Metapopulation

Griesemer, J. R. and Wade, M. J. (2000), Populational heritability extending punnett square concepts to evolution at the metapopulation level , Biology and Philosophy, 15, 1 - 17. 

Claessen, D.C., Gilligan, A. and van den Bosch, F. (2005). Which traits promote persistence of feral GM crops Part 2 implications of metapopulation structure , Oikos, 110, 30 12. 

Wiens, J.A. 1997. Metapopulation dynamics and landscape ecology. In Metapopulation Biology (I. Hanski and M.E. Gilpin, eds), pp. 43-62. Academic Press, San Diego. 

Saikkonen K et al.. The persistence of vertically transmitted fungi in grass metapopulations, Proc Roy Soc LondB Biol Sci 269 1397—1403, 2002. 

A recently developed metapopulation model to extrapolate responses of aquatic invertebrates as observed in mesocosms to assess their recovery potential in the field is provided by Van den Brink et al. (2007). When the primary interest is in the recovery of processes and functional groups, food-web models are the required mathematical tools (for an example, see Traas et al. 2004). Two drawbacks of these models are that they require detailed information on the species and functional groups of concern and that they are very specific to the species and functional groups and sites for which they are developed. 

Spromberg et al. (1998) used a toxicant-treated metapopulation model to explore the range of possible dynamics of populations in contaminated field sites. A singlespecies metapopulation model was developed, and the distribution of the chemical was assumed to be limited to one patch and contagious within that patch. Both persistent and degradable toxicants were modeled. Five principal conclusions resulted from the simulation studies ... 

Recently, metapopulation models have been successfully applied to assess the risks of contaminants to aquatic populations. A metapopulation model to extrapolate responses of the aquatic isopod Asellus aquaticus as observed in insecticide-stressed mesocosms to assess its recovery potential in drainage ditches, streams, and ponds is provided by van den Brink et al. (2007). They estimated realistic pyrethroid concentrations in these different types of aquatic ecosystems by means of exposure models used in the European legislation procedure for pesticides. It appeared that the rate of recovery of Asellus in pyrethroid-stressed drainage ditches was faster in the field than in the isolated mesocosms. However, the rate of recovery in drainage ditches was calculated to be lower than that in streams and ponds (van den Brink et al. 2007). In another study, the effects of flounder foraging behavior and habitat preferences on exposure to polychlorinated biphenyls in sediments were assessed by Linkov et al. (2002) using a tractable individual-based metapopulation model. In this study, the use of a spatially and temporally explicit model reduced the estimate of risk by an order of magnitude as compared with a nonspatial model (Linkov et al. 2002). 

To date, metapopulation models and spatially explicit models have been used predominantly to assess risks of contaminants and habitat quality on terrestrial wildlife species. There is, however, no reason to believe that these models, when adapted, cannot be used to assess ecological risks for aquatic populations. Output of these models is valuable, but further testing and uncertainty analyses are needed. 

Detection of differences in metapopulation responses in impacted landscapes Population dynamics... 

Prediction of responses Community to ecosystem Food-web models, metapopulation 4.5.4... 

Complex models (life stage, IBM, and energetic models) Food-web models, metapopulation models Food-web models... 

Highly specific 2 Extrapolation by statistical model Detection of differences in metapopulation responses in impacted landscapes Toxicity as part of multiple stress GIS modeling... 

Specific approach (not 0, 1, 2, 3, or 4) Detection of differences in metapopulation responses in Ecological indicators Monitoring... 

What is the spatial distribution of the exposed species with regard to both home ranges (as compared to the exposure sites) as well as the presence of refugia (in the case of a metapopulation structure of the exposed species) ... 

Akcakaya HR, Regan HM. 2002. Population models metapopulations. In Pastorok RA, Bar-tell SM, Ferson S, Ginzburg LR, editors. Ecological modeling in risk assessment chemical effects on populations, ecosystems, and landscapes. Boca Raton (FL) Lewis Publishers, p 83-96. 

Hanski I, Gyllenberg M. 1993. Two general metapopulation models and the core-satellite species hypothesis. Am Nat 132 360-382. 

Sherratt TN, Jepson PC. 1993. A metapopulation approach to modeling the long-term impact of pesticides on invertebrates. J Appl Ecol 30 696-705. 

Spromberg JA, John BM, Landis WG. 1998. Metapopulation dynamics indirect effects and multiple distinct outcomes in ecological risk assessment. Environ Toxicol Chem 17 1640-1649. 

Coupled with the necessity of making the replicates similar is the elimination of a key ingredient of naturally synthesized ecological structures the spatial and temporal heterogeneity. Spatial and temporal heterogeneity are one key to species richness, as in "The Paradox of the Plankton" (Hutchinson 1961). Environmental heterogeneity is key to the establishment of metapopulations, a key factor in the persistence of species. 

The next sections discuss the potential effects of toxicants upon populations that vary in distribution in a landscape. The first part describes the types of spatial structure, and the next section discusses the use of metapopulation models in examining the potential dynamics due to toxicants. 

Classic metapopulations result from low to intermediate migration between habitat patches. Not all potential habitats necessarily contain populations. Migration between patches affects the dynamics of local populations, even including recolonization following extinction. If sufficient dispersal between patches exists, then a "rescue effect" can prevent local extinctions. Persistence of a metapopulation requires migration rates between patches, which are sufficient enough to offset local extinction rates. 

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