Benthic primary production will be estimated using chambers designed to measure oxygen evolution and carbon uptake. These chambers provide a volume to estimate productivity and respiration for a given biomass of flora and fauna. Our chambers used thin polycarbonate panels formed into a pyramid shape with a wide skirt which provided a durable chamber that would survive the Aleutians, was flexible providing transmission of wave energy, sealed to the benthos preventing mixing with the surrounding water, and encompassed representative benthic communities.
To measure changes in temperature, oxygen, and light, and how this may differ with using chambers, sensors recording these variables were placed within and outside of each chamber.
To measure changes in temperature, oxygen, and light, and how this may differ with using chambers, sensors recording these variables were placed within and outside of each chamber.
MEASURING LARGE PRIMARY PRODUCERS
Estimating the productivity and respiration of large canopy forming species is difficult. The dominant kelp Eualaria fistulosa can be 10s of meters long therefore production and respiration will be estimated using pieces of kelp within closed bags. These polyvinyl bags will be filled with ambient water (1 liter) and a piece of kelp from either near the surface or the benthos will be placed inside and hung at their respective depths on buoy lines to estimate oxygen production at these locations by Eualaria. The oxygen concentration will be measured before and after incubation and repeated to provide information on rates of production throughout the day and among days.
Estimating the productivity and respiration of large canopy forming species is difficult. The dominant kelp Eualaria fistulosa can be 10s of meters long therefore production and respiration will be estimated using pieces of kelp within closed bags. These polyvinyl bags will be filled with ambient water (1 liter) and a piece of kelp from either near the surface or the benthos will be placed inside and hung at their respective depths on buoy lines to estimate oxygen production at these locations by Eualaria. The oxygen concentration will be measured before and after incubation and repeated to provide information on rates of production throughout the day and among days.
DEPLOYING AND RETRIVING THE CHAMBERS
|
With 9 chambers ((3) deployed in kelp, (3) in a kelp/urchin area, and (3) in urchin barren habitats), 19 pieces of chain to help hold chambers in place when deployed, 9 buckets with weights for incubation bags deployments, and our dive gear, the boats were full.
|
|
|
|
BUILDING THE CHAMBERS
|
|
TESTING CHAMBER DESIGNS
|
Our preliminary chamber design was very different from the final design.
|
We tested deploying the benthic chambers in Catalina to see how well they worked in a rocky reef habitat.
|
