1. Estuaries 101 A Brief Introduction to Natural and Human-Induced Processes in Estuaries Jonathan Pennock University of New Hampshire Marine Program, NH Sea Grant & Jackson Estuarine Laboratory

2. What Are Estuaries and Why Should We Care About Them? Semi-enclosed bodies of water where fresh water & salt water mix… Estuaries are critical habitats for many ecologically and economically important coastal species… Estuaries are natural biological and geochemical reactors… While net flow is almost always from the land to the sea, tidal influences and often two-layered flow tend to retain materials in estuaries… In most, but not all estuaries, freshwater input from the watershed is the major source of nutrients, contaminants, suspended sediments, etc… The sources of these inputs varies, however, with ‘point-sources’ from specified inputs and ‘non-point sources’ from varied sources such as precipitation, agriculture, septic tanks and groundwater contributing… Different estuaries have differing capacities to cope with human perturbations based on their physical and geological make-up…

3. What are the Most Critical Factors Impacting Estuaries? Habitat Loss Bacterial Contamination Chemical Contaminants Loss of Keystone Species Sediment Inputs Nutrient Over-Enrichment Micro-algae and Macro-algae Overgrowth Hypoxia & Anoxia

4. NOAA Eutrophication Model Bricker 1999

5. Eutrophication Positive Versus Negative Effects OligotrophicMesotrophicEutrophic Dystrophic Phytoplankton Zooplankton Pelagic Fish Bottom Oxygen Benthos Benthic Fish

6. Population Increase Adapted from Nixon, 1994

8. Land Clearing

10. Land Clearing & Agriculture

12. Fertilizer Production Adapted from Nixon, 1994

13. Intensive Agriculture

14. Point Source Inputs

15. Headlines from Other Regions [We are Not Alone in Our Concerns…]

16. Mobile Bay A Case Study In Nutrient Biogeochemistry Research Mobile Bay, Alabama – Sorting Through Variability

19. Dog RiverFowl RiverWeeks Bay Developed24.6%1.7%0.8% Forested39.7%41.2%29.8% Agriculture20.3%33.4%59.9% Wetland11.2%18.5%5.6%

21. NOAA Estuarine Eutrophication Assessment Bricker 1999

22. Environmental Protection Agency

23. Thank You!