1. A buffet the size of the ocean! The heterotroph group: Alison Dominy, Sean Lu, Ellen Winant

2. GOALS A. Compare animal abundance within the benthos and water column. B. Investigate heterotrophic processes that influence rates of exchange of matter and energy between the water column and the benthos.

3. Zooplankton Feeding Experiment Unusually high rates of ingestion and volume swept clear (VSC).

4. Data and the Studies Top graph redrawn from Frost, 1972. Bottom graph redrawn from Redrawn from Paffenhofer and Lewis, 1990 unstarved starved Phytoplankton Concentration Ingestion rate Phytoplankton Concentration Volume Swept Clear JarCopepod stageIngestion (cells/copepod/day) A2 stage V8878 D3 stage V7463.8 C t 1 2 stage V8101.2 C t 2 2 stage V20382.6 B t 1 2 stage IV850.2 B t 2 2 stage IV1986

5. THE Salp Invasion! Oh Noes! Salps asexually reproducing Is the beginning stage of an upwelling an optimal environment for Salp (Thaliacea) growth? -Colder temperatures. -Slight increase in nutrient concentration. -Little competition with copepods for food. -Leads to increased Organic Carbon……

6. Comparison of Animal Density within Cores to Zooplankton within the Water Column “As a life’s work, I would remember everything-everything, against loss. I would go through life like a plankton net.” – Annie Dillard -Well, if Annie was to go through life with our plankton net, she would miss a wealth of information. Sampling with our 500 micromesh excluded many of the smaller plankton-an order of magnitude to be precise.

7. Benthos Animal Density Mean number of benthic organisms at R2 = 833 individuals / m 2. Based on literature values, zooplankton abundance in the water column is at least an order of magnitude greater.

8. Core Analysis Cores were taken for fine sediment, chlorophyll, and ammonium analysis Samples taken every 1 cm for fine sediment and chlorophyll analysis.

9. Sediment Fines We might expect lower organic material because of greater mineralization rates Possible higher levels of inorganic fines because less mixing

10. Ammonia Concentration within the Pore Water R. Jahnke et al. 2005. Late Summer- at 27 meters in SAB June 2008- at 27meters in SAB

11. Remineralization Estimates -Remineralization is highest in the upper cm’s of the sediment. -Amount of carbon found in the sediment was less than Jahnke’s findings. The data collected by KSU students on the R/V Savannah June 19 and 20th 2008 compared to the data used in the R. Jahnke 2005 paper for the rate of carbon remineralization in sediment cores. mmol/m^2 day KSU 6.55 Jahnke 20.5

12. Organic matter Primary Productivity CO 2 NH 4 CO 2 NH 4 Remineralization Decompostion CO 2 NH 4 >700 mgC/m 2 /d 679 mgC/m 2 /d Primary Productivity 78.6 mgC/m 2 /d Zooplankton grazing e.g. Eucalanus pileatus only 16 ugC/ind./d WATER COLUMN BENTHIC SEDIMENTS CO 2 NH 4 ? An overview of water column and benthos rates

13. The Water Column and Benthic Interaction An Open and Dynamic Filtration System Organic carbon input from the water column (from organisms such as (eucalanus pileatus)+ tidal and current-bottom interactions  remineralization within the sediment by heterotrophic bacteria  inorganic carbon and nitrogen advected back out due to tidal current-bottom interactions/ripples.

14. Conclusions Unusually high feeding for Eucalanus suggesting low food concentration and high abundance of salp support the upwelling hypothesis. Low rates remineralization relative to primary production suggest that the system is not in steady state. Remineralization rate may increase later as production subsides.

15. “GOODBYE”