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Research Overview

Benthic ecosystem functioning, anthropogenic impacts and climate change

The Witte group investigates the functioning of benthic marine ecosystems and benthic-pelagic coupling  from the deep ocean floor to the intertidal, with a current focus on consequences of both anthropogenic activities  and climate change.

This often includes  the development of new research technologies, and one focus of ongoing work is the development of a pressurised coring, incubation and cultivation system for the study of biogeochemical processes and piezophile  microorganisms from the deep seafloor under varying environmental conditions (pH, T, O2 etc).

Sea ice is a unique feature of polar marine ecosystems and the fact that small temperature differences can have large effects on the extent and thickness of this sea ice makes polar marine ecosystems particularly sensitive to climate change.  The group’s  work on climate change impacts on benthic ecosystem functioning is therefore centred in both the Arctic and the Antarctic peninsula where change is particularly rapid.

In many cases, stable isotope tracing experiments, often carried out in situ at the deep-sea floor,  help us track the pathway of organic matter, in particular C and N,  through the benthic community and thus understand the spatial and temporal dynamics of biological and geochemical transformations of matter in benthic and benthopelagic foodwebs.

But we also work closer to home: Aberdeen is often referred to as the ‘oil capital of Europe’, and with hydrocarbon extraction now occurring down to 1100 m in the Faroe Shetland Channel, a need arises to understand the consequences of accidental releases in Scottish deep water environments in order to improve monitoring and optimize response measures after a spill. Several ongoing projects therefore investigate the rates and pathways of hydrocarbon degradation in Scottish Waters, as well as the microorganisms involved.

Funding and Grants

Transformation of Antarctic Benthic Food Webs on the Larsen Ice Shelf following Loss of Sea-Ice Cover (TABOSI). 2019-2021. Polarstern Nebennutzerantrag. PI Witte. 

Benthic biodiversity under Antarctic ice-shelves - baseline assessment of the seabed exposed by the 2017 calving of the Larsen-C Ice Shelf. NERC urgency application; 2018-19, CoI, PI Linse.

Continuous observation of deep-sea benthic community structure and benthic-pelagic coupling throughout the polar night and summer ice melt.   NERC Arctic office. PI Witte 2017-2018

Using the intrinsic recovery capabilities of deep-sea and polar ecosystems to reduce the impact of accidental oil release. NERC Oil and Gas DTP. PI Witte, 2014-2018

Increasing oil spill preparedness for Scottish deep waters  - the role of sediments in a deep water oil spill. MarCRF. PI Witte with A. Gallego and J. Anderson. 2014-2018

Fate and flow of oil carbon in the marine food web – towards efficient monitoring of oil contamination. NERC  CASE PhD studenthsip 2014- 2018.  PI Witte

The natural capacity for oil degradation of marine environments.   NERC PI Witte with J. Anderson and E. Gontikaki. £98,871, 2013-2015.

ArcDeep: Deep-sea ecosystem functioning in a changing climate: consequences of changing sea-ice cover for Arctic benthic ecosystems . NERC standard grant proposal; PI Witte, with F. Kuepper. £508,490, Appr. 2013 – 2017

MAC-EXP: A pressurised coring, experimentation and cultivation system for deep-sea sedimentary ecosystems. NERC Technology-led standard grant.2012-2014. Lead: Witte (Aberdeen), with Parkes, (Cardiff). Awarded. £552000. 2013- 2017.

PharmaSea: Planet Ocean – Streamlining the Marine Biodiscovery Pipeline.  EC FP7-KBBE-2012-6(PI: M Jaspers. Total volume 10 Mio €. Aberdeen: € 725000. 2012- 2017

"The role of micronutrients in deep-sea carbon cycling".  The Leverhulme Trust, 2007 -2010

Bacterial Diversity and Carbon Turnover at the Abyssal Seafloor –proposal to apply 454-based tag sequencing technology to deep-sea sediments. Keck foundation – 2008/ 2009.

"Rates and pathways of carbon cycling at the abyssal sea floor: a long-term, in situ experimental study". NERC, 2007-2010

HERMIONE –– Hotspot Ecosystem Research at Continental Margins; April 2009- September  2012.

Carnegie Trust – Development of Scottish resources for seafloor biogeochemical process studies. August 2008 – July 2010. £29800

"Nutrient regeneration in North Sea coastal sediments". FRF, 2006-2009

"Carbon turnover and trophic relationships in theabyssal Pacific", NERC-LSMSF, 2007/08

COBO - Towards a Coastal Ocan Benthic Observatory  (EC) 2004 - 2007

Teaching Responsibilities

SX1015 The Oceans and Society in a changing environment. 6th century course. Course coordinator and coordiantor theme 1.

BI 1006 BUGS (Biology for Undergraduates) tutor Marine Biology

BI25Z4 Ocean Biology

ZO3306 Marine Ecology and Ecosystems

BI39Z1 Marine Ecology Florida field course

ZO4542 Marine Benthic Ecology

BI4517, BI4017 SBS Honours Essay

BI4016 SBS Honours Project