Sensitivity of the population growth rate to demographic variability within and between phases of the disturbance cycle

W. F. Morris, S. Tuljapurkar, C. V. Haridas, E. S. Menges, Carol C Horvitz, C. A. Pfister

Research output: Contribution to journalArticle

22 Scopus citations


For species in disturbance-prone ecosystems, vital rates (survival, growth and reproduction) often vary both between and within phases of the cycle of disturbance and recovery; some of this variation is imposed by the environment, but some may represent adaptation of the life history to disturbance. Anthropogenic changes may amplify or impede these patterns of variation, and may have positive or negative effects on population growth. Using stochastic population projection matrix models, we develop stochastic elasticities (proportional derivatives of the long-run population growth rate) to gauge the population effects of three types of change in demographic variability (changes in within- and between-disturbance-phase variability and phase-specific changes). Computing these elasticities for five species of disturbance- influenced perennial plants, we pinpoint demographic rates that may reveal adaptation to disturbance, and we demonstrate that species may differ in their responses to different types of changes in demographic variability driven by climate change.

Original languageEnglish
Pages (from-to)1331-1341
Number of pages11
JournalEcology Letters
Issue number12
StatePublished - Dec 1 2006



  • Climate change
  • Demographic variability
  • Disturbance
  • Elasticity
  • Fire
  • Life-history adaptation
  • Long-run stochastic growth rate
  • Markov transition matrix
  • Population projection matrix

ASJC Scopus subject areas

  • Ecology

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