Field Notes

<--2018-08-07 14:41:00 | 2018-08-23 14:55:00-->

Sherman Wetland: 2018-08-08 10:00:00 (DOY 220)
Author: Elke Eichelmann
Others: Patty Oikawa

Summary: Leaf level measurements with LI6400, swapped camera card

We arrived around 10am, it was a mostly sunny and clear day with a light breeze, but it was a little hazy from the wildfire smoke.

We took measurements of fractionation of dark respiration and photosynthesis with the LI6400 and LGR for tule at Sherman wetland.

The Silver lab 6400 with the clear conifer chamber was set up on the ground just East of the tower.
Measurements were taken 1/3 or the length of the leaf down from the tip (total length measured from where the leaf splits off from the base of the plant). Measurements were taken on three different leafs. The chamber was sealed with additional putty after closing to ensure it was completely sealed.
We measured two of the transplanted tule which were still completely green. Most of the transplanted tule had died or had brown tips, but we found two smaller ones that were still completely green. We also measured one large tule that was cut in a different part of the wetland. The cut edge was kept under water in a jug and the plant was moved to the tower for measurement.

After the readings inside the chamber had reached stability at a certain light level and a measurement point was taken with the LI-6400, the chamber outlet was connected to the LGR gas analyzer to get isotopic composition of the CO2 gas exchange.
For each leaf, measurements were taken at two light levels: approximately 1500umol/m2/s ambient full sun (high light photosynthesis) and 0umol/m2/s with the chamber fully covered by 8 layers of window screen and one layer of blackout curtain (dark respiration). No other parameters were controlled (ambient incoming CO2, ambient temperature, ambient H2O).

For the last leaf, the leaf was cut off under water before the measurement and put in a separate water container with DI water. It was cut off again in there and the same measurement procedure was performed (high and low light) to see if there is a contribution of oxidized methane in the original CO2 signature.

We also swapped the camera card for the phenocam, since the field crew forgot to do that the day before when they were out for regular maintenance.

We left around 2pm.

0 photos found

7 sets found

Can't check MBWPEESWGT_mixed
Can't check MBEEWPSWEPGT_cam
16 SW_met graphs found