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  • Stroud Water Research Center: Our Findings
    of the Rockefeller grant studies at Stroud Water Research Center have pioneered the investigation of energy flow in streams As many as a billion bacteria plus millions of protozoa and hundreds of thousands of diatoms occupy a square centimeter of a streambed and the collective efforts of such microorganisms provide or process most of the energy that supports the visible life of the stream By teasing apart and reassembling a stream s web of microscopic components the Center s scientists have sought to describe its unseen life Tom Bott Lou Kaplan and chemist Rick Larson explored the linkages among watershed processes dissolved organic matter and bacterial production In the course of that work they applied to freshwater systems a concept known as the microbial loop which had been developed in marine studies It suggested that bacteria play a vital role in the food web by using organic matter excreted by algae and becoming a direct food resource for more complex organisms These investigations have advanced in two directions What happens to the bacteria and how important is the transfer of energy through microscopic animals to higher organisms such as insects and fish And what is the chemical structure of dissolved organic matter and how does it influence the availability of food to groups of decomposers Later Laurel Standley contributed to both efforts following the transfer of toxins through the food web and using organic molecules to trace the movement of dissolved organic matter from the watershed to the stream Both strands build on the insights gained from the Rockefeller studies and the River Continuum Concept Their goal is to understand the critical relationship between land and water in stream ecology and to describe the interconnectedness of microorganisms with the visible members of aquatic communities in our streams and rivers Explore

    Original URL path: http://www.swrc.org/research/findings/microbes.shtm (2016-04-27)
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  • Stroud Water Research Center: Our Findings
    Water s Edge Lecture Series Contact Us News What s New News Releases Media Coverage SAFE Water Award Newsletters Annual Reports Search Groundbreaking Research Sediment Toxicity Flora and fauna that live in streams are often exposed to toxic contaminants which have accumulated in sediments The toxic effect of these contaminants to animal life cannot be predicted simply from the total amount of contaminant present Factors such as sediment chemistry and the manner in which the flora and fauna feed determine in part to what extent aquatic organisms take up the contaminants Drs Laurel Standley and Thomas Bott investigated chemical and biological factors that influence the accumulation of toxic contaminants in biota living on or within sediments Many decisions about environmental exposure to contaminants such as whether to allow the dredging of river channels or the consumption of fish and shellfish are now based on procedures that use strong chemical solvents Standley and Bott s work documents that such an approach is overly simplistic and does not adequately mimic nature Explore Our Research Projects Findings Overview Rockefeller Study River Continuum Microbes Molecules Sediment Toxicity Streamside Reforestation Thermal Equilibrium Watershed Tea Stroud Patents Research Groups People Weather Station Research Home Search our

    Original URL path: http://www.swrc.org/research/findings/sediment.shtm (2016-04-27)
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  • Stroud Water Research Center: Our Findings
    s New News Releases Media Coverage SAFE Water Award Newsletters Annual Reports Search Groundbreaking Research Streamside Reforestation An Analysis of Ecological Benefits and Societal Perceptions It is now generally accepted that streamside forests represent the best management practice for protecting aquatic ecosystems from outside pollution by filtering out nutrients sediments and toxic contaminants before they get to the stream In Streamside Reforestation which involves 18 streams Center scientists are evaluating their hypothesis that deforested streams deteriorate because of their need to process the dissolved nutrients particulate organic matter and organic pesticides that enter from the watershed The scientists have designed specific field experiments to test their beliefs that forested streams are consistently wider and so have more bottom surface area per unit length than contiguous meadow reaches and narrow stream width and the accompanying unnatural light temperature and water velocity levels associated with deforestation cause significant changes in the structure and productivity of algal macroinvertebrate and fish communities In addition the project seeks to identify and quantify social and economic issues that affect the restoration of streamside forests Explore Our Research Projects Findings Overview Rockefeller Study River Continuum Microbes Molecules Sediment Toxicity Streamside Reforestation Thermal Equilibrium Watershed Tea Stroud Patents

    Original URL path: http://www.swrc.org/research/findings/riparianbuffer.shtm (2016-04-27)
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  • Stroud Water Research Center: Our Findings
    in streams and rivers Initial laboratory experiments focused on the tolerances of individual species but field research indicated that the correlation between survivorship and water temperature was more complicated than the limits established in the laboratory In 1972 Bern Sweeney and Robin Vannote abandoned the idea of thermal limits and hypothesized that temperature changes altered the normal developmental and growth characteristics of a species which in turn reduced its adult size and reproductive activity Their Thermal Equilibrium Concept proposed two hypotheses That for many cold blooded aquatic animals especially insects a direct correlation exists between water temperature and reproductive potential and That changing temperature cycles affect the geographic distribution of a species by gradually lowering its reproductive vitality Between 1980 and 1985 these ideas were put to a rigorous test on 25 river systems that stretched across the eastern Piedmont region of North America from Florida to Quebec This remains the largest project ever undertaken at Stroud Water Research Center and its results confirmed the essential tenets of both hypotheses While many species evolve elaborate genetic mechanisms to cope with severe seasonal changes in temperature such adaptations offer little protection against human activities In a world increasingly intent on protecting

