GEOMAR-Helmholtz Center for Ocean Research
West shore campus
Düsternbrooker Weg 20
East shore campus
Description of the infrastructure: The GEOMAR Kiel-Outdoor-Benthocosms (KOB) designed to simulate future underwater conditions expected under climate change has been successfully used since 2012. The facility consists of 6 experimental units holding 3000 L each, which can be sub-divided into 12 autonomous units of 1400 l. Covers translucent to all solar wave lengths can be used if headspace conditions need to be controlled. Water movement and turbulence is controlled by water through-flow, internal circulation and wave generators to produce a wide range of hydrodynamic conditions. Natural upwelling events are simulated with a deep-water hose supplying water from below the thermocline. Possible simulations include abrupt changes in salinity, O2, pH, pCO2 and nutrients. The entire infrastructure, including a container with master computers, freezers and workshop, is installed on a floating platform.
A unique feature of KOB is that it can track the short-term fluctuations characterising natural regimes of environmental factors, such as temperature, pCO2, O2 and nutrient concentrations. It is operated in flow-through mode to create in- situ conditions in real-time by adjusting the climate-change factors of interest to dynamic target values based on the experimentally desired deviation from a continuously recorded baseline in the field. Adjustments to the target values are fully automated by means of a sophisticated instrumentation and control (I&C) system that also records a range of environmental variables continuously. Novel software serves to mimic the exact regimes of temperature, pH, O2 and other environmental factors of a given year in the past or any deviations from those conditions.
off-shore/outdoor/indoor – pelagic/benthic – marine/brackish
Kiel Outdoor Benthocosms – KOB
outdoor – benthic – marine/brackish
Floating infrastructure consisting of sub-dividable 3500 liter tanks, optionally covered by a fully translucent hood. When the system works in a flow-through mode all in situ fluctuations are admitted to the tanks and experimental treatments represent controlled deviations (delta-treatments) from this naturally fluctuating baseline
KOB: CO2, temperature, irradiation, nutrients, oxygen, salinity
KOB: responses of benthic communities to environmental shifts/fluctuations in temperature, pH, pCO2, oxygen, nutrients, salinity