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Introduction to Wildlife & Fisheries Conservation WFSC 304 Lecture 17: Ecological Restoration Water and vegetation are key to most remediation. Veg stabilizes sediments, forms pathways for water into soil, adds organic matter to soil and thereby establishes habitat for a larger array of soil organisms. Let the positive synergy begin and be sustained. When it is disrupted (left) it must be reset by a long process of succession, or with help from humans with thumbs. Restoration Ecology “The process of assisting recovery of an ecosystem that has been degraded, damaged, or destroyed.” —Society for Ecological Restoration • Draws upon all major disciplines in the natural sciences • Ecosystems • Landscape ecology • Geomorphology • Hydrology • Soil science • Geochemistry • Animal behavior • Theoretical ecology • Population biology • Invasion biology • Evolutionary ecology Role of Restoration Ecology in Conservation Opportunity to conduct experiments Community assembly dynamics Secondary succession Fire dynamics Role of keystone species Alternative to in situ conservation Restoration and conservation are complementary for ecosystem protection Active restoration speeds the process of ecological renewal. The act of restoration requires keen naturalist perspectives, academic breadth, and experimentation. Steps to Designing and Implementing ER Site assessment – Examine and define preexisting conditions Setting goals (e.g. historic state, particular functions) Develop a restoration design or plan Obtain necessary permits Implementation of the designs Monitoring the restored system Adaptive management-iterative process Degradation brings an ecosystem through states that are progressively less functional (1-4; like cancer stages). Ecosystems commonly pass through state transitions during which recovery requires greater levels of intervention. In a slightly degraded site, recovery requires minimal intervention, but after the threshold is crossed (between 1 and 2), manipulations of vegetative structure and composition are necessary. If degradation is more severe, the second threshold is crossed (between 2 and 3) in which physical interventions like earthmoving or dyking are required to restore the site. Restored communities not always like original. Original is a good goal we have found not for sentimental but practical reasons. It is sustainable. Many restored systems are simplified and do not persist. As well, to restore ecosystem function we may often have to get used to the idea of “novel ecosystems”. The Great Lakes is a great example. It will never be historic, but the historic species have persisted. Ecosystem function is high again, though new predators and prey now rule. Major Case Study 1: Everglades Wetlands – Florida Everglades (maybe not so much with the “ever” part) Water is key to this restoration EVER GLADES NATIONAL PARK (link) “Spanning the southern tip of the Florida peninsula and most of Florida Bay, Everglades National Park is the only subtropical preserve in North America. It contains both temperate and tropical plant communities, including sawgrass prairies, mangrove and cypress swamps, pinelands, and hardwood hammocks, as well as marine and estuarine environments. The park is known for its rich bird life, particularly large wading birds, such as the roseate spoonbill, wood stork, great blue heron and a variety of egrets. It is also the only place in the world where alligators and crocodiles exist side by side. Everglades National Park has been designated a World Heritage Site, an International Biosphere Reserve, and a Wetland of International Importance.” Mosaic of freshwater ponds, prairies and forested uplands that support a remarkable volume and diversity of flora and fauna Historically 11,000 square miles of south Florida Historic water flow down the Kissimmee River into Lake Okeechobee, then south by sheet flow through the Everglades marsh to the flats of Florida Bay Sheet flow out of Okeechobee called the “River of Grass” for the vast expanse of sawgrass in the marsh The sheet flow spans as much as 60 miles in width, yet is only six inches deep in some places This wetland was degraded severely by water use and diversion for sugar plantations (strong lobby) and other agriculture 1905: Gov. Napoleon Bonaparte Broward began systematic effort to drain the Everglades for agriculture and development. Large tracts were transformed into farmland, and cities (Miami, Fort Lauderdale) sprang up and burgeoned. With increasing human habitation flood control in this essentially-stillwetland was needed. Fed to the rescue… In 1948, the U.S. Congress authorized the Central and South Florida Project , which created the largest water management system in the world. The project involved an extensive network