Spatially explicit estimates of length and biomass of Micromesistius poutassou (Blue Whiting) from acoustic and trawl surveys in the North-East Atlantic in May 2011

Acoustic estimates of herring and blue whiting abundance were obtained during the surveys using the Simrad ER60 scientific echosounder. The allocation of NASC-values to herring, blue whiting and other acoustic targets were based on the composition of the trawl catches and the appearance of echo recordings. To estimate the abundance, the allocated NASC -values were averaged for ICES-squares (0.5° latitude by 1° longitude). For each statistical square, the unit area density of fish (rA) in number per square nautical mile (N*nm-2) was calculated using standard equations (Foote et al., 1987; Toresen et al., 1998). To estimate the total abundance of fish, the unit area abundance for each statistical square was multiplied by the number of square nautical miles in each statistical square and then summed for all the statistical squares within defined subareas and over the total area. Biomass estimation was calculated by multiplying abundance in numbers by the average weight of the fish in each statistical square then summing all squares within defined subareas and over the total area. The Norwegian BEAM soft-ware (Totland and Godø 2001) was used to make estimates of total biomass.

Calcium carbonate content and concentration of phosphorus components in sediments of ODP Leg 171B sites

Quantifying phosphorus (P) concentrations in marine sediments is necessary for constraining the oceanic record of phosphorus burial and helps to constrain P sedimentary geochemistry. To understand P geochemistry in the sediments, we must determine the geochemical forms of P as well as the transformations occurring between these P components with depth and age. Although several records now exist of P geochemistry in the western and eastern equatorial Pacific (Filippelli and Delaney, 1995, doi:10.2973/odp.proc.sr.138.144.1995; 1996, doi:10.1016/0016-7037(96)00042-7), the western equatorial Atlantic (Delaney and Anderson, 1997, doi:10.2973/odp.proc.sr.154.124.1997), the California Current (Delaney and Anderson, in press), and the Benguela Current (Anderson et al., 2001, doi:10.1029/2000GB001270), most of these are Neogene records. Relatively little data exist from sediments of the Paleogene or Cretaceous, time periods when carbon isotope records indicate major carbon shifts and when the nature of P geochemistry has not been well constrained. Samples from several sites at various water depths, oceanographic regions, and ages are needed to understand how P geochemistry and burial in sediments reflect ocean history. We determined P geochemistry and reactive P concentrations in Atlantic sediments of Eocene to Cretaceous age. These are the first records of P geochemistry with good age control from this period. Blake Nose sites are ideal for investigating P geochemistry, as the sediments are shallowly buried at a range of water depths and sedimentation rates. We determined P concentrations and geochemistry, along with calcium carbonate contents, in mid-Cretaceous to upper Eocene sediments drilled on Blake Nose (Ocean Drilling Program Leg 171B) in a depth transect of four sites (Sites 1052, 1051, 1050, and 1049; water depths: 1345, 1983, 2300, and 2656 m, respectively).

Abundance and biomass of bacterioplankton in waters of the Kara Sea and the Ob and Yenisey Rivers

Bacterial cell number in the water column of the Kara Sea and estuary areas of the Ob and Yenisey Rivers was determined in water samples collected at 32 stations at depths from the surface to 200 m. The samples were analyzed by direct microscopy. In most parts of the sea microorganism concentrations ranged generally from 103 to 104 cells per ml and their biomasses from milligrams to tens of mg/m**3. Bacterioplankton concentration of river waters was much higher than in the open sea, especially in Ob waters. The highest bacteria concentrations, hundreds of thousands cells per ml with biomass exceeding 200 mg/m**3, were found in the southern part of the Ob section. Minimal concentrations were observed in the northeastern part and near the southeastern part of the Ob section and the southeastern coast of Novaya Zemlya. Dark CO2 fixation rates determined at some stations indicated low bacteria biomass production.

Pigment concentrations and biomass of phytoplankton and of its dominant species in surface Black Sea waters in 1998-2000

Data on chlorophyll a concentration and species composition and biomass of phytoplankton have been collected for two years continues monitoring in the central part and the slope zone of the Black Sea. Seasonal dynamics of chlorophyll a concentration correspond to U-type. It is characterized by low values in summer, high values in autumn, which are going to winter-spring bloom of phytoplankton. Oscillations of mean values of chlorophyll concentrations are equal to 3-4 in the central part and 2 - in the slope zone. In the autumn-winter-spring period high values of phytoplankton biomass are related to typical blooming diatom algae in the first year and other taxons - in the second year. Relationship between relative content of phaeopigment and chlorophyll concentration has been determined for the central western part of the sea. Seasonal dynamics of carbon/chlorophyll a ratio has been shown. For both regions mean values of this ratio were equal to ~20 in autumn-winter-spring time and 40-50 - in summer time.

