{"id":68,"date":"2018-07-12T21:56:31","date_gmt":"2018-07-12T19:56:31","guid":{"rendered":"http:\/\/www.oceanblogs.org\/pos525\/?p=68"},"modified":"2018-07-12T22:32:21","modified_gmt":"2018-07-12T20:32:21","slug":"on-board-experiments-bord-experimente","status":"publish","type":"post","link":"https:\/\/www.oceanblogs.org\/pos525\/2018\/07\/12\/on-board-experiments-bord-experimente\/","title":{"rendered":"On-board experiments – Bord-Experimente"},"content":{"rendered":"

[German translation below]<\/p>\n

On-board experiments<\/h3>\n

Thirteen days on-board and the experiments are running smoothly. All those wires and cable ties for what, you ask?<\/p>\n

Well, my main task on this vessel is to run respiration incubations. I have had help from Tina for a few days and now she has been replaced by the PhD student, \u00d8ystein, of our group at IMR. Basically, we do laboratory work, except that instead of being in a lab and sleeping at home, we work on a moving boat and we don\u2019t sleep much.<\/p>\n

\"\"

Sun is up – like me, at 4:15 AM. Picture: Narimane Dorey.<\/p><\/div>\n

\"\"

Our very tidy on-bard set-up made of fish tanks, cables, cable ties, and zip-block bags. Picture: Narimane Dorey.<\/p><\/div>\n

This has big advantages though: we get very fresh corals and seawater, directly from the ocean behind us and we don\u2019t have to transport and acclimatize our corals to lab conditions and can start experiments immediately in conditions that are closer to what happens in reality.<\/p>\n

The main question for us is to look at how our corals respond to stress. So, we put them in a water bath (a big tank where we can regulate temperature) and raise the temperature quite rapidly. We start at 5\u00b0C increase the temperature to 15\u00b0C by steps of 2 degrees every 12 hours. So far, we were quite surprised by the resistance of corals. They look still healthy at 15\u00b0, although they live at around 5-8\u00b0C in their reef habitats here in Norway.<\/p>\n

But this is just preliminary \u201cimpressions\u201d. We actually measure some numbers, too. We put the coral fragments in closed chambers and we measure oxygen decrease in the seawater of those chambers over time: the drop in oxygen in the chamber is a measure of the respiration of the coral pieces in the chamber that consume the oxygen while breathing. Today and until tomorrow we\u2019re working on corals from the third reef location we are aiming to analyse, with \u00d8ystein opening and closing the respiration chambers and me writing down notes.<\/p>\n

\"\"

Corals are in the chambers and pumps for water circulation are being connected. Picture: Narimane Dorey.<\/p><\/div>\n

What we should see is that respiration goes up with temperature \u201cstress\u201d. It is a bit similar with humans: respiration varies with different parameters: for example when you run, you need to increase your input of oxygen to be able to \u201cfeed\u201d your muscles with oxygen. Corals (and many other invertebrates) don\u2019t work exactly like humans, but their respiration increases when temperature increases. This is not new, but what we are particularly interested in is if corals from different reefs respond differently to stress.<\/p>\n

 <\/p>\n

For various reasons, we think that the coral reefs that are closer to the coastline of Norway will be more resistant to this temperature stress than the corals that are further away from the coast. This is our working hypothesis for this cruise and this experiment.<\/p>\n

\"\"

Oxygen decrease when we put the coral in the respiration chambers. Picture: Narimane Dorey.<\/p><\/div>\n

Now, to test this hypothesis, we do the experiment that I described above. We will look at respiration, but we also have other markers of stress that we will look at later in the lab when we are back in Bergen. We hope to see more respiration in the \u201cmore stressed\u201d fragile corals and we hope to see differences between different reefs. That would confirm our hypothesis. But, if our hypothesis is not confirmed, it will also be very interesting. This information is very important, especially looking at climate change. If the sea temperature rises by 2 to 4\u00b0 by 2100 due to climate change as the models predict, it will be very valuable to know which reefs are more \u201cfragile\u201d and need more protection from us.<\/p>\n

What is very nice with the crazy shifts that we do on-board is that light is up at all hours and we can see the Lofoten from the vessel in full daylight at 3 AM. This is quite an experience and makes you less tired when getting up in the middle of the night than it would usually do.<\/p>\n

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Sunset at 3:30 AM at the Lofoten. Picture: Narimane Dorey.<\/p><\/div>\n

Narimane Dorey<\/p>\n

\n

Bord -Experimente<\/h3>\n

13 Tage an Bord und die Experimente laufen gut. Ihr fragt euch wof\u00fcr diese ganzen Kabel und Dr\u00e4hte gut sind?<\/p>\n

Nun ja, meine Hauptaufgabe auf dem Schiff besteht darin Inkubationen zur Messung des Sauerstoffverbrauchs durchzuf\u00fchren. Dabei half mir f\u00fcr ein paar Tage Tina Kutti, die nun aber von dem PhD-Studenten \u00d8ystein Gjelsvik aus unserer Arbeitsgruppe am IMR (Insitute of Marine Research) in Bergen ersetzt wurde. Eigentlich machen wir normale Laborarbeit, allerdings f\u00fchren wir die Experimente anstatt in einem Labor auf einem sich bewegenden Schiff aus und anstatt in unseren eigenen Betten zu schlafen, schlafen wir nur wenig und in Schichten, um die Messungen unter Kontrolle zu halten.<\/p>\n

