Secchi disk observations in Dartmouth"s lakes, 1977

by Donald C. Gordon

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Published 1978 by Bedford Institute of Oceanography in Dartmouth, N.S .
Written in English

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Edition Notes

Microfiche. Ottawa : Public Archives, Canada, 1978. 1 microfiche : negative ; 11 x 15 cm.

Statement	by Donald C. Gordon, Jr.
Series	Report series / Bedford Institute of Oceanography ;, BI-R-78-2
Classifications
LC Classifications	Microfiche 86/205 (Q)
The Physical Object
Format	Microform
Pagination	iii, 15 p.
Number of Pages	15
ID Numbers
Open Library	OL2358370M
LC Control Number	86893505

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The disappearance depth in metres is noted as Secchi disk depth. A Forel-Ule observation is done over the Secchi disk at ½ its depth. The observer compares the colour of the water column over the disk with one of the scale colours. One of the first maps with Forel-Ule sea colour observations appeared in scientific literature in (Figure 3). 6. SECCHI DISK TRANSPARENCY A measurement of water transparency obtained by observing a specially marked, circular disk which is lowered through the water column until it is not visible. This measure of the point at which the disk is non-visible is considered the secchi depth. Secchi disk use (Figure 11) Conditions for secchi disk File Size: 16MB.

The best-known operational estimation of water transparency is the Secchi disk, created by Pietro Angelo Secchi SJ in , and is a circular disk used for clarity measurements in oceans and lakes. The disc mounts on a line and lowers slowly down in the water until the pattern on the disk is no longer visible. This measure is known as the Cited by: Canavan, Richard W. IV and Siver, Peter A. Connecticut Lakes: A Study of the Chemical and Physical Properties of Fifty-six Connecticut Lakes. Pp Published by the Connecticut College Arboretum, Box Conn. College, Mohegan Ave., New London, CT . predictive tool to monitor the biological conditions (algal biomass or nutrient concentration) of lakes and inland waters (Carlson ). The water transparency parameter and prediction of diver’s visibility have major implications in port and harbor security and are quite instrumental to recreational and commercial diving industries (Trees.

The Secchi disk (or Secchi disc), as created in by Angelo Secchi, is a plain white, circular disk 30 cm (12 in) in diameter used to measure water transparency or turbidity in bodies of water. The disc is mounted on a pole or line, and lowered slowly down in the water. The depth at which the disk is no longer visible is taken as a measure of the transparency of the water.   It is recommended that one first determine the SDD and then raise the Secchi-disk to half that value. Whilst it is at half SDD, the best matching colour of the water mass is identified by looking at the colour tubes or strips of the handheld FUI colour scale over the water mass surface immediately over the submerged Secchi-disk [ 32 ].Cited by: In Fig. , typical Nomarski differential interference contrast micrographs are presented. Phosphorus concentration (PH 3 /CH 4) is ppm during the diamond growth and the film thickness is 1 μm for (A) and 5 μm for (B), respectively.A thinner layer shows rather flat surface morphology as shown in Fig. particles observed in the image are contaminants adsorbed accidentally.