PARENT SESSION
Symposium #16: Science and Practice of Setting Standards for Restoration Success.
Organized by: E Read, J Rieger, and K Kramer
Tuesday, August 6. 1:00 PM to 4:45 PM. Maricopa Meeting Room, TCC.
Assessing function of mitigated and natural wetlands.
Hatfield, Colleen*,1, Hartman, Jean Marie1, Mokos, Jennifer1, Kaplan, Marjorie2, 1 Rutgers University, New Brunswick, New Jersey2 New Jersey Department of Environmental Protection, Trenton, New Jersey
ABSTRACT- One of the basic tenets behind wetland mitigation programs is that loss of wetland acreage should not lead to net loss in wetland function. In many instances we do not know what wetland function is being lost nor do we know what wetland function is achieved with mitigation. The Wetland Mitigation Quality Assessment (WMQA) is a qualitative procedure that uses a suite of field indicators to evaluate the relative probability that a constructed wetland will develop into a natural wetland system and provide wetland function over time. Our specific interests in WMQA was to look at 1) how robust the method was; 2) to compare how the procedure assessed the actual function of natural wetlands and the potential function for mitigated wetlands and 3) observer variability in applying the procedure. Three teams independently evaluated a set of mitigated and emergent wetlands in central New Jersey. Sampling was repeated early and late in the growing season. In general, mitigated wetlands had lower scores than natural wetlands, suggesting that the potential for mitigated wetland function is lower than natural sites. Landscape position was the primary factor in lowering the WMQA score and the potential for wetland function for mitigated wetlands. WMQA was not significantly sensitive to seasonality or observer variability but caution is warranted when best professional judgment is used with any qualitative assessment methodology including WMQA.
KEY WORDS: mitigation, wetland, function, assessment