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1.
The coral reefs of the Gulf of Aqaba are among the most northern ones of the world. This study, the first concerning the east coast of this topographically and hydrographically peculiar sea, considers relationships of biophysiographical and structural reef zones to fundamental abiotic environmental factors. An introduction to paleogeography, geology, petrography, topography, climate and hydrography is followed by terminological definitions used to describe the different reef areas. The investigations were carried out on two transects crossing fringing reefs of different shape. Each transect was 20 m wide and run from the shore over nearly 200 m to the fore reef in about 30 m depth. One reef, a “coastal-fringing reef”, represents an unaltered straight reef flat from shore to the reef edge 60 m away; two large pinnacles reach the surface some 125 m off the shore. The other reef, a “lagoon-fringing reef”, is divided into a 100 m wide lagoon of 0.5–2.3 m depth and a reef crest separated from the former by a rear reef. The reef platform of the lagoon-fringing reef is cut by a system of channels and tunnels; the reef edge is about 135 m off shore. Such water depth, substrate, temperature, illumination and water movement were recorded, about 200 common or dominant species (plants and animals) were collected, their distribution plotted and, together with other data and structural items, charted. Indicator species characterize the biophysiographical zones. Their variation as well as that of the structural and substrate zones depend on different zones of water movement. This basic factor also controls other ecological parameters such as food and oxygen supply as well as temperature and salinity gradients between fore reef and shore. From this point of view the ecological requirements of some indicator and other species and conversely the ecological settings of different reef areas are discussed. The different shapes of both reefs are explained on the basis of a “reef development cycle” — a hypothesis applicable to fringing reefs at unchanging sea level and based on the fact that only a small surf-influenced area of “living reef” is able to compensate for reef destruction: While a young coastal fringing reef is growing outwards, its back reef is gradually altered to a reef lagoon by erosion. After stillstand of seaward expansion the reef crest, too, is cut by a channel system eroded by rip currents. This stage is represented by the lagoon-fringing reef. Isolated pinnacles remain as remnants of the former reef crest; young coastal-fringing reefs develop from the shore. This stage is examplified by the first reef studied. Extension, growth intensity, dominant frame building corals, and the number of species of the Aqaba reefs are compared with those of Eilat and with reefs of the middle Red Sea, South India, Southwest-Pacific and Jamaica.  相似文献   

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Ohne ZusammenfassungHerrn Prof. Dr. Ferdinand Pax zum 75. Geburtstag gewidmet.  相似文献   

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The cricetids are one of the dominating groups of the rodent fauna of Maramena. Among the three described cricetids:Kowalskia browni n. sp.,Allocricetus cf.ehiki andHypsocricetus strimonis n. g. n. sp. two are new.K. browni represents a stage of evolution betweenK. skofleki andK. magna. This gives support to the supposed stratigraphie position (Late Turolian, MN 13) of the Maramena fauna.  相似文献   

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Following previous investigations on a fringing reef in the Red Sea near Aqaba (Mergner & Schuhmacher, 1974; Mergner & Svoboda, 1977) this paper presents a quantitative analysis of the faunal and floral stock in one of the selected test areas (5×5 m) located in the reef lagoon studied. During the observation period 237 macrobenthic species of 192 genera were found. Species numbers were 22 (algae), 18 (cnidarians), 22 (crustaceans), 113 (molluscs), 27 (echinoderms), 14 (fishes) and 21 (smaller animal taxa including foraminiferans, sponges, turbellarians, polychetes and ascidians). These numbers, though derived from a small and relatively monotonous reef area, exceed by far all data known from comparable reef zones. The ecological conditions as well as habitat preferences, times of occurrence, seasonal abundances, species diversities and dominances of the inhabitants observed in the test area are discussed. Comparisons of the population data of October, 1975 and March, 1976 indicate the influence of the succession, abundance and disappearance of the phytal on the environmental conditions of the mobile fauna, for example molluscs, echinoderms and fishes. The increase of some of its species, especially of juvenile individuals, is remarkable. Within the same period juvenile colonies of some xeniids and the stony coralStylophora pistillata undergo similar seasonal fluctuations; colonies eliminated by grazers or other, unknown circumstances, are replaced by new settlers. Altogether, the faunal and algal stock of this lagoon area can be interpreted as a climax community; its impressive density is apparently the result of a high number of various microhabitats. Each of these ecological niches provides manyfold living spaces for specific communities with different adaptive strategies. The highest number of species plus the highest diversity indices rank mostly among the mobile groups.

Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   

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Quantitative studies of coral communities in the central and northern Red Sea were designed for comparison of the community structure in both areas. The central Red Sea provides reef-building Scleractinia and reef-inhabiting Alcyonaria with optimal temperature conditions, whereas the north tip of the Gulf of Aqaba (29°30 N) represents the northernmost outpost of coral reefs in the Indian Ocean. It is generally assumed that coral diversity decreases towards the margins of the global reef-belt. In the Red Sea, generic diversity of hermatypic Scleractinia slightly decreases from the central to the northern part (51 : 48 genera); but cnidarian species abundance (species number per 25 m2 area) was found to increase from 62 to 98 species and the Shannon-Wiener diversity index increased from 2.58 to 3.67 with regard to colony number. The mean colony size was 189 cm2 at Sanganeb-Atoll, but only 52 cm2 at Aqaba. The mean numbers of colonies were inversely related: 662 per 25 m2 at Sanganeb-Atoll and 2028 at Aqaba. Uninhabited parts of the studied areas amounted to 47 % at Sanganeb-Atoll and to 56 % at Aqaba. The community structure of the studied areas indicates that occasional perturbations prevent the progress of the community towards a low-diversity equilibrium state. Since severe hydrodynamic damage is extremely rare in 10 m depth, major disturbances may occur by sedimentation, by the interference of grazers (e. g.Diadema setosum) and due to overgrowth by space-competitors (mainly soft corals). These events are to be regarded as throwbacks in the process of monopolization of the area by well adapted species. Recovery from such perturbations (i.e. recolonization of dead areas) obviously takes place at different velocities in the northern and central Red Sea, for the mean water temperature at Aqaba is 5 °C lower than in the central Red Sea. Hence the process of taking over a given space by a few species proceeds further in the central Red Sea than at its northern end. The increase in diversity per area towards high latitudes is comparable to that with depth. It is concluded from the great number of species at Aqaba that these reefs mark the northernmost outpost of the Indian Ocean only geographically but not ecophysiologically; they would occur at even higher latitudes, if the Gulf of Aqaba extended farther north.  相似文献   

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Summary The uptake of labelled phosphate, especially the incorporation in the organic, in TCA soluble phosphate compounds of the unicellular green alga Ankistrodesmus braunii is markedly stimulated by Na+ more in the light but is stimulated in the dark as well (Na+-effect). This stimulation depends on the phosphate concentration and on the sodium concentration of the medium (optimum 10-3M NaCl) and appears in short-time incorporations (1 min) only at low phosphate concentrations (10-7 to 10-5 m PO4). In addition the Na+-effect depends on temperature and almost disappears at 1°C. The incorporation of 32P in the dark is strongly inhibited by 2,4-dinitrophenol (DNP) and under this condition only a very samll increase of the 32P incorporation by Na+ can be measured. In the light however the same concentration of DNP has only a low effect on 32P incorporation in case no Na+ is present in the medium. If Na+ is present in the medium, the effect of DNP on 32P incorporation is increased in the light. The Na+-effect in the light is also inhibited by di-chlorophenyl-1,1-dimethylurea (DCMU) in N2-atmosphere. High concentrations of g-Strophantin (10-3 m) inhibit the uptake of phosphate by Ankistrodesmus; the inhibition is more increased in the presence of KCl than in the presence of NaCl. The results clearly indicate, that Na+ will not effect the incorporation of labelled phosphate by means of influencing passive processes of phosphate diffusion or phosphate exchange, but acts on different energy-requiring processes of phosphorylation in dark and light. At present one could conclude, that Na+ acts less through a mechanism of a sodium pump, but rather affects the formation of energy-rich compounds (in the dark by way of the oxydative phosphorylation, in the light perhaps by means of the non-cyclic photosynthetic phosphorylation).  