TITLE:
Recent Trends of Zostera marina (Eelgrass) in a Highly Eutrophic Coastal Lagoon in the Mid-Atlantic Region (USA)
AUTHORS:
Michael J. Kennish, Gregg P. Sakowicz, Benjamin Fertig
KEYWORDS:
Barnegat Bay-Little Egg Harbor Estuary, Coastal Lagoon, Nutrient Enrichment, Eutrophication, Zostera marina Characteristics, Nutrient Reduction Regulation
JOURNAL NAME:
Open Journal of Ecology,
Vol.6 No.5,
April
22,
2016
ABSTRACT: Spatial
and temporal characteristics of Zostera
marina (eelgrass) in the Barnegat Bay-Little Egg Harbor Estuary are
compared before (2004-2011) and after (2012-2013) major fertilizer legislation
(Fertilizer Law A2290) was enacted in New Jersey (USA) to reduce nutrient
inputs from fertilizers to water bodies in the state. A significant decrease of Z. marina biomass and areal cover
occurred in this eutrophic estuary between 2004 and 2011 concomitantly with
increasing nitrogen and phosphorus loading from the watershed. The rate of
decline in aboveground and belowground biomass was significantly sharper during
2004-2006 than during 2008-2010. In 2010, Z.
marina biomass dropped to a very low level (mean aboveground biomass = 7.7
g dry wt mDŽ mean belowground biomass = 27.0 g dry wt mDŽ),
persisting through the last sampling period (October-November) in 2013. Biomass
and areal cover of Z. marina decreased even further after Fertilizer Law A2290 was enacted in January 2012,
with the lowest values recorded from August to November each year. These low
values are the result of ongoing eutrophication of the system. More seagrass
monitoring and research are necessary in future years to determine if the
fertilizer law will have a positive effect on Z. marina condition in the estuary over the long term.