Plynlimon research catchment hydrochemistry (2016-2019)

Sampling was carried out fortnightly from March 2016 to July 2017. From August 2017 to November 2018 stream samples were collected every four weeks and the rain sample every two weeks. From December 2018 onwards samples were collected every four weeks. Stream samples were taken using a grab technique. Rain samples were collected using bulk precipitation collectors. Stream flow is calculated from dip measurements taken at the time of sampling. Standard rainfall collectors are used to measure rainfall volume.

Upon return to the CEH Bangor laboratories the cation samples were acidified with concentrated Nitric Acid (to 1 percent) to preserve the samples. Samples for anion and cation sample were then stored at 4 degrees Celsius until they could be transported to the Centralised Analytical Chemistry Group in CEH Lancaster for analysis. Results were reported back to CEH Bangor as Excel spreadsheets. These data were then imported into an Access database.

pH, conductivity and alkalinity analysis was carried out the CEH Bangor laboratories. Results were reported back as Excel spreadsheets. Field measurements and flow calculations were also added to these Excel spreadsheets. These data were then imported into the same Access database as the CEH Lancaster results.

For ingestion into the Environmental Information data was extracted from the Access database and converted into a comma separated value file.