Adaptive capacity can present challenges for modelling as it encompasses multiple ecological and evolutionary processes such as natural selection, genetic drift, gene flow and phenotypic plasticity. Spatially explicit, individual‐based models provide an outlet for simulating these complex interacting eco‐evolutionary processes. We expanded the existing Cost‐Distance Meta‐POPulation (CDMetaPOP) framework with inducible plasticity modelled as a habitat selection behaviour, using temperature or habitat quality variables, with a genetically based selection threshold conditioned on past individual experience. To demonstrate expected results in the new module, we simulated hypothetical populations and then evaluated model performance in populations of redband trout (
Rivers are dynamic, complex integrators of their environment, which makes verification of the beneficial outcomes of restoration challenging. Thermal regime is central to habitat suitability and is often a focus in planning and evaluating the impact of restoration and climate resilience. Among these concerns, high summer stream temperature has frequently been identified as a limiting factor for salmon, steelhead, and trout. Our objective was to demonstrate the utility of combining high resolution thermal observation and modelling to evaluate restoration designed to mitigate stream thermal processes. This was demonstrated on the Middle Fork of the John Day River which is a critically impacted salmonid fishery in northeast Oregon, USA. We employed distributed temperature sensing and energy‐balance modelling to define the thermal regime. Restoration was predicted to result in a 0.7°C reduction of peak daily stream temperatures while increasing night temperatures by 0.9°C. This combined modelling and monitoring approach suggests that the 2012 restoration offered relief for native fish species stressed by excessive stream temperatures. This powerful combination of technology can be used in many projects to make optimal use of restoration investments to achieve durable and quantifiable improvements in habitat.
more » « less- Award ID(s):
- 1832170
- NSF-PAR ID:
- 10455510
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- River Research and Applications
- Volume:
- 36
- Issue:
- 8
- ISSN:
- 1535-1459
- Page Range / eLocation ID:
- p. 1430-1441
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Microbial community composition varies across stream habitats. However, there is little understanding of how varying hydraulic and geomorphic factors influence microbial distribution along a succession of pools. This study examines how substrate, geomorphological and hydraulic habitat variables may drive bacterial community composition within different stream pool habitats of a temperate headwater stream. Microbial community structures from rock biofilm and sediment samples within each of the 10 selected stream pools of White Clay Creek, PA, were determined by high‐throughput sequencing of 16S rRNA genes. The grain size distribution, organic matter content, streamflow velocity, temperature regime and morphology of each pool were quantified to characterize the pool habitats' variability. Multivariate statistical analysis revealed significant differences in the microbial community composition linked to the substrate's stability within the pool units. Indeed, soft and more mobile sediments were dominated by heterotrophic bacteria, while photosynthetic microorganisms (e.g., microalgae and cyanobacteria) were mainly found on rock biofilm. The difference in the distribution of bacterial communities can be explained by variations in the local hydraulic (i.e., depth and velocity) and the thermal conditions (daily fluctuation, min and max). These results highlight the geomorphological and hydrologic drivers for small‐scale diversity in bacterial communities and provide a better understanding of how maintaining and promoting variability in streambed physical properties may enhance microbial diversity. Better integration of these drivers into stream restoration practices will allow the inclusion of microorganisms, the trophic levels that are usually overlooked but still play critical roles in stream ecology.
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