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1.
Environ Policy Gov ; 34(1): 65-76, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38516549

RESUMO

Effective governance of social-ecological systems (SES) is an enduring challenge, especially in coastal environments where accelerating impacts of climate change are increasing pressure on already stressed systems. While resilience is often proposed as a suitable framing to re-orient governance and management, the literature includes many different, and sometimes conflicting, definitions and ideas that influence how the concept is applied, especially in coastal environments. This study combines discourse analysis of the coastal governance literature and key informant interviews in Tasmania, Australia, demonstrating inconsistencies and confusion in the way that resilience is framed in coastal governance research and practice. We find that resilience is most often framed as (1) a rate of recovery from disturbance or (2) the process of acting in response to, or anticipation of, a disturbance. A third framing considers resilience as an emergent property of SESs. This framing, social-ecological resilience, accounts for multiple configurations of SES, which necessitates adaptation and transformation strategies to address changes across temporal and spatial scales. Coastal managers recognised the value of this third framing for governing coastal SESs, yet the confusion and inconsistency in the literature was also evident in how they understood and applied resilience in practice. Expanding the use of social-ecological resilience is essential for more effective coastal governance, given the dynamics of coastal SESs and the intensity of social, economic, and environmental drivers of change these systems face. However, this requires addressing the unclear, confused, and superficial use of resilience-oriented concepts in research and policy discourse.

2.
Adv Ecol Res ; 69: 69-81, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38152344

RESUMO

Panarchy is a heuristic of complex system change rooted in resilience science. The concept has been rapidly assimilated across scientific disciplines due to its potential to envision and address sustainability challenges, such as climate change and regime shifts, that pose significant challenges for humans in the Anthropocene. However, panarchy has been studied almost exclusively via qualitative research. Quantitative approaches are scarce and preliminary but have revealed novel insights that allow for a more nuanced understanding of the heuristic and resilience science more generally. In this roadmap we discuss the potential for future quantitative approaches to panarchy. Transdisciplinary development of quantitative approaches, combined with advances in data accrual, curation and machine learning, may build on current tools. Combined with qualitative research and traditional approaches used in ecology, quantification of panarchy may allow for broad inference of change in complex systems of people and nature and provide critical information for management of social-ecological systems.

3.
Glob Sustain ; 6(e8): 1-14, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37692862

RESUMO

Non-technical summary: The United Nations' sustainable development goals (SDGs) articulate societal aspirations for people and our planet. Many scientists have criticised the SDGs and some have suggested that a better understanding of the complex interactions between society and the environment should underpin the next global development agenda. We further this discussion through the theory of social-ecological resilience, which emphasises the ability of systems to absorb, adapt, and transform in the face of change. We determine the strengths of the current SDGs, which should form a basis for the next agenda, and identify key gaps that should be filled. Technical summary: The United Nations' sustainable development goals (SDGs) are past their halfway point and the next global development agenda will soon need to be developed. While laudable, the SDGs have received strong criticism from many, and scholars have proposed that adopting complex adaptive or social-ecological system approaches would increase the effectiveness of the agenda. Here we dive deeper into these discussions to explore how the theory of social-ecological resilience could serve as a strong foundation for the next global sustainable development agenda. We identify the strengths and weaknesses of the current SDGs by determining which of the 169 targets address each of 43 factors affecting social-ecological resilience that we have compiled from the literature. The SDGs with the strongest connections to social-ecological resilience are the environment-focus goals (SDGs 2, 6, 13, 14, 15), which are also the goals consistently under-prioritised in the implementation of the current agenda. In terms of the 43 factors affecting social-ecological resilience, the SDG strengths lie in their communication, inclusive decision making, financial support, regulatory incentives, economic diversity, and transparency in governance and law. On the contrary, ecological factors of resilience are seriously lacking in the SDGs, particularly with regards to scale, cross-scale interactions, and non-stationarity. Social media summary: The post-2030 agenda should build on strengths of SDGs 2, 6, 13, 14, 15, and fill gaps in scale, variability, and feedbacks.

