Variables: total_organic_carbon pH Keywords: land use Substances: 2-n-Octyl-4-isothiazolin-3-on (OIT) (JPMIIZHYYWMHDT-UHFFFAOYSA-N) 4-Aminopyrin (4-Aminoantipyrin 4-AA) (RLFWWDJHLFCNIJ-UHFFFAOYSA-N)