Field Notes

<--2016-10-26 13:20:00 | 2016-11-16 11:30:00-->
Other sites visited today: East End | Twitchell Rice | West Pond | Sherman Wetland

Twitchell Alfalfa: 2016-11-08 11:00:00 (DOY 313)
Author: Elke Eichelmann
Others: Kyle Hemmes, Dennis Baldocchi, Tyler Anthony, Heather Dang

Summary: Regular data collection, soil sampling in tower footprint

Arrived at 11:00. It was sunny, warm and clear with a light breeze.

We met with Tyler and Heather from Whendee Silverâ€™s lab to collect soil samples for bulk density, and soil chemistry (C, N, Fe). Soil samples for chemistry analysis were collected along three parallel transects, each 5m apart, with 5 sampling points, also each 5m apart. Samples were collected within the footprint of the eddy flux tower, starting approximately 10m west of the tower base and moving westwards from there.
At each sampling points three soil samples were collected one each from 0-15cm, 15-30cm, and 30-60cm.
There was one pit dug to the North-West of the tower for bulk density samples. One set of bulk density samples was collected in 5cm (not sure about this number) increments from the top down to 60cm depth.

We collected USB GHG data, collected met data, collected soilCO2 data, collected radiation data. All looks good.

Swapped CF camera card. Collected 5 biomass samples and veg height.
Veg height in cm: 26, 37, 25, 26, 21, 27, 36, 33, 25, 47, 36, 29, 34, 44, 46, 40, 42, 35, 42, 37

Did soil respiration measurements. The LI6400 seemed to work fine again after the O-rings had been replaced in the lab.
Took spectral readings.

LI7500 readings:
CO2 410.1 umol/mol
H2O 736 mmol/m3
T 21.45 Celsius
P 101.91 kPa
SS 83.5 -> 86.2 after cleaning

Left at 13:05

Veg Height (cm): Tape measure from ground to top of plant - not quite flowering, could be ready soon for final cut
26, 37, 25, 26, 21, 27, 36, 33, 25, 47, 36, 29, 34, 44, 46, 40, 42, 35, 42, 37, avg = 34.4, stdev = 7.73

0 photos found

7 sets found

Can't check TA_met
11 TA_met graphs found