TY - JOUR

T1 - Modeling the environmental fate of bracken toxin ptaquiloside

T2 - Production, release and transport in the rhizosphere

AU - García-Jorgensen, Daniel B.

AU - Holbak, Maja

AU - Hansen, Hans Chr. Bruun

AU - Abrahamsen, Per

AU - Diamantopoulos, Efstathios

N1 - Publisher Copyright: © 2024 The Authors

PY - 2024

Y1 - 2024

N2 - Plants produce a diverse array of toxic compounds which may be released by precipitation, explaining their wide occurrence in surrounding soil and water. This study presents the first mechanistic model for describing the generation and environmental fate of a natural toxin, i.e. ptaquiloside (PTA), a carcinogenic phytotoxin produced by bracken fern (Pteridium aquilinum L. Kuhn). The newly adapted DAISY model was calibrated based on two-year monitoring performed in the period 2018–2019 in a Danish bracken population located in a forest glade. Several functions related to the fate of PTA were calibrated, covering processes from toxin generation in the canopy, wash off by precipitation and degradation in the soil. Model results show a good description of observed bracken biomass and PTA contents, supporting the assumption that toxin production can be explained by the production of new biomass. Model results show that only 4.4 % of the PTA produced in bracken is washed off by precipitation, from both canopy and litter. Model simulations showed that PTA degrades rapidly once in the soil, especially during summer due to the high soil temperatures. Leaching takes place in form of pulses directly connected to precipitation events, with maximum simulated concentrations up to 4.39 μg L−1 at 50 cm depth. Macropore transport is mainly responsible for the events with the highest PTA concentrations, contributing to 72 % of the total mass of PTA leached. Based on the results, we identify areas with high density of bracken, high precipitation during the summer and soils characterized by fast transport, as the most vulnerable to surface and groundwater pollution by phytotoxins.

AB - Plants produce a diverse array of toxic compounds which may be released by precipitation, explaining their wide occurrence in surrounding soil and water. This study presents the first mechanistic model for describing the generation and environmental fate of a natural toxin, i.e. ptaquiloside (PTA), a carcinogenic phytotoxin produced by bracken fern (Pteridium aquilinum L. Kuhn). The newly adapted DAISY model was calibrated based on two-year monitoring performed in the period 2018–2019 in a Danish bracken population located in a forest glade. Several functions related to the fate of PTA were calibrated, covering processes from toxin generation in the canopy, wash off by precipitation and degradation in the soil. Model results show a good description of observed bracken biomass and PTA contents, supporting the assumption that toxin production can be explained by the production of new biomass. Model results show that only 4.4 % of the PTA produced in bracken is washed off by precipitation, from both canopy and litter. Model simulations showed that PTA degrades rapidly once in the soil, especially during summer due to the high soil temperatures. Leaching takes place in form of pulses directly connected to precipitation events, with maximum simulated concentrations up to 4.39 μg L−1 at 50 cm depth. Macropore transport is mainly responsible for the events with the highest PTA concentrations, contributing to 72 % of the total mass of PTA leached. Based on the results, we identify areas with high density of bracken, high precipitation during the summer and soils characterized by fast transport, as the most vulnerable to surface and groundwater pollution by phytotoxins.

KW - Bracken fern

KW - Mechanistic model

KW - Ptaquiloside

KW - Toxin leaching

KW - Toxin production

U2 - 10.1016/j.scitotenv.2024.170658

DO - 10.1016/j.scitotenv.2024.170658

M3 - Journal article

C2 - 38340825

AN - SCOPUS:85185809249

VL - 921

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

M1 - 170658

ER -