An agent-based model that simulates the spatio-temporal dynamics of sources and transfer mechanisms contributing faecal indicator organisms to streams. Part 2: Application to a small agricultural catchment

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:270

Article

Neill, Aaron J.^1,2  Tetzlaff, Doerthe^1,3,4  Strachan, Norval J. C.⁵  Hough, Rupert L.²  Avery, Lisa M.²  Maneta, Marco P.^6,7  Soulsby, Chris^1,3 

[1] Univ Aberdeen, Northern Rivers Inst, Aberdeen AB24 3UF, Scotland

[2] James Hutton Inst, Aberdeen AB15 8QH, Scotland

[3] IGB Leibniz Inst Freshwater Ecol & Inland Fisheri, D-12587 Berlin, Germany

[4] Humboldt Univ, Dept Geog, D-10099 Berlin, Germany

[5] Univ Aberdeen, Sch Biol Sci, Cruickshank Bldg,St Machar Dr, Aberdeen AB24 3UU, Scotland

[6] Univ Montana, Geosci Dept, Missoula, MT 59812 USA

[7] Univ Montana, WA Franke Coll Forestry & Conservat, Dept Ecosyst & Conservat Sci, Missoula, MT 59812 USA

关键词: Diffuse pollution;    E. coli;    EcH(2)O-iso;    Microbial water quality;    Tracer-aided modelling;    Water quality modelling;   

DOI  :  10.1016/j.jenvman.2020.110905

来源: Elsevier

【 摘 要 】

The new Model for the Agent-based simulation of Faecal Indicator Organisms (MAFIO) is applied to a small (0.42 km(2)) Scottish agricultural catchment to simulate the dynamics of E. roll arising from sheep and cattle farming, in order to provide a proof-of-concept. The hydrological environment for MAFIO was simulated by the best ensemble run of the tracer-aided ecohydrological model EcH(2)O-iso, obtained through multi-criteria calibration to stream discharge (MAE: 1.37 L s(-1)) and spatially-distributed stable isotope data (MAE: 1.14-3.02 parts per thousand for the period April December 2017. MAFIO was then applied for the period June August for which twice-weekly E. coli loads were quantified at up to three sites along the stream. Performance in simulating these data suggested the model has skill in capturing the transfer of faecal indicator organisms (FIOs) from livestock to streams via the processes of direct deposition, transport in overland flow and seepage from areas of degraded soil. Furthermore, its agent-based structure allowed source areas, transfer mechanisms and host animals contributing FIOs to the stream to be quantified. Such information is likely to have substantial value in the context of designing and spatially-targeting mitigation measures against impaired microbial water quality. This study also revealed, however, that avenues exist for improving process conceptualisation in MAFIO (e.g. to include FIO contributions from wildlife) and highlighted the need to quantitatively assess how uncertainty in the spatial extent of surface flow paths in the simulated hydrological environment may affect FIO simulations. Despite the consequent status of MAFIO as a research-level model, its encouraging performance in this proof-of-concept study suggests the model has significant potential for eventual incorporation into decision support frameworks.

【 授权许可】

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