have improved from less than 10 feet before the project to up to 20 feet during July 2004 after the alum treatment.

  • It also affects the length of the recreational season Secchi Disk Transparency (m) Conductivity (µmho/cm) pH Color (true) (platinum color units) Phosphorus (total, mg/l) Nitrogen (nitrate, ammonia, and total (dissolved), mg/l) Chlorophyll a (µg/l) Calcium (mg/l)Determined by measuring the depth at which a black and white disk disappears from sight, the Secchi disk transparency estimates the clarity of the water.


More Definitions of Secchi disk

Secchi disk means a 200 mm. circular plate which has opposite quarters painted gloss white and black.
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Secchi disk means a 200-mm ( 7 7/8 inches) circular plate which has opposite quarters of the same face painted gloss white and black.
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