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The Everglades. Environmental Science Dr. Peggy Green. • Flat, extends over large area with diverse ecosystems • Water dominated, low nutrient system • Fluctuating water levels and periodic fires. What free services are provided by the Everglades Ecosystem?.
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The Everglades Environmental Science Dr. Peggy Green
• Flat, extends over large area with diverse ecosystems • Water dominated, low nutrient system • Fluctuating water levels and periodic fires
What free services are provided by the Everglades Ecosystem? • Rich biodiversity contributes to stability • Coastal communities serve as nursery & breeding grounds for marine species • Coastal communities buffer against damage from storms & tidal surge • Serves as oxygen and food factory • Purifies water • Water storage / flood protection
The Everglades of the Past Kissimmee R. Basin Lake Okeechobee
“Heart of the Everglades” in S. Florida: Ridge and Slough Topography • Small differences in elevation make big differences in vegatative cover, thus the “habitat” of the area
Florida Bay Estuary • Florida Bay is the shallow body of water between the southern edge of the state and the FL Keys Florida Bay contains many mangrove islands Average depth is just 3 ft!
Today’s Everglades has been vastly altered by building canals, pumping stations, and dikes to allow drainage of vast areas for human development.
Channelization of the Kissimmee River • ~14,000 ha of floodplain wetlands destroyed • Beef, dairy, & agricul- ture have moved in • Water is impounded so flowing river has been converted to stagnant pools
Lake Okeechobee Used As a Reservoir • Lake Okeechobee was diked and turned into a reservoir • Eliminated much of the lake’s wetlands • Runoff from agricultural lands has degraded water quality Algal bloom due to nutrient overload
Everglades Drained - only 50% Remains • The eastern portion of the Everglades has been drained for cities • The northern portion is drained for agriculture • The central portion is WCAs • The southern portion is protected as ENP • Water impounded, no flow among wetlands
Water redirected to meet the needs of the human population Channelized flow:Fresh water must constantly be pumped out into the estuaries to keep developed areas from flooding.
Florida Bay Important feeding area for manatees and turtles Deteriorating water quality and impacts from boating, pollution & growing human population are destroying habitat and endangering fisheries.
Major Environmental Problems • The dredging, diking, and ditching of South Florida has given us dry land, flood protection, and drinking water for present needs • It has also given us: • Contaminated water • Water shortages • Soil subsidence • Spread of exotic invasive plants & animals • Habitats that are forever lost / fragmentation of remaining habitats • Dying coral reefs
1. Poor Water Quality • Florida is the 2nd largest dairy state after Wisconsin – can you say “manure” (solutions?) • Fertilizer used in the EAA & in maintaining urban landscapes creates high phosphorous levels (causes spread of cattails & algal blooms) • The EAA uses tons of pesticides each year, some of which were • banned in the 1970’s • but still show up in water • Florida Bay is becoming too • salty due to limited freshwater flows from the ENP
Mercury levels are very high in many predators in South Florida • This map shows mercury levels in large mouth bass • Limits on fish consumption are posted by the State
• Overuse of the water resources has resulted in salt water intrusion -- one result of a population that exceeds the carrying capacity of the ecosystem.
2.Water Shortages 1.7 billion gallons of water sent to tide each day (on average) overwhelming estuaries with fresh water “pulses” Yet, we end up with water restrictions and shortages
3. Soil Loss: Where has all the soil gone? • The EAA has lost more than 5 ft of soil in most areas • Loss is estimated at 1 in. per year • This changes topography and removes pressure on water to flow south • Minerals concentrated in remaining soil, causing release in runoff.
4. Spread of Invasive Exotic Species • Over 1.5 million acres of land are dominated by exotic plant species • There are many exotic animals, but we know very little about them
due to construction of roads, canals, cities, & farms and pollution generated by activities of the growing human population 5. Fragmentation & Deterioration of Habitats
Pressure for Continued Development Recent economic downturn has slowed down the growth rate.
Why should we care? • If we don’t fix this system, things will only get worse: more pollution, less clean water, etc. = lower quality of life and increased cost of living • Most importantly to those interested in sustainability, we must return this system to a more natural state to ensure the proper functioning of the ecosystem and restore its ecological services to maintain the web of life for future generations as well as current residents.
Summary: To allow for population growth, a system was built that drained much of the wetland and changed water distribution, timing, quantity, and quality in the Everglades.
How are we going to save this system? • Two major projects are addressing the environmental problems we face: • The Kissimmee River Restoration Project is attempting to restore some of the floodplain to the K.R. and restore more natural flows • The Comprehensive Everglades Restoration Plan (CERP) is addressing the problems in the ecosystem from Lake Okeechobee to Florida Bay
Kissimmee River Restoration Project A portion of the channelized Kissimmee River is being restored to original meandering course by backfilling the channel; 2 water control structures are being removed.
The CERP • The Comprehensive Everglades Restoration Plan is going to cost more than the original estimate of $8,000,000,000 • The plan is trying to meet the needs of the environment and supply water and flood protection to the residents of South Florida up to the year 2050 • Some of the projects have been delayed due to lack of promised federal funds, but recent appropriations have begun to move projects forward
There are a wide variety of projects planned for the entire system
Establish buffer zones around the Everglades • Create surface water storage reservoirs (purchase of land in EAA) • Build aquifer storage & recovery wells (controversial) • Build stormwater treatment areas (filter marshes) • Reuse wastewater • Manage seepage to prevent loss of groundwater and flooding • Remove barriers to the sheetflow of water (elevate Tamiami Trail) • Change the water delivery schedules to more closely mimic the natural system