Measuring aquatic ecosystem Measuring aquatic ecosystem metabolism - PowerPoint PPT Presentation

Measuring aquatic ecosystem Measuring aquatic ecosystem metabolism in the southern Everglades metabolism in the southern Everglades Gregory R. Koch 1 , Peter A. Stæhr 2 , Evelyn E. Gaiser 1 and Daniel L. Childers 3 1 Department of Biological Sciences, Florida International University Miami, FL, USA 2 University of Copenhagen Hillerød, Denmark 3 Global Institute of Sustainability, Arizona State University Tempe, AZ, USA

Introduction Methods Results Analyses Conclusions Everglades National Park Historic Miami Flow Shark River Slough Taylor Slough Current Flow Gulf of Mexico Florida Bay Planned Flow http://fcelter.fiu.edu/data/GIS/interactive_map/ http://www.evergladesplan.org

Introduction Methods Results Analyses Conclusions The Taylor Slough Watershed Miami Taylor Slough Taylor River Florida Bay Photos: http://fcelter.fiu.edu/about_us/photos/ Map: http://fcelter.fiu.edu/data/GIS/interactive_map/

Introduction Methods Results Analyses Conclusions Taylor River TS/Ph 6 Photo by Steven Davis Study Sites TS/Ph 7 http://fcelter.fiu.edu/about_us/photos/ http://fcelter.fiu.edu/data/GIS/interactive_map/

Salinity (ppt) 10 20 30 40 50 60 0 May-98 Sep-98 Jan-99 Introduction May-99 Sep-99 Jan-00 Taylor River Seasonality May-00 Sep-00 Jan-01 Methods May-01 TS/Ph6 Sep-01 http://fcelter.fiu.edu Jan-02 May-02 Sep-02 Jan-03 Results May-03 Sep-03 Jan-04 May-04 Sep-04 Analyses Jan-05 May-05 ~35ppt Seawater Full-strength Conclusions

Introduction Methods Results Analyses Conclusions Taylor River Seasonality TS/Ph 6 http://fcelter.fiu.edu 50 45 1998 40 1999 35 2000 Salinity (ppt) 30 2001 25 2002 20 2003 15 2004 10 2005 5 0 J F M A M J J A S O N D Blue – Oligohaline “Wet” Season – September to February Red – Euhaline “Dry” Season – March to August

Introduction Methods Results Analyses Conclusions Taylor River Seasonality 2008 - 2009 50 FCE LTER Site TS/Ph 6 (Upstream) FCE LTER Site TS/Ph 7 (Downstream) 3-day Smoothed Average 40 Average 30 Salinity (ppt) 20 10 0 “Wet” Season “Dry” Season Nov Jan Mar May Jul Sep

Introduction Methods Results Analyses Conclusions What is ecosystem metabolism? • metabolism: the sum of all chemical changes in living cells by which energy is provided for vital processes and activities and new material is assimilated (Merriam-Webster Dictionary) • In Ecosystems: the biological activity of all living organisms within the ecosystem boundary; generally, primary production and respiration Ecosystem Boundary Light consumption Production Autotrophs Heterotrophs Respiration

Introduction Methods Results Analyses Conclusions What does ecosystem metabolism tell us? The balance of carbon between the ecosystem and its surroundings: Gross Primary Production (GPP) Ecosystem Respiration (R) NEP = GPP - R Net Ecosystem Production (NEP) Ecosystem Boundary Light consumption Production Autotrophs Heterotrophs Respiration

Introduction Methods Results Analyses Conclusions How does metabolism change with time? Oligohaline “Wet” Season Euhaline “Dry” Season R e GPP R GPP R GPP + Low Salinity + High Salinity + Submerged Aquatic + No SAV Vegetation (SAV) + Low Water Depth + High Water Depth + Low Sediment Depth + High Sediment Depth = Lower GPP, Higher R = Higher GPP, Lower R

Introduction Methods Results Analyses Conclusions Calculating Metabolism Floating Buoy Design Anemometer Temperature and Dissolved Oxygen Light loggers sensor Variables Measured % Dissolved Oxygen Wind Speed Water Temperature Underwater Light Surface Light

Introduction Methods Results Analyses Conclusions Calculating Metabolism Δ O 2 / Δ t = GPP – R – F atm Vind Wind Atmospheric exchange (F) o C Epilimnion GPP GPP Phytoplankton Turbulent ∆ DO Summer mixing Winter Phytoplankton, R R animals, bacteria Metalimnion R Advection Hypolimnion Sediment Staehr, P.A., C.E. Williamson, M.C. Van de Bogert, T.K. Kratz, G.R. Koch, P.C. Hanson, J.J. Cole, D.L. Bade. In Prep .

