Biological consequences of marine pollution with special reference to the North Sea fisheries

Summary 1. A case of copper pollution on the Dutch coast is used to demonstrate that waste disposal in inshore waters can easily lead to damage to the living resources of the sea, since dilution is under such conditions a much slower process than is usually assumed.2. Pollution by domestic sewage, its direct hazards for human health, and its contaminating effect on shellfish, is discussed. Next to these direct and indirect health hazards, discharge of domestic waste may lead to eutrophication, which in its turn can contribute to the development of plankton blooms producing truly poisonous metabolites. Some examples of eutrophication of the marine environment are given.3. Of the industrial waste, examples are given which clearly demonstrate how dangerous discharge of heavy metals and pesticides can be, also in the marine environment. Possible effects of petrochemical waste products and of synthetic detergents and soaps are discussed.4. Radio-active waste disposal in sea is more carefully studied and monitored than disposal of other types of waste.5. The increasing quantity and variety of industrial waste is a reason for serious concern. Careful discrimination between the many products is advocated and discharge far offshore is advised for certain categories of pollutants. Pesticides and other very dangerous products should never be admitted in the shallow sea areas, so important as nursery grounds for the fishery resources.

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Biologische Konsequenzen der Meerwasserverschmutzung unter besonderer Berücksichtigung der Nordseefischerei

Kurzfassung Obwohl das Gesamtvolumen der Ozeane erheblich größer ist als der Süßwasservorrat der Welt, so kann doch das hemmungslose Einbringen von Haus- und Industrieabwässern in das Meer zu schädlichen Folgen für den Bestand der Meeresflora und -fauna führen. Besonders anfällig sind die Küstengewässer, da diese oft die Ernährungsgrundlage für viele Nutzfische bieten und zudem dort Austern und Miesmuscheln gezüchtet werden. Aus wirtschaftlichen Gründen erfolgt andererseits das Verklappen von Abfall und Unrat vorzugsweise dicht unter der Küste. Schädliche Wirkungen können erfolgen durch Bakterien- und Virusinfektionen, durch biologische Akkumulation von Schwermetallen und von Schädlingsbekämpfungsmitteln (unter ihnen besonders chlorhaltige Kohlenwasserstoffe), durch petrochemische Produkte, wodurch übler Geschmack bei Fischen und Muscheln hervorgerufen wird, und durch eine allgemeine Eutrophierung, die zu einer Vermehrung von unerwünschtem Plankton führen kann.

     

The epidemiology of hydatidosis with special reference to the Mediterranean area.

In the Mediterranean area 2 subspecies of Echinococcus granulosus exist: E. g. equinus and E. g. granulosus. The latter is divided into sheep, cattle, pig and camel strains, the adult forms of which mainly occur in farm-dogs but sometimes in wild canidae. Some of these strains can infect man: namely, the sheep and the pig strain. The infectivity of the cattle strains for man is not certain. The epidemiological cycle is mainly a rural one, but it can become sylvatic or even urban. Thus, the epidemiological features of hydatidosis in the Mediterranean area are not basically different from the general epidemiology of the disease. But extensive rearing of sheep, combined with the carelessness and ignorance of people and with some particular habits, favours the maintenance of the infection.     

Symbiotic associations among the microplankton in oligotrophic marine environments, with special reference to the Gulf of Aqaba, Red Sea

Instances of symbiotic consortia in the microplankton of highlyoligotrophic seas are discussed on the basis of case studiesand long-term observations off the Israeli coast of the Gulfof Aqaba, Red Sea, and the inshore and offshore waters of theEastern Mediterranean. Associations described include diatomswith filamentous cyanophytes, diatoms with protozoans, tintinnidswith attached or encrusted diatoms, and acantharians with algalendosymbionts. Noted among the case studies is the frequentoccurrence of the endosymbiont cyanophyte Richelia inrracellularis,capable of molecular nitrogen fixation, in diatoms, includingthree species of Hemiaulus. For one of these associations, seeminglywith Hemiaulus sinensis, this is the first photographic record.The consortia are considered in relation to their seasonal distributionin depth profiles from the northern end of the Gulf of Aqaba,and in relation to their occurrence in the Eastern Mediterraneanand also worldwide in similar environments. These aspects andthe easily identifiable symbiotic nature of the consortia describedherewith make them useful as indicator species of warm wateroligotrophic seas.     

