Duration and temporal stability of resource subsidy largely affect the response of recipient communities. Factors that influence the temporal dynamics of resource subsidy from aquatic‐to‐terrestrial habitats by emerging aquatic insects were examined in this study. By measuring the flux of aquatic insect emergence from six habitats in a river over summer, we found that the timing of emergence varied by habitats for each dominant taxa, and that different species emerged at different times of the summer sequentially. We found that spatial variation in the emergence timing caused by the spatial heterogeneity of the water temperature, and so on in the source habitat can temporally stabilize the subsidy of each species from the whole river. Similarly, we found that the variation in emergence timing between species contributed to the temporal stability of subsidies from each habitat. The contribution of spatial heterogeneity to the temporal stability varied by the focal species and the contribution of species diversity varied by habitats. This study demonstrates how the ecological function of spatial heterogeneity and species diversity crosses the boundary of ecosystems by temporally stabilizing resource subsidies.
The movement of organisms across habitat boundaries has important consequences for populations, communities, and ecosystems. However, because most species are not well adapted to all habitat types, dispersal into suboptimal habitats could induce physiological changes associated with persistence strategies that influence community assembly. For example, high rates of cross‐boundary dispersal are thought to maintain sink populations of terrestrial bacteria in aquatic habitats, but these bacteria may also persist by lowering their metabolic activity, introducing metabolic heterogeneity that buffers the population against species sorting. To differentiate between these assembly processes, we analyzed bacterial composition along a hydrological flow path from terrestrial soils through an aquatic reservoir by sequencing the active and total (active + inactive) portions of the community. When metabolic heterogeneity was ignored, our data were consistent with views that cross‐boundary dispersal is important for structuring aquatic bacterial communities. In contrast, we found evidence for strong species sorting in the active portion of the aquatic community, suggesting that dispersal may have a weaker effect than persistence strategies on aquatic community assembly. By accounting for metabolic heterogeneity in complex communities, our findings clarify the roles of local‐ and regional‐scale assembly processes in terrestrial‐aquatic meta‐ecosystems.
more » « less- PAR ID:
- 10456289
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology
- Volume:
- 101
- Issue:
- 4
- ISSN:
- 0012-9658
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Time Period 2016.
Major Taxa Studied Bacteria inhabiting
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