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Parameters and sub-models for wet deposition of soluble and particulate contaminants to crops - RP0162

The proposed project will use the newly commissioned MAFF/CARE rain simulator (at Silwood Park, Ascot) to carry out a comprehensive series of experiments deriving high quality parameters relating to the interception and retention of contaminants in rain falling onto crop canopies. While limited data exists in the literature for this process, MAFF's existing modelling capability is restricted by the unavailability of data directly relevant ot the UK. The project will provide such data for different combinations of rainfall duration and intensity, generic crop type and growth stage/density, and contaminant chemistry. Building on the previous successful use of multivariate statistical analysis in predicting dry deposition parameters, similar statistical methods will be applied to the experimantal data to allow estimates to be made of wet deposition parameters for unexplored combinations of rainfall, canopy and contaminant types. Existing models will be tested against the data, and new compartmental model(s) proposed using derived statistical relationships as built-in parameter estimators. This research is expected to enhance very significantly MAFF's capability to predict the dose-to-man of radioactive contaminants depositing to crops in rainfall.
1. Identify which contaminants are of prime interest and which are likely to be soluble
2. Identify crop canopies covering a range of architectures
3. Develop techniques to ensure that particulates remain uniformly suspended in solution, and for measuring partitioning of contaminants
between solid and liquid phases
4. Identify representative UK rainfall characteristics, and develop exptl program to explore parameters important in interception of wet deposits
5. Determine interception as a function of rainfall parameters and biomass characteristics
6. Statistical analysis of data, and production of multivariate regression model
7. Test existing models and produce time compartmental sub-model for wet deposition (if necessary)
Time-Scale and Cost
From: 1996

To: 1999

Cost: £134,571
Contractor / Funded Organisations
University - London