Keywords: monitoring land use Substances: 1-Hydroxy-Benzotriazole (ASOKPJOREAFHNY-UHFFFAOYSA-N) 2-4-D (OVSKIKFHRZPJSS-UHFFFAOYSA-N) 3-5-dibromo-4-hydroxybenzoic acid (PHWAJJWKNLWZGJ-UHFFFAOYSA-N)