Field Notes

<--2023-04-14 14:00:00 | 2023-05-16 12:10:00-->
Other sites visited today: Vaira | Bouldin Corn

Tonzi: 2023-04-26 11:20:00 (DOY 116)
Author: Joe Verfaillie
Others: Sophie, Megan

Summary: Trees fully leafed out, tree survey by Sophie and Megan, added calkit to the Floor, new hats for FD chambers, drying out.

Tonzi
2023-04-26

Sophie, Megan and I arrived at about 11:20 PDT. It was clear sunny and warm with a breeze from the south. Megan and Sophie are here to do a tree survey measuring the DBH of the trees with bands. They are also taking photos of the trees. The trees seem close to fully leafed out although some still are the lighter green of fresh leaves. The ground is dry except for the very low places. On the way in from Sacramento we could see small places where the grass was turning brown. There were lots of small mosquitos in the shady places.

I got Megan and Sophie oriented with the tree bands and then did the standard fieldwork. I added a calkit to the Floor met system to measure RH/Temp and test an old Licor pressure sensor sn K993237 (?) using a CR1000 sn 4190. I added a ventilated HML155 sn T2930114 to the post with the existing HMP45. I wanted to add Carlos’s reverse Bowen measurements to all the met systems here and at Vaira but it was a bigger task than I thought. I decided I should work on the programs in the lab.

The Tower was okay, IRGA seemed fine. There were lots of spider webs on the eddy sensors so I lowered them and cleaned them off. The radiometers looked clean. The Floor 23X is still having communications problems. The serial wires have some chew marks but I could connect with it using the laptop, so I think it’s the Multiport serial box that is having problems. I tried different ports on it but I seem to remember the port numbers weren’t assigned in order. I collected the Floor data directly from the 23x with the laptop.

The tower Read: 425.9ppm CO2, 429.2mmol/m3 H2O, 23.2C, 99.0kPa, 103.1SS
The Floor read: 421.2ppm CO2, 493.8mmol/m3 H2O, 25.8C, 99.1kPa, 98.8SS
Humidity seem to be rising quickly - later Vaira was 610mmol/m3.

I measured the wells – water level came up a lot; I could see the water in the Floor well. The old laptop for the Road Well almost didn’t work. I need to make sure the lithium power pack is freshly charged I think. I read the dendrometers, did the soil moisture measurements and serviced the z-cams. I need to bring the leaf water potential stuff next time.

I added new plastic and mirrored Mylar hats to the FD chambers and collected their data. The one under the trees still does not have a sun shield on its body.

I went to Vaira about 14:30 while Megan and Sophie continued measuring trees. I returned about 16:10 to collect a few last data sets while Sophie and Megan climbed the tower.

We left at about 16:30 PDT

Field Data

No tank data

Well Depth

Date	Location	Depth (feet)
2023-04-26	TZ_floor	15
2023-04-26	TZ_road	23.88
2023-04-26	TZ_tower	18.4
2023-04-26	VR_well	47.1
2023-04-26	VR_pond	21.08

No TZ Moisture Point data found

No VR Moisture Point data found

No TZ grass heigth found

Grass Height VR 10

Date	Height reps (cm)										Location	Average	Samp	STDEV
2023-04-26	51	28	36	25	15	23	23	20 33	25	33	GH_ALL	27.9	10	9.59

Tree DBH

Date	Tag#	Reading (mm)
2023-04-26	1	12.5
2023-04-26	102	3.9
2023-04-26	2	4.7
2023-04-26	245	6.7
2023-04-26	3	4.9
2023-04-26	4	6.9
2023-04-26	5	12.8
2023-04-26	6	5.7
2023-04-26	7	13.8
2023-04-26	72	17.2
2023-04-26	79	19.2