Field Verification Program (Aquatic Disposal). The Assessment of Black Rock Harbor Dredged Material Impacts on Laboratory Population Responses.
Abstract
Studies were conducted to determine the applicability of using population responses to assess the impact of dredged material. Laboratory methods were successfully developed to continuously expose Ampelisca abdita and Mysidopsis bahia to bedded and suspended sediments throughout their life cycle. Biological effects, including survival, individual growth, reproduction, and intrinsic rate of population growth, were measured over a range of exposures to Black Rock Harbor dredged material (BRH). Short-term effects (96-hr LC50) were observed at BRH suspended sediment concentrations of 262 mg/1 and 80 mg/1 for M. bahia and A. abdita, respectively, while the 10-day LC50 for A. abdita was 10.5 mg BRH/1. Thus, A. abdita was three times more sensitive to the acute effects of BRH sediment than M. bahia. Acute toxicity in A. abdita was strongly time dependent with 10-day exposures showing an eightfold increase in toxicity compared to the 4-day toxicity data. This may be the result of A. abdita's more intimate contact with the contaminated sediments. This study demonstrates that chronic responses are the best predictors of environmental impacts.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1987
- Accession Number
- ADA184569
Entities
People
- John H. Gentile
- K. J. Scott
- Michele S. Redmond
- Suzanne M. Lussier