Field Notes

<--2024-04-04 08:45:00 | 2024-04-16 14:15:00-->
Other sites visited today: Mayberry | West Pond | East End

Gilbert Tract: 2024-04-11 08:15:00 (DOY 102)
Author: Daphne Szutu
Others: Kyle, Gelary, Ash

Summary: Visitors Gelary and Ash, CTD not working--needs replacement, RH/T data missing--fixed, knocked down wasp nests, saw an otter

2024-04-11
Gilbert Tract

Kyle, Gelary, and I arrived at 8:15 PST (9:15 PDT). Gelary is an undergraduate who is planning to do soil/plant chamber measurements for her senior thesis. At the gate, we met Ash, a wetland modeler from LBL working with the UC Labs Wetlands project. It was a mild morning, sunny with a cool breeze and only a few cirrus clouds. It will warm up to 30C (85F) later.

The wetland is continuing to green up, with some tules encroaching onto the side of the levee. The staff gauge read 76cm at 8:58 PST. Kyle, Gelary, and Ash measured the surface water conductivity off of the pier.
Surface, 310uS, 16.5C

I downloaded met, cam, and USB GHG data. Kyle cleaned flux and rad sensors and topped off the wash reservoir. I moved the Song Meter Micro files to my field laptop. I connected via mobile app and there was a popup to sync location. The location should have been set up last time, so I'm not sure why there a popup today. I agreed to sync the location, and I checked that the recorder time matched my phone time (local time).

The CTD sensor has not been working for the past week. It also took down the Hygrovue RH/T sensor at the same time, since both were connected to C7. I disconnected the Hygrovue so that only the CTD was wired to C7. I cycled its power and tried to talk to it on the CR1000 terminal emulator, but wasn't getting any response. I removed the CTD from C7 and reattached the Hygrovue (can't remember if I left the CTD powered). The RH/T data looked reasonable. I didn't bring waders today so I left the CTD in the water for now. I could install the CTD from Hill Slough (the EXO there also measures conductivity, temperature, and nonvented depth).

The 7500 read: 465ppm CO2, 692mmol/m3 H2O, 21.2C, 101.4kPa, 102SS—104 after cleaning
The 7700 read: 2.2ppm CH4, 49RSSI – 86 after cleaning

Gelary experimented with one of the green PVC chamber collars and the clippers, seeing how easy (or not) it is to create a good seal between the collar and the dry ground on the edge of the wetland. The current plan is to gently clear the litter from the ground, press the collar into the soil, cut the reeds, and quickly place the chamber on top. We'll play around with the analyzer/chamber in the lab before we try it in the field.

Ash asked a bunch of questions about the different types of data that were available. He usually uses the Ameriflux FLUXNET data product and wasn't aware that water salinity was available in the Ameriflux BASE data. We also talked about how the soil temperature and water temperatures were relative to the soil "surface," and all the issues there. He was also curious if too much sun can damage the leaves (I don't think we see that here?) and if we had any water nitrate data. I'll look into the 24hr sampling campaigns and get back to him.

There were two small wasps nests underneath the middle boardwalk. Before we left, I chased away the wasps with the pump sprayer and knocked the nests to the ground.

We saw a small otter scampering along the rocks lining the channel east of our tower.

We got to the channel at 9:40 PST. I stopped data collection, set the clock from the Utilities menu (there was no popup this time), downloaded the data files, and restarted logging. There were 3 data files total, one of which said "partially downloaded." All of the data seemed to be in the latest file so I think I can delete the other two files. While at the channel, we heard a sound like water glugging in a big pipe, or a pool skimmer/weir door opening and closing. We excitedly looked for large animals in the channel, but didn't see anything obvious. So maybe something to do with the irrigation system.

We left at 9:53 PST (10:53 PDT).

Looking at the data back in the lab, the last photo was from 2024-04-02. I ran Recuva but it didn't come up with anything new. I reformatted the card.

0 photos found

7 sets found

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