Bio-optical characteristics of coastal waters: Absorption spectra of phytoplankton and pigment distribution in the western North Atlantic

Monthly temperature-salinity diagrams for 1957 have demonstrated that three surface oceanic "water bodies" were consistently present in the eastern North Atlantic; two are regarded as modified North Atlantic Central water which give rise to the third by mixing. As well in the oceanic areas, large and small, high or low salinity patches of water were common. Effects of seasonal climatic fluctuations differed in the several oceanic water bodies. In coastal waters, differences in properties and in seasonal and annual cycles of the properties distinguish the waters from the North Sea, English Channel and the western entrance to the Channel.The geographic distributions of the oceanic waters are consistent with "northern" and "southern" water bodies mixing to form a "transitional" water. Within this distribution there are short-term changes in boundaries and long-term (seasonal) changes in size of the water bodies.Water in the western approaches to the English Channel appeared to be influenced chiefly by the mixed, oceanic transitional water; oceanic influences in the North Sea appear to have been from northern and transitional waters.

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Optical characteristics of colored dissolved organic matter during blooms of Trichodesmium in the coastal waters off Goa

Environmental Monitoring and Assessment ◽

10.1007/s10661-020-08494-w ◽

2020 ◽

Vol 192 (8) ◽

Author(s):

Albertina Dias ◽

Siby Kurian ◽

Suresh Thayapurath

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Coastal Waters ◽

Optical Characteristics ◽

Colored Dissolved Organic Matter

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Artificial light in baited pots substantially increases the catch of cod (Gadus morhua) by attracting active bait, krill (Thysanoessa inermis)

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy099 ◽

2018 ◽

Vol 75 (6) ◽

pp. 2257-2264 ◽

Cited By ~ 8

Author(s):

Odd-Børre Humborstad ◽

Anne Christine Utne-Palm ◽

Michael Breen ◽

Svein Løkkeborg

Keyword(s):

Light Source ◽

North Atlantic ◽

Coastal Waters ◽

Gadus Morhua ◽

Catch Rate ◽

Light Sources ◽

The North ◽

Important Prey ◽

Large Numbers ◽

Per Se

Abstract The use of pots in the north Atlantic finfish fisheries is negligible because this fishing method typically has a low capture efficiency. Large numbers of individuals encounter baited pots, but the proportions of fish that enter the pot and become caught are low. Krill, which constitutes an important prey for cod (Gadus morhua), is attracted by light. The catching efficiency of baited cod pots with three light sources with different colours and intensities (white: 9744 mW m−2, white: 23 mW m−2, green: 8 mW m−2) were tested in coastal waters in northern Norway. Pots with the light source of highest intensity gave a 17 times higher catch rate of cod than that of control pots (with bait only). The light source of medium intensity gave about a five times higher catch rate, whereas the weakest light did not influence the catch. Cod caught in pots with light had more krill and arrowworms in their stomach and were observed feeding on these preys inside the pot. We concluded that light sources of increasing intensity attract more krill, and that cod were attracted into the pot by the dense swarms of prey and not the light per se.

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Northern Range Extension of the Atlantic Mackerel, Scomber scombrus, to Black Island, Labrador

Journal of the Fisheries Research Board of Canada ◽

10.1139/f70-066 ◽

1970 ◽

Vol 27 (3) ◽

pp. 610-613 ◽

Cited By ~ 2

Author(s):

L. S. Parsons

Keyword(s):

North Atlantic ◽

Coastal Waters ◽

Range Extension ◽

Range Limit ◽

Atlantic Mackerel ◽

Scomber Scombrus ◽

Northern Range Limit

During August 1969, 785 specimens of Scomber scombrus were captured in southern Labrador coastal waters, extending the known range in the western North Atlantic to Black Island, Labrador, more than 50 miles north of Triangle Harbour, the previously authenticated northern range limit.

