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Abstract Adaptive management is an approach for stewardship of social–ecological systems in circumstances with high uncertainty and high controllability. Although they are largely overlooked in adaptive management (and social–ecological system management), it is important to account for spatial and temporal scales to mediate within- and cross-scale effects of management actions, because cross-scale interactions increase uncertainty and can lead to undesirable consequences. The iterative nature of an adaptive approach can be expanded to multiple scales to accommodate different stakeholder priorities and multiple ecosystem attributes. In this Forum, we introduce multiscale adaptive management of social–ecological systems, which merges adaptive management with panarchy (a multiscale model of social–ecological systems) and demonstrate the importance of this approach with case studies from the Great Plains of North America and the Platte River Basin, in the United States. Adaptive management combined with a focus on the panarchy model of social–ecological systems can help to improve the management of social–ecological systems.
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Charting the course of Sargassum : Incorporating nonlinear elastic interactions and life cycles in the Maxey–Riley model
Abstract The surge of pelagic Sargassum in the Intra-America Seas, particularly the Caribbean Sea, since the early 2010s has raised significant ecological concerns. This study emphasizes the need for a mechanistic understanding of Sargassum dynamics to elucidate the ecological impacts and uncertainties associated with blooms. By introducing a novel transport model, physical components such as ocean currents and winds are integrated with biological aspects affecting the Sargassum life cycle, including reproduction, grounded in an enhanced Maxey–Riley theory for floating particles. Nonlinear elastic forces among the particles are included to simulate interactions within and among Sargassum rafts. This promotes aggregation, consistent with observations, within oceanic eddies, which facilitate their transport. This cannot be achieved by the so-called leeway approach to transport, which forms the basis of current Sargassum modeling. Using satellite-derived data, the model is validated, outperforming the leeway model. Publicly accessible codes are provided to support further research and ecosystem management efforts. This comprehensive approach is expected to improve predictive capabilities and management strategies regarding Sargassum dynamics in affected regions, thus contributing to a deeper understanding of marine ecosystem dynamics and resilience.
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- Award ID(s):
- 2148499
- PAR ID:
- 10549915
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- PNAS Nexus
- Volume:
- 3
- Issue:
- 10
- ISSN:
- 2752-6542
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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