    Original URL path: http://www.swrc.org/research/findings/thermal.shtm (2016-04-27)
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  • “Watershed tea,” drinking water and climate change
    in stream Photo Christina Medved Watershed tea drinking water and climate change Stroud Water Research Center scientists discovered that when rain water enters a stream it carries with it a special blend of dissolved organic matter which is then dispersed in the water much like tea from a tea bag Every watershed produces a unique tea that nourishes a unique bacterial community So specific is each watershed s tea that migrating salmon use it to find their way home at spawning time The tea provides food for bacteria and studies at Stroud Center indicate that each watershed produces a community of bacterial species which are uniquely fitted to the local supply of watershed tea Understanding stream processes can lead to better drinking water treatments With water utilities turning increasingly to biological filtration to remove impurities from drinking water the more we know about how bacteria consume organic matter the better we can design and evaluate these purification systems If they prove effective water utilities will be able to reduce their dependence on chemical disinfectants which will be more cost effective for them and less harmful to consumers and the environment Organic matter delivered to oceans impacts climate change Much of the organic matter ultimately ends up in the ocean where over time it can be degraded to carbon dioxide a greenhouse gas By studying the interactions of bacteria and watershed tea Stroud Center scientists hope not only to help provide clean drinking water in a world where it is in dangerously short supply but also to understand how the organic matter that is delivered to oceans impacts global climate change Learn more Visit the Leaf Pack Network website to learn about the diverse microbial and macroinvertebrate communities that depend on natural leaf packs and watershed tea Explore Our Research Projects

    Original URL path: http://www.swrc.org/research/findings/watershed.shtm (2016-04-27)
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  • Fluvial Geomorphology Group at Stroud Water Research Center
    physical riverscape that form the basis of river ecosystems Our lab studies the movement of water sediment organic matter nutrients and other molecules through watersheds to better understand watershed hydrology geomorphology and biogeochemistry We also investigate how watershed land use and river channel restoration practices influence hydrologically mediated processes such as surface groundwater interaction sediment transport and channel evolution Melinda D Daniels Ph D Associate Research Scientist Fluvial Geomorphology Lab Director Fluvial geomorphology hydrology and stream ecosystem ecology of both natural and human modified river systems from reach to watershed scales Profile Email J Denis Newbold Ph D Research Scientist Emeritus Ecosystem Processes Flow of nutrients to streams and rivers and how those nutrients are processed transformed and transported by the stream and river ecosystem Profile Email Lindsey K Albertson Ph D Postdoctoral Researcher Biophysical interactions in river ecosystems heavily influenced by deforestation and urbanization linking species abundances and interaction with stream geomorphology Profile Email Valérie Ouellet Ph D Postdoctoral Researcher Understanding how different environmental variables such as water temperature flow etc affect the habitat of key fish species Profile Email Frank Klein Ph D Volunteer Preparing processing and tracking stream fall in samples organic matter that falls into streams

    Original URL path: http://www.swrc.org/research/groups/fluvial-geomorphology.shtm (2016-04-27)
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  • Climate Reference Network Station » White Clay Creek at Avondale, Pa.
    Home Donate Now Planned Giving Event Calendar Volunteer The Water s Edge Lecture Series Contact Us News What s New News Releases Media Coverage SAFE Water Award Newsletters Annual Reports Search Research US Climate Reference Network Station at Stroud Water Research Center Back to CRN station overview Explore Our Research Projects Findings Research Groups People NOAA Weather Station Research Home Search our site Research Critical Zone Observatory Schuylkill River Project

    Original URL path: http://www.swrc.org/research/noaa_crn_map.shtm (2016-04-27)
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  • Education » Student Programs
    Water Award Newsletters Annual Reports Search Education Free Stream Ecology Programs The Education Improvement Tax Credit EITC program allows Stroud Center to offer programs at no cost for grades 4 and up in Pennsylvania public schools Find out more Student Programs The education staff at the Stroud Water Research Center has been at the forefront of developing unique programs for students providing a variety of field experiences in the setting of a dynamic research facility The following programs are available for students in grade 4 and up For more information please contact our educators She taught in a way that we could remember it She made it fun Student Kennett School District PA On site visits to Stroud Water Research Center Four hour program is 350 per class of 24 students Maximum of two classes per day Stream School Using the Center s 1 800 acre experimental watershed as a living laboratory students explore the physical chemical and biological characteristics of streams Specific activities include a macroinvertebrate survey habitat assessment and chemical analysis of a stream system What was covered will reinforce what we do in the lab and classroom Teacher Haddonfield High School NJ Off site programs at your school or field site Typical programs begin at 160 hr Cost may vary depending on travel Outreach programs into schools provide classroom and schoolyard activities as well as events serving the entire school population Programs can be tailored to meet your needs Stream Critters Go To School What lives in local streams How do these animals eat and breathe Students in grades 4 7 have fun investigating a real stream sample to learn about aquatic insects and stream health One hour program Learn More Leaf Pack Network Programs Contact Us Projects Treks Sojourns For Educators Student Programs Educator Workshops Curriculum

    Original URL path: http://www.swrc.org/education/educators/students.shtm (2016-04-27)
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