4.
PLoS One ; 18(8): e0289706, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37556438

RESUMO

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.


Assuntos
Ecossistema , Áreas Alagadas , Animais , Nebraska , Rios , Conservação dos Recursos Naturais , Mamíferos
5.
Sustain Sci ; : 1-16, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-37363302

RESUMO

Coping with surprise and uncertainty resulting from the emergence of undesired and unexpected novelty or the sudden reorganization of systems at multiple spatiotemporal scales requires both a scientific process that can incorporate diverse expertise and viewpoints, and a scientific framework that can account for the structure and dynamics of interacting social-ecological systems (SES) and the inherent uncertainty of what might emerge in the future. We argue that combining a convergence scientific process with a panarchy framework provides a pathway for improving our understanding of, and response to, emergence. Emergent phenomena are often unexpected (e.g., pandemics, regime shifts) and can be highly disruptive, so can pose a significant challenge to the development of sustainable and resilient SES. Convergence science is a new approach promoted by the U.S. National Science Foundation for tackling complex problems confronting humanity through the integration of multiple perspectives, expertise, methods, tools, and analytical approaches. Panarchy theory is a framework useful for studying emergence, because it characterizes complex systems of people and nature as dynamically organized and structured within and across scales of space and time. It accounts for the fundamental tenets of complex systems and explicitly grapples with emergence, including the emergence of novelty, and the emergent property of social-ecological resilience. We provide an overview of panarchy, convergence science, and emergence. We discuss the significant data and methodological challenges of using panarchy in a convergence approach to address emergent phenomena, as well as state-of-the-art methods for overcoming them. We present two examples that would benefit from such an approach: climate change and its impacts on social-ecological systems, and the relationships between infectious disease and social-ecological systems.

6.
PLoS One ; 18(6): e0286621, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37267398

RESUMO

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.


Assuntos
Quirópteros , Ecossistema , Animais , Humanos , Árvores , Insetos , Comportamento Alimentar
7.
Ecol Appl ; 33(2): e2761, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36218183

RESUMO

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.


Assuntos
Ecossistema , Traqueófitas , Animais , Filogenia , Insetos , Plantas , Espécies Introduzidas
8.
Sustain Sci ; 19: 325-346, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38362047

RESUMO

Natural resource governance in the face of climate change represents one of the seminal challenges of the Anthropocene. A number of innovative approaches have been developed in, among others, the fields of ecology, governance, and sustainability sciences for managing uncertainty and scarcity through a coordinated approach to natural resource governance. However, the absence of an enabling legal and regulatory framework has been identified in the literature as one of the primary barriers constraining the formal operationalization of these governance approaches. In this paper, we show how these approaches provide tools for analyzing procedural mandates across governmental levels and sectors in the natural resource governance space. We also find that there has been inadequate consideration of the potential in existing laws and regulations for cross-sectoral and multi-level coordination of natural resource governance. On this basis, we develop and apply a protocol that draws on the traditional legal method of doctrinal analysis to demonstrate how to identify existing, untapped legal capacity to promote coordinated governance of natural resources through an in-depth case study of water resources in South Africa. We then show how these untapped capacities within existing legal structures may be operationalized to improve natural resource governance. Further, this protocol is portable to other countries, provinces (states), and localities around the world.

9.
Bioscience ; 73(11): 800-807, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-38516522

RESUMO

Adaptive management is a powerful approach to management of social-ecological systems in circumstances with high uncertainty and high controllability. Cross-scale interactions increase uncertainty while managing. When undertaking adaptive management, although largely overlooked, it is important to account for spatial and temporal scales to mediate within- and cross-scale effects of management actions. This is particularly true when managing for multiple social and ecological goals. The iterative nature of an adaptive approach has the capacity to accommodate tradeoffs among different stakeholder priorities and multiple ecosystem attributes within and across scales. In this paper, we introduce multi-scale adaptive management of social-ecological systems and demonstrate the importance of this approach with case studies of the Great Plains of North America and the Platte River Basin in the United States. Adaptive management combined with a focus on scale and cross-scale interactions using the panarchy model of social-ecological systems can help to improve management outcomes.

