Fishes and zooplankton were obtained (March-April 1979 and partly in August 1974) from 45 hauls taken during the day and at night in the central equatorial Atlantic between Latitude 3 ~ and 2 ~ from the surface to 1 250-m depth, using the RMT 1+8, a combined opening-closing plankton and micronekton trawl. The vertical distribution of 30 myctophid species is described.All species migrate in a diel pattern, Ceratoscopelus warmingii and Lampanyctus photonotus down to at least 1 250 m. During daytime most species aggregated at 400-to 700-m depth, therefore only partly occupying the depth of the Deep Scattering Layer (400 to 500 m at 15 kHz). The feeding patterns of seven of the most abundant species were compared, with a total of 1 905 stomach contents being analysed. All seven species are regarded as opportunistic predators, which feed predominantly during the night on calanoid copepods. A total of 66 species of calanoid copepods were identified among the prey items, with smaller species definitely being in the minority.Stomachs of C. warmingii (700 to 1 250 m depth) and Lepidophanes guentheri (500 to 900 m depth) from daytime samples contained copepod species restricted to the upper 150 m of the water column, including Undinula vulgaris, Nannocalanus minor, and Euchaeta marina, thereby confirming an extended vertical migration of predators. Differences in diet and preferences between species in their total food spectrum are described.
Five apple juices were produced on a pilot scale by crushing the fruit, treating the mash with pectolytic enzymes, pressing, extracting water from the pomace, pasteurization, treatment of the juice with enzymes, combined gelatin/silica sol fining and final ultrafiltration. The temperature of the mash treatment was either ambient or one of 30, 40, 50 or 60°C, in order to test whether this led to different compositional changes in the corresponding juices. The main emphasis was put on detection of D-galacturonic acid as the indicator substance for the extent of the enzymatic treatment. In the pasteurized raw juices after pressing we found values from 226 to 398 mg L )1 . A distinct increase of the galacturonic acid levels could be observed during the clarification steps. Enzymatic juice treatment raised the concentrations to 580-720 mg L )1 . After ultrafiltration, final values of 790-1100 mg L )1 were measured. Generally, the highest values were found in the 50°C sample, which is the optimum temperature for pectinase activity. This was also true for the colloid concentrations and polyphenols. The influence of the temperature of the enzymatic mash treatment on other characteristic juice parameters like total titratable acidity, density, sugar, and minerals concentrations was low.
The copepod fauna southwest of the British Isles includes a number of species which have their centre of distribution in the subtropical or tropical Atlantic. Among these, some species appear to be faunistically linked with the Iberian continental slope or slope waters even farther south along the NE Atlantic margin. It seems that these species reach their northeastern range by means of poleward-flowing currents. For example, CaEanoides carinatus has deep-living resting stages and ascends to surface waters only during its reproductive period, which is short at northern latitudes. Its main dwelling layers along the west Iberian continental slope cover the poleward-flowing undercurrent and the Mediterranean outflow water underneath. Part of the poleward flow regime tends to follow the slope bathymetry, i.e. it bends eastwards into the Bay of Biscay along northern Spain. Another part separates from the continental slope at Cape Finisterre and crosses the Bay of Eiiscay, approaching the continental slope at about 47" N, where it joins the north-westward flowing slope currents again. Because of its preference for the deeper layers during the long resting phase it is assumed that resting C. carinatus drifts mainly with the northward branch of the Mediterranean outflow water and penetrates only slightly into the inner Bay of Biscay. In contrast, Calanus helgolandicus has, on average, a shallower vertical distribution. Reproductively active individuals occur in the surface layers off western Iberia throughout the year. Here it drifts presumably northwards during late autumn and winter, but is recirculated southwards during late spring and summer. Due to advection with both the intermediatl-undercurrent and the variable near-surface currents, Calanus helgolandicus occurs more commonly in the inner IBay of Biscay than C. carinatus. 0 Elsevier, Paris Bay of Biscay I continental slope current I Mediterranean water I salinity minimum I copepod transport RCsumC-Transport de copCpodes par la circulation le long de la pente continentale du golfe de Gascogne. Au sudouest des iles Britanniques, la faune de copCpodes comprend de nombreuses espbces originaires de 1'Atlantique tropical ou subtropical. Certaines, likes B la faune de la pente continentale ibQique ou, plus au sud, B celle de la marge nord-est de l'titlantique, arriveraient avec les courants dirigCs vers le p81e. Ainsi, Calanoides carinatus se trouve en profondeur pendant ses pCriodes de repos et ne remonte dans les eaux de surface que pendant la ptriode de reproduction, b&e aux latitudes nord. Plongeant le long de la pente continentale & l'ouest de la pCninsule ibCrique, il atteint le sous-courant dirigC vers le p6le et les eaux sous-jacentes issues de la mer MtditerranCe. Une partie du flux suit la bathymktrie en direction de l'est et entre dans le golfe de Gascogne au nord de 1'Espagne. Une autre partie du flux quitte le talus continental au cap Finisterre et traverse le golfe de Gascogne pour retrouver, vers 47" N, la pente continentale et les courants orient& vers le
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