ALBERT

Description: ... Overall, An Introduction to Programming with Mathematica is a useful and readable book that could serve as the text for a generic programming class, a supporting text for a class on programming for geoscientists, or an introduction for experienced geoscience programmers looking for an easily readable summary of Mathematica's programming language. Experienced Mathematica programmers may find it useful as a refresher. The book's principal drawbacks are the high price of Mathematica for those who do not already have the software (although a modestly priced student version is available) and, for geoscientists in particular, a lack of relevant example problems

Description: Fundamentals of Structural Geology provides a new framework for the investigation of geological structures by integrating field mapping and mechanical analysis. Assuming a basic knowledge of physical geology, introductory calculus and physics, it emphasizes the observational data, modern mapping technology, principles of continuum mechanics, and the mathematical and computational skills, necessary to quantitatively map, describe, model, and explain deformation in Earth's lithosphere. By starting from the fundamental conservation laws of mass and momentum, the constitutive laws of material behavior, and the kinematic relationships for strain and rate of deformation, the authors demonstrate the relevance of solid and fluid mechanics to structural geology. This book offers a modern quantitative approach to structural geology for advanced students and researchers in structural geology and tectonics. It is supported by a website hosting images from the book, additional colour images, student exercises and MATLAB scripts. Solutions to the exercises are available to instructors

Description: Males of Eledone cirrhosa grow to a size little over 600 g and normally have well-developed, and presumably active, reproductive organs from about 200 g upwards. Total weight of the genital bag is well correlated with total body weight (r= 0·906). Growth of the testis precedes that of the spermatophoric sac, and the size of neither of these reproductive components is predictable from body weight. The sizes of these organs and the estimated number and length of stored spermatophores are given for 100 g intervals of total body weight. No evidence was obtained for a seasonal trend in male maturity.

Description: We present chemical data on magmatically heterogeneous pyroclastic deposits of late Quaternary age erupted from zoned magma systems underlying Tenerife (Canary Islands), Sao Miguel and Faial (Azores), and Vesuvius. The most fractionated magmas present at each centre are respectively Na-rich phonolite, trachyte, and K-rich phonolite. Within any one deposit, chemical variation is either accompanied by changes in the phenocryst assemblage (petrographic zonation) or is largely manifested in trace element abundances, unaccompanied by any petrographic change (occult zonation). Zoning is analogous to that in calc-alkaline systems where the most fractionated products are high-silica rhyolites. When a range of magma types are considered, a correlation emerges between roofward depletion of trace elements (especially REE) in the zoned system and compatability of those same trace elements in the accessory phenocryst phases present. Thus, allanite- or chevkinite-bearing rhyolitic systems are light-REE depleted roofwards, the sphene-bearing Tenerife system is middle-REE depleted roofwards, the melanite-bearing Vesuvius system is heavy-REE depleted roofwards, while the Azores systems, which lack these phases, display roofward REE enrichment. Therefore, the behaviour of trace elements may in each case be explained by fractionation of observed phenocryst assemblages. The resemblance between features of zoned magma systems and published work on the dynamic consequences of cooling saturated aqueous solutions prompts us to suggest that sidewall crystallization and consequent boundary-layer uprise to form a capping layer at top of the system may be a plausible mechanism for the generation of both petrographic and occult zonation. Reverse zoning occurs among the first-erupted tephra of some deposits, demonstrating that the most highly differentiated magma available is not always the first to be tapped during an eruption from a zoned system.

Description: Changes in the relative size of the ovary, oviducal glands and eggs are described for Eledone cirrhosa captured from the North Sea off Aberdeen over a 3 year period (N = 488). The analysis is based only on freshly caught animals, excluding those held in aquarium conditions (〉 5 days). Ovary enlargement and egg size estimates are used as indices of sexual maturity. Between 0–15% and 18–95% of total body weight is contributed by the ovary. Maximum egg length in the ovary ranges up to 7 mm. On these criteria, sexual maturation typically occurs at body sizes between 400–1000 g although some animals of 1000–1200 g are found showing no evidence of ovary enlargement. The majority of the monthly sample is always immature but maturation can apparently occur at almost any time of the year. Increase in mean ovary index and mean values for egg size are strongly seasonal and indicate a peak incidence of sexual maturity over 2–3 months in the July-September period. Spawning is presumed to follow within 1 month. Estimates of the fecundity of the females, based on the egg sample from the ovary, range from 2·2 × 103 to 55 × 10 3 eggs with a mean of 11 × 10 3 and a mode of 7·5 × 10 3 eggs.

Description: Female Eledone cirrhosa held in aquarium conditions for periods of time of five daysand over show relatively enlarged ovary sizes. Values for ovary index considerably exceed thoseof freshly caught animals and the incidence of the final stage of maturity, in which eggs pack the oviducts, is greater. A comparison of maturity indices for fresh and aquarium males was inconclusive. The range of factors associated with aquarium conditions is briefly reviewed and it is concluded that studies of cephalopod reproductive maturation must distinguish fresh and aquarium animals. Introduction External factors effective in inducing sexual maturation in cephalopods have been suggested several times. The influence of the absence of light has been implicated since the experiments of Wells & Wells (1959) showed that blinded Octopus vulgar is matured precociously. An effect of short day length in stimulating the optic glands of Sepia has been found by Defretin & Richard (1967) and Richard (1967) but this is not clearly the case for Octopus (Buckley, 1977). Octopuses kept in aquarium conditions for lengthy periods are said to have larger relative gonad sizes than those fresh from the sea (Wells & Wells, 1975). One of the factors associated with aquarium conditions is often a degree of starvation, and this circumstance alone is held to be a factor in inducing precocious sexual maturation in Eledone (Mangold & Boucher-Rodoni, 1973). In the course of recent studies on the growth and reproduction of Eledone cirrhosa from the North Sea (Boyle & Knobloch, 1982,1983,1984) animals which had remained in aquarium conditions for 5 days or over were separated from the analysis.

