Location, location, mitigation

Posted on March 26, 2010

To mitigate the impacts of development activities on natural wetlands, additional wetlands are often created.   Although the aim of wetland construction is to encourage the water regimes, soil conditions and vegetation typical of natural wetlands, more monitoring studies are needed to assess how well this work succeeds in restoring ecological function.  By measuring an array of hydrogeomorphic variables, Pennsylvanian researchers compared the structure and functional capacity of established (12 year old) created wetlands, new (1 year old) created wetlands, and natural reference wetlands.  The reference wetlands scored highest for a number of attributes, including  microtopographic variation, depth to water, soil organic content,  vegetative biomass, energy dissipation and short-term surface water storage.  Even after 12 years of development, created wetlands had relatively low scores for ecological function.  The results stress the importance of placing wetlands in appropriate environmental settings.

Reference: Hoeltje, S.M. & Cole, C. A.   2009.   Comparison of function of created wetlands of two age classes in Central Pennsylvania.  Environmental Management 43, 597–608.