The Svalbard Intertidal Zone: A Concept for the Use of GIS in Applied Oil Sensitivity, Vulnerability and Impact Analyses K. A. MOE *, G. M. SKEIE , O. W. BRUDE , S. M. LéV  ASà, M. NEDREBé§ & J. M. WESLAWSKI    Alpha Environmental Consultants Ltd, Kongens gate 9, 0153 Oslo, Norway àSINTEF Civil and Environmental Engineering, Trondheim, Norway §Municipality of Sandnes, Sandnes, Norway   Arctic Ecology Group, Institute of Oceanology PAS, Sopot, Poland Historical oil spills have shown that environmental damage on the seashore can be measured by acute mortality of single species and destabilisation of the communities. The biota, however, has the potential to recover over some period of time. Applied to the understanding of the fate of oil and population and community dynamics, the impact can be described by the function of the following two factors: the im- mediate extent and the duration of damage. A simple and robust mathematical model is developed to describe this process in the Svalbard intertidal. Based on the integral of key biological and physical factors, i.e., community speci®c sensitivity, oil accumulation and retention capacity of the substrate, ice-cover and wave exposure, the model is implemented by a Geographical Information System (GIS) for characteri- sation of the habitatÕs sensitivity and vulnerability. Geomorphologic maps and georeferenced biological data are used as input. Digital maps of intertidal zone are compiled, indicating the shoreline sensitivity and vulnerability in terms of coastal segments and grid aggregations. Selected results have been used in the national assessment programme of oil development in the Barents Sea for priorities in environmental impact assessments and risk analyses as well as oil spill contingency planning. Ó 2000 Elsevier Science Ltd. All rights reserved. Introduction Oil can cause acute biological eects directly, by its chemotoxicology or by mechanical stress when or- ganismsÕ habitat is chemically and physically disturbed or altered so that vital functions such as photosyn- thesis, enzyme and nervous systems, food consump- tion, reproduction and behaviour are inhibited. Organisms not aected directly can be indirectly sub- jected to impacts by changes in community structure and co-existence interactions such as grazing, preda- tion and competition dynamics. Increased mortality of individuals, reduced diversity and destabilisation of the communities, are apparently the most dramatic eects of shoreline oil contamination. Ultimately, decimation of the communities and denuded sub- strate are demonstrated in local areas most heavily aected (Southward & Southward, 1978; Sanders et al., 1980; Conan, 1982; Stekoll et al., 1993; Hol- loway, 1996). However, many organisms have developed adaptive responses to neutralise or counteract the impact of oil pollution at dierent organisation levels. The oil ashore is also subjected to a variety of weathering processes that gradually reduce its bioavailability. Consequently, in parallel to the degradation of oil, and via ecological succession mechanisms, the shore 187 Spill Science & Technology Bulletin, Vol. 6, No. 2, pp. 187±206, 2000 Ó 2000 Elsevier Science Ltd. All rights reserved. Printed in Great Britain 1353-2561/00 $ - see front matter PII: S1353-2561(00)00038-4 *Corresponding author. Tel.: +47-22-42-05-30; fax: +47-22-42-15- 11. E-mail address: alpha@alphaenv.com (K.A. Moe).