Description: A new species of a monogenean Isancistrum subulatae (Gyrodactylidae) has been discovered on the arms and tentacles of the cephalopod mollusc Alloteuthis subulata at Plymouth and I. loliginis, on the gills of the same host, has been re-discovered for the first time since its original description in 1912. I. subulatae, like other gyrodactylids, is viviparous, and has been shown by experiments to transfer to new hosts by contagion. In nature such transfers probably take place during copulation of the hosts and since the parasite may occur in numbers of several thousands per host, it may thereby constitute a venereal disease.

Description: Study of Nautilus belauensis i its natural habitat in Palau, West Caroline Islands, shows that growth is slow (0.1 millimeter of shell per day on the average) and decreases as maturity is approached and that individuals may live at least 4 years beyond maturity. Age estimates for seven animals marked and recaptured between 45 and 355 days after release range from 14.5 to 17.2 years. These data indicate that the life-span of Nautilus may exceed 20 years and that its life strategy is very different from that of other living cephalopods.

Description: The growth of the octopus Eledone cirrhosa has been studied in a population from the North Sea off Aberdeen. Data are presented for the growth of individuals isolated in aquarium conditions; the growth of size classes in thefieldpopulation; and preliminary information on the growth relationships of gonad, somatic, cardiac and brain components of the body. At 15 °C Eledone cirrhosa is capable of growing from 10 to 1000 g in 270 days. From octopuses which feed readily in captivity, weight specific growth rates of up to about 3–5 % day-1 for animals of 100 g body weight are recorded, falling to a maximum of about 1–5 % day-1 at body sizes above 500 g. Females stop growing when sexually mature, but in the sample captured they were consistently larger than males, a feature which may account for the 7:1 bias towards the incidence of females. On a wet-weight basis, the mean food incorporation into growth is 37 % of the food ingested, which is 49% of the gross weight of crabs killed. Field data for 1978/79 suggest that animals recruited to the population at the beginning of the year grew steadily until December, overwintered without growing, then grew rapidly for several months in the subsequent year before disappearing from the samples. The estimated average age of those animals and by implication, the life span, is 20 months.

Description: The vertical distribution of the hydromedusa Aequorea forskalea was investigated using observations from the research submersible 'Jago' collected during 36 dives off the west coast of southern Africa during November 1997 and April 1999. The mean population depth of Aequorea? forskalea deepened with increasing sea surface temperature. We suggest that this behaviour enables individuals to avoid offshore advection, to minimize spatial overlap with other large medusae and to maintain their position over the middle of the shelf.

Description: Large euhedral crystals of calcium carbonate hexahydrate were recovered from a shelf basin of the Bransfield Strait, Antarctic Peninsula, at a water depth of 1950 meters and sub-zero bottom water temperatures. The chemistry, mineralogy, and stable isotope composition of this hydrated calcium carbonate phase, its environment of formation, and its mode of precipitation confirm the properties variously attributed to hypothetical precursors of the glendonites and thereby greatly expand their use in paleoceanographic interpretation.

Description: The planktonic foraminifer Globigerinoides sacculifer (Brady) was cultured under two different light intensities and in continuous darkness. High light intensity (HLI = 4oo-soo einsteins/m2/s) resulted in a longer lifespan, a greater number of chambers formed, and a larger final shell size compared with individuals cultured under low light intensity (LLI = 20-50 einsteins/m2/s) or in continuous darkness. Shell growth rates were unaffected by increasing light intensity, but gametogenesis was delayed. Continuous darkness induced a rapid onset of gametogenesis in organisms with shell lengths larger than 250 m. Feeding frequency had a greater effect on growth and reproduction than light intensity under conditions of LLI and HLI, but continuous darkness had an overriding effect on growth and reproduction owing to the rapid onset of gametogenesis which terminated the life of the mother cell. Our previous data indicated that the longevity of G. sacculifer was dependent on feeding frequency, and that G. sacculifer cultured under LLI had a lifespan of approximately 2-4 weeks. Present results suggest that the lifespan can vary from a minimum of 8 days for organisms fed daily in continuous darkness to a maximum of 54 days for organisms fed once every 7 days and maintained in HLI. It is concluded that individual G. sacculifer attain a shell size greater than 6oo ,urn only if they maintain their position in the euphotic zone. Prolonged existence below the euphotic zone would result in premature death or gametogenesis following stunted shell growth.

Description: Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D.

Description: By amplifying the melanocortin type 1 receptor from the woolly mammoth, we can report the complete nucleotide sequence of a nuclear-encoded gene from an extinct species. We found two alleles and show that one allele produces a functional protein whereas the other one encodes a protein with strongly reduced activity. This finding suggests that mammoths may have been polymorphic in coat color, with both dark- and light-haired individuals co-occurring.

Description: Sponges (phylum Porifera) are among the most ancient of the multicellular animals, or Metazoa, with a fossil record dating back at least 580 million years (1). Found both in marine and freshwater environments, they filter-feed by pumping water through their bodies, which can contain a remarkable number of microbial symbionts. Sponges lack many of the characteristics typical of animals, but recent genomic studies—including the report by Jackson et al. on page 1893 of this issue (2)—have shown that they possess many major metazoan gene families. Sponges are thus invaluable systems for studying the evolution of metazoans and their interactions with microorganisms. Furthermore, their highly stable skeletons are of interest to materials scientists. Biomineralization is an important feature of metazoan life. Animals including vertebrates, insects, mollusks, and sponges use minerals [such as calcium carbonate, iron, and silica] to form skeletal structures such as bones, seashells, and coral reefs (3). Biocalcification arose among many metazoan lineages during the “Cambrian explosion,” between 530 and 520 million years ago, when the ancestors of today's animals first appeared in the fossil record. Did these lineages share the same gene(s) for biocalcification, or did multiple independent evolutionary events give rise to the ability to biocalcify? Recent studies, including that by Jackson et al., are beginning to provide an answer to this question. Jackson et al. use the Indo- Pacific sponge Astrosclera willeyana to show that the last common ancestor of the metazoans possessed a precursor to the α-carbonic anhydrases. This gene family is used by animals today in a range of processes including ion transport, pH regulation, and biomineralization (4). By integrating molecular techniques ranging from protein sequencing to gene expression, the authors identified a group of closely related α-carbonic anhydrase sequences in A. willeyana. These sequences are similar to those recovered from a whole-genome project on another sponge, Amphimedon queenslandica (5). Together, the sponge α-carbonic anhydrases form a sister group to those of all other metazoans.

