Yesterday I installed access tubes (e.g., piezometers) at
various locations among low- and high-centered polygons, placing them in dry
edges and wet, saturated troughs. They were also installed to several depths
from the upper organic layer to near the permafrost table. Today I returned to those
and used a syringe to extract a sample of water. The water tends to be full of
sediment, but these samples will be filtered prior to analysis back in the
laboratory. Surface water samples were collected as well for comparison and
they contained far less suspended sediments than the pore water samples.
Baohua, David Graham, and several others from ORNL will
return in late August to collect another set of samples. Patterns of
geochemistry over the season and across years will help us to understand controls on
methane production and improve the way these processes are represented in
models.