Chemical criteria for marine eutrophication with special reference to the Oslofjord,Norway

Results of a chemical and geochemical study of the Oslofjord system are presented to explore the possibility of qualitatively identifying a eutrophication gradient. Nutrient concentration and dissolved oxygen may indicate such a gradient in areas of similar hydrographies. Uncertainties due to minor differences in hydrography may be resolved by considering sedimentary organic carbon, C:N ratios and the accumulation of mineralisation products in the sediment pore water. The reliability of the sedimentary organic matter and the pore water composition as gradient indicators can be impaired by input of terrestrial organics, dispersal of mineralisation products by the benthic fauna or the apparent high levels of organic carbon and pore water nutrients in the absence of the benthic fauna under anoxic conditions.     

Advancing marine conservation planning in the Mediterranean Sea

Twenty leading scientists in the field of marine conservation planning attended the first international workshop on conservation planning in the Mediterranean Sea. This globally significant biodiversity hotspot has been subjected to human exploitation and degradation for 1,000s of years. Recently, several initiatives have tried to identify priority areas for conservation across the Mediterranean Sea. However, none of these efforts have led to large-scale actions yet. The aim of the workshop was to establish a network of scientists who are involved in large-scale conservation planning initiatives throughout the Mediterranean basin to promote collaboration and reduce redundancy in conservation initiatives. The three focus groups of the workshop build on existing efforts and intend to deliver: (1) a roadmap for setting conservation priorities, (2) a methodological framework for linking threats, actions and costs to improve the prioritization process, and (3) a systematic conservation planning process tailored to complex environments such as the Mediterranean Sea. Joining forces and involving more scientists (especially from the South-eastern part of the region) in following meetings, the participants endeavour to provide guidelines on how to bridge the science-policy gap and hence aid decision-makers to take efficient conservation actions.     

Wood-inhabiting marine fungi from San Juan Island, with special reference to ascospore appendages

Forty-four species were found on driftwood–two Basidiomycotina, six Deuteromycotina and 36 Ascomycotina. The most common species were Haligena elaterophora, Herpotrichiella ciliomaris, Remispora maritima, Halosphaeria appendiculata and Ceriosporopsis halima. Three species not previously illustrated are discussed. Ten new records for Washington State, U.S.A. are listed in Table 1. SEM observations on spore appendages in Banhegyia, Ceriosporopsis, Haligena, Herpotrichiella, Lulworthia, Remispora and Torpedospora are given.     

New records of marine Tardigrada in the Mediterranean Sea

Meiofauna from Chafarinas archipelago (western Mediterranean, N. Africa) were studied, and marine Tardigrada were identified to species level. A total of 15 species, belonging to families Stygarctidae, Halechiniscidac (Subfamilies Halechiniscinae, Florarctinae, Styraconyxinae and Tanarctinae), Batillipedidae, and Echiniscoididae, were found for the first time from the Alboran Sea and southwestern Mediterranean area. Four species and one subspecies are new records for the Mediterranean Sea: I'ioractus acer, F. asper, P. stellatus, Actinarctus doryphorus and Echiniscoides sigismundi hispaniensis. The male of Floractus stellatus , previously unknown to science, is described. Many species have been recorded for the first time in different sedimentary environments, such as midlittoral pools, very shallow gravels, pools in a mixed rocky environment or between Posidonia oceanica meadows, 'Amphioxus' gravels, and coastal detritic.     

