Premium
Metabolism of streamwater dissolved organic carbon in the shallow hyporheic zone
Author(s) -
Findlay Stuart,
Strayer David,
Goumbala Cheikh,
Gould Kim
Publication year - 1993
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.1993.38.7.1493
Subject(s) - hyporheic zone , dissolved organic carbon , sediment , environmental chemistry , hydrology (agriculture) , surface water , chemistry , environmental science , geology , environmental engineering , geomorphology , geotechnical engineering
Approximately 50% of streamwater dissolved organic C (DOC) disappeared from interstitial water moving along a hyporheic flowpath below a gravel bar. Concurrent decreases in oxygen and increases in dissolved inorganic C (DIC) indicate metabolism of streamwater‐derived DOC by hyporheic microbes. Loss of 100 µ M DOC would account for 24–39% of the oxygen depletion and DIC accumulation. Sediments were incubated with DOC collected from the stream channel and two wells along the flowpath to examine whether streamwater and hyporheic DOC could support growth of sedimentary bacteria. Streamwater and hyporheic DOC collected from the upstream end of the flowpath stimulated higher bacterial growth rates and supported higher biomass than hyporheic DOC collected from the downstream end. The supply of streamwater‐derived DOC is a significant source of C for hyporheic sediment microorganisms, and these organisms are capable of using about half the DOC contained in streamwater.