The thesis presents a series of principles, similar to those developed by the Organisation for Economic Co-operation and Development in relation to policy oriented indicators, intended to codify best-practice with regards to the design of pesticide risk indicators for use by farmers. Development of these principles was based upon extensive reviews of the literature concerning the potential exposure to and impacts of pesticides on non-target organisms and the relative merits and limitations of different methodological approaches, discussions with farmers concerning the suitability of different approaches to risk indicators and experimental assessments of indicator performance. These assessments took the form of a three-year field trial examining the impact of different levels of pesticide input upon non-target arthropods and several smaller trials that compared the performance of different insecticides and investigated the effect of differences in pesticide dose on non-target arthropods. The data were then compared with the theoretical results generated by a number of different risk indicators. The thesis also identifies a number of barriers to the implementation of these principles in the form of new pesticide risk indicators. These include restrictions on the range of non-target organisms and potential effects for which high quality data is available and the methodological difficulties associated with the incorporation of sublethal, indirect and ecosystem-level effects into risk indicators. Improvements in the validation of pesticide risk indicators that enable objective evaluations of indicator performance to be made are also required.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:509210 |
Date | January 2009 |
Creators | Parnaby, Susannah |
Publisher | University of Aberdeen |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=56257 |
Page generated in 0.0013 seconds