相似文献   

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Two new isolated upper anterior premolars (p1–3) of multituberculates are described from the Barremian of Galve in Spain. One specimen is tricuspid and belongs toEobaatar hispanicus Hahn &Hahn, 1992. The other is the first tetracuspid p1–3 known from Galve. It is very similar to respective teeth of the Paulchoffatiidae G.Hahn, 1969 from the Upper Jurassic of Portugal. Therefore, this very small tooth belongs very probably to the paulchoffatiid taxonGalveodon nannothus Hahn &Hahn, 1992 which is also characterized by tiny dimensions  相似文献   

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Zusammenfassung 1. Die Veränderungen des Meeres, die durch das Einbringen von Abfällen ins Meer hervorgerufen werden können, werden besprochen.2. Vier verschiedene Arten von Veränderungen werden unterschieden: (a) Veränderungen am Meeresboden, (b) Veränderungen im Meerwasser, (c) Veränderungen an der Meeresoberfläche, (d) Veränderungen in der Luft über dem Meer.3. Als Maß für die Schädlichkeit schwer löslicher Abfälle, die auf den Meeresboden absinken, wird die von den Abfällen zugedeckte Fläche am Meeresboden benutzt.4. Als Maß für die Schädlichkeit von Abfällen im Meerwasser wird das schädlich veränderte Meerwasservolumen eingeführt. Das schädlich veränderte Meerwasservolumen ist dasjenige Volumen, in dem durch das Einbringen von Abfällen Schäden auftreten können, weil ein bestimmter Grenzwert, beispielsweise eine Grenztemperatur oder eine Grenzkonzentration (z. B. die Erträglichkeitsgrenze), über- oder unterschritten ist. Bei kontinuierlichem Einbringen von Abfällen ist der zeitlich konstante Wert, bei ein- oder mehrmaligem Einbringen der zeitliche Maximalwert des schädlich veränderten Meerwasservolumens ausschlaggebend. Für Überschlagsrechnungen kann man den zeitlichen Maximalwert des schädlich veränderten Meerwasservolumens demjenigen Meerwasservolumen gleichsetzen, das erforderlich ist, um den betreffenden Abfall bis zur Ungefährlichkeit und Unschädlichkeit zu verdünnen.5. Als oberstes Gebot für das Einbringen von Abfällen ins Meer wird die Notwendigkeit herausgestellt, die negativen Wirkungen der Abfälle auf Pflanzen und Tiere des Meeres und der Küstenländer, auf Schiffahrt, Fischerei, Sport und Tourismus und nicht zuletzt auf die Gesundheit des Menschen so klein wie möglich zu halten.6. Unter Berücksichtigung dieses Gebotes wird eine Klassifizierung von Abfällen und Meeresgebieten vorgeschlagen.7. Die vorgeschlagene Klassifizierung teilt die Abfälle unter Berücksichtigung von Stoff und Menge in fünf Gefahrenklassen ein und gibt an, ob und bei welchen Wassertiefen die Abfälle ins Meer eingebracht werden dürfen.8. Für die Einordnung von Abfällen in die einzelnen Gefahrenklassen werden Kriterien angegeben. Diese Kriterien berücksichtigen Art, Ausmaß und Dauer der durch die Abfälle im Meer hervorgerufenen Veränderungen.9. Die Kriterien für die Einordnung von Abfällen in die einzelnen Gefahrenklassen und die Angaben darüber, ob und bei welchen Wassertiefen die Abfälle ins Meer eingebracht werden dürfen, sind in Form einer Tabelle zusammengestellt.10. An Hand von praktischen Beispielen wird die vorgeschlagene Klassifizierung erläutert.
