Field Notes

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Other sites visited today: West Pond | East End | Bouldin Corn | Mayberry

Gilbert Tract: 2022-06-09 08:15:00 (DOY 160)
Author: Daphne Szutu
Others: Ari

Summary: Regular data collection/cleaning, calibrate 7700, dfPAR motor dead--fixed, downloaded SL beam check data, eosGP CO2 data not working, changed eddy clock +3min

2022-06-09
Gilbert Tract

Ari and I arrived at 8:15 PDT to the Side-Looker. It was still mild with a cool breeze and thin high clouds covering most of the sky, but it will be a hot day later. It was near low tide. There was a clear gap in the water weeds where we laid the concrete panels down, but still plenty of weeds growing to the side of the railing and some beyond the far edge of the concrete panels.

Ari downloaded the SL data and beam check data to send to SonTek. In the interface there is a place to manually start recording beam check data. It looks like there’s a 1 measurements/second. After each measurement, the interface recalculates the average of all measurements until you stop recording. Only the final average file is saved. I think the final file is an image only, no data table. We restarted logging.

We got to the main tower around 9:00 PDT. The wetland is nice and green. Molly and others from River Partners drove by; they were working on some replanting. I downloaded met, cam, and USB GHG data. I changed the eddy clock +3min from 8:25:00 to 8:27:55 and restarted logging. I downloaded the miniDOT data and swapped its desiccant.

We calibrated the LI-7700 sn TG1-0424, which looked fine. The optics RH was 16% so I left the desiccant as is.

Ari cleaned flux and rad sensors. We topped off the wash reservoir.

The eosGP CO2 reading was not working, but temperature was ok. All the wiring looked fine, so maybe I need to bring a replacement sensor (if we have one).

The dfPAR motor was dead. I replaced it with a new motor from the blue bag. It was difficult to get the shadowband off of the shaft of the new motor until I sprayed it with the WD-40 alternative and spun and tugged at the band to get it off. I dropped one of the screws that holds the motor against the enclosure—need a replacement next time.

The staff gauge read 37cm at 9:12 PST, right before we left.

The 7500 read: 414ppm CO2, 620mmol/m3 H2O, 19.7C, 101.1kPa, 97SS – 98 after cleaning
The 7700 read: 2.1ppm CH4, 35RSSI – 80 after cleaning

We left at 10:12 PDT.

Looking at the data back in the lab, Joe noticed that NDVI 650in started decreasing in mid-May and dropped by about 1/3 over a week. This sensor is probably going bad.

1 photos found

gilberttract_2022_06_09_081405.jpg ( 2022-06-09 09:15:22 ) Full size: 1296x960
7700 calibration in progress