Das mag sich hart anh\u00f6ren, hat aber entscheidende Vorteile: wir bekommen frische, lebende Korallen und Meerwasser direkt aus dem Ozean unter uns und m\u00fcssen die Korallen nicht erst lange transportieren. Dadurch sind die Bedingungen im H\u00e4lterungstank an Bord auch viel n\u00e4her an der Realit\u00e4t im Riff als im Labor zu Hause und die Korallen m\u00fcssen sich nicht so lange eingew\u00f6hnen.<\/p>\n

Die Frage die uns besonders besch\u00e4ftigt, ist, wie Korallen auf Stress reagieren. Um sie unter Stress zu setzten, werden die Korallen in in ihrem H\u00e4lterungstank in mehreren Schritten immer h\u00f6hreren Temperaturen ausgesetzt. Wir starten bei in situ <\/em>Temperaturen von 5\u00b0C und steigern die Temperatur in 2\u00b0C Schritten auf 15\u00b0C alle 12 Stunden. Bis jetzt sind wir ziemlich fasziniert vom Durchhalteverm\u00f6gen der Korallen, die bei 15\u00b0C noch ziemlich gesund aussehen, obwohl sie im Riff bei 5-8\u00b0C leben.<\/p>\n

Das sind nat\u00fcrlich nur vorl\u00e4ufige Eindr\u00fccke. Nat\u00fcrlich messen wir auch ein paar Zahlen. Dazu setzen wir Korallenfragmente in geschlossene Kammern und messen die Atmung der Koralle. Heute und morgen arbeiten wir noch mit Korallen aus dem Steinavaer Riff. \u00d8ystein \u00f6ffnet und schlie\u00dft die Kammern und ich mache Notizen zu s\u00e4mtlichen Beobachtungen.<\/p>\n

Was wir sehen sollten, ist das die Atmungsrate ansteigt, wenn sie dem Temperaturstress ausgesetzt sind. Das ist wie bei Menschen, deren Atmung durch verschiedene Parameter beeinflusst wird. Zum Beispiel atmen wir schneller, wenn wir rennen und unsere Muskeln zus\u00e4tzlichen Sauerstoff ben\u00f6tigen. Korallen und andere Wirbellose funktionieren nat\u00fcrlich nicht genau wie Menschen aber ihre Atmungsrate steigt mit steigender Temperatur. Das ist keine neue Erkenntnis, aber was uns besonders interessiert, ist, ob Korallen von unterschiedlichen Riffen auch unterschiedlich auf Stress reagieren.<\/p>\n

Wir nehmen an, dass die Korallenriffe die sich n\u00e4her an der K\u00fcste befinden, nicht so stark auf den Stress reagieren wie Korallen die weiter von der K\u00fcste entfernt leben. Das ist die Arbeitshypothese f\u00fcr diese Expedition und dieses Experiment.<\/p>\n

Die oben beschriebenen Experimente dienen dazu diese Hypothese zu testen, aber wir benutzen auch weitere Stressmarker neben der Atmungsrate, die wir im Labor messen, wenn wir zur\u00fcck in Bergen sind. Worauf wir hoffen, ist, dass wir st\u00e4rkere Atmung in den gestressten Korallen messen und wir hoffen Unterschiede zwischen den verschiedenen Riffen zu finden. Das w\u00e4re die Best\u00e4tigung f\u00fcr unsere Hypothese.<\/p>\n

Aber auch wenn unsere Hypothese nicht best\u00e4tigt wird, w\u00e4re das sehr interessant. Die gesammelten Informationen sind besonders in Anbetracht des Klimawandels interessant. Wenn die Wassertemperaturen gegen Ende des Jahrhunderts um 2100 um 2 \u2013 4\u00b0C gestiegen sind, ist es wichtig zu wissen, welche Riffe besonders empfindlich sind und deshalb besonderen Schutz ben\u00f6tigen.<\/p>\n

Wirklich sch\u00f6n an den verr\u00fcckten Schichten an Bord ist, dass die Sonne immer scheint und wir dadurch die Lofoten um 3 Uhr morgens in vollem Tageslicht genie\u00dfen k\u00f6nnen. Das ist eine tolle Erfahrung.<\/p>\n","protected":false},"excerpt":{"rendered":"

[German translation below] On-board experiments Thirteen days on-board and the experiments are running smoothly. All those wires and cable ties for what, you ask? Well, my main task on this vessel is to run respiration incubations. I have had help from Tina for a few days and now she has been replaced by the PhD […]<\/p>\n","protected":false},"author":195,"featured_media":70,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-68","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-menschlicher-einfluss-auf-die-meere"],"_links":{"self":[{"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/posts\/68","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/users\/195"}],"replies":[{"embeddable":true,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/comments?post=68"}],"version-history":[{"count":2,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/posts\/68\/revisions"}],"predecessor-version":[{"id":75,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/posts\/68\/revisions\/75"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/media\/70"}],"wp:attachment":[{"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/media?parent=68"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/categories?post=68"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.oceanblogs.org\/pos525\/wp-json\/wp\/v2\/tags?post=68"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}