The following supplement accompanies the article

Oxygen budgets in subtidal arctic (Kongsfjorden, Svalbard) and temperate (Helgoland, North Sea) microphytobenthic communities

D. S. Sevilgen1,2,4,*, D. de Beer2, A. Y. Al-Handal3, T. Brey1, L. Polerecky2,5

1Alfred-Wegener-Institut, PO Box 120161, 27515 Bremerhaven, Germany 2Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany 3Marine Science Centre, Dept. of Marine Biology, University of Basra, Iraq

4Present address: Alfred-Wegener-Institut, Helmholtz Centre for Polar and Marine Research, Am Alten Hafen 26, 27568 Bremerhaven, Germany 5Present address: Faculty of Geosciences, Utrecht University, Budapestlaan 4, 3584 CD, Utrecht, The Netherlands

*Corresponding author: [email protected]

Marine Ecology Progress Series 504: 27–42 (2014)

 Further details on statistical analyses (Table S1), the species identified and their relative occurance (Table S2), porewater nutrient concentrations of the Svalbard sediment (Fig. S1) and the species distribution within the two study sites at Svalbard and Helgoland (Fig. S2)

Table S1. One-way ANOVA of comparisons between the 2 sites (Helgoland and Svalbard) with respect to various parameters describing the site or its MPB community

Parameter df F p

Permeability 1 11.83 0.08 Porosity 4 6.03 0.04 C:N 5 3.42 0.09 chl a 5 0.08 0.78 Fucoxanthin 5 0.06 0.81 Pnet 2 0.29 0.62 Pgross 2 0.13 0.73 Rphot 2 0.06 0.05



Table S2. and abundances of the identified from the studied sites in Helgoland and Svalbard. Abundances are quantified as frequent (+++), rare (++), very rare (+) and absent (-) (see ‘Materials and methods: Diatom identification’ in the main article for definitions)

CLASS ORDER FAMILY GENUS SPECIES frequency Hel / Sval Bacillariophyceae Naviculales Sellaphoraceae Fallacia forcipata ++ / ++ Diploneidaceae Diploneis smithii +++ / +++ bomboides ++ / ++ cf. notabilis - / ++ cf. sp. - / ++ suborbicularis ++ / - Naviculaceae Seminavis sp. - / ++ Navicula directa - / +++ karianria var. - / ++ Frigida sp. - / ++ cancellata +++ / - cf. pinnata ++ / - Pinnulariaceae Pinnularia quadratarea - / + Plagiotropidaceae Plagiotropis Lepidoptera - / +++ Pleurosigmataceae Pleurosigma normanii - / ++ sp. ++ / - reticulatum ++ / - Donkinia carinata - / +++ Achanthales Achanthidiaceae Planothidium delicatulum - / +++ Achnanthaceae Achnanthes sp. + / ++ fimbriata + / + Thalassiophysales Catenulaceae Amphora marina ++ / +++ cf. arenaria ++ / ++ sp. ++ / ++ acutiuscula + / ++ cf. obtusa - / ++ levitisima - / ++ lineolata - / ++ crassa - / + sulcata - / +++ Bacillariales Bacillariaceae Nitzschia hybrida - / ++ sp. - / ++ Lyrellales Lyrellaceae Petroneis marina +++ / ++ humerosa +++ / - Lyrella abrupta ++ / - Centrales aurita ++ / ++ Fragilariales Fragilariaceae Opehora sp ++ / - Anaulales Anaulaceae Eunotogramma marinum + / - Triceratiales Tricerateaceae Auliscus sculptus + / - Coscinodiscales Hemidiscaeae Actinocyclus actinochilus + / -

  

[μM] [μM] [μM] [μM] [μM] 0 1020304050 0.0 0.2 0.4 0.6 0.8 1.0 0 5 10 15 20 25 012345 0 5 10 15 0 17.06.10 -2 22.06.10 29.06.10 05.07.10 -4

-6

depth [cm] depth -8

-10

-12 Nitrate Nitrite Ammonium Phosphate Silicate Fig. S1. Vertical profiles of porewater nutrients in the Svalbard sediment extracted in situ with rhizones (open symbols). Filled symbols show nutrient concentrations in the overlaying water. Data represent measurements done on different dates (see key). When available, error-bars indicate SD of 2 replicate measurements. Comparable data for the Helgoland site is not available due to sample loss during transport. 

Donkina carinata Plagiotropis lepidoptera Planothidium delicatulum Diploneis smithii Navicula cancellata Amphora sulcata Petroneis marina Petroneis humerosa Pleurosigma normanii Amphora marina Navicula directa Navicula cf. Pinnata Opephora sp. Amphora cf. obtusa Amphora cf. arenaria Pleurosigma reticulatum Amphora levitisima Amphora sp. Pleurosigma sp. Amphora lineolata Diploneis bomboides Diploneis suborbicularis Seminavis sp. Fallacia forcipata Lyrella abrupta Navicula kariana var. frigida Odontella aurita Navicula sp. Actinocyclus actinochilus Nitzchia hybrida Amphora acutiuscula Auliscus sculptus

Nitzschia sp. Achnanthes sp. Eunotogramma marinum Diploneis cf. notabilis Achnanthes fimbriata Diploneis sp. HELGOLAND

Amphora crassa Pinnularia quadratarea SVALBARD

Fig. S2. Diatom species distribution between the 2 studied sites in Helgoland and Svalbard. The font sizes from largest to smallest indicate relative abundance, given as frequent, rare, and very rare.