Changes of the sea by wastes, and the introduction of five danger classes for the disposal of wastes in the sea, based on such changes
There are four different kinds of changes caused by the disposal of wastes into the sea: changes on the sea floor, in the seawater, at the surface and in the air above the sea. The measure for the harmful effect of insoluble wastes on the sea floor is the area covered by the wastes. The measure for harmful effects in sea-water is the water volume with harmful properties; this is the volume in which a certain critical value (temperature, concentration, etc., e. g. in regard to the tolerance limits of organisms) is surpassed. In case of continuous waste disposal, the constant value (with time) of the water volume with harmful properties is decisive; in case of a singular or repeated disposal, the maximum value (with time). The maximum value of the water volume with harmful properties is almost equal to the water volume necessary for making a waste harmless by dilution. It is necessary to keep negative effects of wastes on organisms, fisheries, sport and tourism, and — last but not least — on the health of mankind, as small as possible. Keeping this necessity in mind, a classification of wastes and sea areas is proposed. This classification divides the wastes, according to substance and quantity, into five classes and provides information whether or not wastes may be disposed of in the sea and at which depths. Special criteria are provided for the classification of waste products; these criteria take into consideration type, extent, and duration of the changes caused in the sea. Examples are given to demonstrate the application of the proposed classification in praxis. Criteria for waste classification and instructions for disposal in sea areas of different depths are given in a table.
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A structurally preserved specimen of a freshwater sponge (Spongillidae, gen. et sp. indet.) is described from finely laminated, siliceous-clayey lake sediments of late Oligocene age of the locality Rott (Siebengebirge near Bonn, Germany). The preservation is caused by an early stabilization of the needle skeleton by phosphate minerals. The phosphate replaced the soft parts of the sponge body in its shape (without however preserving cellular details) and figures the original structure of the body with central cavity (spongocoel), canals and possibly flagellate chambers.  相似文献   

13.
Zusammenfassung Im ersten Teil der Arbeit wird als Ursache für die Zunahme der RBW schneller Elektronen mit ihrer Eindringtiefe die Änderung ihres Energiespektrums vorausgesetzt. Über die Ermittlung der Quelldichte der Sekundärelektronen wird, unter Einbeziehung der Primärelektronen, die energieabhängige Elektronenflußdichte für zwei verschiedene Primärelektronen-Energien berechnet. Im Verein mit den auf anderem Wege erhaltenen ähnlichen Resultaten vonHarder wird ein wahrscheinlicher Verlauf der energieabhängigen Elektronenflußdichte für zwei verschiedene Tiefen ermittelt.Im zweiten Teil wird zur Berechnung der RBW die strahlenbiologische Wirkung proportional zum Produkt aus der Elektronenflußdichte und einer der physikalischen Wechselwirkung mit dem biologischen Modell entsprechenden spektralen Empfindlichkeitsfunktion angesetzt. Die Anwendung der im ersten Teil ermittelten Spektralfunktion auf dieses Prinzip liefert für den Fall der Übertragung von Ionisations- und Anregungsenergie auf den Zellkern durch-Elektronen nur für Energien zwischen 5 und 10 keV die richtige Tiefenabhängigkeit der RBW. Dasselbe gilt für die Übertragung von Ionisationsenergie auf den Zellkern durch K-Schalen-Ionisation biologisch wichtiger Elemente mit anschließendem Auger-Effekt (SchrapnellWirkung). Dagegen erhält man bei Annahme der Energieübertragung durch Plasmonanregung oder Einzelionisationen keine den Experimenten entsprechende Zunahme der RBW mit der Tiefe.Herrn Prof. Dr. med. H.-St.Stender, Herrn Priv.-Doz. Dr. B.Markus und Herrn Priv.-Doz. Dr. D.Harder danke ich für wertvolle kritische Anmerkungen und anregende Diskussionen zum vorliegenden zweiten Teil der Arbeit.  相似文献   