10.
Int J Health Policy Manag ; 11(9): 1949-1952, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35247939

RESUMO

Adaptive capacity is a critical component of building resilience in healthcare (RiH). Adaptive capacity comprises the ability of a system to cope with and adapt to disturbances. However, "shocks," such as the current coronavirus disease 2019 (COVID-19) pandemic, can potentially exceed critical adaptation thresholds and lead to systemic collapse. To effectively manage healthcare systems during periods of crises, both adaptive and transformative changes are necessary. This commentary discusses adaptation and transformation as two complementary, integral components of resilience and applies them to healthcare. We treat resilience as an emergent property of complex systems that accounts for multiple, often disparately distinct regimes in which multiple processes (eg, adaptation, recovery) are subsumed and operate. We argue that Convergence Mental Health and other transdisciplinary paradigms such as Brain Capital and One Health can facilitate resilience planning and management in healthcare systems.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , New South Wales , Ontário , Atenção à Saúde , Austrália , Governo
11.
Glob Sustain ; 5: 1-9, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37383242

RESUMO

Non-technical summary: Our analysis shows that the framing of social vulnerability is shaped by a narrow definition of resilience, focusing on post-disaster return and recovery responses. This perspective does not account for the dynamism and non-stationarity of social-ecological systems (SES) which is becoming increasingly important in the face of accelerating environmental change. Incorporating social-ecological resilience into social vulnerability analysis can improve coastal governance by accounting for adaptation and transformation, as well as scale and cross-scale interactions. Technical summary: Social vulnerability analysis has been unable to deliver outcomes that reflect the reality of vulnerability and its consequences in an era characterised by accelerating environmental change. In this work, we used critical discourse analysis and key informant interviews to understand different framings of social vulnerability in coastal governance and management, globally and in New Zealand. We found that the framing of system vulnerability could vary depending on the definition of resilience adopted, which has critical ramifications for coastal governance of linked systems of humans and nature. We found that the framing of social vulnerability in coastal governance is mainly influenced by engineering, community and disaster resilience, focusing on return and recovery governance responses to environmental change (e.g. hurricanes, wildfires). Instead, we suggest a novel perspective based on social-ecological resilience, which more accurately reflects the dynamics of linked systems of humans and nature (SES). This revised perspective, general vulnerability, accounts for the dynamics of Earth's systems across various spatial and temporal scales in the face of accelerating environmental change. Accounting for social-ecological resilience and its core aspects (i.e. panarchy, adaptation and transformation) is essential for informing coastal governance of SES (Do we adapt? or Do we transform the SES?). Social media summary: Social-ecological resilience is essential for social vulnerability analysis in the face of accelerating environmental change.

12.
Ecol Soc ; 26(4): 1-7, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34804170

RESUMO

A key challenge of the Anthropocene is to confront the dynamic complexity of systems of people and nature to guide robust interventions and adaptations across spatiotemporal scales. Panarchy, a concept rooted in resilience theory, accounts for this complexity, having at its core multiscale organization, interconnectedness of scales, and dynamic system structure at each scale. Despite the increasing use of panarchy in sustainability research, quantitative tests of its premises are scarce, particularly as they pertain to management consequences in ecosystems. In this study we compared the physicochemical environment of managed (limed) and minimally disturbed reference lakes and used time series modeling and correlation analyses to test the premises of panarchy theory: (1) that both lake types show dynamic structure at multiple temporal scales, (2) that this structure differs between lake types due to liming interacting with the natural disturbance regime of lakes, and (3) that liming manifests across temporal scales due to cross-scale connectivity. Hypotheses 1 and 3 were verified whereas support for hypothesis 2 was ambiguous. The literature suggests that liming is a "command-and-control" management form that fails to foster self-organization manifested in lakes returning to pre-liming conditions once management is ceased. In this context, our results suggest that redundance of liming footprints across scales, a feature contributing to resilience, in the physicochemical environment alone may not be enough to create a self-organizing limed lake regime. Further research studying the broader biophysical lake environment, including ecological communities of pelagic and benthic habitats, will contribute to a better understanding of managed lake panarchies. Such insight may further our knowledge of ecosystem management in general and of limed lakes in particular.

