Fire has variable but predictable effects on individual plants. Translating these from the physical to the physiological helps us
understand how fire affects vegetation not only at the level of the individual plant but also at the levels of the plant community and the landscape. Further, vegetation provides the fuel that makes fire possibles, so we can view fire effects on vegetation as an interaction rather than just a unidirectional effect. This chapter first describes mechanisms of fire damage to individual
plant parts. The differential response of plants may be due to fire variation or to specific adaptations of plants to survive as individuals. Some species with clear adaptations to fire may appear to increase the flammability of the community within which they grow but the issue of fire-dependent ecosystemsis a controversial topic on which debate is likely to continue. Also controversial, at least historically, has been the role of fire in plant succession theory. In recent years the emphasis has moved away from the development of all-encompassingt theories of vegetation development to the construction of process-orienteed ecological m odels.These dynamic models can incorporate fire as an ecological process. and several models applicable to the Pacific Northwest are conceptuallv described in this chapter. Such models have value in linking physlological processes of individual plantst to interactions at the community and landscapele levels.
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