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Optical characteristics of coastal waters and atmosphere near the south coast of the crimea at the end of summer 2008

Physical Oceanography ◽

10.1007/s11110-010-9079-x ◽

2010 ◽

Vol 20 (3) ◽

pp. 207-230

Author(s):

V. I. Man’kovskii ◽

G. A. Tolkachenko ◽

E. B. Shibanov ◽

O. V. Martynov ◽

E. N. Korchemkina ◽

...

Keyword(s):

Coastal Waters ◽

South Coast ◽

Optical Characteristics ◽

The South ◽

The Crimea

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The harbour porpoise (Phocoena phocoena) in the North Atlantic: Variability in habitat use, trophic ecology and contaminant exposure

NAMMCO Scientific Publications ◽

10.7557/3.2749 ◽

2003 ◽

Vol 5 ◽

pp. 223 ◽

Cited By ~ 1

Author(s):

Arne Bjørge

Keyword(s):

Habitat Use ◽

North Atlantic ◽

Coastal Waters ◽

Trophic Ecology ◽

Point Sources ◽

Phocoena Phocoena ◽

Cetacean Species ◽

Contaminant Exposure ◽

The North ◽

Management Plans

Harbour porpoises inhabit coastal waters, in habitats that are characterized by high diversity and complexity in terms of their bathymetry, substrate, fish communities and point sources of contaminants. The complexity in these habitats influences both the habitat use and feeding ecology of porpoises. Congregations of porpoises feeding primarily on one species are observed in some areas and seasons, while wide movements and diets composed of several species are observed in other areas. Due to these observations, this paper suggests that caution is needed when extrapolatingknowledge from one area to another with regard to porpoise habitat use, exposure to contaminants, and interactions with fisheries. Management plans should be site specific and based on local knowledge incorporating porpoise population structure, habitat use, and multiple environmental factors in order to ensure appropriate conservation of this abundant but still vulnerable small cetacean species.

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Inversion of the volume scattering function and spectral absorption in coastal waters with biogeochemical implications

Biogeosciences Discussions ◽

10.5194/bgd-10-9003-2013 ◽

2013 ◽

Vol 10 (6) ◽

pp. 9003-9041

Author(s):

X. Zhang ◽

Y. Huot ◽

D. J. Gray ◽

A. Weidemann ◽

W. J. Rhea

Keyword(s):

Absorption Spectra ◽

Coastal Waters ◽

Chlorophyll Concentration ◽

Hplc Method ◽

Scattering Coefficient ◽

Spectral Absorption ◽

Volume Scattering ◽

Total Scattering ◽

Inherent Optical Properties ◽

Complete Set

Abstract. In the aquatic environment, particles can be broadly separated into phytoplankton (PHY), non-algal particle (NAP) and dissolved (or very small particle, VSP) fractions. Typically, absorption spectra are inverted to quantify these fractions, but volume scattering functions (VSFs) can also be used. Both absorption spectra and VSFs were used to calculate particle fractions for an experiment in Chesapeake Bay. A complete set of water inherent optical properties was measured using a suite of commercial instruments and a prototype Multispectral Volume Scattering Meter (MVSM); the chlorophyll concentration, [Chl] was determined using the HPLC method. The total scattering coefficient (measured by an ac-s) and the VSF (at a few backward angles, measured by a HydroScat 6 and an ECO-VSF) agreed with the LISST and MVSM data within 5%, thus indicating inter-instrument consistency. The size distribution and scattering parameters for PHY, NAP and VSP were inverted from measured VSFs. For the absorption inversion, the "dissolved" absorption spectra were measured for filtrate passing through a 0.2 μm filter, whereas [Chl] and NAP absorption spectra were inverted from the particulate fraction. Even though the total scattering coefficient showed no correlation with [Chl], estimates of [Chl] from the VSF-inversion agreed well with the HPLC measurements (r = 0.68, mean relative error s = −20%). The scattering associated with NAP and VSP both correlated well with the NAP and "dissolved" absorption coefficients, respectively. While NAP dominated forward, and hence total, scattering, our results also suggest that the scattering by VSP was far from negligible and dominated backscattering.

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