13.
J Environ Manage ; 291: 112550, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33965707

RESUMO

A key pursuit in contemporary ecology is to differentiate regime shifts that are truly irreversible from those that are hysteretic. Many ecological regime shifts have been labeled as irreversible without exploring the full range of variability in stabilizing feedbacks that have the potential to drive an ecological regime shift back towards a desirable ecological regime. Removing fire from grasslands can drive a regime shift to juniper woodlands that cannot be reversed using typical fire frequency and intensity thresholds, and has thus been considered irreversible. This study uses a unique, long-term experimental fire landscape co-dominated by grassland and closed-canopy juniper woodland to determine whether extreme fire can shift a juniper woodland regime back to grassland dominance using aboveground herbaceous biomass as an indicator of regime identity. We use a space-for-time substitute to quantify herbaceous biomass following extreme fire in juniper woodland up to 15 years post-fire and compare these with (i) 15 years of adjacent grassland recovery post-fire, (ii) unburned closed-canopy juniper woodland reference sites and (iii) unburned grassland reference sites. Our results show grassland dominance rapidly emerges following fires that operate above typical fire intensity thresholds, indicating that grassland-juniper woodlands regimes are hysteretic rather than irreversible. One year following fire, total herbaceous biomass in burned juniper stands was comparable to grasslands sites, having increased from 5 ± 3 g m-2 to 142 ± 42 g m-2 (+2785 ± 812 percent). Herbaceous dominance in juniper stands continued to persist 15-years after initial treatment, reaching a maximum of 337 ± 42 g m-2 eight years post-fire. In juniper encroached grasslands, fires that operate above typical fire intensity thresholds can provide an effective method to reverse juniper woodland regime shifts. This has major implications for regions where juniper encroachment threatens rancher-based economies and grassland biodiversity and provides an example of how to operationalize resilience theory to disentangle irreversible thresholds from hysteretic system behavior.


Assuntos
Ecossistema , Incêndios , Biodiversidade , Biomassa , Florestas , Pradaria
14.
Ecol Soc ; 26(4): 1-9, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35116065

RESUMO

Managing social-ecological systems toward desirable regimes requires learning about the system being managed while preparing for many possible futures. Adaptive management (AM) and scenario planning (SP) are two systems management approaches that separately use learning to reduce uncertainties and employ planning to manage irreducible uncertainties, respectively. However, each of these approaches have limitations that confound management of social-ecological systems. Here, we introduce iterative scenarios (IS), a systems management approach that is a hybrid of the scopes and relationships to uncertainty and controllability of AM and SP that combines the "iterativeness" of AM and futures planning of SP. Iterative scenarios is appropriate for situations with high uncertainty about whether a management action will lead to intended outcomes, the desired benefits are numerous and cross-scale, and it is difficult to account for the social implications around the natural resource management options. The value of iterative scenarios is demonstrated by applying the approach to green infrastructure futures for a neighborhood in the city of Cleveland, Ohio, U.S., that had experienced long-term, systemic disinvestment. The Cleveland green infrastructure project was particularly well suited to the IS approach given that learning about environmental factors was necessary and achievable, but what would be socially desirable and possible was unknown. However, iterative scenarios is appropriate for many social-ecological systems where uncertainty is high as IS accommodates real-world complexity faced by management.

