Field Notes

<--2003-08-30 10:00:00 | 2003-09-11 00:00:00-->

Tonzi/Vaira: 2003-09-05 04:30:00 (DOY 248)
Author: LiuKang Xu
Others:

Summary: Predawn water potential, Soil temperature and heat flux readings bad, lost some flux at Vaira

When: Sept 5 2003 D248
Where: Tonzi/Vaira Ranches
Who: Liukang Xu
Weather Sunny, little windy, temperature 85^oF. About 10% of oak leaves already senesced.

Problems for last weeks:

Almost everyday starting from d243, all soil temperature probes gave readings â€“6999 for about 5-7 hours. Also reading from soil heat flux plates was wrong. Need talk to Ted.

Predawn water potential measurements

		Tree #	Predawn potential (bar)
Date	DOY		1st leaf	2nd leaf	mean	std	Observer
9/5	248	245	-41.5	-44
9/5	248	248	-45.0	-46
9/5	248	250	-44.5	-41.5
9/5	248	252	-36.0	-48
9/5	248	255	-37.0	-36
9/5	248	231	-46.0	-45
9/5	248	241	-45.0	-44
9/5	248	NE of 245	-43.0	-47.5
9/5	248	242	-41.0	-38
9/5	248	240	-48.0	-44	-43.1	3.8	Liukang

Dendrometer reading:

	d248
date	9/5/2003
jday
time_pst	7:10
treetag
tree71	12.1
tree72	16.6
tree77	21.5
tree78	22.5
tree79	17

tree245	9.3
tree248	14.1
tree250	14
tree252	23.9
tree255	14.4

Observer	Xu

Soil moisture probe reading:

	Tonzi
	7931AFE	402165	574B4B	402FF3	57632	7A432E	7A3C6E	7A3B40	7A4AAA
	canopy	canopy	open	drip line	open
	tower	understory	solar panel	sap flow	resp trans
9/5/2003
0-15cm	5.80	4.00	9.10	2.23	7.77	6.37	5.70	5.10	0.90
15-30cm	12.33	12.93	11.20	11.30	13.20	6.10	11.40	9.90	1.30
30-45cm	17.13	5.00	13.53	12.20	1.90	8.43	12.73	15.30	11.40
45-60cm	11.83	5.93	11.30	8.90	9.07	10.30	6.67	15.85	8.20

	Vaira
	573FAA	7933FDE	operator
	open	open
	solar panel	flux tower
9/5/2003
0-15cm	2.40	4.40	Liukang
15-30cm	6.90	11.55
30-45cm	11.25	14.80
45-60cm	20.00	20.40

The battery voltage of the moisture probe was low, I brought back to the lab for charging.

Jianwuâ€™s soil CO2 probe reading good.

Jianwu's CO2 probe
open space	Undercanopy
430 ppm	830 ppm
630 ppm	1640 ppm
0.10%	2960 ppm
	0.46%

Tower fence and flux systems running good. Sonic outputs

	mean	std		mean	std
w	0.07	0.255	Tsonic	23.063	0.161
u	-0.49	0.171	q	2.652	0.013
v	-1.24	0.164	CO2	1.556	0.009

Floor system:

2 extra pc208w windows (real-time connection and hard-ware connection) were left open, so the flux system was running about 2/3 of the time for the last week.