Accounting for Wetland Loss: Wetland Mitigation Trends in Northeast Florida 2006–2013
Abstract
The realization of wetland ‘no net loss’ policy under Section 404 of the Clean Water Act remains uncertain, as mitigation practices force a trade-off in on-site mitigation with loss of biological integrity and off-site mitigation with a redistribution of ecosystem services. Wetlands cover 25 % of the Lower St. Johns River Basin (LSJRB), northeastern Florida, a region impacted by urban development. This case study investigated whether impacted wetland area and type of mitigation differ with land use intensity among the years 2006–2013 from a review of 522 Environmental Resource Permits. A Landscape Development Intensity index was used to compare land use as a function of anthropogenic activity for permitted parcels and mitigation banks. Forested wetlands comprised 47–97 % of impacted wetland area/yr and the majority of parcels and mitigation banks were in mid to high development areas (75 % of area). On-site only mitigation (29 % of permits) and use of mitigation banks (27 %) were more common than off-site only mitigation (20 %). Wetland preservation (880 ha/yr) was more common than wetland creation (9 ha/yr). This study puts into question the ‘no net loss’ wetland policy as urban development contributes to cumulative loss, fragmentation, and re-organization of wetlands across the landscape despite compulsory mitigation.