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ARS Home Office of Communications Images Photos Sept20





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d4219-1headline bar  A scientist placing sampling equipment into a stream**Image Number d4219-1** Peter Downey, an agronomist with HRSL, prepares to deploy a series of POCIS (polar organic chemical integrative samplers) in a tributary of the Chesapeake Bay. These samplers capture organic compounds in the water which can be used as tracers for nitrate from agricultural and urban sources. These samplers will remain submerged in the waterway for 28 days and then will be retrieved and analyzed.  Photo by David Bartels. 640 pixels wide: (d4219-1.jpg)   Please visit our Image Gallery.


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