Citation:
Fabrice G. Renaud, Pat H. Bellamy, Colin D. Brown, Simulating pesticides in
ditches to assess ecological risk (SPIDER): I. Model description, Science of The
Total Environment, Volume 394, Issue 1, 1 May 2008, Pages 112-123
Abstract:
Risk assessment for pesticides in the aquatic environment relies on a comparison
between estimated exposure concentrations in surface water bodies and endpoints
from a series of effect tests. Many field- and catchment-scale models have been
developed, ranging from simple empirical models to comprehensive, physically-
based, distributed models that require complex parameterisation, often through
inverse modelling methods. Routine use of catchment models for assessment and
management of pesticides requires a tool that is comprehensive in being able to
address all major routes of entry of pesticides into surface water and that has
reasonable parameter requirements. Current models either focus primarily on
transport of pesticides in surface runoff or are restricted in application
because they require calibration against data from detailed monitoring
programmes. SPIDER (Simulating Pesticides In Ditches to assess Ecological Risk)
was developed to address the gap in models available to simulate pesticide
exposure within networks of small surface water bodies (ditches and streams) in
support of ecological risk assessment for pesticides. SPIDER is a locally
distributed, capacitance-based model that accounts for pesticide entry into
surface water bodies via spray drift, surface runoff, interlayer flow and
drainflow and that can be used for small agricultural catchments. This paper
provides a detailed description of the model.