Date of Award

Winter 2006

Project Type


Program or Major

Natural Resources

Degree Name

Master of Science

First Advisor

Frederick T Short


The suitability of the seagrass deep edge as an indicator of water clarity was assessed by examining the sensitivity and specificity of this indicator to changes in light. Indicator specificity was assessed by examining the extent to which seasonal variation in environmental parameters affected the location of the deep edge at five eelgrass meadows in the Great Bay Estuary, New Hampshire. The mean location of the eelgrass deep edge was seasonally stable at three sites, confirming its suitability as an indicator. At two sites, the deep edge responded to long-term light reduction and changes in deep edge location of 1.3 meters were detectable between seasons. The recommended method of monitoring the deep edge is to measure deep edge location in reference to a permanent transect. The sensitivity of eelgrass growing along a depth gradient to a reduction in light was examined through a literature review and an experimental design.