Field Notes

Bouldin Alfalfa: 2020-10-05 12:50:00 (DOY 279)
Author: Joe Verfaillie
Others:

Summary: Delta Tunnels people out, added Arable cup anemometer and vane, swapped FD chamber and added relay, moved camera closer to window

Bouldin Alfalfa
2020-10-05

I arrive at about 12:50. . It was hot and hazy with little to no wind. The air quality was on the border of â€œUnhealthy for sensitive groupâ€ and â€œUnhealthyâ€ at about 150 AQI. There were vehicles blocking the levee road so I drove the lower road along the levee. People seemed to be surveying along the levee and pounding in markers. I saw a bunch of trucks marked DCA go past Corn while I was there too. Turns out itâ€™s The Delta Conveyance Design and Construction Authority â€“ the tunnels project.

The alfalfa is tall and healthy looking. Fields to the north have been mowed.

I installed a Davis Instruments cup anemometer and vane for Arable at 2m above ground level on the corner of the scaffolding with the sonic. A wire runs to a break out box (aux bridge) I installed near the Arable Marks on the other side of the scaffolding and plugs into the Mark II. The conduit clips on the box were too big for the scaffolding railing and too small for the frame. I should swap them out for a better size.

I collected the data.
The 7500 read: 400.4ppm CO2, 541.1mmol/m3 H2O, 31.0C, 101.5kPa, 102.5SS
After cleaning: 418.2ppm CO2, 431.6mmol/m3 H2O, 110.6SS â€“ we should rested this SS next calibration
The 7700 read: 2.05ppm CH4, 37.7RSSI â€“ 78.4 after cleaning
I topped off the wash reservoir.

I checked the screw terminal connections on the 24V to 12V converter â€“ these seemed fine. But we could swap out the converter for a more robust version.

The FD Chamber here sn FD20180048 is reading low CO2 concentrations â€“ this does not seem to affect the flux but is not technically good and can supposedly be corrected using the eosLink-FD software. I replace the chamber with sn FD20180047 which is the one that has high temperature start up problems. To fix this I added a normally closed optical relay to restart the chamber near midnight. After downloading the met data I uploaded a new program that uses C6 to open the relay during the first minute of the day. C6 was previously used by the sonic range finder â€“ this code was still active so I commented it out of the current program.

I pushed the Stardot camera closer to the window â€“ its view had the corners on the enclosure in the frame.

I tried to do spectral measurements but the fiber optic cable did not have the diffuser on the end. The diffuser is chipped and I was going to order a new one so it might be on my desk.

I measured veg ht.

I left at about 14:30

Next Mowing: 2020-10-07

Veg Height (cm): Tape measure from ground to top of plant
67, 54, 54, 70, 49, 58, 50, 50, avg = 56.5, stdev = 8

0 photos found

7 sets found

5 BA_flux graphs found