Field Notes

Twitchell Alfalfa: 2013-06-05 11:30:00 (DOY 156)
Author: Cove Sturtevant
Others: Sara, Laurie, Yanel, Jenny

Summary: Field full and flowery. Standard fieldwork. 7500 and sonic need birdie spikes, sonic covered in doodie. Put batteries in insulated box. Replaced ad hoc 7500 mount with official version. Put on CNR1 radiometer next to NR01 for night-time testing. Recorded

Twitchell Alfalfa
2013-06-05

We arrived at approximately 11:30 PDT. It was breezy and sunny about 19 C. The field looks about the same as last time, ~30 cm tall plants with purple flowery tops, but I think they mowed it between our trips. Jenny met us at the site, and her, Sara, Laurie, and Yanel did LAI, spectral, cleaned the solar panels, and helped get rid of the birdie doo ALL OVER the sonic transducers (see picture). We forgot to write in the notes last time that the 7500 and sonic need spines. Direly needed for next time. Spraying the sonic with the sprayer we brought for the solar panels got most of the mess off, and I went in gently with an alcohol-soaked cloth on the transducer head faces for the rest.

We brought an insulated box that Joe made for the batteries, and I put them inside. The batteries looked good and gave a sigh of relief to be out of the sun. I hooked up a permanent Ethernet cable to be able to connect to the 7550, and replaced MacGyvers ad hoc 7500 mount with an officially sanctioned version. We wanted to test the CNR1 (sn 020476) during night time so I stuck it in line with the NR01 that is currently at the site and uploaded a new program (downloaded the data first).

7500 readings:
CO2 = 375 ppm (395 after cleaning)
H2O = 750 mmol m-3 (650 after cleaning)
SS = 87.3% (92.8 after cleaning)
t = 22.6 C
p = 101.67 kPa
sos = 346.2 m s-1

Sara got serial numbers for the instruments:
Gill sonic: 120908
LI-7500: 2108
LI-7550: 0674
CR1000: 40322
CR10X: 16047
AM16/32: 11662
Solar charger: could not find
LED sensor: #4
AM25T: 6767

2 photos found

20130605TA_BirdDooOnSonic.jpg ( 2013-06-05 12:17:29 ) Full size: 968x1296
Bird droppings on the sonic