Description: The Atlantic meridional overturning circulation (MOC), which provides one-quarter of the global meridional heat transport, is composed of a number of separate flow components. How changes in the strength of each of those components may affect that of the others has been unclear because of a lack of adequate data. We continuously observed the MOC at 26.5°N for 1 year using end-point measurements of density, bottom pressure, and ocean currents; cable measurements across the Straits of Florida; and wind stress. The different transport components largely compensate for each other, thus confirming the validity of our monitoring approach. The MOC varied over the period of observation by ±5.7 × 106 cubic meters per second, with density-inferred and wind-driven transports contributing equally to it. We find evidence for depth-independent compensation for the wind-driven surface flow.

Description: Draining of a huge lake into the Northern Atlantic may have triggered a cold period ~12,900 years ago. The route taken by the flood waters remains unknown.

Description: The open oceans comprise most of the biosphere, yet patterns and trends of species diversity there are enigmatic. Here, we derive worldwide patterns of tuna and billfish diversity over the past 50 years, revealing distinct subtropical "hotspots" that appeared to hold generally for other predators and zooplankton. Diversity was positively correlated with thermal fronts and dissolved oxygen and a nonlinear function of temperature (~25°C optimum). Diversity declined between 10 and 50% in all oceans, a trend that coincided with increased fishing pressure, superimposed on strong El Niño–Southern Oscillation–driven variability across the Pacific. We conclude that predator diversity shows a predictable yet eroding pattern signaling ecosystem-wide changes linked to climate and fishing.

Description: Ocean island volcanoes frequently develop local rift zones associated with flank movement and flank collapses. The ocean island El Hierro grew by coalescence and collapse of three volcanic edifices, which are an elongated topographic ridge (the Southern Ridge) and two semi-circular volcanic cones (Ti˜nor volcano, El Golfo volcano). During edifice growth and volcano coalescence, eruption fissures nucleated into rift zones that developed a complex triangle pattern. In scaled analogue experimentswe could successfully reproduce the geometry of rift zones and unstable flanks as observed on El Hierro. The experimental results suggest that the rift configuration on El Hierro is the result of gravitational volcano spreading over deformable basal substrata, rather than of deep-seated magma updoming as thought previously. This paper elucidates the importance of the basal substratum and gravitational spreading, and the relationship to rifting and flank instability on El Hierro Island, and may help in understanding similar volcano architectures elsewhere.

Description: This paper documents the arrival of Diplosoma listerianum into a habitat with no previously known history of the species. Once established, D. listerianum exploited rapid growth rates relative to the other fouling species present, to quickly become the dominant species in a local fouling assemblage. Most resident macrofoulers were out-competed for space and overgrown, although some resistance to overgrowth was demonstrated by the bryozoan Umbonula littoralis and the tunicate Ascidiella aspersa. In this instance, traits traditionally considered to be relevant for community resistance towards invasion, such as diversity, richness, dominant species identity and open space were not important in controlling the spread of D. listerianum

Description: The vigor of Atlantic meridional overturning circulation (MOC) is thought to be vulnerable to global warming, but its short-term temporal variability is unknown so changes inferred from sparse observations on the decadal time scale of recent climate change are uncertain. We combine continuous measurements of the MOC (beginning in 2004) using the purposefully designed transatlantic Rapid Climate Change array of moored instruments deployed along 26.5°N, with time series of Gulf Stream transport and surface-layer Ekman transport to quantify its intra-annual variability. The year-long average overturning is 18.7 ± 5.6 sverdrups (Sv) (range: 4.0 to 34.9 Sv, where 1 Sv = a flow of ocean water of 106 cubic meters per second).

Description: Calcareous tube polychaetes (family Serpulidae) are notorious biofoulers that are easily transported and introduced to allochthonous habitats. Here we report the recent introduction of Hydroides dianthus (Verrill, 1873) to eastern Japan as its first occurrence in East Asia, probably from European or American coasts. Specimens had been found on artificial hard substrata together with congeners H. ezoensis, H. exaltatus and H. fusicolus in Tokyo Bay, Japan in 2006. The origin, vector, source of introduction and possible impact of H. dianthus on Japanese coasts is discussed from a perspective based on worldwide Hydroides transport.

Description: One of the mysteries regarding Earth’s climate system response to variations in solar output is how the relatively small fluctuations of the 11-year solar cycle can produce the magnitude of the observed climate signals in the tropical Pacific associated with such solar variability. Two mechanisms, the top-down stratospheric response of ozone to fluctuations of shortwave solar forcing and the bottom-up coupled ocean-atmosphere surface response, are included in versions of three global climate models, with either mechanism acting alone or both acting together. We show that the two mechanisms act together to enhance the climatological off-equatorial tropical precipitation maxima in the Pacific, lower the eastern equatorial Pacific sea surface temperatures during peaks in the 11-year solar cycle, and reduce low-latitude clouds to amplify the solar forcing at the surface.

Description: The oceans are a major sink for atmospheric carbon dioxide (CO2). Historically, observations have been too sparse to allow accurate tracking of changes in rates of CO2 uptake over ocean basins, so little is known about how these vary. Here, we show observations indicating substantial variability in the CO2 uptake by the North Atlantic on time scales of a few years. Further, we use measurements from a coordinated network of instrumented commercial ships to define the annual flux into the North Atlantic, for the year 2005, to a precision of about 10%. This approach offers the prospect of accurately monitoring the changing ocean CO2 sink for those ocean basins that are well covered by shipping routes.

Description: During an almost yearlong period of observations made with a current meter in the fracture zone between the Falkland Islands (Islas Malvinas) and South Georgia, several overflow events were recorded at a depth of 3000 meters carrying cold bottom water from the Scotia Sea into the Argentine Basin. The outflow bursts of Scotia Sea bottom water, a mixing product of Weddell Sea and eastern Pacific bottom water, were associated with typical speeds of more than 28 centimeters per second toward the northwest and characteristic temperatures below 0.6°C. The maximum 24-hour average speed of 65 centimeters per second, together with a temperature of 0.29°C, was encountered on 14 November 1980 at a water depth of 2973 meters, 35 meters above the sea floor.

