Population dynamics

摘要: Studies of forest insect population dynamics have generally taken two approaches, using either long-term life-table data from a single forest stand or data from several widely separated sites where each site is treated as a replicate population and a composite picture of the dynamics is inferred from the multiple sties. Examples of the former include studies of the winter moth, Operophtera brumata, in Wytham Wood (Varley and Gradwell, 1968) and larch casebearer, Coleophora laricella (Ryan, 1990); examples of the latter include studies of the gypsy moth, Lymantria dispar (Campbell, 1973), and the spruce budworm, Choristoneura funniferana (Mott, 1963; Royama, 1984). By considering dynamics at only a single site, or at multiple but distant sites, these studies eliminate potentially eritical elements of animał population dynam-ics: the effect of dynamics at neighboring sites, movement among sites, and how the …