AREC 200 Introduction to the Chesapeake Bay 03 30 2011 Why did the bay form here with these characteristics Geological forces 35 mil years ago a meteor hit the region created blast splash sent water 30 miles into the air and came crashing down catastrophic 1983 a lot of exploration for drinking water and oil and gas found meteor evidence Everything since meteor has been affected geologically by impact Bolide meteor impact Ice age Drowned river valley 3rd version Middle of bay from N to S is a very deep shipping channel Moved from E to W over thousands of years 3 times Climate change ice ages The Chesapeake is shallow 18 21 feet Compared to other main water areas around world it is extremely shallow Therefore less water volume Volume how much water in the bowl watershed how much of land is impacting water and size of bowl o If water in an area drains to bay it is in watershed Extensive watershed and airshed Watershed volume ratio is HUGE Compared to any other marine costal system size of watershed is massive Impact of land is critically important o Big political implications who you have to involve when dealing with Chesapeake bay problems NY state is so far but they impact Airshed is even bigger goes past Ohio o Airshed an area is in airshed if 75 of pollution particularly nitrogen impacts the bay 200 miles N to S average width is 30 miles perimeter should theoretically be 460 miles BUT because of indented coastline there is much more land water interaction longer than West Coast of US o Much more opportunity for land to impact water Delaware Chesapeake canal Atlantic ocean bay interaction Manmade connects Chesapeake bay and Delaware Bay the solution to pollution is dilution if bay water could mix with ocean water But there is a very narrow opening Restricted exchange with ocean Bay is relatively closed system What we do on land is sure to be reflected on bay AREC200 Estuary 03 30 2011 An estuary is a partially enclosed body of water and its surrounding costal habitats where saltwater from the ocean mixes with fresh water from rivers or streams Largest estuary in North America Political definition drainage Lakes Types Geologic Classification The term estuary means a part of a river or stream or other body of water that has an unimpaired connection with the open sea and where the sea water is measurably diluted with fresh water derived from land The term also includes near coastal waster and wetlands of the Great o Drowned river valley ria coastal plain o Fjord o Bar built o Delta Water Circulation of Stratification o Salt wedge o Partially mixed o Vertically homogeneous well mixed fresh salt mixed all the way Factors Impacting Circulation and Mixing through Precipitation Tides Coriolis Winds create mixing direction of winds Living Resources Limiting Nutrients Phytoplankton Energy originates from sun and plants grow and reproduce using photosynthesis Zooplankton microscopic animals that eat the plants Organisms needs nutrients in different ratios for growth and development Freshwater Systems Phosphorus tends to be the limiting nutrient There s more nitrogen available than the plants can use so if you add more phosphorus you stimulate growth Estuarine Systems Nitrogen tends to be the limiting nutrient There s more phosphorus than the plants can use so if you add more nitrogen you stimulate growth Eutrophicaton Increased nutrients o Excessive growth of phytoplankton and macroalgae grazers cannot control growth Large scale blooms block sun to SAV Different species some harmful may dominate o Eventually deplete nutrients and die Bacterial decomposition consumes oxygen Hypoxia less than 2 3 ppm dissolved oxygen Anoxia no oxygen SUMMARY Chesapeake is a partially mixed estuary Precipitation storm events leads to excessive inputs of nutrients and sediments Nutrients stimulate primary production creating large dense algal blooms Blooms die and decomposition consumes oxygen making parts of the Bay hypoxic and anoxic AREC200 03 30 2011 Sources of Water Quality Impairment Urban Suburban Sprawl Population growth Airborne Pollutants Deforestation sediment problem Agriculture agriculture 30 30 30 How much nitrogen comes from the urban sprawl airborne pollutants and Population Growth Urban Suburban Sprawl Direct Point Source o Wastewater Treatment Facilities 3 1 pounds of Nitrogen per person Improving wastewater nitrogen delivered loads at plants not as close to goal Improving phosphorus at plants as well closer to goal ban on phosphorus in laundry detergent Indirect o Septic 9 5 pounds Nitrogen per person o Stormwater Lawn and garden chemicals Per waste Sediment Road oils and salts Debris o Impervious Surfaces 1970 2000 Residential lot size increased by 60 1990 2000 Population 8 Impervious Surface 41 Increased variation in stream flow Increased streamside erosion Increased flooding Airborne Pollutants o Stationary sources Power plants N Mercury Toxins Large industry Toxins Toxins o Mobile sources Cars trucks buses Trains Airplanes Small machines lawn mowers etc Small industry dry cleaners gas stations etc Agriculture Sources Ammonia o Fertilizer Run off from storms and irrigation N P Leaching N Some ammonia volatization N Run off from storms and irrigation o Sediment o Manure Creation Storage Use Storage o Animal Manures Poultry Litter Run off from storms and irrigation N P Leaching N Ammonia volatization N Land application as a crop nutrient Run off from storms and irrigaton N P Leaching N Ammonia volatization N Deforestation o 1982 1997 Lost 750 000 Acres 100 Acres day Predominantly for development Less absorption of air and surface pollutants Ecosystem services Shoreline cleaning erosion AREC200 03 30 2011 Positive Economics Descriptive Normative Economics Best outcome Value judgments Efficiency Time Equity Human behavior services Choices Constraints Consumer Demand How do our consumption decisions reflect value of goods and Input Derived Demand Demand for consumer goods creates demand for inputs into the production process AREC200 Policy Outcomes 03 30 2011 Pareto improvement A change in conditions policy allocation of resources etc that leave some groups better off and all other groups at least as well off as they were before the change Pareto efficient No additional change can be made that is a Pareto improvement Kaldor Hicks Compensation Principle Some groups individiduals are made worse off losers and some are made better off winners But the amount that the winners gain is more than