Description: Five hundred and twenty-eight specimens of Loligo forbesi Steenstrup, from landings in Horta, Faial, Azores, during the year 1 March 1980 to 28 February 1981, were tudied; 59·3 % were males, 40·7 % females. Of the males 80·2 % were sexually mature, of the females 91·6 %, both sexes showing the highest degree of maturity in spring and he lowest in autumn. The mean dorsal mantle length of the mature males was 56·5 cm, or females 33·5 cm. A weight-length relationship was calculated. he stomachs of 622 specimens were sampled, of which 306 contained food. The prey omponents were studied qualitatively. The main prey was fish (82·0%), of which 0·5 % were horse mackerel, Trachurus picturatus, this being the most important food rganism. Preliminary results of statolith readings are given.

Description: Symbiotic luminous bacteria have been described in, and cultured from, a number of species offish and cephalopod. Indeed only in these two groups are extracellular luminous bacteria believed to be utilized as a source of light (see Buchner (1965) and Herring (1978) for references). Despite several earlier investigations of such symbioses in cephalopods the bacteria in these animals have not been adequately identified, nor has the extent of their role been clarified. The ultrastructural relationships between bacteria and the tissues of the squid accessory nidamental gland have been investigated in the non-luminous species Loligo pealei (Lesueur) (Bloodgood, 1977) and Sepia officinalis L. (Van den Branden et al. 1979) but no comparative work on luminous species has been undertaken apart from that on Heteroteuthis dispar (Rüppell), whose photophore does not contain typical luminous bacteria (Dilly & Herring, 1978; cf. Leisman, Cohn & Nealson, 1980). The order Sepioidea contains five families, among which are the two families Sepiolidae and Spirulidae. Though the presence of luminous bacteria is known in some sepiolids (as well as in certain loliginids (order Teuthoidea)) some doubt remains about the source of light in the photophore of Spirula spirula Hoyle. The steady luminescence of this species has prompted speculation that bacteria may be involved (Harvey, 1952). In this paper we compare the anatomy and ultrastructure of the photophores of both Sepiola and Spirula in order to clarify some of these problems.

Description: This is the first detailed analysis of cephalopod beaks from the stomach of a northern bottlenosed whale, Hyperoodon ampullatus (Forster, 1770). The digestive action of many predators barely affects the chitinous beaks of cephalopods and some cetaceans accumulate the beaks in considerable numbers in their stomachs. The present beaks are clean and unbroken. Identification of cephalopod beaks from stomachs of predators such as sperm whales (see Clarke, 1977), seals (Clarke & Trillmich, 1980) and albatrosses (Clarke, Croxall & Prince, 1980) throws considerable light on the biology and relative ecological importance of the species of cephalopods concerned as well as providing useful information on the diet of the predators.

Description: Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2°C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef-associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled-up management intervention and decisive action on global emissions are required if the loss of coral-dominated ecosystems is to be avoided.

Description: Picoeukaryotes are a taxonomically diverse group of organism less than 2 micrometers in diameter. Photosynthetic marine picoeukaryotes in the genus Micromonas thrive in ecosystems ranging from tropical to polar and could serve as sentinel organisms for biogeochemical fluxes of modern oceans during climate change. These broadly distributed primary producers belong to an anciently diverged sister clade to land plants. Although Micromonas isolates have high 18S ribosomal RNA gene identity, we found that genomes from two isolates shared only 90 of their predicted genes. Their independent evolutionary paths were emphasized by distinct riboswitch arrangements as well as the discovery of intronic repeat elements in one isolate, and in metagenomic data, but not in other genomes. Divergence appears to have been facilitated by selection and acquisition processes that actively shape the repertoire of genes that are mutually exclusive between the two isolates differently than the core genes. Analyses of the Micromonas genomes offer valuable insights into ecological differentiation and the dynamic nature of early plant evolution.

Description: Cephalopod statoliths are paired calcareous stones which lie in cavities, the statocysts, within the skull. They have a form which, though variable, shows promise as a source of criteria for taxonomic and evolutionary studies. As a preliminary to more detailed studies, Clarke (1978) published a description of the form of a generalized teuthoid statolith, coined nomenclature for the various parts and gave a very brief survey of variation of statoliths within the living Cephalopoda. This nomenclature was used in a detailed description of fossilized teuthoid statoliths by Clarke & Fitch (1979). Here, descriptions of the statoliths of the living species Berryteuthis magister (Berry, 1913), Gonatopsis borealis Sasaki, 1923, Gonatopsis (Boreoteuthis) makko Okutani & Nemoto, 1964 and Gonatus fabricii (Lichtenstein, 1818) are given and the fossil Berryteuthis species described in outline by Clarke & Fitch (1979) is compared with B. magister. A statistical analysis of measurements of the statoliths of these five species has been made and the results are presented. This forms the first part of a general description of teuthoid statoliths and similar studies on the Ommastrephidae and the Loliginidae are in preparation.

Description: A total of 104 Semirossia patagonica were collected all over the Patagonian shelf between the depths of 47 and 295 m. Mature female size varied from 10 to 35 mm ML, mature male size was 16–32 mm. Potential fecundity ranged between 527–766 eggs in pre-spawning females, ripe egg size was 3.4–5.0 mm. The oviduct capacity probably was no more than 30 eggs. The maximum number of spermatophores in males was 229. Males transfer 2–19 spermatophores to females during copulation. The ovulation pattern is asynchronous, individual spawning is continuous. Reproduction occurs all year round. Semirossia patagonica is a south-west Atlantic ecological sibling of north-east Atlantic bobtail squids Sepiola spp. and Sepietta spp.

Description: Recent scientific and commercial deepwater trawls provide evidence that the loliginid squid, Loligo gahi occurs much deeper than previously believed. Three immature and maturing squids were caught in two hauls between 528 and 626 m depth, exceeding the previous maximum recorded depth of 400 m. An L. gahi egg mass was found on the bottom attached to polychaete tube sampled from depths of 68–71 m. It represents a new spawning habitat, because before the species was known to spawn only in inshore kelp forests, well off the bottom, at depths 〈20 m.

