Helping To Build the Next Generation of Scientists

May 6th, 2012 @

Vincent Lin and Jim Tang

The Ecosystems Center staff plays an active role in community outreach and education. Every year, scientists and research assistants volunteer to mentor students from the middle school and high school levels, helping them to refine ideas for their science fair projects. Many of the staff are also involved in judging projects at both the local and state science fairs.

Mentoring of seventh and eighth grade students at Lawrence School is organized by the Woods Hole Science and Technology Educational Partnership (WHSTEP). In 2012, Ecosystems Center researchers JC Weber, Sam Kelsey, Lindsay Scott, Suzanne Thomas and Kate Morkeski spent several hours with the students, helping them develop their science project ideas and organize their approach and methods. Other Ecosystems staff, eager to help the next generation of scientists, also mentored several motivated high school students who approached them independently with their scientific interests.

This year, three Falmouth High School students who were advised by Ecosystems Center scientists went on to win top awards at the Falmouth Public Schools Science Fair on March 3. The following week, all three won prizes in the South Shore Regional Science Fair at Bridgewater State University and will next compete in the Massachusetts State Science and Engineering Fair at MIT in May.

Vincent Lin, a junior at Falmouth High School who was mentored by Ecosystems Center scientist Jim Tang, won first prize at the Falmouth fair. He also received the Mary Sears Scholarship from the Woods Hole Oceanographic Institution as well as an award from the National Marine Fisheries Service. His project was "Effects of Fertilization and Temperature on Greenhouse Gas and Nitrogen Oxide Emissions from Soils." Jim commented on the project, "The results will inform us how to appropriately fertilize lawns and agricultural crops in order to decrease greenhouse gas emissions and increase carbon stocks in soils." Vincent will represent Massachusetts at the International Science and Engineering Fair in Pittsburgh this May. This was Vincent's third year winning of first prize at the science fair.

Another FHS junior, Ted Price, received first prize for his project, "Light Attenuation in West Falmouth Harbor." Melanie Hayn, research assistant at the Ecosystems Center, was his advisor. In addition, Ted was awarded a prize from Hydroid, Inc. His project looked at the factors that affect light penetration in West Falmouth Harbor. "He was interested in why you could see further below the water surface at some locations than others, and wanted to figure out what was responsible," noted Melanie. Ted looked at many factors, including chlorophyll, colored dissolved organic matter, suspended solids, salinity, and tidal state.

Steven Spall won second prize for his study of "Biomass Denitrification in Saltwater Estuaries." His mentor was Ken Foreman, director of the Ecosystems Center's Semester in Environmental Science. Steven won the Dr. Donald Zinn Award from the Salt Pond Area Bird Sanctuaries, Inc., and was selected as alternate to Vincent Lin for the International Science and Engineering Fair. The goals of his project, said Ken, were to use microcosms filled with wood chips to simulate a permeable reactive barrier designed to promote denitrification in the groundwater. Steven also evaluated the lifetime of the wood chips by measuring the decomposition of the wood via the release of carbon dioxide from the degradation of the wood in the outgoing water vs. the incoming water.

Ecosystems Center staff who judged at the Falmouth Public Schools science fair were JC Weber, Marshall Otter, Jim Tang, Suzanne Thomas and Miriam Johnston. Falmouth Academy's science fair, held in February, was judged by Hap Garritt. Marshall, Hap and JC also judge the science fair at the state level at MIT.

Volunteering in these educational initiatives gives the center staff an opportunity to share their own passion for science with the next generation of young scientists. “It’s an incredibly rewarding experience seeing the excitement and enthusiasm about science within the kids and the pride that they exude when presenting their final presentations,” noted Ecosystems research assistant JC Weber.

Green To Measure Growth: Assessing Eutrophication's Effects on Mummichogs

May 5th, 2012 @

As part of his research on preserving healthy and productive salt marshes, James Nelson, postdoctoral researcher at the Plum Island Sound Long Term Ecological Research site, turned 28,500 mummichogs green last summer.

Dr. Nelson explains: "Salt marshes, such as the Great Marsh along the northern Massachusetts coast, are highly productive landscapes that provide a great number of ecosystem services. Some of the more well known ecosystem services provided by salt marshes are protection from storm surge and runoff filtration. There is another major service salt marshes provide that ecologist have long theorized about but rarely demonstrated and that is the export of food to adjacent habitats in the form of fish.

Each year in the spring the productivity engine of the marsh gets switched on and begins to produce enormous amounts of biomass in the form of small fish. These fish, primarily mummichog (Fundulus heterclitus), follow the pulse of the tides to feed on the abundant food in the relative safety of tidal creeks throughout the spring and summer. As the temperatures dip into the fall season these little fish must move out of the shallow tidal creeks and into deeper waters, where they become prey for larger fish such as striped bass (Marone saxatilis). Essentially, salt marshes act as food factories that package large amounts of production in a short period and then export that production to organisms in other systems. In fact, we have observed a strong correlation between the amount of mummichog produced and the number of striped bass. Therefore, maintaining healthy and productive salt marshes will help to maintain productive offshore fisheries.

"Human-caused nutrient pollution, however, is a major threat to the stability of this important ecosystem service. My work focuses on the effects of 'eutrophication' or human-caused nutrient pollution on the secondary (fish) productivity of salt marshes. To examine this I employ a number of techniques with the primary goal of answering two main questions: first, how does nutrient pollution change the number of fish the salt marsh can support? And second, what are the effects on fish growth from nutrient pollution? By knowing the number of fish and their rate of growth we can calculate the total production of fish in the salt marsh. Of course, actually determining fish growth in the wild can be quite difficult.

"This summer I utilized a new technique that marks the bones, and other hard parts, of fish with a fluorescent dye (Calcein) that can be used to determine a fish’s growth rate. The fish are marked by immersing them in a non-toxic solution of Calcein and salt water for two minutes. A major advantage of this method is the number of fish we can mark at one time. This summer I was able to mark 28,500 fish in a two-day period. The dye does not harm the fish and cannot be seen in normal light, so the fish’s natural behavior is not affected. Once marked with the Calcein the bony structures will glow green under ultraviolet light. The marked fish were released back into the creeks from which they were captured to grow during the summer. We conducted monthly sampling of the fish in these creeks to recapture the marked fish. In the lab an ultraviolet light will be used to illuminate the Calcein mark. We will then measure the additional growth beyond the calcein mark on several bony structures to determine the fish’s growth during its time at liberty. If we are successful we will be able to answer the question of how eutrophication affects the growth rate of these fish and draw conclusions about the overall effect eutrophication will have on the export of secondary production from marshes to fisheries species offshore."