Variables: total_organic_carbon Keywords: land use Substances: 4-Aminopyrin (4-Aminoantipyrin 4-AA) (RLFWWDJHLFCNIJ-UHFFFAOYSA-N) Acetochlor-ESA (HXAIQOCRALNGKB-UHFFFAOYSA-N) 2-Methyl-4-isothiazolin-3-one (BEGLCMHJXHIJLR-UHFFFAOYSA-N)