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Demographic consequences of changes in environmental periodicity
Eva Conquet1, Arpat Ozgul1, Daniel T Blumstein2,3
1Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
Ecology
|October 8, 2022
Summary
Periodic environmental changes significantly impact population dynamics across diverse species. Understanding these shifts is crucial for predicting population viability amid global environmental change.
Area of Science:
- Ecology
- Population Biology
- Environmental Science
Background:
- Population dynamics are influenced by vital rates, which can vary randomly year-to-year or periodically.
- While random variation is well-studied, the impact of periodic, nonrandom vital rate changes, like seasonality, is less understood.
- Global environmental change may alter these periodic variations, posing risks to natural populations.
Purpose of the Study:
- To investigate how altered vital-rate periodicity affects population dynamics.
- To examine species with different adaptations to periodic environments: yellow-bellied marmots, meerkats, and dewy pines.
- To assess the impact of perturbing periodicity strength on population growth metrics.
Main Methods:
- Parameterized periodic matrix population models for three distinct species.
- Projected population dynamics under various scenarios of altered vital-rate periodicity.
- Analyzed effects on population metrics, including the stochastic growth rate (log λS).
Main Results:
- Perturbing periodicity strength significantly affected population dynamics in all studied species.
- Increased seasonal variation in marmot survival decreased population growth.
- Density dependence buffered meerkats and dewy pines from some periodicity perturbations, depending on disturbance frequency.
Conclusions:
- Changes in vital-rate periodicity strength have diverse but substantial effects on population dynamics across different life histories.
- Periodic environmental patterns are critical for population viability, especially for species not buffered against inter-annual variation.
- Future global change research must incorporate the effects of altered periodic environmental variations on population dynamics.
Keywords:
fire regimesmatrix population modelperturbationpopulation viability analysisseasonalityvital-rate periodicityMore Related Videos
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