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Professor Ivan Valiela of the Boston University Marine Program (BUMP) at the Marine Biological Laboratory in Woods Hole was OPET's Keynote Speaker at the Annual Meeting. Prof. Valiela has studied coastal ecology on Cape Cod for about 30 years. Recently, his students have used Oyster Pond as their "field laboratory."
Dr. Valiela pointed out that the problem of coastal pollution and eutrophication (blooms of growth of unwanted algae that destroy habitat for aquatic plants and animals) experienced here on Cape Cod are similar to those along much of the eastern seaboard of the US and elsewhere. About 50% of the population lives within 50 miles of shorelines. That population is rapidly increasing, leading to conversion of forested land for residential and commercial usage and also leading to increased sewage production.
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Prof. Valiela and his students have studied extensively several watersheds in the Waquoit Bay area, including some that are densely populated and some that are relatively undeveloped. These studies have shown that, in undeveloped areas, rainwater is the most important source of nitrogen (N) to the ecosystem. In contrast, septic tank effluent is by far the most important sourse of N to the estuary in watersheds that are thickly populated with houses. Runoff of lawn fertilizers is also a significant source of N, but less so than septic systems. Seagrass, which forms the best habitat for many common shellfish, disappears in estuaries where the nitrogen content is too high.
Oyster Pond, Valiela reported, is "in pretty good shape." The inputs of N to Oyster Pond are low relative to some of the more heavily populated areas of East Falmouth. Nevertheless, increased inputs of both nitrogen and phosphorus via septic systems and lawn fertilizers should be considered potential threats to the health of Oyster Pond as new homes are constructed within the watershed. A study conducted in October 2001 by a class project showed that both the algae and the fish in the pond have a form of nitrogen |
(specifically, the abundance of the 15N isotope) that is characteristic of being derived from human sewage. Therefore, although septic effluent has not yet caused severe or frequent algal blooms, the impact of human sewage on the cycling of nutrients in the pond is definitely detectable. Studying the role of sewage inputs to the health of the pond is the subject of further studies by Valiela's students.
Valiela's class also used Oyster Pond as their field laboratory in an intensive study carried out in September 2002. The students first met with area residents at the beginning of the month to hear their concerns and suggestions for topics of research. The students then presented with the results of their studies to a meeting of residents at the end of that month. This year's study further confirmed the importance of septic systems as the main source of N to the pond. The students also measured the amount of N present in the mass of submerged and floating vascular platns, which is probably where a lot of the N goes each summer. The students' reports for 2001 are already posted on OPET's website, and the 2002 reports will be posted soon. If this class is repeated in future years, participation of area residents in the pre- and post-study "stakeholders meetings" is highly encouraged and recommended. The students are very articulate and adept at explaining their work to a lay audience, making for an informative and entertaining evening. -- By Eric Davidson. . . |
politics since 1988, first serving as vice-chair on the Charter Committee, one of 9 elected to fulfill the mission of codifying the Town of Falmouth's form of government; later as vice-chair on he Charter Review Committee; and most recently as a member of the Planning Board, since being elected in May 2000. As if that isn't enough, Pat is also involved with her church, St. Joseph's of Woods Hole, where she taught confirmation classes for 9 years and is now chairman of the Pastoral Council. She somehow finds time to enjoy reading ("mostly mysteries"), gardening and cross-stitch, as well.
But Pat's real pride and joy are her two children (now adults) and three grandsons. Motherhood, she says, was "the most satisfying and challenging work of my life." The family is widespread now: son Christopher, who has a Ph.D., lives with his wife and three sons in California, where he oversees cancer drug trials; daughter Kerry is in upstate New York working at Cornell University, putting her degree in exercise physiology to good use in their wellness program. We hope Pat and Bill are not tempted to leave the area, however, as their expertise has been invaluable to OPET over the years. Thank you, Kerfoots!
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