Evaluating the Influence that Anthropogenic Inputs have on Carbon and Nitrogen Cycling and on the Biological Assemblages in Tampa Bay, FL David Hollander, Elon Malkin, Ed Van Vleet College of Marine Science, St. Petersburg, FL 33701 in collaboration with T. Edgar, T Cronin, P. Swarzenski, K. Yates, USGS Program Leaders Project Objectives: Determine how historical human influences have: • Altered the geochemical cycling of carbon and nitrogen (today’s presentation) • Modified ecosystem structure as recorded in the inputs of sedimentary organic matter.
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Evaluating the Influence that Anthropogenic Inputs have on Carbon and Nitrogen Cycling and on the Biological Assemblages in Tampa Bay, FL
Evaluating the Influence that Anthropogenic Inputs have on Carbon and Nitrogen Cycling and on the Biological Assemblages in Tampa Bay, FL David Hollander, Elon Malkin, Ed Van Vleet College of Marine Science, St. Petersburg, FL 33701 in collaboration with - PowerPoint PPT Presentation
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Evaluating the Influence that Anthropogenic Inputs have on Carbon and Nitrogen Cycling and on the Biological
Assemblages in Tampa Bay, FL
David Hollander, Elon Malkin, Ed Van VleetCollege of Marine Science, St. Petersburg, FL 33701
in collaboration withT. Edgar, T Cronin, P. Swarzenski, K. Yates, USGS Program Leaders
Project Objectives: Determine how historical human influences have:
• Altered the geochemical cycling of carbon and nitrogen (today’s presentation)
• Modified ecosystem structure as recorded in the inputs of sedimentary organic matter.
Research StrategyField studies:
•Sediment coring throughout Tampa BayAnalytical approach:
•Organic carbon and nitrogen concentrations– reflects increasing input & production of organic matter– C:N Ratios determine algal vs terrestrial inputs
•Stable Isotopes of organic carbon and nitrogen– reflects specific nutrient inputs and assimilation– trophic relationships
Nitrogen Isotope Fingerprinting of Nutrient Inputs
Safety Harbor-Residential
Terra Ceia-Agriculture
Hillsborough-Urban
Linking Sedimentary & Land-Use Records:
•TON/TOC- 4x increase due to nutrient input and increased production•Transition from vascular plant to algal/bacterial inputs (C:N, biomarkers)•Enriched 15N > 10 ‰, coprastanol reflect wastewater-industrial inputs
1952 1995
TOC, Wt% C/N, Atomic Ratio 15N, ‰ Air
Dep
th (
cm)
Algal Terr Plants Soil Urban
TON, Wt%Fertilizer/Ter Plant
Redeposited layer
Hillsborough Bay/Alafia River Urbanization/Industrialization
Hum
anIm
pact
Linking Sedimentary and Land-Use Records1952
•Increasing nutrient inputs leading to production (TOC/TON)•Transition from vascular plant to algal/bacterial inputs (C:N, biomarkers)•15N- Agricultural nutrient mimic vascular plant inputs, recent urban
1995D
epth
(cm
)
Agricult/TerPlant
TOC, Wt% C/N, Atomic Ratio 15N, ‰ Air
TON, Wt%
Terra Ceia/Aquatic PreserveAgricultural
Recent urbanization
Soil
Urban
UrbanFertilizer/Terr Plants
Algal Terr Plants
Hum
anIm
pact
Alafi
a
Linking Sedimentary and Land-Use Records
1952 1995
•Delayed geochemical response reflects later land use development•Abrupt transition to algal/ bacterial inputs•15N reflects increasing residential inputs