CF012
Stream specific conductance and temperature from small watersheds in the Andrews Forest

CREATOR(S): Sherri L. Johnson

PRINCIPAL INVESTIGATOR(S): Sherri L. Johnson

ORIGINATOR(S): Sherri L. Johnson

OTHER RESEARCHER(S): Catalina Segura, Adam M Kennedy, Stephanie A Schmidt

DATA SET CONTACT PERSON: Stephanie A Schmidt

METHOD CONTACT: Greg Downing

FORMER INVESTIGATOR: Don Henshaw

METADATA CREATION DATE:

22 Sep 2015

MOST RECENT METADATA REVIEW DATE:

22 Sep 2015

KEYWORDS:

hydrology, water chemistry, electrical conductivity, specific conductivity, water temperature, watersheds, aquatic ecosystems, long term studies

METHODS:

Experimental Design - CF012:

Description: Specific conductance is measured in conjunction with the small watershed studies which also collect proportional streamflow samples, measure streamflow, and measure air and water temperature at the gauging stations.

Field Methods - CF012:

Description: Specific conductance is measured with a Campbell Scientific CS547A electrical conductivity and temperature probe connected to a Campbell Scientific data logger. The sensor is installed in a small pool just upstream, downstream or directly across from the flume / gage house depending on the site. Instantaneous measurements of specific conductance and water temperature are made every 5 minutes. During periodic (approximately every 6 to 9 weeks) field visits, independent check measurements are made using a portable YSI Pro30 as of August 2015 and previously a YSI 30 conductivity meter. Should the CS547A measurement differ from the YSI measurement, the temperature coefficient used in calculating conductance is modified in the data logger program in the field to better match the CS547A output with the YSI check measurement. In the early years of operation the cell constant was modified to better match these values, but that is no longer done. Additionally, the probes are regularly brushed during field visits to improve operation.

Instrumentation: A Campbell Scientific CS547A electrical conductivity and temperature probe connected to a Campbell Scientific data logger is used in conjunction with a portable YSI Pro30 conductivity meter.

SUPPLEMENTAL INFORMATION:

NSF grants: DEB-0823380, DEB-1440409

SITE DESCRIPTION:

Continuous streamflow data have been collected over varying periods of record in eight first to second-order watersheds, one third-order watershed, and the fifth-order watershed in the H. J. Andrews. Watersheds 1, 2, and 3 comprise a low-elevation (442 m to 1082 m) set of experimental basins with Watershed 2 serving as the control. Watersheds 6, 7, and 8 comprise a high-elevation (863 m to 1190 m) set of experimental basins with Watershed 8 as the control. Watersheds 9 and 10 are a low-elevation pair of small watersheds with Watershed 9 as the control. Mack Creek is a control basin and has not been harvested. The gauged portion of 5th-order Lookout Creek comprises nearly all of the Andrews Forest.

TAXONOMIC SYSTEM:

None

GEOGRAPHIC EXTENT:

H.J. Andrews Experimental Forest

ELEVATION_MINIMUM (meters):

439

ELEVATION_MAXIMUM (meters):

962

MEASUREMENT FREQUENCY:

5 minutes

PROGRESS DESCRIPTION:

Active

UPDATE FREQUENCY DESCRIPTION:

annually

CURRENTNESS REFERENCE:

Observed