241 Environmental Geoscience (Posters)

Wednesday, 12 October 2011
9:00 AM - 6:00 PM
Hall C

NUTRIENT BUDGET FOR PIERMONT MARSH: RESULTS FROM INITIAL SAMPLING

Paper number: 241-11
Program: Technical Sessions
Time: 9:00 AM – 6:00 PM

Authors

Abstract

Piermont Marsh is a brackish Hudson Valley marsh 15 kilometers north of New York City. The marsh is principally drained through 4 outlets. Sparkill Creek is a freshwater stream draining the surrounding highlands constitutes the northern boundary. Two tidally driven creeks transect the Marsh from West to East: the Crumkill and an unnamed creek we have dubbed the “Tidal”. Ludlow Ditch, a no-longer-maintained drainage channel grading gently from the northern part of the marsh to the South terminates in a wide tidal outlet that is its southern boundary. Human influence in the marsh’s surrounding area has had profound effects, one of the most fundamental of which has been the shift from native grass species, predominantly Spartina alterniflora, to an invasive genotype of common reed, Phragmites australis. Along with this shift there have been changes in the root bed, the effective marsh interior and berm heights, the hydroperiod and, as a result, the ability of the Marsh to be utilized by various types of Hudson estuary fish.

We present nutrient data collected as one component of a broad ecological and geochemical study of the Marsh and its adaptation to human influence. The data have been collected during 2010 and 2011 from a set of stations positioned to capture fluxes between the marsh and the estuary at all major outflows. Net tidal cycle fluxes and fluxes resulting from runoff events are presented. Deviations from Redfield ratios and limiting nutrients are analyzed; Piermont Marsh data is compared to prior studies of the other three NOAA-managed reference marshes in the Hudson Valley. The data supplements carbon content data (presented in a companion poster) to estimate the carbon cycling and sequestration capacity of the Marsh sediments.

All data were collected and analyzed as part of Lamont-Doherty Secondary School Field Research Program, which engages NYC high school teachers and students in research in the Hudson/Raritan estuarine environment.