Agricultural activities have the potential to increase dramatically the concentrations of nutrients into water courses.

A recent study by Luode Consulting demonstrated the importance of continuous monitoring of phosphate concentrations using our THOË sampler containing DGT devices with an iron oxide binding layer (LSNP-NP) in a small creek downstream of farmland.

The THOË automatic sampler was programmed to exposed DGT devices over twelve 24-hour periods. To demonstrate this innovative technique provided an improvement over traditional sampling, several spot samples were collected and analyzed using classical colorimetric determination by CFA (Continuous Flow Analysis).

THOË’s integrated temperature logger was used to record water temperatures over the study period (0.2-6.5°C) to allow accurate determination of the daily dissolved phosphate concentrations.

During the study period the THOË autosampler permitted the identification of a severe pollution event with phosphates concentrations reaching over 10 times the lowest values recorded. The pollution event was traced back to a manure being cleaned out of a cow house.

Daily phosphate  concentrations

determined in a small creek using

a THOË sampler