Description: Fossilized argonaut egg cases have been recovered from marine siltstones of the late Miocene exposed around margins of the Los Angeles Basin, California. Low radial ribs on the thin, keelless, planispirally coiled egg cases suggest referring them to Mizuhobaris lepta new species. Occurrence of these egg cases in fine-grained Monterey Formation sediments with mesopelagic fish fossils, nannofossils, and Foraminifera indicate deposition in middle-to-upper bathyal depths. Argonaut egg cases have been described from Tertiary strata in Japan, New Zealand, Sumatra, and Europe, but this is the first report of fossilized argonaut egg cases from the Western Hemisphere. Secretion of egg cases by argonauts probably developed during the Paleogene as a solution to problems of spawning encountered by octopi as they acquired an epipelagic, open-ocean habitat. Shape and sculpture of the egg cases represent responses to hydrodynamics rather than an inheritance from or copying of ectocochliate cephalopods. The cases may provide the eggs with protection from ultraviolet radiation present in the argonauts' near-surface habitat.

Description: Here we report bipedal movement with a hydrostatic skeleton. Two species of octopus walk on two alternating arms using a rolling gait and appear to use the remaining six arms for camouflage. Octopus marginatus resembles a coconut, and Octopus (Abdopus) aculeatus, a clump of floating algae. Using underwater video, we analyzed the kinematics of their strides. Each arm was on the sand for more than half of the stride, qualifying this behavior as a form of walking.

Description: The jumbo or Humboldt squid, Dosidicus gigas, is an important fisheries resource and a significant participant in regional ecologies as both predator and prey. It is the largest species in the oceanic squid family Ommastrephidae and has the largest known potential fecundity of any cephalopod, yet little is understood about its reproductive biology. We report the first discovery of a naturally deposited egg mass of Dosidicus gigas, as well as the first spawning of eggs in captivity. The egg mass was found in warm water (25–27°C) at a depth of 16 m and was far larger than the egg masses of any squid species previously reported. Eggs were embedded in a watery, gelatinous matrix and were individually surrounded by a unique envelope external to the chorion. This envelope was present in both wild and captive-spawned egg masses, but it was not present in artificially fertilized eggs. The wild egg mass appeared to be resistant to microbial infection, unlike the incomplete and damaged egg masses spawned in captivity, suggesting that the intact egg mass protects the eggs within. Chorion expansion was also more extensive in the wild egg mass. Hatchling behaviours included proboscis extension, chromatophore activity, and a range of swimming speeds that may allow them to exercise some control over their distribution in the wild.

Description: European Marine Biology Symposium. 15 1981 Abstract Mass accumulations of filamentous blue-green algae in surface waters of the Baltic Sea cause patches of high bacterial productivity within water masses of low microbial activity. Since these algae are apparently not grazed by zooplankton organisms, their degradation in the surface water layer is mainly due to associated bacteria. The network of algae filaments attracts a wide range of small organisms including rotifers, crustaceans, ciliates and flagellates, resulting in a microbiotope of considerable complexity. The succession of bacterial colonization of Nodularia spumigena and the activity state of the community was investigated by the INT-staining technique and by microautoradiography. The excretion rates of photosynthesized matter by the bluegreen algae agglomerates indicate a high rate of transfer of substrate towards the adherent heterotrophic bacteria. The fate and the final involvement of the agglomerates in the food chain are discussed.

Description: A new technique for the harmonic analysis of current observations is described. lt consists in applying a linear band pass filter which separates the various species and removes the contribution of non-tidal effects at intertidal frequencies. The tidal constituents are then evaluated through the method of least squares. In spite of the narrowness of the fitter, only three days of data are lost through the filtering procedure and the only requirement on the data is that the time interval between samples be an integer fraction of one day. This technique is illustrated through the analysis of a few French current observations from the English Channel within the framework of INOUT. The characteristics of the main tidal constituents are given.

Description: 14C concentrations, as weil as 13C, hydrographic and nutrient data are reported for 5 hydrographic stations that form a transatlantic section near 40° N ("Meteor" cruise no. 23, 1971). Precision (for 14C ± 0.3% or better) and comparability with literature data are specified. A planned intercomparison with the US GEOSECS program within the Newfoundland Basin deep water failed because of variability of water characteristics. The observed 14C values decrease from about Δ 14C = + 80‰ at the surface to -70‰ at 2000 m depth. Deeper down, the values west of the Midatlantic Ridge remain similar, whereas those east of the ridge decrease further, to about -110‰. It is shown that bomb-14C is prominent down to about 1500 m depth. Beyond this depth the bomb 14C component is small and is negligible in the eastern basin below 2800 m. On the basis of the 14C-tritium correlation, the distribution of natural 14C below about 1500 m depth is derived from the observations. In the deep and bottom water east of the ridge the 14C-salinity relationship seemingly is non-linear. Contrary to expectation, the 14C concentration in the bottom water is not lower than found on an US GEOSECS station near 10° N. Apparently, lateral concentration differences in the Northeast Atlantic bottom water as well as nonlinearity of the 14C-salinity relationship at 40°N do not exceed 10‰ in Δ 14C.

Description: The grazing of different copepodite stages of Calanus finmarchicus on natural phytoplankton populations was measured at different times of day and night during the Fladen Ground Experiment (FLEX), from the end of May to the beginning of June 1976, at the central position of the "FLEX box" (58° 55' 00" N, 0° 32' 05" E), on board of the R.V. "Meteor". A big difference between nocturnal and diurnal food intake was found, particularly for the stages V & IV, which at night ingest 4 to 10 times more than during daytime. The maximal daily food intake (24 hours), taking into account the different feeding rates at the different times of the day and expressed as percent of own carbon weight, was found to be 31 %, 83 %, 115 % and 148 % for the copepodite stages V, IV, III, II and I together, respectively, with an initial feeding threshold at about 50-60 µg C · l-1. The total grazing for the upper 40 m depth layer was calculated for each sampling time; a very pronounced grazing rhythm was found, due to the higher ingestion rates at night combined with the vertical migrations. Maximal night ingestions were 100-200 mg C/m2/hour at the end of May to 300-400 mg C/m2/hour at the beginning of June, compared with 1-20 mg C/m2/hour at midday. Making a balance of the positive influence of particulate primary production and the negative influence of grazing on the stock of particulate carbon, we could show that the main cause of the decline of the phytoplankton bloom in this period was Calanus grazing. Other zooplankton activities, namely respiration, production and faecal pellets excretion as measured by four other authors are in balance with our results of ingestion.

