Field Notes

When: Aug. 29, 2002 D241
Where: Tonzi/Vaira Ranches
Who: Liukang Xu
Weather Sunny, temperature lower 90s, comfortable.

Trip Purpose: predawn water potential measurement, check 3 flux systems and download data, soil moisture probe reading, dendrometer reading, A/C_i curve for oak leaf at Tonzi Ranch, replace batteries for Nancy’s sap flow.

Overall: Floor system was down for the last week (see below for reason) ! Tower and Vaira flux systems and other instruments running good, Jianwu’s soil CO2 sensors OK. Leaves already started senescence, lot of trees have more than half of the leaves turned brown.

Tonzi Ranch: arrived at 4:50am. Clear sky, temperature 56F

Predawn water potential reading:

Dendrometer reading at 6:30 am

Soil moisture probe reading:

Tower Flux system: Fence and sonic program OK. PV reading 12.3, 5.7, 2.0 at 8:45am. After download data, reboot pc, gillsonic output for w u v Tsonic, q and Co2 on scale.

Floor Flux system: Fence OK. Flux program was minimized, PC208W was also hang up. No flux data and no communication between pc and all the data-loggers last week. After reboot pc, I found the gillsonic.exe was turned on before PC208W. then after 2 min there is another gillsonic turned on by pc208. That is the problem. In the startup menu, there is gillsonic.exe and PC208W.exe. I deleted gillsonic.exe.

Also the subdirectory c:Tonzi, where all the met soil and sapflow data files located, was moved to c:\Programms\Tonzi, so the pc208w can not find c:\Tonzi, it gave me error message on pathway of subdirectory.

After I deleted gillsonic.exe in the startup move and move the Tonzi back to under C:\, the flux system and pc communication with dataloggers were good .

PV reading 13.4, 7.5, 1.8 with fully charged battery.

Vaira Ranch: arrived at 7:30, Fence Ok, flux system also running great last week. PV reading 12.3, 1.8, and 1.8 at 7:50 with half fully charged battery. Soil moisture probe reading (see above). Sonic outputs looks Ok after finished all the tasks.