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  1. 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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    Free, publicly-accessible full text available November 3, 2024
  2. Boundary organizations have a crucial function in environmental governance by facilitating the processes through which scientists and decision-makers generate, exchange, evaluate, and utilize knowledge to identify societal problems, propose potential solutions, and make decisions on appropriate courses of action. This support for evidence-informed decision making is essential in addressing environmental challenges effectively. Despite the growing popularity of boundary organizations, there remains a significant challenge in designing information dissemination platforms to bridge the communication divide between scientific experts and non-experts. To address this gap, we used natural language processing tools to analyze the communication strategies of a specific boundary organization – the Nebraska Water Center – and examined how these strategies evolved over time to address relevant water policy issues in the state. We identified three prominent topics in the Center’s periodicals between 1970 and 2018: policy and planning, water quality and quantity, and public engagement and workforce development. The prevalence of each topic changed over time, reflecting changes in both federal and state legislative priorities and subsequent responses from the scientific community. Our results also demonstrate how boundary organizations can design information exchange platforms that consider perspectives and needs of not only scientists and policymakers but also more diverse groups of actors. These findings are critical for developing strategies for bridging science and policy in environmental governance. 
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    Free, publicly-accessible full text available October 1, 2024
  3. Hewitt, Judi (Ed.)
    Species of different sizes interact with the landscape differently because ecological structure varies with scale, as do species movement capabilities and habitat requirements. As such, landscape connectivity is dependent upon the scale at which an animal interacts with its environment. Analyses of landscape connectivity must incorporate ecologically relevant scales to address scale-specific differences. Many evaluations of landscape connectivity utilize incrementally increasing buffer distances or other arbitrary spatial delineations as scales of analysis. Instead, we used a mammalian body mass discontinuity analysis to objectively identify scales in the Central Platte River Valley (CPRV) of Nebraska, U.S.A. We implemented a graph-theoretic network analysis to evaluate the connectivity of two wetland land cover types in the CPRV, wet meadow and emergent marsh, at multiple scales represented by groupings of species with similar body mass. Body mass is allometric with multiple traits of species, including dispersal distances. The landscape was highly connected at larger scales but relatively unconnected at smaller scales. We identified a threshold at which the landscape becomes highly connected between 500 m and 6,500 m dispersal distances. The presence of a connectivity threshold suggests that species with dispersal distances close to the threshold may be most vulnerable to habitat loss or reconfiguration and management should account for the connectivity threshold. Furthermore, we propose that a multiscale approach to management will be necessary to ensure landscape connectivity for diverse species. 
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    Free, publicly-accessible full text available August 9, 2024
  4. Becker, Daniel (Ed.)
    In agroecosystems, bats can provide a critical ecosystem service by consuming night-flying insect pests. However, many bats also face intense population pressures from human landscape modification, global change and novel diseases. To better understand the behavioral activity of different bat species with respect to space, time, habitat, and other bat species in this environment, we investigated species correlations in space and time over row crop agricultural fields. We used acoustic grids to document spatial and temporal co-occurrence or avoidance between bats and recorded eight species across the 10 field sites we sampled. All species significantly overlapped in two-dimensional space and displayed considerable temporal overlap during the night, yet often exhibited significantly different temporal activity patterns, suggesting fine scale partitioning behavior. Conversion of land to agriculture is likely to increase globally, making it critical to better understand how bat species interact with one another and the landscape to facilitate persistence in these human altered ecosystems. 
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  5. Science is increasingly a collaborative pursuit. Although the modern scientific enterprise owes much to individuals working at the core of their field, humanity is increasingly confronted by highly complex problems that require the integration of a variety of disciplinary and methodological expertise. In 2016, the U.S. National Science Foundation launched an initiative prioritizing support for convergence research as a means of “solving vexing research problems, in particular, complex problems focusing on societal needs.” We discuss our understanding of the objectives of convergence research and describe in detail the conditions and processes likely to generate successful convergence research. We use our recent experience as participants in a convergence workshop series focused on resilience in the Arctic to highlight key points. The emergence of resilience science over the past 50 years is presented as a successful contemporary example of the emergence of convergence. We close by describing some of the challenges to the development of convergence research, such as timescales and discounting the future, appropriate metrics of success, allocation issues, and funding agency requirements.

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  6. Abstract Roadsides can be vectors for tree invasion within rangelands by bisecting landscapes and facilitating propagule spread to interior habitat. Current invasive tree management in North America’s Great Plains focuses on reducing on-site (i.e., interior habitat) vulnerability through on-site prevention and eradication, but invasive tree management of surrounding areas known to serve as invasion vectors, such as roadsides and public rights-of-ways, is sporadic. We surveyed roadsides for invasive tree propagule sources in a central Great Plains grassland landscape to determine how much of the surrounding landscape is potentially vulnerable to roadside invasion, and by which species, and thereby provide insights into the locations and forms of future landcover change. Invasive tree species were widespread in roadsides. Given modest seed dispersal distances of 100–200 m, our results show that roadsides have potential to serve as major sources of rangeland exposure to tree invasion, compromising up to 44% of rangelands in the study area. Under these dispersal distances, funds spent removing trees on rangeland properties may have little impact on the landscape’s overall vulnerability, due to exposure driven by roadside propagule sources. A key implication from this study is that roadsides, while often neglected from management, represent an important component of integrated management strategies for reducing rangeland vulnerability to tree invasion. 
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  7. Garnas, Jeff R. (Ed.)
    Abstract Some introduced species cause severe damage, although the majority have little impact. Robust predictions of which species are most likely to cause substantial impacts could focus efforts to mitigate those impacts or prevent certain invasions entirely. Introduced herbivorous insects can reduce crop yield, fundamentally alter natural and managed forest ecosystems, and are unique among invasive species in that they require certain host plants to succeed. Recent studies have demonstrated that understanding the evolutionary history of introduced herbivores and their host plants can provide robust predictions of impact. Specifically, divergence times between hosts in the native and introduced ranges of a nonnative insect can be used to predict the potential impact of the insect should it establish in a novel ecosystem. However, divergence time estimates vary among published phylogenetic datasets, making it crucial to understand if and how the choice of phylogeny affects prediction of impact. Here, we tested the robustness of impact prediction to variation in host phylogeny by using insects that feed on conifers and predicting the likelihood of high impact using four different published phylogenies. Our analyses ranked 62 insects that are not established in North America and 47 North American conifer species according to overall risk and vulnerability, respectively. We found that results were robust to the choice of phylogeny. Although published vascular plant phylogenies continue to be refined, our analysis indicates that those differences are not substantial enough to alter the predictions of invader impact. Our results can assist in focusing biosecurity programs for conifer pests and can be more generally applied to nonnative insects and their potential hosts by prioritizing surveillance for those insects most likely to be damaging invaders. 
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