of man-made canals, levees and water control structures that channel 1.7 billion gallons of water daily from the Everglades to the ocean. The direct water flow to the ocean does not get the filtration that would have occurred had it flown through the wetlands. The loss of water changed the natural characteristics of the marsh. Habitat loss was due to drying per se, but also to saltwater intrusions into the marsh from the ocean. Pollution entered from neighboring farms and cities. Changes in water quality stifled the growth of native plants, allowed exotic plants to take root and fueled the growth of algae which worsened the loss of natural habitat. As a result of this cycle continuing for so long the Everglades today is half the size of a century ago. Despite the damage that was done in the first half of the 20th century, the Everglades is still considered a national treasure just as extraordinary as the Grand Canyon, the Great Lakes or the Redwood Forests. A remarkable coalition of highly diverse and bipartisan interests has joined forces to make the restoration possible. To revive and protect this national treasure, Florida is undertaking the largest environmental ecosystem restoration in the world. It is Florida’s top priority to improve the quality of life for all south Floridians, provide adequate water supply for south Florida’s growing population and provide improved flood control, while preserving America’s Everglades and Florida’s Liquid Heart – Lake Okeechobee - and protecting natural wildlife and plants for future generations. 2000: State funding of the Everglades Restoration Investment Act to fund Florida’s 50 % (cost-share), complimenting Federal investment, to implement the Comprehensive Everglades Restoration Plan (CERP) FYI—for further interest, here is a well composed, thorough timeline arraying major events, esp. legislation and actions by Fed and State: http://www.dep.state.fl.us/evergladesforever/about/timeline.htm An economic analysis of the restoration problem, including ecosystem services is available here: http://www.evergladesfoundation.org/wpcontent/uploads/2012/04/Report-Measuring-Economic-Benefits-Exec-Summary.pdf How much is the project likely to cost and what is the benefit cost ratio? (Note CBS news suggests $20b has already been spent) Here, graphically, is the plan: INVASIVE SPECIES Miami is a port town—deals with imports of many exotics. Releases and escapes of exotics have plagued the Everglades. In some rivers all one may catch in a day would be (inedible) armored catfish Left: Non-natives impact native species. A dead 6’ American alligator burst forth from this 13’ Burmese python in Everglades National Park. Maybe the exotic snakes should stick to 5’ alligators. (ASSOCIATED PRESS/EVERGLADES NATIONAL PARK / October 5, 2005) Right: Natives fight back—water moccasin (cottonmouth) eating nonnative armored catfish. “… assorted characters of death and blight…” —? 20% of fisherman in south Florida target exotic species Good video here https://www.youtube.com/watch?v=x1n9tlESDeI (4 min) Case Study: Chesapeake Bay Largest of 130 estuaries in the US Estuaries are some of the most productive environments on the planet Support thousands (3,600 documented) of species of animals and plants Spawning and nursery grounds for 80-90 % of America's recreational fish catch and > 75 % of the commercial fish catch In bay fishing for oysters, crabs, fish, shrimp etc. Bay supports recreation Bay supports shipping (2 of the 5 largest N. Atlantic ports) 17 million people (over a billion kg of humans) drain into the bay The strain of nutrification and pollution reached a breaking point Now billions of dollars being spent in restoration projects Case Study: Guanacaste Dry Forest Degraded by heavy use of fires to maintain clear ranch and farm land • Fires kill trees and facilitate invasion by Hyparrhenia rufa, an invasive African grass • Goal – eliminate fires, restore dry forest ecosystem • Slow return of original species; reseeded by birds and bats • Replanting is costly and slow • Planting Gmelina, an exotic fast growing species, can speed reinvasion (only in areas where native trees were heavily degraded). • Used a Debt-for-Nature swap to purchase additional heavily degraded lands. • Negotiated with an adjacent orange plantation to swap pasture for forest and receive all of the discarded orange peels to use to recover heavily disturbed lands. “Restoration through compost!” Interesting concept: “Rewilding” Horses (sans tarpans) Cattle (sans aurochs) Red deer 56 km² outside Amsterdam “cute” The answers are not all technological. We tend to think of that first. But for most people that is not an appropriate or feasible solution. The Loess Plateau restoration is an example of what can be done by humans with thumbs http://vimeo.com/19661805