Food digestibility of an Eurasian badgerMeles meles with special reference to the Mediterranean region

Feeding trials were carried out with a captive adult badgerMeles meles (Linnaeus, 1758) to establish relationships (digestibility coefficients) between the biomass of freshly consumed food and the dry undigested remnants recovered from scats (bone, teeth, hair, feathers, exoskeleton parts, seeds, etc). The foods studied were those revealed by our research to be the principal components of badger diet in a Mediterranean environment, and the values of the digestibility coefficients (DC) were: 24.74 for rabbitsOryctolagus cuniculus, 21.72 for rodents, 19.81 for pigeonsColumba sp., 99.50 for amphibians, 32.35 for arthropods imago, 44.39 for insect larvae, 18.45 for earthwormsLumbricus rubellus, 2.75 for acornsQuercus sp., 9.19 for arbutusArbutus unedo, 12.25 for blackberriesRubus ulmifolius, 46.12 for figsFicus carica, 34.87 for loquatsEriobotrya japonica, 10.94 for olivesOlea europaea, and 12.02 for pearsPyrus bourgaeana. The variability of DC values was measured, and attributed to the heterogeneity of constituents of the selected food types. There was no statistically significant correlation between the average weight of consumed food and the digestibility coefficients, confirming the expectation that such coefficients must be derived empirically for each food type.

     

Physico-chemical environment in Tjeukemeer with special reference to speciation of algal nutrients

This paper attempts to generalize the major controlling factors and their impacts on the physico-chemical environment in Tjeukemeer in relation to the speciation of algal nutrients.Morphometry, man-made hydrology, climate, chemistry of drainage area and biology of the lake appear to control its physico-chemistry the most. Thus the shallow Tieukemeer is vulnerable to wind and therefore almost always completely mixed and often turbid owing to resuspended sediments. In normal summers the lake is oligohaline, hard, eutrophic and alkaline, and in winter it is hard, eutrophic, alkaline and humus-rich. The implications of these properties on the following physico-chemical components and their relevance for the speciation of algal nutrients are discussed: turbidity, colour, halinity, pH, alkalinity, salinity, conductivity, ionic composition, ionic balance and organic matter.Because of the relationships between the physico-chemical environment on the one hand and the speciation and bio-availability of nutrients on the other hand, special attention is given to the speciation of some major and minor elements as derived from ultra filtration experiments. In this context, the metal binding capacity of the organic matter (mainly fulvic acids) is also considered.     

Biomass,production and activity of bacteria in the Black Sea,with special reference to chemosynthesis and the sulfur cycle

Abundance, morphological composition, vertical distribution, production and activity of total bacterioplankton and its specific groups in the Black Sea were investigated in August–September 1989. The total bacterioplankton was highest in the upper mixed layer (0.7–1 × 10⁶ cells ml^–1), corresponding to that in mesotrophic basins. In the N-E shallow part of the sea it attained 3 × 10⁶. Below the thermocline (50–100 m) the total number of bacteria decreased to 0.2–0.4 × 10⁶ ml^–1. In the redox gradient zone (zone of O₂-H₂S interface), it increased again. In deep anoxic waters the bacterioplankton, numbering 0.15–0.2 × 10⁶ ml^–1, was functionally inactive. Its biomass was 12–40 mg C m^–3 in the upper mixed layer, 5–10 mg C m^–3 in the intermediate cold layer (40–100 m depth), and 10–20 mg C^–3 in the redox zone. Maximum production rates occurred in the upper mixed layer (8–20 mg C^–3 d^–1) and in the redox-zone, 80–90% of it was due to chemosynthesis of thiobacilli. Below 200 m, microbial production decreased to about zero in the anoxic zone. Maximum activity of heterotrophic bacteria was recorded in the upper mixed layer, while thiobacilli and methaneoxidezing bacteria were most active in the redox-zone. Here, the maximum rates of H₂S and of thiosulfate oxidation, as well as maximum sulfate reduction were recorded. Chemical oxidation of H₂S was dominant. These results are discussed with respect to the present ecological situation of the Black Sea.     

