NASA/GISS and LDEO-Shift in Plant Communities and Organic Matter in the lower Hudson Estuary and Meadowlands since European Impact

Abstract: A transect of marsh cores from Jamaica Bay northward provides acrchives of vegetation history, climate change, and human impact. Community disturbaance of the forests and landscape is indicated by pollen and spore stratigraphy at time of European settlement up to present, with large losses of forest. Forests prior to European impact were comprised of more Pinus strobus, Quecus, Tsuga canadensis, and Carya than today. A 3.7 m sediment core from Meadowlands shows pollen signature is dominated by sedges and grasses, while Hudson Marshes are dominated by oak and pine. This difference is probably due to the large spatial extent of the Meadowlands marshes. Primeval Meadowlandss sedge communities were Primarily composed of Scirpus and Cyperus though Cladium and Eleocharis were also present. Local marsh community composition has changed greatly both prior to European arrival and since European impact. Phragmites and Typha angustifolia have increaded greatly since the 1600’s. Percent of organic matter in the HUdson marshes since European impact increase by a factor of five, probably caused by the sharp decline in upland inorganics. Reasons include dams built first by the Dutch settlers for millponds. Meadowlands organic matter percent delines with European impact, probably due to influx of inorganic matter from regional disturbabnces.