Field Notes

Bouldin Alfalfa: 2022-11-18 14:25:00 (DOY 322)
Author: Daphne Szutu
Others: Ari

Summary: Regular data collection/cleaning, many alfalfa fields on the island have been plowed, installed production Mark 3, removed one Mark II, swapped 7500 for calibration, downloaded intercomparison data, windy

2022-11-18
Bouldin Alfalfa

Ari and I arrived at 14:25 PST. It was windy, sunny, and cool. Most of the alfalfa fields we can see between Hwy 12 and our row of fields have been plowed. Only our row of alfalfa fields (and probably the row to the south) remain. I’ll reach out to someone to see if we need to move our equipment and when.

The alfalfa bales and un-baled piles we saw on our last visit have been removed. On our field, the alfalfa had been mowed before the last visit but I don’t think they bothered to rake or bale it. Looking at the phenocam photos back in the lab, I didn’t see any evidence of tractor work since harvest in late October. The alfalfa is still short and sparse, maybe 10cm tall.

I downloaded met, cam, USB GHG, FD, and IRT data. Ari cleaned flux and rad sensors and took spectral measurements.

Ari installed production Mark 3 sn B301045. We turned on the sensor by pressing the power button for 2sec and saw the various status lights blink. The new Mark 3 is on the north (short) side of the tower with the solar panel facing south and the sensors facing north, directly above the met box. Since we don’t need three Arables on the tower, she removed the Mark II sn C013433, its mount, and its solar panel. We chose to remove this one because the other Mark II is connected to the cup anemometer and soil profile.

We swapped LI-7500s for calibration: sn 1594 came off and sn 0073 went on. I uploaded a new config file, updated the pressure coefficients, and rest the box. I changed the eddy clock +45sec from 14:41:30 to 14:42:15 to match the laptop time and restarted logging.

I downloaded the intercomparison data from the Adex CR1000 and the two CR6s. Assuming this data looks good, we can remove the intercomparison sensors and dataloggers at our next visit. I also changed the Adex CR1000 program so that it saves up ~30days of 30min data on the datalogger memory.

1594 dirty read: 420ppm CO2, 219mmol/m3 H2O, 20.8C, 101.7kPa, 99SS
1594 clean read: 425ppm CO2, 210mmol/m3 H2O, 20.9C, 101.6kPa, 100SS
0073 fresh read: 426ppm CO2, 212mmol/m3 H2O, 19.9C, 101.6kPa, 102SS

We left at 15:35 PST.

Next Mowing: 2022-12-18

0 photos found

7 sets found

4 BA_flux graphs found