The Hackensack River Estuary is a highly urbanized and complex tidal ecosystem in Northern New Jersey once known as one of the most polluted water courses in the United States. This legacy has significantly impaired the ecological function of some 8,300 acres of remaining tidal wetlands. The main factors driving this impairment are tide restricting structures, urbanization and industrialization that resulted in high levels of contaminates in the sediments, abundance of invasive species, habitat fragmentation, and alterations in the hydrology. This study measured physical and ecological impairments of seven wetlands to create an objective evaluation system to prioritize the sites for wetland acquisition, wetland preservation, wetland enhancement, and natural resources management.
Results/Conclusions
The study compared minimally impacted, degraded and ecologically enhanced wetlands to test the developed impairment metrics and compare the marshlands. Plant species composition and abundance including the presence of invasive species provided excellent indicators of habitat degradation. Micro-topography, vegetation patterns, as well as community and landscape level habitat fragmentation and connectivity contributed substantially to the assessment of levels of wetland impairment. According to the developed impairment metrics the enhancement site scored highest, followed by the minimally impacted wetlands and the degraded marshlands.