Spatially explicit estimates of stock size, structure and biomass of North Atlantic albacore tuna (Thunnus alalunga) in the North Atlantic for the period 1987-2011, compiled from statistics about ICCAT fishery region L7

The development of the ecosystem approach and models for the management of ocean marine resources requires easy access to standard validated datasets of historical catch data for the main exploited species. They are used to measure the impact of biomass removal by fisheries and to evaluate the models skills, while the use of standard dataset facilitates models inter-comparison. North Atlantic albacore tuna is exploited all year round by longline and in summer and autumn by surface fisheries and fishery statistics compiled by the International Commission for the Conservation of Atlantic Tunas (ICCAT). Catch and effort with geographical coordinates at monthly spatial resolution of 1° or 5° squares were extracted for this species with a careful definition of fisheries and data screening. In total, thirteen fisheries were defined for the period 1956-2010, with fishing gears longline, troll, mid-water trawl and bait fishing. However, the spatialized catch effort data available in ICCAT database represent a fraction of the entire total catch. Length frequencies of catch were also extracted according to the definition of fisheries above for the period 1956-2010 with a quarterly temporal resolution and spatial resolutions varying from 1°x 1° to 10°x 20°. The resolution used to measure the fish also varies with size-bins of 1, 2 or 5 cm (Fork Length). The screening of data allowed detecting inconsistencies with a relatively large number of samples larger than 150 cm while all studies on the growth of albacore suggest that fish rarely grow up over 130 cm. Therefore, a threshold value of 130 cm has been arbitrarily fixed and all length frequency data above this value removed from the original data set.

Spatially explicit estimates of length and biomass of Clupea harengus (Norwegian spring spawning herring) from acoustic and trawl surveys in the North-East Atlantic in May 2004

Acoustic estimates of herring and blue whiting abundance were obtained during the surveys using the Simrad ER60 scientific echosounder. The allocation of NASC-values to herring, blue whiting and other acoustic targets were based on the composition of the trawl catches and the appearance of echo recordings. To estimate the abundance, the allocated NASC -values were averaged for ICES-squares (0.5° latitude by 1° longitude). For each statistical square, the unit area density of fish (rA) in number per square nautical mile (N*nm-2) was calculated using standard equations (Foote et al., 1987; Toresen et al., 1998). To estimate the total abundance of fish, the unit area abundance for each statistical square was multiplied by the number of square nautical miles in each statistical square and then summed for all the statistical squares within defined subareas and over the total area. Biomass estimation was calculated by multiplying abundance in numbers by the average weight of the fish in each statistical square then summing all squares within defined subareas and over the total area. The Norwegian BEAM soft-ware (Totland and Godø 2001) was used to make estimates of total biomass.

Spatially explicit estimates of length and biomass of Clupea harengus (Norwegian spring spawning herring) from acoustic and trawl surveys in the North-East Atlantic in May 2008

Acoustic estimates of herring and blue whiting abundance were obtained during the surveys using the Simrad ER60 scientific echosounder. The allocation of NASC-values to herring, blue whiting and other acoustic targets were based on the composition of the trawl catches and the appearance of echo recordings. To estimate the abundance, the allocated NASC -values were averaged for ICES-squares (0.5° latitude by 1° longitude). For each statistical square, the unit area density of fish (rA) in number per square nautical mile (N*nm-2) was calculated using standard equations (Foote et al., 1987; Toresen et al., 1998). To estimate the total abundance of fish, the unit area abundance for each statistical square was multiplied by the number of square nautical miles in each statistical square and then summed for all the statistical squares within defined subareas and over the total area. Biomass estimation was calculated by multiplying abundance in numbers by the average weight of the fish in each statistical square then summing all squares within defined subareas and over the total area. The Norwegian BEAM soft-ware (Totland and Godø 2001) was used to make estimates of total biomass.

Spatially explicit estimates of length and biomass of Clupea harengus (Norwegian spring spawning herring) from acoustic and trawl surveys in the North-East Atlantic in May 2009

Acoustic estimates of herring and blue whiting abundance were obtained during the surveys using the Simrad ER60 scientific echosounder. The allocation of NASC-values to herring, blue whiting and other acoustic targets were based on the composition of the trawl catches and the appearance of echo recordings. To estimate the abundance, the allocated NASC -values were averaged for ICES-squares (0.5° latitude by 1° longitude). For each statistical square, the unit area density of fish (rA) in number per square nautical mile (N*nm-2) was calculated using standard equations (Foote et al., 1987; Toresen et al., 1998). To estimate the total abundance of fish, the unit area abundance for each statistical square was multiplied by the number of square nautical miles in each statistical square and then summed for all the statistical squares within defined subareas and over the total area. Biomass estimation was calculated by multiplying abundance in numbers by the average weight of the fish in each statistical square then summing all squares within defined subareas and over the total area. The Norwegian BEAM soft-ware (Totland and Godø 2001) was used to make estimates of total biomass.

Abundance and biomass of zooplankton collected in 1995 and 1998 in the frontal zone between the Gulf Stream and the Labrador current

Vertical distribution of meso- and macroplankton was studied in the region of the most sharply pronounced climatic frontal zone between the Gulf Stream and the Labrador current. Hauls with a plankton net BR 113/140 and visual counts of macroplankton from the Mir submersible were used. In the frontal zone a contact occurs between arctic-boreal communities and communities of the North Atlantic subtropical gyre. The community of the North Atlantic subtropical gyre is more mature in terms of succession; many macroplanktonic carnivores-scavengers (mainly shrimps Acanthephyra) develop there and form a ''living network'' feeding on those transported from the north rich arctic-boreal mesoplankton. As a result biomass of shrimps appears to be significantly higher than biomass of their preys. Peculiarities of vertical distribution and population structure of shrimps were analyzed. Data on quantitative vertical distribution of total biomass of meso- and macroplankton and its principal groups, including gelatinous animals (ctenophores, medusas, and siphonophores) were obtained. Variations of the role of different plankton groups with depth were considered; these data enable a conclusion that frontal variations of the community structure embrace the depth range from the surface down to 2000 m.