Advances in

ECOLOGICAL RESEARCH

Edited by A. MACFADYEN

23 Mountsandel Road, Coleraine, Northern Ireland

E. D. FORD Centerfor Quantitative Science, University of Washington, 373715th Avenue

Seattle, Washington 98195, USA

VOLUME 17

1987

ACADEMIC PRESS Harcourt Brace Jovnnovich, Publishers

London Orlando San Diego New York Austin Boston

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