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Zusammenfassung Die mit Hilfe neuer dünnschichtchromatographischer Methoden (Hager u. Meyer-Bertenrath, 1966) getrennten Carotinoide aus Blättern (Avena, Spinacia, Veratrum, Elodea, Potamogeton) und anderen Organen höherer Pflanzen (Solanum, Taxus, Daucus) sowie aus Chlorella und Euglena wurden neu bestimmt und identifiziert.Zur Bestimmung wurden folgende Kriterien herangezogen: Die Absorptionsmaxima in den verschiedenen Lösungsmitteln Hexan, Benzol, Chloroform, Äthanol, Schwefelkohlenstoff; der Kurvenverlauf in diesen Lösungsmitteln und die Form des kurzwelligen Maximums als Charakteristikum für die - oder -Jononstruktur; Co-Chromatographie mit synthetischen oder selbst isolierten Carotinoiden; jodinduzierte cistrans-Umlagerungen und Herstellung stereoisomerer Formen; säurekatalytische Umwandlung von Epoxiden in die furanoiden Formen und Messung der hypsochromen Verschiebung der Absorptionsmaxima; Reduktion von Farbstoffen mit Ketogruppen zu Hydroxyverbindungen; Messung der verschieden schnellen Bildung von Mono- oder Diäthern an allyl- bzw. nicht-allylständigen Hydroxygruppen.Folgende Farbstoffe wurden bestimmt und ihre relative Lage an den beiden verwendeten verteilungs- und adsorptionschromatographischen Verfahren aufgezeigt: -Carotin, -Carotin, -Carotin, -Carotin, Lycopin, -Carotin-5,6-Epoxid, -Cryptoxanthin, Lutein-5,6-Epoxid, Violaxanthin, Lutein, Antheraxanthin, Neoxanthin, Neoxanthin Neo A, Zeaxanthin, Rhodoxanthin.Die Abweichungen der neu gemessenen Absorptionsmaxima von den in der Literatur angegebenen teilweise fehlerhafte Zahlenwerten sind aus Tabellen ersichtlich.
The identification of carotenoids from leaves and algae separated by thin-layer chromatography
Summary Carotenoids from leaves (Avena, Spinacia, Veratrum, Elodea, Potamogeton) and other tissues of higher plants (Solanum, Taxus, Daucus) and from Chlorella and Euglena were identified and characterized employing new methods in thin-layer chromatography (Hager and Meyer-Bertenrath, 1966).The following criteria were used for the identification procedure:1.The absorption maxima in different solvents such as hexane, benzene, chloroform, ethanol, and carbon disulphide. 2. The absorption spectra in these solvents and the shape of the short wave maximum, which is characteristic for the - or -ionone structure. 3. Co-chromatography with synthetic or isolated carotenoids. 4. Iodine induced cis-trans isomerizations and the formation of stereoisomers. 5. The acid catalyzed conversion of epoxides into the isomeric furanoid oxides and the measurement of hypsochromic shift of the absorption maxima. 6. Reduction of keto group containing pigments to the hydroxy compounds. 7. Determination of the different formation velocity of mono- or diethers of hydroxy groups in the allyl or non-allyl position.THe following pigments were characterized and their relative position on partition and adsorption thin-layer chromatograms was determined: -carotene, -carotion -carotene, -carotene, lycopene, -carotene-5,6-epoxide, -cryptoxanthin, lutein-5,6-epoxide, violaxanthin, lutein, antheraxanthin, neoxanthin, neoxanthin Neo A, zeaxanthin, rhodoxanthin.Deviations of the newly determined absorption maxima from the data cited in the literature, part of which is erroneous, can be learned from tables.
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17.
