Time's moving fast. The samples for chemical analyses have arrived in Amsterdam and our valued colleague John Visser will do the analyses while we are here so that our students can start working with the results as soon as they are back in Holland. Thanks again John!!!
The focus of our measurements has now shifted to geophysics and determination of the permeability of soil, sand aquifers, and even Cretaceous clay.
In the morning we went on such a measurement campaign with Barry, Alexander, Frans and Rick - better known as the BARF group - and if the soil is not too permeable, life's easy.
Then something completey different! We installed the sapflow measurement system with Vicky, Margreet, Peter and Caroline. This allows hydrologists to determine the transpiration of trees, and therefore their water use. It involves drilling small holes in trees, installing sensors in the holes and then connecting these to a datalogger. Fortunately, it does not happen too often, but I made a mistake in programming te datalogger end we could not start the system until today, interrupting the groups geophysics activities... Sorry guys!
Then on to the next two groups, who used the Geonics EM-34 to assess the thickness of the Quaternary sands. This is an en easy and quick method to do so.
and there's always lots attention of the very kind Portuguese, who discuss our strange presence in their fields, and actually do depend on the water resources that we study for their agriculture.
Tomorrow: Excusion day to Colmeal with Jacob Keizer from the University of Aveiro...
