Periodically forced food-chain dynamics: model predictions and experimental validation.
Despite the recognition of the importance of seasonal forcing in nature, remarkably few studies have theoretically explored periodically forced community dynamics. Here we employ a novel approach called "successional state dynamics" (SSD) to model a seasonally forced predator-prey system. We first generated analytical predictions of the effects of altered seasonality on species persistence and the timing of community state transitions. We then parameterized the model using a zooplankton-phytoplankton system and tested quantitative predictions using controlled experiments. In the majority of cases, timing of zooplankton and algal population peaks matched model predictions. Decreases in growing-period length delayed algal blooms, consequently delaying peaks in zooplankton abundance. Predictions of increased probability of predator extinction at low growing-period lengths were also upheld experimentally. Our results highlight the utility of the SSD modeling approach as a framework for predicting the effects of altered seasonality on the structure and dynamics of multitrophic communities.
Steiner
Christopher F
CF
Department of Biological Sciences, Wayne State University, Detroit, Michigan 48202, USA. csteiner@wayne.edu
Schwaderer
Anne S
AS
Huber
Veronika
V
Klausmeier
Christopher A
CA
Litchman
Elena
E
D000818:Animals; D016825:Chlamydomonas reinhardtii / Q000502:physiology; D020387:Food Chain; D008954:Models, Biological; D010839:Phytoplankton / Q000502:physiology*; D011157:Population Dynamics; D011235:Predatory Behavior; D012403:Rotifera / Q000502:physiology; D012621:Seasons; D013997:Time Factors; D015048:Zooplankton / Q000502:physiology*