Field Notes

<--2020-05-01 11:40:00 | 2020-05-19 13:15:00-->

West Pond: 2020-05-09 09:10:00 (DOY 130)
Author: Ariane Arias-Ortiz
Others: It, Roc

Summary: Monthly surface and porewater sampling

It was a sunny day with no clouds and no wind. Roc and I arrived at WP at 9:10 am, the visit was to sample surface waters and porewaters after the wetland has been inundated again.

The water level at the tower was 43 cm. The inlet was closed and there was no water flowing downstream through the outlets. The east outlet, however, leaks a little bit. Boards at the outlets were high, the window left for water to flow through is 2.5 and 9.7 cm at east and west outlets respectively. Distance from top of the boards to the water level was 22 cm upstream, and 30 cm downstream at the east outlet. Distance to water level was 17.5 cm and 24 cm upstream and downstream, respectively at the west outlet.

We sampled surface waters at the tower, 0.5 and 0.85 footprint sites and inlet and outlet locations. Although the staff gauge water level was 43 cm, the depth of standing water inside the wetland was much lower. It was about 5 cm at the 0.5 footprint, it was negligible between the 0.7 and 0.8 footprint areas, and it was about 15-20 cm at the 0.85 footprint site. Seems that soil elevation increases towards the center and decreases towards the edges of the wetland, which agrees with soil accumulation rates estimated with Pb-210. Surface water conductivity averaged 303 uS/cm, salinity 0.19 ppt, pH 6.51 and DO: 2 mg/L.

Readings at the tower were:
Conductivity: 243 uS
Salinity; 0.16 ppt
pH:6.6
DO: 2.7 mg/L
Temp: 14.4 C

Porewaters were sampled at -10, -30 and -50 cm in all sites, except for the 0.5 footprint site where the -20 and -40 depths were also included. Conductivity and salinity increased with depth from about 300 to 650 uS (0.2 to 0.4 ppt) while pH and dissolved oxygen decreased with depth from about 6.5 to 6 (2 to 0.113 mg/L).

The sedpoints worked well at all sites. I need to bring more tubing for WP5_PW10 and clean WP7_PW50 next time.

We left at 2 pm.

1 photos found

WP_autocam_20200508_1845.jpg ( 2020-05-08 18:45:03 ) Full size: 1920x1440
Nice sunset