Introduction Methods Results Analyses Conclusions Calculating Metabolism Δ O 2 / Δ t = GPP – R – F atm F atm (gO 2 m -2 h -1 ) = k (O 2 meas – O 2 sat) k (cm h -1 ) = k 600 ( Sc /600) -0.5 k 600 (cm h -1 ) = 2.07 + 0.215(wind 10m ) 1.7 Sc = 0.0476(T) 3 + 3.7818(T) 2 - 120.1(T) + 1800.6 wind 10m = wind Z (1.4125 (z -0.15 )) Staehr, P.A., C.E. Williamson, M.C. Van de Bogert, T.K. Kratz, G.R. Koch, P.C. Hanson, J.J. Cole, D.L. Bade. In Prep . Jähne, B., O. Münnich, R. Bösinger, A. Dutzi, W. Huber, and P. Libner. 1987. Journal of Geophysical Research 92: 1937-1949. Cole, J.J. and N.F. Caraco. 1998. Bioscience 38:764-769. Smith, S.V. 1985. Plant, Cell, and Environment 8: 387-398. Wanninkhof, R. 1992. Journal of Geophysical Research 17: 721-735.

Introduction Methods Results Analyses Conclusions Water Temperature Profiles 40 40 Pond 3 Pond 4 P4 10cm 35 35 P4 50cm P4 100cm 30 30 °C °C 25 25 20 P3 10cm 20 P3 50cm 15 15 P3 100cm 10 10 Feb Mar Apr May Jun Jul Aug Nov Jan Mar May Jul 36 Pond 5 34 32 °C 30 P5 10cm 28 P5 50cm P5 100cm 26 Jul Aug

Introduction Methods Results Analyses Conclusions Daily Metabolic Rates 800 800 Pond 4 Pond 3 P3 GPP P4 GPP 600 600 P3 R P4 R 400 P3 NEP 400 P4 NEP mmol O 2 m 3 d -1 mmol O 2 m 3 d -1 200 200 0 0 -200 -200 -400 -400 -600 -600 -800 -800 -1000 -1000 May Jun Jul Aug Nov Dec Jan Feb Mar Apr May Jun 800 Pond 5 P5 GPP 600 P5 R P5 NEP 400 mmol O 2 m 3 d -1 200 0 -200 -400 -600 -800 -1000 Feb Mar Apr May Jun Jul Aug

Introduction Methods Results Analyses Conclusions Seasonal Differences 800 600 t = 7.0392 400 p < 0.0001 df = 188 200 mmol O 2 m -3 d -1 0 -200 t = -8.8637 -400 p < 0.0001 df = 188 -600 t = -0.6640 p = 0.5075 -800 df = 188 -1000 -1200 P4 Wet GPP P4 Dry GPP P4 Wet R P4 Dry R P4 Wet NEP P4 Dry NEP

Introduction Methods Results Analyses Conclusions Spatial Differences 800 600 400 200 mmol O 2 m -3 d -1 0 -200 -400 -600 -800 -1000 -1200 P3 GPP P4 GPP P5 GPP P3 R P4 R P5 R P3 NEP P4 NEP P5 NEP

Introduction Methods Results Analyses Conclusions Drivers of Aquatic Production Green Cells = Significant Positive Correlation Red Cells = Significant Negative Correlation α = 0.05 Surface 50cm Kd TP Temp Salinity Wind Light Light 0.268 0.201 -0.155 -0.302 0.454 -0.010 N/A Pond 3 GPP p = 0.032 p = 0.111 p = 0.221 p = 0.015 p < 0.001 p = 0.937 0.595 0.081 -0.099 0.007 0.365 0.572 0.235 Pond 4 GPP p = 0.367 p = 0.967 p < 0.001 p < 0.001 p = 0.001 p < 0.001 p = 0.409 0.314 -0.353 -0.429 -0.414 0.746 0.517 N/A Pond 5 GPP p < 0.001 p = 0.107 p < 0.052 p < 0.001 p < 0.001 p < 0.001

Introduction Methods Results Analyses Conclusions Our Predictions… Oligohaline “Wet” Season Euhaline “Dry” Season R e GPP R GPP R GPP + Low Salinity + High Salinity + Submerged Aquatic + No SAV Vegetation (SAV) + Low Water Depth + High Water Depth + Low Sediment Depth + High Sediment Depth = Lower GPP, Higher R = Higher GPP, Lower R

Introduction Methods Results Analyses Conclusions So, What Really Happened? Oligohaline “Wet” Season Euhaline “Dry” Season R e GPP R GPP R GPP + Low Salinity + High Salinity + Submerged Aquatic + No SAV Vegetation (SAV) + High TP?? + Low Water Depth + High Water Depth + Low Sediment Depth + High Sediment Depth = Higher GPP, Higher R = Lower GPP, Lower R

Introduction Methods Results Analyses Conclusions Directions of New Research • Expand spatial and temporal breadth of data • Explore the relationship between stimulated GPP and responses in R • additions of algal extracts onto pond sediments (“priming”) • Time series analysis to explore time lags • Investigate the meaning of metabolic throughput in terms of ecosystem function • Floc transport rates between ponds • Carbon budgets and landscape metabolism estimates for Taylor River