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Berpolarforsch2000370.Pdf Struktureigenschaften und Nahrungsbedarf der Zoobenthosgemeinschaften im Bereich des Lomonossowrückenim Arktischen Ozean Structures and nutrition requirements of macrozoobenthic communities in the area of the Lomonossov Ridge in the Arctic Ocean Hendrik Deubel Ber. Polarforsch. 370 (2000) ISSN 0176 - 5027 Hendrik Deubel Alfred-Wegener-Institut füPolar- und Meeresforschung Postfach 12 01 61 Columbusstrasse D - 27568 Bremerhaven Diese Arbeit ist eine leicht verändert Fassung einer Dissertation, die in der Sektion Biologie l bei Prof. Dr. W. Arntz angefertigt und im Juli 1999 dem Fachbereich 2 (BiologieIChemie) der UniversitäBremen vorlegt wurde. Inhaltsverzeichnis Seite Zusammenfassung 1 . Einleitung .................................................................................................... 2 ..Untersuchungsgebiet ............................................................................ 2.1 Arktischer Ozean ................................................................................... 2.1 .1 Geographie des Arktischen Ozeans ............................................. 2.1.2 Hydrographie des Arktischen Ozeans .......................................... 2.1.3 Meereis des Arktischen Ozeans .................................................. 2.2 Laptewsee und Lomonossowrucken.................................................... 2.2.1 Geographie der Laptewsee ........................................................ 2.2.2 Hydrographie der Laptewsee ....................................................... 2.2.3 Meereis in der Laptewsee ........................................................... 2.2.4 Lomonossowrücke................................................................... 3 . Material und Methoden .......................................................................... 3.1 Probennahme......................................................................................... 3.2 Art- und Gewichtsbestimmung ............................................................. 3.3 Gemeinschaftsanalyse .......................................................................... 3.4 Strukturelle Merkmale ........................................................................... 3.4.1 Berechnung von Diversitäund Dominanz ................................... 3.4.2 Berechnung des Biologischen Index ............................................ 3.4.3 Bestimmung von Charakterarten und Diskriminatoren .................. 3.4.4 Biologische Struktur .................................................................... 3.5 Korrelation von Umweltfaktoren mit dem biologischen Verteilungsmuster .................................................................................. 3.6 Bilanzierung des Nahrungsbedarfs ...................................................... 4 . Ergebnisse .................................................................................................. 4.1 Artenliste ................................................................................................ 4.2 Tiefenverteilung der taxonomischen Großgruppe............................. 4.2.1 Transekt A .................................................................................. 4.2.1 .1 Artenzahl ............................................................................ 4.2.1.2 Abundanz ........................................................................... 4.2.1.3 Biomasse ........................................................................... 4.2.2 Transekt B .................................................................................. 4.2.2.1 Artenzahl ............................................................................ 4.2.2.2 Abundanz ........................................................................... 4.2.2.3 Biomasse ........................................................................... 4.2.3 Transekt F ................................................................................... 4.2.3.1 Artenzahl ............................................................................ 4.2.3.2 Abundanz ........................................................................... 4.2.3.3 Biomasse ........................................................................... 4.2.4 Transekt Arctic Ocean'96 (= AO'96) ............................................ 4.2.4.1 Artenzahl ............................................................................ 4.2.4.2 Abundanz ........................................................................... 4.2.4.3 Biomasse ........................................................................... 4.3 Gemeinschaftsanalyse .......................................................................... 4.3.1 Clusteranalyse ............................................................................ 4.3.2 k-Dominanzkurven ...................................................................... 4.3.3 Diversitäte................................................................................. 4.3.4 Artenzusammensetzung der Stationsgruppen.............................. 4.3.4.1 SCHELF ............................................................................. 4.3.4.2 HANG ................................................................................ 4.3.4.3 RUCKEN ............................................................................ 4.3.4.4 RAND ................................................................................. 4.3.4.5 TIEF ................................................................................... 4.3.4.6 ZENTRAL-FLACH .............................................................. 4.3.4.7 ZENTRAL-TIEF .................................................................. 4.3.5 Diskriminatoren ........................................................................... 4.3.6 Relative Häufigkeiteder Großtax............................................. 4.3.6.1 Artenzahl ............................................................................ 4.3.6.2 Abundanz ........................................................................... 4.3.6.3 Biomasse ........................................................................... 4.3.7 Ernährungstype ......................................................................... 4.3.7.1 Artenzahl ............................................................................ 4.3.7.2 Abundanz ........................................................................... 4.3.8 Epi-Ilnfauna ................................................................................ 4.3.8.1 Artenzahl ............................................................................ 4.3.8.2 Abundanz ........................................................................... 4.4 Korrelation der biologischen Struktur mit den abiotischen Parametern (BIO-ENV-Analyse) ........................................ 4.5 Nahrungsbilanzierung ........................................................................... 5 . Diskussion ................................................................................................... 5.1 Zum Artenspektrum der Makrofauna am Lomonossowrücke............................................................................. 5.1 . 1 Charakterarten und Diskriminatoren ............................................ 5.1.2 Bedeutende Faunenelemente...................................................... 5.2 Zu Ökologische Aspekten am Lomonossowrücke........................... 5.2.1 Zonierung .................................................................................... 5.2.2 Ernährungstype......................................................................... 5.3 Zur Diversitat am Lomonossowrücke................................................. 5.4 Zur Nahrungsbilanzierung der Makrofauna am Lomonossowrücke. 5.4.1 Nahrungsbedari des Makrozoobenthos ....................................... 5.4.2 Benthische Größenklass.......................................................... 5.4.3 Sedimentation und Nahrungsverfügbarkei.................................. 5.5 Schlussbetrachtung .............................................................................. 6 . Literatur ......................................................................................................... 7. Anhang. .................... ........ .. .. .. ..... ..................... .... ............... .. 130 Danksagung... .. .. .. .. .. .. .. .. .. .. .. .. .. .. ... ... .. .. .. .. ... i47 - III - ZUSAMMENFASSUNG ZUSAMMENFASSUNG Die Makrozoobenthos-Gemeinschaften der nördliche Laptewsee sowie der permanent eisbedeckten Regionen der zentralen Arktis im Bereich des Lomonossowrücken werden beschrieben, und es wird eine Bilanzierung des Nahrungsbedarfs der Makrofauna auf Grundlage von Biomassedaten durchgeführt Die Probennahme erfolgte auf zwei "POLARSTERN" - Expeditionen in den Sommern 1995 und 1998 sowie einer Expedition mit dem schwedischen Eisbrecher "ODEN" (Arctic Ocean.96) in die Arktis, Die "POLARSTERN" - Fahrt ARK XI11 (07.07 - 20.09. 1995) führt auf den nördliche Schelf der Laptewsee, in den Bereich des südliche Lomonossowrückenund der angrenzenden Tiefseebecken bis 81' N. Der zentrale Bereich des Rückenund der Tiefseebecken zwischen 85' N und 89' N wurde auf der Expedition "Arctic Ocean'96" (12.07 - 28.09. 1996) beprobt. Diese Untersuchung wurde durch eine Probe vom Lomonossowrückeder Expedition ARK XIVII a (27.06 - 28.07. 1998) (= 83' N) ergänzt Insgesamt wurde die Evertebraten-Makrofauna aus 82 Großkastengreiferprobe (= Stationen), die
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