Twelve-year mapping and change analysis of eelgrass (Zostera marina) areal abundance in Massachusetts (USA) identifies statewide declines.
Author(s): Costello, Charles W. and W. Judson Kenworthy.
NCCOS Center: CCFHR (http://ccfhr.noaa.gov)
Center Team: Beaufort
Publication Type: Journal Article
Journal Title: Estuaries and Coasts
Date of Publication: 2011
Reference Information: 34
Keywords: CCFHR, NOAA Oceans, Ecosystems, Estuaries, Seagrass, Distribution, Mapping, Change analysis, Declines, Water quality, Massachusetts
Abstract: Between 1994 and 2006 the areal distribution o f seagrasses in 47 of the 89 coastal embayments and portions of seven open water nearshore areas in Massachusetts were mapped with a combination of aerial photography, digital imagery and ground truth verification. In the open water areas 22,424 acres of seagrass were mapped, slightly more than twice the amount detected in the coastal embayments. A change analysis in 33 of the original 47 embayments showed declines in 30 locations representing all geographic regions of the state. Rates of decline ranged from 0.06%y-1 to as high as 8.39%y-1, averaging 3.25%y-1 and resulting in a 20% loss (1913 acres) of seagrass. Some embayments lost all their seagrass. The results affirm that previously reported losses were symptomatic of more widespread seagrass declines. In order to protect and restore seagrasses in Massachusetts, resource management agencies should continue; 1) statewide mapping efforts, 2) implementation of programs reducing stressors, 3) identifying priority embayments and municipalities for nutrient remediation and potential sites for seagrass recovery, and 4) implementing water quality and sediment monitoring and management programs for the conservation of seagrasses.
Location URL: http://www.ingentaconnect.com/content/klu/12237a/2011/00000034/00000002/00009371