15.
Ecol Soc ; 25(1): 1-4, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32523609

RESUMO

Management frequently creates system conditions that poorly mimic the conditions of a desirable self-organizing regime. Such management is ubiquitous across complex systems of people and nature and will likely intensify as these systems face rapid change. However, it is highly uncertain whether the costs (unintended consequences, including negative side effects) of management but also social dynamics can eventually outweigh benefits in the long term. We introduce the term "coerced regime" to conceptualize this management form and tie it into resilience theory. The concept encompasses proactive and reactive management to maintain desirable and mitigate undesirable regime conditions, respectively. A coerced regime can be quantified through a measure of the amount of management required to artificially maintain its desirable conditions. Coerced regimes comprise "ghosts" of self-sustaining desirable system regimes but ultimately become "dead regimes walking" when these regimes collapse as soon as management is discontinued. We demonstrate the broad application of coerced regimes using distinct complex systems of humans and nature (human subjects, aquatic and terrestrial environments, agriculture, and global climate). We discuss commonalities and differences between these examples to identify tradeoffs between benefits and harms of management. The concept of coerced regimes can spur thinking and inform management about the duality of what we know and can envision versus what we do not know and therefore cannot envision-a pervasive sustainability conundrum as planet Earth swiftly moves towards a future without historical analogue.

16.
Front Ecol Environ ; 18(10): 576-583, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33408590

RESUMO

Addressing unexpected events and uncertainty represents one of the grand challenges of the Anthropocene, yet ecosystem management is constrained by existing policy and laws that were not formulated to deal with today's accelerating rates of environmental change. In many cases, managing for simple regulatory standards has resulted in adverse outcomes, necessitating innovative approaches for dealing with complex social-ecological problems. We highlight a project in the US Great Plains where panarchy - a conceptual framework that emerged from resilience - was implemented at project onset to address the continued inability to halt large-scale transition from grass-to-tree dominance in central North America. We review how panarchy was applied, the initial outcomes and evidence for policy reform, and the opportunities and challenges for which it could serve as a useful model to contrast with traditional ecosystem management approaches.

17.
Ecol Evol ; 9(21): 12216-12230, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31832155

RESUMO

A long-standing goal of invasion biology is to identify factors driving highly variable impacts of non-native species. Although hypotheses exist that emphasize the role of evolutionary history (e.g., enemy release hypothesis & defense-free space hypothesis), predicting the impact of non-native herbivorous insects has eluded scientists for over a century.Using a census of all 58 non-native conifer-specialist insects in North America, we quantified the contribution of over 25 factors that could affect the impact they have on their novel hosts, including insect traits (fecundity, voltinism, native range, etc.), host traits (shade tolerance, growth rate, wood density, etc.), and evolutionary relationships (between native and novel hosts and insects).We discovered that divergence times between native and novel hosts, the shade and drought tolerance of the novel host, and the presence of a coevolved congener on a shared host, were more predictive of impact than the traits of the invading insect. These factors built upon each other to strengthen our ability to predict the risk of a non-native insect becoming invasive. This research is the first to empirically support historically assumed hypotheses about the importance of evolutionary history as a major driver of impact of non-native herbivorous insects.Our novel, integrated model predicts whether a non-native insect not yet present in North America will have a one in 6.5 to a one in 2,858 chance of causing widespread mortality of a conifer species if established (R 2 = 0.91) Synthesis and applications. With this advancement, the risk to other conifer host species and regions can be assessed, and regulatory and pest management efforts can be more efficiently prioritized.

