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Ecological Restoration. Image from Wikipedia. Ecological Restoration. George Perkins Marsh (1801 – 1882). Man & Nature (1864) Contemporaneous with Romantic-Transcendalists ( e.g. , Emerson, Muir, Thoreau). Marsh’s “ key insight ” – anthropogenic imbalances in Nature
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Ecological Restoration Image from Wikipedia
Ecological Restoration George Perkins Marsh (1801 – 1882) Man & Nature (1864) Contemporaneous with Romantic-Transcendalists (e.g., Emerson, Muir, Thoreau) Marsh’s “key insight” – anthropogenic imbalances in Nature “did not correct themselves automatically… Humans had to restore what humans had disturbed.” Photo of Marsh (U.S. diplomat & philologist) from Wikimedia Commons; Quote from S. Kingsland (2005)
Ecological Restoration Aldo Leopold(1887 – 1948) A Sand County Almanac (1949) Milestone for plant community restoration – Leopold & colleagues restored ~120 ha of forest & prairie at U. Wisconsin Arboretum; 1930s Photo from Oregon State University
Ecological Restoration Jared Diamond (b. 1937) Collapse (2005) Human history is replete with examples of over-exploitation & habitat destruction without restoration that resulted in societal collapse (i.e., societies that were not operating sustainably) Photo of Diamond from Wikimedia Commons; image of book jacket from amazon.com
Ecological Restoration Jared Diamond (b. 1937) Collapse (2005) Final paragraph of Collapse: “My remaining cause for hope… we have the opportunity to learn from the mistakes of distant peoples and past peoples. That’s an opportunity that no past society enjoyed to such a degree…” Photo of Diamond from Wikimedia Commons; image of book jacket from amazon.com
Ecological Restoration “…the process of intentionally altering a site to establish a defined, indigenous, historic ecosystem. The goal of the process is to emulate the structure, function, diversity and dynamics of the specified ecosystem…” (Society for Ecological Restoration 1991) Crissy Field, San FranciscoBefore restoration Crissy Field, San FranciscoAfter restoration Photos of a restoration success story from Wikimedia Commons
Ecological Restoration Groom et al. (2006) recognize several sub-categories: Rehabilitation – improves a site from its degraded state Enhancement or augmentation – improves a few ecosystem functions in a site from its degraded state Reclamation – often associated with mines or waste dumps, in which the initial goal is detoxification & terrain stabilization Replacement – specifies a novel community type for the site to achieve a particular conservation goal; often to improve ecosystem processes with less regard for ecosystem structure
Ecological Restoration Trajectories of restoration projects Ecosystem processes ORIGINAL ECOSYSTEM Replacement Restoration Replacement Rehabilitation Enhancement Biomass & nutrient cycling No action? DEGRADED ECOSYSTEM No action? Ecosystem structure Species & complexity Modified from Fig. 15.1 in Groom et al. (2006)
Ecological Restoration Additional sub-categories from Groom et al. (2006) & other texts: Remediation (similar to reclamation) – removes chemical contaminants from polluted areas – by biotic, chemical or physical means – especially to protect human & ecosystem health Re-creation (similar to replacement) – constructs a new biological community on a site in which anthropogenic disturbance essentially removed the entire native community, often in an attempt to match a particular historic condition
Ecological Restoration U. S. Legislation – e.g., Clean Water Act (1972) “to restore & maintain the chemical, physical & biological integrity of the Nation’s [surface] waters” Requires mitigation: if unavoidable impacts to waters & wetlands occur, those responsible must restore / re-create comparable ecosystems elsewhere Photo of wetland mitigation project in Australia (outside jurisdiction of CWA) from Wikimedia Commons
Ecological Restoration U. S. Legislation – e.g., Surface Mining Control & Reclamation Act (1977) Aims to prevent adverse effects of surface mining (especially coal) & requires mining companies to restore mined sites (usually initiated through reclamation) Photo of coal strip mine in Wyoming from Wikimedia Commons
Ex situ breeding reintroduction Whooping Crane (Grus americana) The tallest bird species in N. America; one of the most endangered (41 wild birds in 1941; ~350 today) Photo from Wikimedia Commons
Ex situ breeding reintroduction Whooping Crane (Grus americana) Cross-fostering with Sandhill Cranes failed, due to imprinting on foster parents (which resulted in inappropriate mate choices later) Captive breeding, followed by migratory training using light aircraft, has re-established an eastern migratory population (Wisconsin–Florida) Photo from Wikimedia Commons
