Vertical Water Quality at Stationary PTs ?
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Water quality files with "WQP" are stationary samples at a single point where zooplankton + other metrics are collected. The timestamps don't match exactly with the GPS data (found in the files called ZoopChlW). It might be possible match the two using the date and site info found in the filenames or a fuzzy time match. It would be a many-to-one join since there is multiple water quality records for a single point.
The larger question is how is the WQP data used. The WQP data are vertical profiles that are used in the process to calibrate from the lab values. The SOP states that the values in the top meter of the water column are averaged in order to run a regression (see 1_WQp_Processing.R) but it is not clear if this is done for each reach individually or if the regression is applied to all data from that sampling day.
A couple of questions about the WQP data:
- Does the WQP data from the sonde need to be georeferenced by matching with the GPS data?
- Should the values be averaged for the top meter of the water column before being added to the database? This would make the table flat - ie one row per site per day.
The gain/validation samples are collected with GPS points. The points should be labeled by date and site with the tag WQP_x, where x= gain setting (ie, 0,1,10,100).
They are collected specifically where the zooplankton samples are taken, which are mostly at the same locations as the trawls. However some days (at low tides) they are moved downstream a bit to get enough water depth for a good zoop sample. The number of sites can be variable each day, ranging from 3 to around 13. The number of gain runs can vary from 3-4 as well (if we do 3, it is at 1, 10, 100).
We do need both the GIS point data, Site Name and the Water Quality Data (with corrected chl-a values) for comparison with the zoop samples.