18.
Proc Natl Acad Sci U S A ; 116(40): 19899-19904, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527247

RESUMO

Over the past several decades, environmental governance has made substantial progress in addressing environmental change, but emerging environmental problems require new innovations in law, policy, and governance. While expansive legal reform is unlikely to occur soon, there is untapped potential in existing laws to address environmental change, both by leveraging adaptive and transformative capacities within the law itself to enhance social-ecological resilience and by using those laws to allow social-ecological systems to adapt and transform. Legal and policy research to date has largely overlooked this potential, even though it offers a more expedient approach to addressing environmental change than waiting for full-scale environmental law reform. We highlight examples from the United States and the European Union of untapped capacity in existing laws for fostering resilience in social-ecological systems. We show that governments and other governance agents can make substantial advances in addressing environmental change in the short term-without major legal reform-by exploiting those untapped capacities, and we offer principles and strategies to guide such initiatives.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Política Ambiental , Biodiversidade , Ecologia , União Europeia , Governo , Meio Social , Estados Unidos
19.
J Environ Manage ; 240: 368-373, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30953990

RESUMO

Mechanisms underlying the loss of ecological resilience and a shift to an alternate regime with lower ecosystem service provisioning continues to be a leading debate in ecology, particularly in cases where evidence points to human actions and decision-making as the primary drivers of resilience loss and regime change. In this paper, we introduce the concept of coerced resilience as a way to explore the interplay among social power, ecological resilience, and fire management, and to better understand the unintended and undesired regime changes that often surprise ecosystem managers and governing officials. Philosophically, coercion is the opposite of freedom, and uses influence or force to gain compliance among local actors. The coercive force imposed by societal laws and policies can either enhance or reduce the potential to manage for essential structures and functions of ecological systems and, therefore, can greatly alter resilience. Using a classical fire-dependent regime shift from North America (tallgrass prairie to juniper woodland), and given that coercion is widespread in fire management today, we quantify relative differences in resilience that emerge in a policy-coerced fire system compared to a theoretical, policy-free fire system. Social coercion caused large departures in the fire conditions associated with alternative grassland and juniper woodland states, and the potential for a grassland state to emerge to dominance became increasingly untenable with fire as juniper cover increased. In contrast, both a treeless, grassland regime and a co-dominated grass-tree regime emerged across a wide range of fire conditions in the absence of policy controls. The severe coercive forcing present in fire management in the Great Plains, and corresponding erosion of grassland resilience, points to the need for transformative environmental governance and the rethinking of social power structures in modern fire policies.


Assuntos
Ecossistema , Incêndios , Ecologia , Florestas , Humanos , América do Norte
20.
Ecol Evol ; 9(4): 1869-1879, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30847078

RESUMO

Disturbance legacies structure communities and ecological memory, but due to increasing changes in disturbance regimes, it is becoming more difficult to characterize disturbance legacies or determine how long they persist. We sought to quantify the characteristics and persistence of material legacies (e.g., biotic residuals of disturbance) that arise from variation in fire severity in an eastern ponderosa pine forest in North America. We compared forest stand structure and understory woody plant and bird community composition and species richness across unburned, low-, moderate-, and high-severity burn patches in a 27-year-old mixed-severity wildfire that had received minimal post-fire management. We identified distinct tree densities (high: 14.3 ± 7.4 trees per ha, moderate: 22.3 ± 12.6, low: 135.3 ± 57.1, unburned: 907.9 ± 246.2) and coarse woody debris cover (high: 8.5 ± 1.6% cover per 30 m transect, moderate: 4.3 ± 0.7, low: 2.3 ± 0.6, unburned: 1.0 ± 0.4) among burn severities. Understory woody plant communities differed between high-severity patches, moderate- and low-severity patches, and unburned patches (all p < 0.05). Bird communities differed between high- and moderate-severity patches, low-severity patches, and unburned patches (all p < 0.05). Bird species richness varied across burn severities: low-severity patches had the highest (5.29 ± 1.44) and high-severity patches had the lowest (2.87 ± 0.72). Understory woody plant richness was highest in unburned (5.93 ± 1.10) and high-severity (5.07 ± 1.17) patches, and it was lower in moderate- (3.43 ± 1.17) and low-severity (3.43 ± 1.06) patches. We show material fire legacies persisted decades after the mixed-severity wildfire in eastern ponderosa forest, fostering distinct structures, communities, and species in burned versus unburned patches and across fire severities. At a patch scale, eastern and western ponderosa system responses to mixed-severity fires were consistent.

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