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Oneida Lake: ever-changing ecosystem
Managing water resources in Oneida Lake, WM Kappel
Oneida Lake watershed: A valuable diverse ecosystem, SM Harrington
Water level management, HM Goebel
Oneida Lake: undergoing ecological change, EL Mills, KT Holeck
Evolution of the Oneida Lake fishery, T VanDeValk, L Rudstam
Regional partnerships for Oneida Lake watershed, AB Saltman
Helping to protect Oneida Lake, J Henke
Trends: technology and management of municipal wastewater, D Interdonato, E McCarthy
Outstanding young researchers
President's message, D. Ellis
Executive director's message, P Cerro-Reehil
Winter 2001 — Vol. 31, No. 4 |
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Outstanding young researchers
A team of Swedish students has won the prestigious international water environment prize, a prize given to high school students for their research on water and the water environment. Abstracts of the team's work and that of the U.S. entrant are below.
The Prize was established in 1992 to engage and support the interest of young people in water environment issues. The Stockholm International Water Institute administers the Prize. The competition has been sponsored since 1997 by ITT Industries. WEF co-sponsors the Prize in the U.S. WEF member associations in Canada, Argentina, and Australia sponsor the Prize in their countries.
Sweden—Removal of metal ions from leachate
by Magnus Isacson, Johan Nilvebrant, Rasmus Öman
Waste deposits generate polluted water (leachate) which contains metal ions. Leachate is often discharged to wastewater treatment plants where the metal ions may have a toxic effect on the bacteria that are crucial in biological treatment. The metals settle and end up in the digested sludge, which often is returned to the waste deposit. This results in a harmful ecocycle.
Based on reports from the Swedish National Environmental Protection Agency, Isacson, Nilvebrant, and Öman realized that little research had been carried out in this area and that no simple and cheap method was available for the removal of metal ions. Together, they attempted to make ion-exchangers from natural and renewable materials like wood, bark, and lignin, which can capture metal ions and which are readily available by-products from Sweden's forest and pulp and paper industry. They proposed that the wood-based materials be isolated, dried, and used as solid fuel. They investigated how these materials could be activated with ozone and washing with alkali, and they measured the concentrations of metal ions using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP).
The results showed that the natural materials effectively captured metal ions in solution, thus demonstrating that bark, lignin, and wood can be used as natural ion-exchangers. Additionally, since the materials could be dried and burned after their use as ion-exchangers, their value as solid fuels would not be lost. The young men also proposed further studies to establish whether their method could be used in practice, particularly in comparison to currently available methods of leachate treatment.
U.S.—Characterization of potential fish pathogens where Pfiesteria piscicida outbreaks were reported
by Brenda Goguen
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| Brenda Goguen receives honors |
Using a sound scientific method and an elaborate testing protocol, Goguen's paper challenges the conventional wisdom that fish kills occurring in the Chesapeake Bay region are attributable to Pfiesteria piscicida. Goguen studied DNA in soil sediments taken from five rivers that empty into the Chesapeake Bay, from an experimental fish tank at the Center for Marine Biotechnology (COMB) in Baltimore, and from samples purported to be pure amoeboid Pfiesteria cultures (tester samples). Her results found that:
- Pfiesteria piscicida was present in small amounts only in three of the five rivers
- COMB samples showed no direct correlation between the organism and the fish kills
- Many of the tester samples were not pure because other organisms were present in them.
Taken together, the results of Goguen's studies cast doubt on the validity of the prevailing hypothesis that Pfiesteria piscicida preys on fish. Her research points out that there may be other organisms causing the fish kills and invites broader thinking and further study.
In addition, her study illustrates the importance of completely evaluating the circumstances surrounding epizoötic (a disease affecting a large number of animals at the same time within a particular region or geographic area) events, such as the fish kills in the Chesapeake Bay. Researchers, she writes, must ensure that they have studied all possible factors before making conclusions. This is particularly important as the livelihoods of many people depend on the water, and the true cause of an event such as a fish kill must be identified so that similar situations can be prevented in the future.
