Article

Patch Dynamics and Metapopulation Theory: the Case of Successional Species

National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, 735 State Street, Suite 300, Santa Barbara, CA, 93101-5504, U.S.A.
Journal of Theoretical Biology (Impact Factor: 2.12). 05/2001; 209(3):333-344. DOI: 10.1006/jtbi.2001.2269
Source: PubMed

ABSTRACT

We present a mathematical framework that combines extinction–colonization dynamics with the dynamics of patch succession. We draw an analogy between the epidemiological categorization of individuals (infected, susceptible, latent and resistant) and the patch structure of a spatially heterogeneous landscape (occupied–suitable, empty–suitable, occupied–unsuitable and empty–unsuitable). This approach allows one to consider life-history attributes that influence persistence in patchy environments (e.g., longevity, colonization ability) in concert with extrinsic processes (e.g., disturbances, succession) that lead to spatial heterogeneity in patch suitability. It also allows the incorporation of seed banks and other dormant life forms, thus broadening patch occupancy dynamics to include sink habitats. We use the model to investigate how equilibrium patch occupancy is influenced by four critical parameters: colonization rate, extinction rate, disturbance frequency and the rate of habitat succession. This analysis leads to general predictions about how the temporal scaling of patch succession and extinction–colonization dynamics influences long-term persistence. We apply the model to herbaceous, early-successional species that inhabit open patches created by periodic disturbances. We predict the minimum disturbance frequency required for viable management of such species in the Florida scrub ecosystem.

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Available from: Hugh P Possingham, Mar 20, 2015
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    • "Successional dynamics are a well-documented consequence of disturbance (Bengtsson et al. 2000;Lake et al. 2007;Leavesley et al. 2010;Banks et al. 2011), with species commonly showing preference for early or late postdisturbance stages, or having habitat suitability mediated by disturbance return intervals. Therefore, disturbance history can have major effects on amount and connectivity of suitable habitat, as well as viability of populations (Amarasekare and Possingham 2001). Introducing simulation approaches that explicitly include habitat dynamics would further improve insights into dynamics of genetic diversity under variation in disturbance regimes. "
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    • "Empirical examples of such systems are agricultural landscapes in which habitable areas are frequently changed by mowing and harvesting, lands in which flood and inundation events are frequent, and early-successional communities in disturbed sites, where the habitat quality declines due to resource depletion and the timing for habitat to become suitable for recolonization depends on disturbance (Stelter et al. 1997; Amarasekare and Possingham 2001; Blaum et al. 2012). In all of these systems dispersal is closely linked to the state of the habitat patch, and longterm survival in such habitat systems depends on the timing of dispersal. "
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    • "Keymer et al., 2000; Amarasekare and Possingham, 2001; Wimberly , 2006), mostly focusing on a comparison between dynamical vs static systems. In general, these theoretical studies have shown that metapopulation occupancy of ephemeral habitats is lower than that of permanent habitats (Amarasekare and Possingham, 2001) and that habitat turnover rate is negatively correlated with patch occupancy (Keymer et al., 2000). An intuitive implication of these shifting mosaics is that, at some point, as habitat conditions worsen, individuals using a patch will need to relocate into other patches of suitable habitat. "
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