1 / 26

Clean-up of Boston Harbor

BENTHIC COMMUNITY STRUCTURE AND BIODIVERSITY FOLLOWING SEWAGE ABATEMENT PROGRAMS IN BOSTON HARBOR By James A. Blake, Nancy J. Maciolek ENSR Marine & Coastal Center, Woods Hole, MA & Kenneth Keay Massachusetts Water Resources Authority, Boston, MA. Clean-up of Boston Harbor.

lona
Download Presentation

Clean-up of Boston Harbor

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BENTHIC COMMUNITY STRUCTURE AND BIODIVERSITY FOLLOWING SEWAGE ABATEMENT PROGRAMS IN BOSTON HARBOR ByJames A. Blake, Nancy J. Maciolek ENSR Marine & Coastal Center, Woods Hole, MA&Kenneth KeayMassachusetts Water Resources Authority, Boston, MA

  2. Clean-up of Boston Harbor • End Sludge disposal (1991) • Development of New Sewage Treatment Facilities and offshore outfall • Upgrade Sewage to Secondary Treatment (1997–2000) • Transfer Sewage Outfalls from Boston Harbor To Massachusetts Bay (September 2000) • On-going CSO improvement program

  3. Benthic Community Monitoring in Boston Harbor • Surveys performed for the MDC as part of the 301(h) Waiver Applications: 1978, 1979, 1982 • Formal Monitoring by MWRA began in September 1991 • April and August Sampling from 1992−2002 • August Sampling continued since 2003 • Total of 17 Years of Benthic Monitoring: August/September 1991−2007 and continuing

  4. Nitrogen Loading and Sewage Abatement in Boston Harbor (after Taylor, 2006)

  5. Benthic Sampling Stations in Boston Harbor1991−2007 T01: Deer Island Flats T02: Governor’s Island Flats T03: Long Island T04: Dorchester Bay T05A: President Roads T06: Peddocks Island T07: Quincy Bay T08: Hingham Bay C019: Inner Harbor CSO

  6. Deployment of the Ted Young grab sampler 0.04-m2 surface area

  7. Looking for Evidence of Change • Changes in Faunal Abundance (density of organisms) • Changes in Species Richness (numbers of species) • Changes in Species Composition (i.e., opportunistic or stress-resistant species replaced by others) • Changes in Species Assemblages (community structure; functional groups) • Changes in Species Diversity (H′, ESn, Log-series alpha)

  8. Changes in Faunal Abundance

  9. Long-term Trends in Species Richness

  10. Long-term Trends in Species Diversity: alpha

  11. Benthic parameters summarized by time periods defined by Taylor (2006)

  12. Changes to Boston Harbor Benthos in 2005 Amphipod mats entirely absent in 2005 Shifted from a biologically to physically dominated sediment surface

  13. Ampelisca Abundance: 1991–2007

  14. Some benthic invertebrates in Boston Harbor

  15. Nephtys cornuta Adults

  16. Nephtys cornuta larvae

  17. Amphipod Population Crash in 2005 • Loss of habitat diversity • Commensurate decline in species richness and diversity in 2005 and 2006 • Populations stayed low in 2006, but slight recovery is evident in 2007 • Long-term reduction in organic loadings • Two unusual spring 2005 Nor’easters contributed to amphipod population crash • Over-wintering adults swim into the water column in the spring and the storms are believed to have caught these individuals and swept them away

  18. Long-Term Results for Individual Stations 1991−2007 T01 Deer Island Flats: significant improvement in species diversity and complete change in community structure

  19. Total Abundance at Station T01 (1991−2005)

  20. Diversity (log-series alpha) at Station T01 (1991−2006)

  21. PCA-H analysis of T01: 1991–2007

  22. Euclidean Distance BiplotStation T01 Deer Island Flats(1991–2007)

  23. Overall Conclusions Relative to Sewage Diversion from Boston Harbor to Massachusetts Bay • Benthic communities in Boston Harbor have improved significantly since the diversion to the new outfall in September 2000 • There is no evidence of any adverse impact on the infaunal benthos of Massachusetts Bay or Cape Cod Bay since the new outfall came on-line

  24. Acknowledgements Massachusetts Water Resources Authority is thanked for supporting this long-term monitoring program and leading the effort to clean up Boston Harbor Field programs were successfully led by Isabelle P. Williams & Pamela Neubert Laboratory analyses were managed by Isabelle Williams and Stacy Doner; important taxonomic contributions have been made by Brigitte Hilbig, Russ Winchell, Gene Ruff, Tim Morris, & Nancy Mountford Interpretation has been enhanced by contributions from Bob Diaz, Don Rhoads, Gene Gallagher & Roy Kropp

More Related