Field Notes

<--2020-05-01 14:50:00 | 2020-05-29 11:00:00-->
Other sites visited today: East End | West Pond | Bouldin Alfalfa

Bouldin Corn: 2020-05-19 08:45:00 (DOY 140)
Author: Daphne Szutu
Others: Joe, Ariane

Summary: Moved tower/soil sensors into field, many corn volunteers, 7700 calibration, swapped 7500 for calibration, installed upward picams, dug new well and installed water level sensor again

2020-05-19
Bouldin Corn

Joe, Ariane, and I arrived at 8:45 PDT. It was mild with a cool breeze and mostly cloudy with large cumulus clouds. There were crop dusters buzzing to and fro the whole morning.

Tyler was not exaggerating when he said there were a lot of volunteer corn plants by the tower and in the field in last yearâ€™s leftover patch. Joe noticed some of the bunches look like whole corn cobs that have sprouted. The three of us cleared weeds in front of and around the tower, and then dragged the tower forward about 8m to the edge of the planted corn. We pulled the wire loose from the current sensor (didn't replace), but everything else seems ok. Ari headed off to WP to try out the new peat corer.

New sonic orientation: 4 deg magnetic

Joe reinstalled the 3 sets of soil sensors (soil moisture, thermocouple rods, and heat flux plates), avoiding the area with many volunteer plants. The three Campbell soil moisture probes went in at 0-10cm, 10-20cm and 20-30cm. We also installed three picams in the same area â€” two have a fisheye camera lens (sn RPI0W-001, sn RPI0W-002) and one has a regular camera lens (sn RPI0W-004). The remaining FD chamber sn FD20180067 was also reinstalled in the field - it needs a shorter collar and maybe some friends.

(Note 2020-09-25: Joe says, "The one to the north was 0-10, the middle on 10-20, and the south on 20-30." Our best guess is VWC1 = 0-12 cm, VWC2 = 20-32cm, VWC3 = 10-22cm.)

Soil sensors moved:
Theta probe sn M003370
VWC CS655 sn 17133, sn 17128, sn 17129
Water level sn 70011234
SHF sn 11326, sn 10867, sn 10861
eosFD sn FD20180067

Joe also dug a new well under the new tower location and installed the water level sensor.
Water level from top of well = 131 cm (4.3â€™)
Top of well to ground = 47 cm
Top of well to sensor = 138 cm
Sensor psi reading = 0.12 psi ~ 8 cm (checks out with physical measurement!)

We calibrated the 7700 sn TG1-015. The offsets were small. The 7700 TC protection tubing fell off, which should be replaced. We also swap the 7500 for calibration: sn 75H-2668 came off and sn 75H-2176 went on. I sent a new configuration file, updated the pressure coefficients, and reset the 7550 box. I confirmed the 7700 was connected and the USB was logging. The eddy clocks looked good.

I downloaded met, cam, FD, PurpleAir and USB GHG data. I did not clear the FD memory. The PurpleAir microSD-SD extender cable looked a bit weathered, and the most recent file is from 2020-05-17. We probably need another extender cable.

Joe cleaned the flux and rad sensors and the camera window. The wash reservoir was mostly full, and we topped it off.

LI-7500 readings (sn 75H-2668 --> sn 75H-2668 after cleaning --> sn 75H-2176):
CO2 416ppm --> 420 --> 424
H2O 509ppm --> 479 --> 486
T 17.0C --> 17.2 --> 17.9
P 100.9kPa --> 101.0 --> 101.9
SS 102--> 102 --> 102

LI7700 readings (before calibration -->after cleaning --> after calibration):
CH4 2.0ppm --> 1.97 --> 1.95
RSSI 37--> 88--> 84

We left around 11:05 PDT.

1 photos found

20200519BC_Volunteers.jpg ( 2020-05-19 11:02:25 ) Full size: 1920x1062
Soil sensors, picams, and FD chamber reinstalled on the corn field, away from the many corn volunteers.