Description: "Auftrieb 75" was a joint cruise of R.V. "Meteor" and R.R.S. "Discovery" performed in the area 21-26° N off the northwest African coast during January-March, 1975. Current meter observations from six moorings and CTD/STD observations from three repeatedly covered sections of the cruise are analysed in order to describe the distribution of the water masses and its variability with the changes in the current system. The Canary Current is seen to pass through the northwestern corner of the expedition area, carrying with it a geostrophic eddy with a period in excess of 30 days. The eddy is probably another example of the type generally found in the open ocean circulation. Further south, offshore currents display large variations in strength and direction with a typical time scale of 10-14 days which are believed to reflect largescale mixing processes along the boundary of the Canary Current and the poleward flow of the coastal region, involving North Atlantic Central Water (NACW) and South Atlantic Central Water (SACW). The coastal upwelling undercurrent has been observed along the shelf edge but undergoes large variations in response to the wind and to variations in the horizontal divergence of the offshore currents. On the shelf the circulation responds to the local longshore wind to some extent but is also strongly affected by variations of the currents at the shelf edge. The distribution of water masses at intermediate depth ( 100-800 m) is analysed quantitatively based on the assumption that mixing between NACW and SACW is effective along surfaces of constant density only. lt is shown that most intense mixing occurs at about 22-23° N and is still very important further south. At 25-26° N SACW has been absorbed into the surrounding NACW water mass to a high degree, even in the undercurrent. Isolated bodies of water are found in the southern part of the expedition area, some of which are carried north in the undercurrent. The large variability in the water mass distribution at the source level of the upwelling probably has important consequences for the variations in the efficiency of biological production of the upwelling region.

Description: The main objectives of the Fladen Ground Experiment (FLEX) 1976 were an investigation of the dynamics of the mixed layer and the development of the spring plankton bloom. A quantitative consideration of individual chemical parameters (nutrients, particulate nitrogen and phosphorus) showed it to be advantageous to divide the water column into several layers which are separated from one another by measured temperature gradients. Measurements of particulate matter (phosphorus and nitrogen) revealed two plankton blooms at the central station. The first one (21.4.-14.5.76) was much more extensive than the second one, since the limiting thermocline was at a depth of about 60 m. Silicate was consumed most rapidly during this bloom and almost completely exhausted. The second bloom (19.-30.5.76) produced concentrations of particulate matter which were almost as high as the first one but were limited in only a few meters' water depth by a secondary thermocline, which prevented an influx of nutrients. Nitrate was completely exhausted during the second bloom. A high degree of nutrient depletion in the mixed layer from 24.4.-29.4. and from 22.5.-27.5.76 make these periods appear well-suited for determination of uptake rates. These periods are characterized. by a parallel course of concentration curves in the upper water layers for all nutrients except ammonium, and by the absence of !arge short-term fluctuations. Thus, disturbances due to hydrodynamic effects were minimal. The effects of tidal changes were minimized by using daily averages of the various concentrations. However, from 9.5.-13.5.7 6 in the upper layer a relatively strong and rapid increase was observed in the concentrations of all nutrients, which can probably only be explained by hydrodynamic influences. The nitrogen and phosphorus budgets can only be approximately balanced without considering dissolved organic matter. The strong decrease in dissolved inorganic nutrients during the first plankton bloom is almost comple,tely compensated by the increase in particulate matter. Not considering hydrodynamic influences, deficits after the plankton bloom could be explained by the fact that dissolved organic substances, as weil as sedimentaty matter and zooplankton, either were not considered at all, or at least not quantitatively. The time periods from 2.-7.4. and from 21.4.-14.5.76 show no strong short-term fluctuations in the nitrogen and phosphorus budgets and appear most suitable for calculations of mass fluxes, uptake and production rates, since biological-chemical processes seem to be dominant over hydrodynamic ones during these periods.

Description: The monthly mean meteorologically induced circulation of the North Sea for the period 15 March to 15 April 1976 (JONSDAP '76 INOUT period) is computed using two numerical models. One has a fine grid resolution, is two-dimensional, comprehensively non-linear and covers the North Sea. The other has a coarser grid resolution, is three-dimensional, and linear except for the inclusion of quadratic bottom friction. The depth variation of the two horizontal components of current in this model is accomplished using an expansion of time and horizontally dependent coefficients and depth dependent functions. The three-dimensional modelling technique presented here is sufficiently flexible to allow an arbitraty space and time variation of vertical eddy viscosity, although still retaining a continuous representation of current in the vertical, and allowing for variable bottom topography. Preliminary results presented here for the meteorologically induced circulation of the North Sea during JONSDAP '76 agree weil with present knowledge of the circulation of the North Sea. Comparing surface and bottom currents computed with the 3 D shelf model, it is evident that the windinduced flow varies considerably in both magnitude and direction between sea surface and sea bottom. The distribution of depth mean current computed with the 3 D shelf model over the North Sea is nearly identical to that computed with the 2 D North Sea model. This is particularly encouraging since the 3 D shelf model does not contain the advective terms, which are present in the 2 D model, and has a coarser resolution.

Description: The ecology of the lower marine fungi, namely the thraustochytrids, in the Fladen Ground area (FLEX box) and other parts of the North Sea was studied during 5 cruises in 1975 and 1976. The number of fungi/liter and the number of species showed seasonal fluctuations in the surface water samples from all the stations. A high number was found in September 1976 and a low number in March 1976. These numbers, however, revealed no seasonal fluctuations in the underlying sediments. In both the surface waters and the sediments, a consistently low number of fungi was recorded for certain stations and a high number of fungi for others, the reason for this being unknown. The sediments revealed a very high number of fungi/liter. Observations on the distribution of various species are presented. Certain species occurred more frequently at some stations than at others; certain species occurred more in the water column, e. g. Ulkenia minuta, and still others in the sediments, e. g. Thraustochytrium multirudimentale.

