title: Dependence of eelgrass (Zostera marina) light requirements on sediment organic matter in Massachusetts coastal bays: implications for remediation and restoration.
abstract: Using a calibrated bio-optical model we determined that the optical water quality conditions in several nitrogen-impaired embayments and in one unimpaired system were within the range of values known to support eelgrass growth. We also used the model to identify a range of light requirements for eelgrass (Zostera marina). Higher eelgrass light requirements, expressed as a percentage of surface-incident irradiance, corresponded with higher sediment organic matter content. These results corroborated findings by previous studies which indicate a generalized relationship: seagrasses growing in turbid conditions with poorer water and sediment quality have higher light requirements than those growing in less degraded conditions. The mechanistic reason for the variation in light requirements is still not completely explained and cannot be attributed to a single independent variable. Varying light requirement have important implications for eelgrass protection and should be considered when setting restoration targets for eelgrass in water quality and nitrogen remediation programs.
authors.affiliation: Center for Coastal Fisheries and Habitat Research, NCCOS, NOS, NOAA, 101 Pivers Island Rd, Beaufort, NC 28516, USA. Electronic address: jud.kenworthy@gmail.com.
authors.forename: W J
authors.initials: WJ
authors.lastname: Kenworthy
authors.affiliation: Smithsonian Environmental Research Center, P.O. Box 28, Edgewater, MD 21037, USA. Electronic address: gallegosc@si.edu.
authors.forename: C L
authors.initials: CL
authors.lastname: Gallegos
authors.affiliation: Division of Watershed Management, Massachusetts Department of Environmental Protection, 1 Winter Street, Boston, MA 02108, USA. Electronic address: charles.costello@state.ma.us.
authors.forename: Charles
authors.initials: C
authors.lastname: Costello
authors.affiliation: Center for Coastal Fisheries and Habitat Research, NCCOS, NOS, NOAA, 101 Pivers Island Rd, Beaufort, NC 28516, USA. Electronic address: don.field@noaa.gov.
authors.forename: Donald
authors.initials: D
authors.lastname: Field
authors.affiliation: Center for Coastal Fisheries and Habitat Research, NCCOS, NOS, NOAA, 101 Pivers Island Rd, Beaufort, NC 28516, USA. Electronic address: Giuseppe.dicarlo@gmail.com.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: di Carlo
mesh_terms: D061006:Bays; D052918:Environmental Restoration and Remediation; D019015:Geologic Sediments / Q000032:analysis*; D008027:Light; D008404:Massachusetts; D009584:Nitrogen / Q000032:analysis; D035962:Zosteraceae / Q000254:growth & development / Q000502:physiology*
chemical_list: D009584:Nitrogen
keywords: Eelgrass; Light requirements; Massachusetts; Nitrogen loading; USA; Water quality; Zostera marina