Synopsis: Restoration methods of wetlands are not one size fits all. Jimmy Webb, Conservation Biology (BIOL 834), Spring 2011
Wetlands are a vital ecosystem. Wetlands support great biological diversity of species (Russell et al. 2002 and Liner et al. 2008). Even though wetlands contain great diversity, wetlands are often undervalued and overlooked (Russell et al. 2002). Scientists have estimated that approximately 50% of all wetlands have been lost since the colonization on the United States (Lehtinen and Galatowitsch 2001). There has been an estimated loss of 84% of wetlands in the southern states alone over the last 30 years (Russel et al. 2002). Efforts to restore these lost wetlands and the native species that inhabit them continues (Lehtinen and Galatowitsch 2001). These restoration efforts have been evaluated and many deemed unsuccessful for a number of reasons. Hilderbrand et al. (2005) outline some of the methods used to restore wetlands and the short comings of each of these approaches. The methods utilized to restore wetlands in a given area are not a one size fits all as it relates to future successes.
Humans inevitably have an impact on any ecosystem they come in contact with. With this in mind, one must manage ecosystems based on the effect that human inflict (Hilderbrand et al. 2005). Hilderbrand et al. (2005) states that conservation of ecosystems after degradation is not enough. For example, “No Net Loss” policy for U.S wetlands have not been effective since losses still exceed gains or are not functionally equal (Dahl and Alford 1996, Zedler 2000a). Attempts to limit further losses of wetlands have failed since wetlands are still disappearing at an alarming rate in spite of the “No Net Loss” policy. Also, the “No Net Loss” policy implies that wetland restoration will be equivalent to the pre-degradation wetland. In reality very few restored wetlands have achieved equivalency to existing wetlands (Zedler and Callaway 1999, , Cambell et al. 2002, Seabloom and van der Valk 2003). Also, methods in place for restoration and creation of wetlands are not successful in structure or function when compared to historical record. (Lockwood and Pimm 1999, Cambell et al. 2002, Zedler and Callaway 1999). Hilderbrand et al. (2005) indicates that scientists tend to attempt to recreate complex systems through simplified techniques and principles. Restoration efforts of wetlands are misguided by trying to accomplish in years what might take decades (Hilderbrand et al. 2005). Carbon Copy Approach
The Carbon Copy approach set the goal of restoring or creating a wetland that is a copy of the previous wetland or mimics a similar wetland elsewhere (Hilderbrand et al. 2005). Degradation of a wetland has occurred and the goal is to return the wetland to its pre-existing condition. There are problems which occur during secondary succession (Zedler 2000b). For example, as degradation continued the ecosystem went through succession of species (i.e., plants and animals). It may be difficult, if not impossible, to return it to the pre-existing state due to these changes (Hilderbrand et al. 2005). A system may be too degraded to return the wetland back to its desired historical states as noted by Hobbs and Norton (1996). Also the invasion of non-native species impacts the ability of returning the wetland to the historical state. Also changes may be limiting in the return to pristine conditions. Urbanization, dams, water changes (i.e. level, acidification, hydrology, etc) have altered the landscape thus the success of restoration (Ehrenfeld 2000). Most wetland restoration efforts have failed to restore wetlands to the same structure and function as it was historically or to that of a reference wetland (Zedler and Callaway 1999, National Research Council 2001, Seabloom and van der Valk 2003). The goal of returning the wetland to the desired historical state is likely...
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