New LovoTECS resources are now available on Youtube. We've added 3 training videos.
Oakton EC Testr Calibration Video
Oakton EC Testr 11+ Battery Change
Onset Hobo U24 and U20 Changing Time Interval
Saturday, November 17, 2012
A pattern that is emerging around New Hampshire is that specific electrical conductance is highest at low flows and becomes diluted as flows increase. This is because there are higher solute concentrations in soil water or groundwater and lower solute concentrations in rainwater. Higher solute concentrations in groundwater or soil water are partly natural, caused by dissolution of naturally occurring minerals. However, sometimes higher solute concentrations are elevated by human inputs of minerals, particularly sodium chloride as road salt. Natural or human-caused, this dilution pattern can tell us about how much groundwater contributes to a stream. But, I will leave this discussion to Ashley Hyde for another time. In the meantime, here is a picture of dilution from a downstream reach of the Israel River (or Israel's River). I am writing code to produce these pictures for each site, and this is the first picture I've been able to pull together. I was excited, so I thought I would share.
Posted by Mark Green at 2:18 PM
Monday, November 12, 2012
We are building computer code (R is our preferred scripting language) to summarize the huge amounts of data arriving from the LoVoTECS sensors. We are going to publish graphs here to share interesting patterns in the data. Here are a few months.
There is a clear positive relationship between monthly median water temperature and specific electrical conductance. Our warmer streams have more solutes in them - the role human activities play in driving this pattern is a future question that we will be addressing.
Posted by Mark Green at 8:57 PM