Translocation Wolves (Canis lupus) in Yellowstone Photo of translocation of wolves from Alberta, Canada to Yellowstone, Jan. 1995, from Wikimedia Commons
Translocation Wolves (Canis lupus) in Yellowstone Photo of Alberta wolf in acclimation pen in Yellowstone, Jan. 1995, from Wikimedia Commons
Translocation Wolves (Canis lupus) in Yellowstone Photo of translocated Alberta wolf in Yellowstone, from Wikimedia Commons
“Restoring Yellowstone’s Aspen with Wolves” Photo from Wikimedia Commons; Figure from W. J. Ripple & R. L. Beschta (2007) Biological Conservation
“Restoring Yellowstone’s Aspen with Wolves” “combined effects of a behaviorally- mediated and density-mediated trophic cascade” Density-mediated – indirect carnivore effect on plants owing to lethal direct carnivore effect on herbivore density Behaviorally-mediated – indirect carnivore effect on plants owing to non-lethal carnivore effect on herbivore behavior Figure & quote from W. J. Ripple & R. L. Beschta (2007) Biological Conservation
Re-wilding North America with Pleistocene Megafauna Some Conservation Biologists have made a serious proposal that we should re-create the N. Am. Pleistocene fauna with modern analogs e.g., African elephants, South American camelids… Artist’s re-creation of North American Pleistocene fauna from Wikimedia Commons
Re-wilding North America with Pleistocene Megafauna … and carnivores, such as African lions & Siberian tigers (modern analogs of Smilodon [Saber-toothed cat]) It’s a serious proposal, but is it a good idea? Skull & artist’s re-creation of Smilodon from Wikimedia Commons
Key ecological goals for restoration 1. Restore natural ecosystem processes 2. Re-establish native species and their functional roles (especially key players, e.g., ecosystem engineers, foundation species, etc.) 3. Remove / control / monitor exotic species 4. Others?
“Seabird Islands Take Mere Decades to Recover Following Rat Eradication” Photo of New Zealand seabird colony from Wikimedia Commons
“Seabird Islands Take Mere Decades to Recover Following Rat Eradication” 15 islands off NE coast of New Zealand Black dashed lines = Control islands (never invaded by rats) Red dashed lines = Positive Control islands (rats currently present) Figure from H. P. Jones [Ph.D. 2010 Yale School of Forestry & Environ. Sci.] (2010) Ecological Applications
“Seabird Islands Take Mere Decades to Recover Following Rat Eradication” “I show that soil, plant, and spider marine-derived nitrogen levels and C:N ratios take mere decades to recover even after centuries-long rat invasion. Moreover, active seabird restoration could speed recovery even further, giving much hope to quickly conserve many endemic species on islands worldwide.” Quote from H. P. Jones [Ph.D. 2010 Yale School of Forestry & Environ. Sci.] (2010) Ecological Applications
“Rapid Recovery of Damaged Ecosystems” Meta-analysis 240 published studies Figure from H. P. Jones [Ph.D. 2010 Yale School of Forestry & Environ. Sci.] & O. J. Schmitz (2009) PLoS ONE
“Rapid Recovery of Damaged Ecosystems” Meta-analysis Figure from H. P. Jones [Ph.D. 2010 Yale School of Forestry & Environ. Sci.] & O. J. Schmitz (2009) PLoS ONE
“Rapid Recovery of Damaged Ecosystems” Meta-analysis “We provide startling evidence that most ecosystems globally can, given human will, recover from very major perturbations [a.k.a. disturbances] on timescales of decades to half-centuries.” “The message of our paper is that recovery is possible and can be rapid for many ecosystems, giving much hope for humankind to transition to sustainable management of global ecosystems.” Quotes from H. P. Jones [Ph.D. 2010 Yale School of Forestry & Environ. Sci.] & O. J. Schmitz (2009) PLoS ONE
“The Rise of Restoration Ecology” Cover of Science – July 31, 2009
“Enhancement of Biodiversity & Ecosystem Services by Ecological Restoration” Meta-analysis (89 restoration assessments; response ratio = ln[Restored / Degraded or Reference]) Provisioning = e.g., fish, food crops, timber Supporting = e.g., nutrient cycling, primary production Regulating = e.g., climate, water supply, soil characteristics Figure & quote from J. M. Rey Benayas et al. (2009) Science
“Enhancement of Biodiversity & Ecosystem Services by Ecological Restoration” Meta-analysis (89 restoration assessments; response ratio = ln[Restored / Degraded or Reference]) “Ecological restoration increased provision of biodiversity and ecosystem services by 44 and 25%, respectively. However, values of both remained lower in restored versus intact reference ecosystems.” Figure & quote from J. M. Rey Benayas et al. (2009) Science
Ecological Restoration Image from www.portlandonline.com