Zusammenfassung Es werden dünnschichtchromatographische Methoden zur schnellen quantitativen Bestimmung der Chlorophylle und Carotinoide angegeben. Als Beispiel für verschiedenes pflanzliches Ausgangsmaterial wird die Extraktion der Farbstoffe aus Algen, Blättern oder Chloroplasten genauer beschrieben.Aus diesen Extrakten erfolgt die Auftrennung der Carotinoide nach einem adsorptionschromatographischen Verfahren; die Dünnschicht ist hierbei aus anorganischen Adsorbentien (CaCO3, MgO, Ca(OH)2) zusammengesetzt. Die Basizität der Schicht wird durch Zugabe von KOH weiter verstärkt; dadurch gelingt es, die Chlorophylle am Auftragungsort zurückzuhalten, so daß die sonst auftretenden störenden Überlagerungen von Chlorophyllen und Xanthophyllen im Chromatogramm einwandfrei vermieden werden können. Mit dieser Methode lassen sich auch, solche Carotinoide separieren, welche sich nur in der Lage einer Doppelbindung unterscheiden, wie z. B. - und -Carotin oder Lutein und Zeaxanthin. In einem einzigen Chromatogramm ist deshalb die Trennung aller wesentlichen Carotinoide möglich, aus einem Chlorella-Extrakt z. B. (mit fallendem Rf-Wert): -Carotin, Lutein-5,6-Epoxyd (Spuren), Violaxanthin, Lutein, Antheraxanthin, Neoxanthin Neo A, Neoxanthin und Zeaxanthin. Ferner wird das chromatographische Verhalten der nicht allgemein vorkommenden Carotinoide -Carotin, -Carotin, Lycopin und Rhodoxanthin beschrieben.Die Chlorophylle a und b werden aus dem Gesamtextrakt auf einer zweiten Dünnschicht nach einem verteilungschromatographischen Verfahren getrennt; diese Schicht besteht aus Kieselgel, dem Ascorbinsäure als Oxidationsschutz beigemischt wird. Eine Apparatur zur gleichmäßigen, strichförmigen Auftragung definierter Extraktmengen und Vorrichtungen zur schnellen quantitativen Eluierung der Farbstoffe aus dem Adsorbens werden beschrieben.Die für die Berechnung der Farbstoffmengen noch fehlenden spezifischen Extinktionskoeffizienten E 1 cm 1 % für Antheraxanthin in Äthanol und -Carotin in Chloroform wurden ermittelt.
Extraction and quantitative determination of carotenoids and chlorophylls of leaves, algae and isolated chloroplasts with the aid of thin-layer chromatography
Summary Methods for a rapid quantitative determination of chlorophylls and carotenoids are decribed.The extraction of pigments was carried out with different kinds of plant material, such as algae, leaves and chloroplasts. The separation of the carotenoids from these extracts was succeeded by an adsorptionchromatographic process in which the thin-layer consists of anorganic adsorbents (CaCO3, MgO, Ca(OH)2). The basicity of the layer is further increased by the addition of KOH; thereby the chlorophylls are retained at the starting line and the overlapping of chlorophylls and xanthophylls on the chromatogram can be avoided.With this method even those carotenoids can be separated which differ only in the position of a double bond, as for instance - and -carotene, and lutein and zeaxanthin. Thus the separation of all the principal carotenoids on a single chromatogram is possible, for example from a Chlorella extract (in order of decreasing Rf-value): -carotene, -carotene, lutein-5,6-epoxide (traces), violaxathin, lutein, antheraxanthin, neoxanthin neo A, neoxanthin and zeaxanthin. Furthermore the chromatographic behaviour of the carotenoids -carotene, -carotene, lycopene and rhodoxanthin, which are found only rarely, is described.The chlorophylls a and b are separated by a partition chromatographic process on the second thin-layer; this layer consists of silica gel mixed with ascorbic acid as an antioxidant. An apparatus for an equal spreading of defined quantities of the extract on the starting line and new methods for a rapid quantitative elution of the pigments from the adsorbent are described.The specific extinction coefficients E 1 cm 1 % for antheraxanthin in ethanol and for -carotene in chloroform, which were needed for the calculation of the pigment quantity were determined.
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