Field Notes

<--2022-05-27 11:15:00 | 2022-06-28 10:50:00-->
Other sites visited today: Mayberry | Bouldin Corn | Hill Slough

Bouldin Alfalfa: 2022-06-08 14:30:00 (DOY 159)
Author: Daphne Szutu
Others: Carlos

Summary: Regular data collection/cleaning, took 1 soil core at each tower, alfalfa has been mowed, trimmed alfalfa, changed main tower eddy clock +2.5min

2022-06-08
Bouldin Alfalfa

Carlos and I arrived at 14:30 PDT. It was warm, mostly overcast, and windy. There was a sprinkling of rain a few days ago in the early mornings of 2022-06-05. The alfalfa field has been mowed but not raked. There was a sizeable patch of alfalfa around the bouncer tower; a little less alfalfa around the edge tower.

Main Tower

There was no Landsat8 overpass today so Carlos got started with spectral and veg height measurements and with trimming the alfalfa under the tower.

I downloaded met, cam, and USB GHG data. I downloaded the FD data and cleared its memory. I downloaded the IRT data by swapping the microSD card and using CardConvert to convert the fast data to TOB1 and the slow data to TOA5.

I changed the eddy clock +2:30min from 12:54:00 to 12:56:30. This is a larger offset than I expected. Keep an eye on this. I restarted logging afterwards.

I downloaded the photos and 10sec T/RH data and converted the T/RH data to a TOB1 file. I checked that the 10s data looked fine before clearing the card and re-inserting the card (forgot to swap the card here).

I removed the Adex CR1K and used CardConvert to convert the data to TOB1. I put in a fresh card and will save the raw files on the old card until the next site visit. I connected to the datalogger to download and check the 30min data—looked fine. I also checked through LoggerNet that the new card mounted correctly.

We took 1 soil core sample using the slide hammer. The core depth was 0-5cm. The soil felt dry but it was easy enough to pound the core in. For each sample, I leveled the edges of the core with the pocketknife (forgot a putty knife today), capped it with the blue plastic caps, taped the caps on electrical tape, and kept the cores in a plastic bag. I weighed the “wet” weights in the lab when we got back to campus.

I checked the datalogger and mux screws. Some were about ½-turn loose, but most of the mux screws that I had checked in the last few months were tight.

The 7500 read: 408ppm CO2, 716mmol/m3 H2O, 29.5C, 101.0kPa, 98SS – 99.5 after cleaning

Bouncer Tower

We got to the Bouncer Tower at 15:30 PDT. Carlos got started trimming the alfalfa. He took 1 soil core sample using the slide hammer. The core depth was 0-5cm. The soil felt dry but it was easy enough to pound the core in.

I downloaded CR6 (30min, 10s, 20Hz), CR23X (30min), and USB GHG (20Hz) data. For the CR6 10s and 20Hz data, I swapped the microSD card and used CardConvert to convert to TOB1. The raw data are still on the removed microSD card for now (remove before next site visit). I used the CSI/O cable to connect to the CR6 since Joe reported the microUSB port was busted. I checked the 30min data from the CR6 and CR23X and they seemed reasonable.

Carlos cleaned the 7500. The plastic 50ml bottle exploded while he was holding it, maybe from the heat?

I changed the eddy clock +35sec from 14:57:00 to 14:57:35. I restarted logging afterwards.

The 7500 read: 408ppm CO2, 620mmol/m3 H2O, 30.7C, 101kPa, 96SS – 100 after cleaning

Edge Tower

We got to the Edge Tower at 16:40 PDT. Carlos trimmed the alfalfa and took 1 soil core sample using the slide hammer. The core depth was 0-5cm. The soil felt dry but it was easy enough to pound the core in.

I downloaded CR6 (30min, 10s, 20Hz), CR23X (30min), and USB GHG (20Hz) data. For the CR6 10s and 20Hz data, I swapped the microSD card and used CardConvert to convert to TOB1. The raw data are still on the removed microSD card for now (remove before next site visit). I checked the 30min data from the CR6 and CR23X and they seemed reasonable.

The 7500 SS was 100 so we did not clean the sensor.

I changed the eddy clock +20sec from 15:56:10 to 15:56:30. I restarted logging afterwards.

The 7500 read: 413ppm CO2, 584mmol/m3 H2O, 30.3C, 10.9kPa, 100SS

We left at 17:15 PDT.

Next Mowing: 2022-07-05

Veg Height (cm): Tape measure from ground to top of plant - Mowed 5 days ago
10, 12, 15, 9, 8, 17, 6, 9, 10, 12, 13, 15, 10, 8, 9, avg = 10.9, stdev = 3.07

0 photos found

7 sets found

4 BA_flux graphs found