Repellents Preventing Hoofed Game Browsing Can Alter the Mobility of Nutrients in Soil

Abstract

To protect forest cultures against browsing, chemical repellents can be used. With their applications, however, a problem arises with disruption of biological and chemical equilibria in the environment (e.g., soil-plant system). The aim of this study were to assess possible interactions of repellents, denatonium benzoate (DB), and capsaicin (Cps), with the soil matrix, especially the impact of their addition on the mobility of individual micronutrients and macronutrients, such as calcium, copper, iron, magnesium, manganese, phosphorus, sulfur, and zinc, and to verify the hypothesis that the presence of repellent compounds does not affect the plant-available nutrient concentrations in soil. Batch laboratory soil sorption experiment and the “diffusive gradient in thin films” (DGT) technique were applied to evaluate the elements’ mobility in the soils. Sorption experiment using Chernozem and Fluvisol showed decreased mobile forms of Cu and S with the additions of both repellents and conversely increased mobile forms of Ca and Mn for DB, in both soil types. With increasing Cps rates, the mobile forms of Fe in Chernozem decreased and Mn in Fluvisol increased. The DGT experiment confirmed increased mobile/available Mn in both soils for both repellents and Fe in Fluvisol in the case of capsaicin. Soil application of both, DB and Cps, suggested to be able to influence the elements’ mobility, particularly, Mn mobility in soil significantly increased after repellent application. Their possible behavior in rhizosphere soil/soil solution should be investigated in further research.