Taking Measurements in the Field
Taking Measurements in the Field:
Connect the nitrate, ammonium, calcium, and dissolved oxygen probes to the channels in the LabPro. Turn on the calculator and follow the commands to the "setup" screen. Select "save/load experiment" and then select "load experiment" from the following screen. Choose the appropriate experiment from the menu of choices. The calculator should indicate that it is "loading" the experiment.
Next, follow the commands back to "setup" screen.
Submerge the probes in the creek so that they are not touching the bottom, leaves or debris, the shore, or any rocks. Make sure that the probe is submerged enough to cover the white dots on the probe, just above the black rubber tip. With these four probes submerged and not touching each other, select "start" from the menu. The calculator should indicate that it is "Collecting data for 10 seconds," after which it should give an averaged value of the readings for each of the probes. Record these numbers on the data collection sheet. Press Enter.
Disconnect the probes from the LabPro.
Connect the conductivity and the flow rate probe into the channels on the LabPro.
From the "setup" screen, select "save/load experiment" and then select "load experiment." From the list given, choose the appropriate experiment. Press Enter. Return to the "setup" menu and select "start." The calculator will indicate that it is collecting data for ten seconds, and then give an averaged number for the two probes. Record these on the data sheet, and press "ENTER." Quit the program and turn off the calculator (to save battery power).
Submerge the end of the pH probe into the creek for at least two minutes or until the value stabilizes. Record this number as the pH value on the data sheet. Also submerge the thermometer in the creek for at least two minutes and record the temperature of the water on the data sheet.
Go to the remaining sample locations and repeat the procedure for taking
measurements in the field as described above.
Developed by Emily Blackwell with assistance from Dr. Mark Lassiter
This procedure is a modified version of the procedures for
:
| Vernier LabPro Probes | Extech Economy Oyster pH Meter Kit |
| Vernier Software & Technology | Extech Instruments Corporation |
| 13979 S.W. Millikan Way | 335 Bear Hill Road |
| Beaverton, OR 97005-2886 | Waltham, MA 02154 |
| www.vernier.com | Fax: (617) 890-7864 |
Site prepared by Mark Lassiter, 1/23/2002