Variables: total_organic_carbon Keywords: land use Substances: 4-Formylaminoantipyrin (4-FAA) (WSJBSKRPKADYRQ-UHFFFAOYSA-N) 18-beta-Glycyrrhetinic acid (MPDGHEJMBKOTSU-YKLVYJNSSA-N) 5-Chloro-2-methyl-4-isothiazolin-3-on (CMI) (DHNRXBZYEKSXIM-UHFFFAOYSA-N)