Comparison of flavor components in shrimpLitopenaeus vannameicultured in sea water and low salinity water

Absolute Growth, hemolymp osmolality, oxygen consumption, and basal energy of Litopenaeus vannamei postlarvae were investigated. After post larval stage, PL-20, the postlarvae were acclimatized from sea water (25 ppt) to low salinity water (2 ppt) over 96 h. Treatments consisted of different concentration of K+added to distilled water. Four different levels of K+ (0, 30, 60, and 90 ppm) were utilized. Ten shrimp were placed in triplicate 40-L glasses aquarium. Results from the 42-day K+ growth trial indicated significant differences (P< 0.05) in absolute growth, hemolymp osmolality, oxygen comsumption, and basal energy. The values in treatment A was significantly higher than than those under the other four treatments. The results suggest treatment C were the optimum K+ level for culture vaname postlarvae in low salinity water. Keywords : Litopenaeus vannamei, oxygen comsumption, hemolymp

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Water budgets in accretionary wedges: a comparison

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1991.0138 ◽

1991 ◽

Vol 335 (1638) ◽

pp. 315-330 ◽

Cited By ~ 32

Keyword(s):

Steady State ◽

Subduction Zones ◽

Large Scale ◽

Sea Water ◽

Sedimentary Basins ◽

Surface Flow ◽

Long Distance ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water

Direct or indirect measurements of fluid flow out of the toe of accretionary wedges have now been made in the Barbados, Central Oregon, Northern Cascadia and Nankai subduction zones. The steady-state local compaction model predicts velocities of fractions of a millimetre per year and total outflows from the toe of a few cubic metres per year per metre of length along strike of the subduction zone (m2 a-1). Sea bottom measurements reveal channellized flows at velocities of hundreds of metres per year and total outflows from the toes of a few hundreds of square metres per year. Thermal arguments show in the Nankai area that all of this large surface flow cannot come from as deep as the decollement and that consequently a significant dilution by shallow sea water convection must be present. We propose that this convection is driven by the reduced density of less saline fluid of deep origin. Thus the outflow of water of deep origin may be only a few tens of square metres per year. We note, however, that there are indications in the Barbados area of massive flow of low salinity water at depth along the decollement. These flows imply the existence of large scale non-steady-state lateral transport and require the existence of sources of low salinity water. These might include the smectite-illite transformation and the fluid contained in the oceanic crust. However, these sources are limited and the possibility exist that other more important sources may be required such as long distance transport of fresh water from adjacent sedimentary basins and (or) recharge mechanisms such as the seismic pumping one.

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Short term summer to autumn variability of dissolved lipid classes in the Ligurian sea (NW Mediterranean)

Biogeosciences ◽

10.5194/bg-6-1229-2009 ◽

2009 ◽

Vol 6 (7) ◽

pp. 1229-1246 ◽

Cited By ~ 19

Author(s):

M. Goutx ◽

C. Guigue ◽

J. F. Ghiglione ◽

M. Pujo-Pay ◽

V. Raybaud ◽

...

Keyword(s):

Surface Layer ◽

Water Column ◽

Sea Water ◽

Transitional Period ◽

Ligurian Sea ◽

Low Salinity ◽

Low Salinity Water ◽

Nw Mediterranean ◽

Salinity Water ◽

Matter Transfer

Abstract. Changes in concentration and composition of Iatroscan-measured dissolved lipids were examined at a daily to month scale, in relation to the hydrological and biological context at a central site of the Ligurian sea, NW Mediterranean during the PECHE-DYNAPROC 2 experiment (14 September to 17 October 2004). Lipid concentrations (excluding hydrocarbons) (TLd-HC) and TLd-HC to DOC ratios in the 0–1000 m water column, varied from 5.3 to 48.5 μg l−1 and 0.01 to 0.09, respectively. The highest TLd-HC concentration values were found in the 0–50 m surface layer, coinciding with phytoplankton biomass. Significant correlations (p<0.01, n=87) between glycolipids from chloroplast membranes, namely the monogalactosyldiacylglycerols, a major component of dissolved lipids (25.1±10.8% of TLd-HC, n=166), and various phytoplankton pigments (chlorophyll cs-170, violaxanthin, diadinoxanthin, zeaxanthin, and lutein), suggested that picoeucaryote phytoplankton were a major source of dissolved lipids. Lipid metabolites (free fatty acids, alcohols, diacylglycerols and monoacylglycerols), an other important component of TLd-HC (37.6±11.1%, n=166), showed a greater degree of degradation of lipids in this transitional period than previously observed earlier in the year. Zooplankton wax and steryl ester biomarkers (WSE) and triacylglycerols showed a distinct periodicity in the mesopelagic layer throughout the period investigated. Concentrations of WSE (5.5–13.6 μg/l) increased in the 0–150 m surface layer, mid-way through the cruise (4–6 October), before the winter mixing. WSE were observed later and deeper in the mesopelagic layer (6–11 October), accompanied by rebounds in hydrocarbons (6–8 October) and phospholipid concentrations (12 October) in the 400–1000 m depth layer. Zooplankton migration and/or fecal pellet egestion, followed by DOM release from POM, were likely responsible for the appearance of these lipid signatures in the mesopelagic layer. Because we observed these signatures during low wind period only (<15 knots: 28 September–12 October), it may indicate that this organic matter transfer to depth was related to undisturbed trophic web in the water column above. The low salinity water lenses that appeared twice during the cruise in the 40–80 m surface layer had little effect on dissolved lipid concentrations. Lower concentrations in phosphoglycerides and hydrocarbons (HC) than in nearby sea water suggested different microbial assemblages and different level of HC contamination in this low salinity water.

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