Abstract. We present a methodology of how to use a top-level ontology to create a domain ontology from existing scientific texts by (1) identifying informal definitions of domain-specific terms, (2) substituting terms refering to top-level relations by terms of the top-level ontology, and (3) refining the definitions of the domain-specific terms by taking into account additional vocabulary provided by the top-level ontology. We demonstrate this methodology by applying it to Bailey's paper on `Delineation of Ecoregions'.