Description: In the framework of the Fladen Ground Experiment 1976, zooplankton samples were taken during the phytoplankton spring bloom in April-May and after the bloom in June. The plankton was collected with two samplers, a towed multiple high-speed sampler and a newly developed swing net for local sampling. The results of both methods are compared. The mean number and dry weight per m3 are given for the common species, as weil as the density of fecal pellets. The calanoid copepod Calanus finmarchicus formed 63 %, resp. 90 % of the biomass. The population composition, distribution, dry weight/length relationship and productivity of this species is studied in more detail. The high abundance of fecal pellets, eggs and young stages during the spring bloom indicate a high zooplankton activity in this period. The low density of these indicators and the apparent descent of the older Calanus stages to deep water layers in June signify the dependency of the zooplankton activity on the phytoplankton density. The estimated daily production of Calanus during the phytoplankton bloom was 20 mgC/m2. The significance of the seasonal vertical migration and the role of zooplankton in the northern North Sea ecosystem is discussed. lt is concluded that the Zooplankton could have checked the low algal density in May-June after the spring bloom, but it is far from certain that it stopped the phytoplankton outburst at the end of April and early May.

Description: During the culmination of the phytoplankton spring bloom in the Fladen Ground area in April-Mai 1976, gross primary production was between 1500 and 2000 mg particulate C m-2 day-1, at a crop density (mainly diatoms of the genus Chaetoceros) of about 1500-3500 mg C m-2. Estimates of the C : chlorophyll a ratio in living cells were much lower than those reported in the literature, possibly because part of what is measured as "chlorophyll a" by the common fluorometric method is associated with particles that are not reported as cells. Most of the dark 14C fixation during the bloom's climax was due to abiotic processes. Excretion of 14C-labeled carbohydrates did not account for a significant fraction of the total photosynthetic rate. The low crop after the bloom period, in June, corresponded with nutrient depletion of the euphotic zone. The low photosynthetic efficiency in June may have been a gross underestimate. The presence of relatively high concentrations of chlorophyll derivatives signifies that the algal crop was consumed by heterotrophs, but at a lower rate in April/May than during the June cruise when particularly high molar ratios of phaeophorbide a and phaeophytin a relative to chlorophyll a were found. The high respiratory rate relative to autotrophic production in June manifested itself also in high dark 14C fixation values. The high concentration of phaeophorbide a in the upper 40 m and its scarcity below this depth during the spring bloom climax in April/May implies that copepod grazing at that time took place principally in the euphotic zone. The remarkably high concentration of chlorophyllide a in the surface layer during the bloom period indicates that the part of the crop that was destroyed by the grazers while eating was occasionally as high as the part that was actually ingested.

Description: During the Fladen Ground Experiment (FLEX, March 26-June 6, 1976) quantitative investigations of herbivorous zooplankton were performed. For that purpose 1785 water samples (5 or 10 l) were taken with a rosette sampler at the central station (pos. 58° 55' N, 0° 32' E) from nine to ten standard depths and filtered through 30 µm gauze filters. The development of the most important Zooplankton groups at the central Station is presented in depth-integrated time series (0-100 m) of individuals per m2. The number of individuals of Calanus finmarchicus was converted to biomass (dry weight). At the end of the sampling at the central station the standing stock of Calanus finmarchicus showed about 18 g dry weight per m2. Numerical values for the time lags between different plankton groups are calculated with the aid of the cross-correlation function. The time lag between the diatom ad copepod egg peaks is only up to 2.75 days; that between diatoms and the larvae of bottom invertegrates is 5 days. Between the copepod eggs and the maximum number of nauplii (N I-N VI) there is a time lag of 10.75 days. Another 10.25 days lie between the maximum numbers of nauplii and copepodites (C I-C VI). Considering the depth-integrated time series of the abundance of Calanus finmarchicus copepodites, a succession of the Stages seems to exist. Nevertheless, numerical values for the time lags between the different developmental stages cannot be calculated unambiguously by the cross-correlation technique. This is probably caused by extreme simultaneous fluctuations, especially of the numbers of all stages of Calanus finmarchicus in the last phase of the sampling at the central station.

Description: The third phase of the cooperative data collection program JONSDAP begun in 1970 by the countries bordering on the North Sea was planned to include for the first time biological and chemical measurements in 1976, as well as physical ones. Intensive measurement programs were performed, one concentrating on the currents flowing into and out of the open boarders of the North Sea (INOUT) for 40 days in March/ April and one in which the dependence of the spring plankton bloom on the vertical temperature structure was studied in the Fladen Ground area for 100 days from March to June (FLEX). Around 90 % of the planned program with moored systems and 75 % of the measurements from moving ships were able to be carried out successfully. The large quantities of data required the establishment of two data centers. The current data were collected in Liege, all data from the FLEX box in Hamburg. A cooperative JONSDAP format was agreed on for the exchange of data. Graphic presentations of the data have been compiled in the two-volume Draft FLEX/IN OUT Atlas and distributed to all JONSDAP '76 participants, one of the main purposes of which being the facilitation of interdisciplinary evaluations, now that the intradisciplinary data processing has almost been completed - as presented in this volume.

Description: Measurements of nutrients and the elements phosphorus and nitrogen from the central station in FLEX '76 were used to calculate mass fluxes and budgets for these elements in defined time and depth intervals. The intervals were defined using hydrodynamic and biological criteria. Within these periods rates of increase and decrease were calculated for nitrate, ammonium, phosphate, particulate nitrogen and phosphorus. These rates were also calculated for the layer above and below the main thermocline. The element budget was balanced within some of the defined intervals. This was possible by only considering biological, chemical, and vertical physical interactions at the central station. At the beginning of the phytoplankton bloom we found fluxes with a maximum of 28 ngat · l-1 · d-1 for phosphorus and 590 ngat · l-1 · d-1 for nitrogen. Interaction diagrams are shown for mass fluxes for three periods during the plankton bloom.

