The Mesocosm Lab


We designed this outdoor, flow-through seawater lab so that replicated experiments can be conducted under realistic environmental conditions. This unique system blends the realism of field conditions with the high degree of control necessary for mechanistic experiments.


Seawater from Vineyard Sound is delivered as quickly as 85 gpm (322 lpm) by a dedicated pump. The tanks can be supplied with whole (i.e., untreated) or filtered seawater at temperatures that are warmer, cooler, or the same as Vineyard Sound. Flow rates are controlled at each tank.

Filters. Water is sequentially filtered through 1 of 2 sets of redundant filters.

Security. The dedicated pump is connected to the WHOI central station for alarm coverage. A backup water system is available.  The entire Lab is on emergency, back-up power.

12 large tanks are constructed of fiberglass, 9’ long x 4’ wide x 2.5’ deep.  The tanks can be subdivided to increase experimental replication. For instance, each large tank can hold 8, 210L tanks or 18, 19L tanks.

Facilities. Fresh and salt water hoses; sieving area; compressed air; climate controlled shed; loading dock; motion-sensitive exterior lights; radiant heat.

Electrical outlets (120V, 20 amp) are at each tank, the lab bench, and in the shed. Power is available anywhere in the Mesocosm Lab. Electrical boxes can be suspended above the tanks and moved along tension wires.

Data.Ethernet ports are at each tank, the lab bench, and in the shed. Data boxes at each tank can send information to or receive data from instruments. Each box has:

• 5-port ethernet switch
• 4-port USB to ethernet
• 4-port RS 232 to ethernet
• Network power controller
• Outlet multiplier


Oceanus Magazine made a video about the Mesocosm Lab highlighting an experiment with marsh grasses.
Take an audio tour to learn about specific features of the Mesocosm Lab.

Publications from the Mesocosm Lab.

Nelson, J., D. Johnson, L. Deegan, A.C. Spivak, and N. Moore. Geomorphology modifies bottom-up control on food webs. In review.

Spivak, A.C. and J. Ossolinski. 2016. Limited effects of nutrient enrichment on bacterial carbon sources in salt marsh tidal creek sediments. Marine Ecology Progress Series 544: 107-130

Spivak, A.C. and J. Reeve. 2015. Rapid cycling of recently fixed carbon in a Spartina alterniflora system: A stable isotope tracer experiment. Biogeochemistry 125: 97-114 10.1007/s10533-015-0115-2

Spivak, A.C. 2015. Benthic biogeochemical responses to changing estuary trophic state and nutrient availability: A paired field and mesocosm experiment approach. Limnology and Oceanography. 60(1):3-21