THE APPLICATION OF GIS TECHNIQUES TO ESTIMATE THE ESTABLISHMENT AND POTENTIAL SPREAD OF ARTIOPOSTHIA-TRIANGULATA IN SCOTLAND

The New Zealand flatworm (Artioposthia triangulata) has been shown to have the ability to become established throughout most of Scotland. It s possible spread to other countries has previously been predicted usi ng the CLIMEX model which uses only temperature and rainfall data. The application of Geographic Information System (GIS) techniques, includ ing soil pH and land use information, has allowed more detailed predic tions as to where A. triangulata could have the potential to have a de trimental effect on agricultural productivity and wildlife in Scotland . The results showed that acidic soil (pH < 4) probably restricts eart hworm, and hence New Zealand flatworm, distribution to only 36.6% of S cotland's land area. Further restrictions superimposed by lack of rain in eastern Scotland, and the distribution of arable / improved grassl and, meant that a relatively small al ea of Scotland's intensively far med land is probably at risk from A. triangulata and that the areas in volved were likely to be in the north east and west central Scotland. However the impact of A, triangulata on earthworm populations outside the arable/improved grassland areas has still to be assessed. The appl ication of GIS techniques using similar parameters and data from conti nental Europe should allow the areas that are at risk there to be more clearly identified.