the active or passive movement of individual plants or animals or their disseminules (such as seeds, spores and lavrae) into or out of a population or population area. It includes emigration, immigration and migration.
... the risk of spread of the harmful organisms held under quarantine containment conditions shall be determined by the responsible official body, having regard to the type of material and the activity envisaged, and to the biology of the harmful organisms, the means of their dispersal, the interaction with the environment and other relevant factors relating to the risk posed by the material concerned.