Description: Since both German research vessels „Meteor" played a major role in G. Dietrich's work, it seemed appropriate to present his bibliography in this series. An assessment of his scientific achievements was given at an earlier date (H. U. ROLL 1973: In memoriam GüNTER DIETRICH 1911-1972. - ,,Meteor" Forsch.­ Ergebn. A, No. 12: V-X).

Description: Vertical velocity spectra can be determined by three different indirect methods: Following isopycnal surface displacements, following isothermal surface displacements, or calculating water particle displacements from temperature time series at fixed pressure levels, with the mean vertical temperature gradient used for the conversion factor. This third method is the easiest to perform. Data from GATE 1974, obtained by CTD profiling onboard R. V. "Meteor" and by temperature measurements on moorings, are used to check whether the three methods are equivalent. lt is shown that autospectra do not differ significantly within the 95 % confidence intervals, and either method can be applied. This does not infer an equivalence with respect to the actual data points since individual events were found in the low-passed time series with deviations occurring between displacement curves obtained by the different methods. These events were apparently due to the advection of another water mass.

Description: The research programmes of the German groups in JASIN 1978 are summarized, comprising projects that concern the planetary boundary layer, the radiation budget, the oceanic mixed layer and thermocline and the trace element exchange. Lists of the participating scientists and technicians are included. Brief descriptions of the field activities on board the three ships and the aircraft are given, including maps and stations lists.

Description: A first survey of the entire temperature data base from the central station is presented. The development and the changes of the sea surface temperature, the thermocline, and the heat content due to meteorological forces, are described.

Description: A description is given of part of the data on residual currents which were obtained during the INOUT phase of JONSDAP '76. This current measuring programme was the result of a concerted effort of North Sea bordering countries and was aimed at a better understanding of residual water movements in the North Sea. One of the first results of INOUT is the possibility to compare estimates of simultaneously occurrmg inflow/outflow through several North Sea boundary sections. It appears that major inflow/outfow occurs in the neighbourhood of the Norwegian Trench. Estimates for other boundaries are significantly lower. Matching the objectives of INOUT several charts are presented showing measured residual water movements under influence of some "persistent" winds that is to say, during situations with spatial homogeneous windfields not changing too rapidly in time. Under such conditions it is possible to identify residual current systems. However, as can be expected, in cases of spatially inhomogeneous winds and/or winds changing rapidly in time it is harder to interpret the current measurements. In those cases it is necessary to use mathematical North Sea models with the proper wind field input. The Royal Netherlands Meteorological Institute (KNMI) took care that these windfields were stored on magnetic tape during INOUT for this purpose.

Description: Recordings were made of the voltage differences between the ends of two submarine cables crossing the Pentland Firth; the recordings covered the period from February to October 1976 and thus included the period of the JONSDAP '76 oceanographic experiment in the North Sea. The noise level on these recordings was found to be greater than for similar recordings on cables crossing the Dover Strait and the North Channel of the Irish Sea; reasons for this increased noise level are discussed. Tidal analyses of the recordings were made for six discrete sets of recordings, each of 29 days duration; these analyses produced consistent results for the five major semi-diurnal constituents, namely N2, V2, M2, S2 and K2. However, an examination of the propagation of the M2 tidal constituent in this region showed that the phase of M2, as calculated from the cable recordings, did not obviously aeeord with the ove1·all pattern of propagation of that constituent. Tentatively it was concluded that cable measurements represent the integrated effect of flow over an area surrounding the Pentland Firth where this flow varies widely in both phase and direction. A calibration coefficient for the cable, relating voltage to flow, was calculated by equating the annual variation in the amplitude of the M2 constituent (measured by the cable) with the annual variation in the conduetivity of sea water in the region. The residual component of cable voltage was compared with residual components of (a) the sea surface elevation at Wick and (b) currents derived from current meter measurements at a nearby location in the North Sea; also with wind recordings at Wick. These comparisons indicated that there was neither a significant wind-driven flow through the Pentland Firth, nor a seasonally varying residual flow. It is suggested that a significant component of both the residual flow (as measured by the cables and by the current meters) and the residual elevations at Wick is associated with the propagation of "external surges" into this region.

Description: A simple model is used to simulate the dynamics of phytoplankton and phosphate from April 19 to May 16 during the Fladen Ground Experiment. The model describes the development of vertical profiles in time. lt allows changes of phytoplankton standing stock by turbulent diffusion, sinking of cells, primary production, respiration, mortality and grazing, and changes of phosphate concentration by turbulent diffusion, nutrient uptake and remineralization. The model is used as a means of checking the consistency of the biological assumptions made with the observed phosphate concentration, phytoplankton cell counts and primary production. Local turbulent diffusion coefficients, underwater light climate and Zooplankton standing stock in terms of total copepods are given quantities, the former from a physical upper layer model, the latter two from data. Simulations show that if phytoplankton standing stock and primary production are reproduced fairly well, then phosphate is still too high and vice versa. lt appears that the conversion factor expressing the amount of phosphate necessary to produce l g carbon is crucial. Relating this ratio to the observed decrease of phosphate and the primary production the simulation reproduces the exponential growth phase weil but fails for the rest. This indicates the need of a variable conversion factor in the model, depending on the status of the bloom. lt can be shown that turbulent diffusion is indispensable for the development of the spring bloom. Further it is shown that as a consequence of the assumptions made about two thirds of primary production are taken up by zooplankton. An estimate of potential grazing of copepods shows that copepods starve or have other food sources than living phytoplankton.

Description: The figures contain section data of S, t, total P, N03, chlorophyll a, total particulate P and total phytoplankton. The data indicate that primary production had started only along Norway, probably due to the high stability caused by the presence of water of Baltic origin. Three runs were made; differences between them are discussed in relation to results of current measurements.

Description: Tracking a balloon with a single ship-based theodolite, is a method which has been used for a long time to determine the wind profile over the sea. There are two main sources of error: (a) the incorrect estimate of the height of the balloon and (b) the pitch and roll motions of the ship. In this paper the effects of both errors are investigated. The ship's motion is simulated with use of a transformation from a fixed (earth) to a moving (ship) coordinate system. Some examples are presented to illustrate the magnitude of these effects.