Lytic and inhibition responses to bacteriophages among marine bacteria,with special reference to the origin of phage-host systems

The results of phage-host cross-reaction tests reported by Moebus & Nattkemper (1981) were re-examined using serially diluted bacteriophage suspensions to elicit the actual type of reaction between the bacteria and phage lysates tested. More than 1450 phage-host systems were studied at 25 °C incubation temperature. Among the nearly 300 phage strains used, 29 were identified as temperate ones. In about 65 % of the phage-host systems bacteriophage propagation was indicated by plaque formation. The remaining systems were characterized by the inhibition reaction of bacteria to phage lysates indicated by homogenously reduced bacterial growth within the test area without production of progeny phages. Since crude phage lysates had to be used, it remains obscure whether agents other than infective phage particles (defective ones or bacteriocins) caused this reaction. Among 269 systems of the inhibition type which were also tested at 5° and 15 °C, 54 were observed to propagate phages at one of or both the lower temperatures. Plaques produced at 15 °C with several phage-host systems were found to yield only few progeny phages which generally could not be propagated to produce high-titer phage stocks. With one system temperature-sensitive phage mutants were isolated. The probability of inhibition reactions occurring was found to be higher with phage-host systems isolated east of the Azores than with systems derived from the western Atlantic. With systems from the last mentioned area the proportion of inhibition versus lytic responses of bacteria to phages was observed to increase with the distance between the stations where both parts of the systems were derived. The latter findings are discussed in view of the assumption that bacterial and bacteriophage populations undergo genetic changes while being transported from west to east.     

Eggs of pelagic fish from the Sargasso Sea with special reference to Anguilliformes

Pelagic fish eggs from IKMT hauls, taken during the 1979 Sargasso Sea Expedition, were sorted and classified according to structural aspects. 13 types were distinguished, one of them classified as exocoetid, two of them as anguilliform. One of the anguilliform egg types could be determined as belonging toDerichthys serpentinus.     

Detection of Arcobacter spp. in the coastal environment of the Mediterranean Sea

The occurrence of Arcobacter spp. was studied in seawater and plankton samples collected from the Straits of Messina, Italy, during an annual period of observation by using cultural and molecular techniques. A PCR assay with three pairs of primers targeting the 16S and 23S rRNA genes was used for detection and identification of Arcobacter butzleri, Arcobacter cryaerophilus, and Arcobacter skirrowii in cultures and environmental samples. Only one of the Arcobacter species, A. butzleri, was isolated from seawater and plankton samples. With some samples the A. butzleri PCR assay gave amplified products when cultures were negative. A. cryaerophilus and A. skirrowii were never detected by culture on selective agar plates; they were detected only by PCR performed directly with environmental samples. Collectively, our data suggest that culturable and nonculturable forms of Arcobacter are present in marine environments. The assay was useful for detecting Arcobacter spp. both as free forms and intimately associated with plankton. This is the first report showing both direct isolation of A. butzleri and the presence of nonculturable Arcobacter spp. in the coastal environment of the Mediterranean Sea.     

An evaluation of the mutagenic, carcinogenic and teratogenic potential of microwaves

A notable proportion of the population is exposed to an increasing number of devices emitting microwaves, a form of non-ionizing electromagnetic radiation in the range 300-30000 mHz. The activation energy of microwave radiations is too small to directly modify any chemical bonds in the irradiated matter. At microwave frequencies the macroscopic dielectric properties of tissues are strongly determined by their water content. Tissues like muscle, brain, skin, with a high water content, have higher permittivity and conductivity values than bone or fat with low water contents. Owing to the energy transfer, to living tissues, by a dipolar relaxation mechanism of water molecules, the penetration of microwaves is limited and one observes a fast and very efficient heat-loss production. A review of the available literature shows that most results on the mutagenicity of microwaves are negative or can often be explained by a temperature enhancement. If microwaves are apparently unable to damage DNA at sub-thermal exposure levels, some results indicate, however, that they might easily potentiate the damaging action of other DNA antagonist agents such as UV or chemicals.