Field Notes

Twitchell Alfalfa: 2013-06-27 12:00:00 (DOY 178)
Author: Cove Sturtevant
Others: Laurie, Yanel

Summary: Alfalfa has been mowed. Took soil cores. Bumped flux system to 20 Hz. Pulled CNR1 (was being tested alongside NR01).

Twitchell Alfalfa
2013-06-27

We arrived at 12:00 PDT. It was sunny and hot (29 C), but with a nice breeze. The alfalfa has been mowed down to nubs and raked into rows. There remained a patch up unmowed alfalfa around the radiation boom that I clipped down. The pole with the sonic and 7500 was tilted just slightly off vertical toward the east I righted it.

I downloaded data and attended to the tower while Laurie and Yanel took soil cores. I think 10 cores were taken along a N-S transect. I will let Laurie fill in further details.

I switched the sonic and GHG system to 20 Hz as a result of some high frequency spectra dropoff noted in the data. I also bumped the sonic serial communication to a baud rate of 58600. I also pulled the CNR1 being tested alongside the NR01 on the radiation boom and switched the program back to normal.

7500 readings:
CO2 = 401 ppm (407 after cleaning)
H2O = 700 mmol m-3 (660 after cleaning)
SS = 91.4% (93.5% after cleaning)
T = 32.8 C
p = 101.7 kPa
sos = 352.8 m s-1

MET looked good. Cleaned the radiation instruments. Checked the 7550 clock settings: A-OK.

1 photos found

TA_autocam_20130627_1215.jpg ( 2013-06-27 12:15:02 ) Full size: 1920x1440
finished mowing the field