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Abstract Invasive alien species are one of the major threats to global biodiversity, ecosystem integrity, nature's contributions to people and human health. While scenarios about potential future developments have been available for other global change drivers for quite some time, we largely lack an understanding of how biological invasions might unfold in the future across spatial scales. Based on previous work on global invasion scenarios, we developed a workflow to downscale global scenarios to a regional and policy‐relevant context. We applied this workflow at the European scale to create four European scenarios of biological invasions until 2050 that consider different environmental, socio‐economic and socio‐cultural trajectories, namely the European Alien Species Narratives (Eur‐ASNs). We compared the Eur‐ASNs with their previously published global counterparts (Global‐ASNs), assessing changes in 26 scenario variables. This assessment showed a high consistency between global and European scenarios in the logic and assumptions of the scenario variables. However, several discrepancies in scenario variable trends were detected that could be attributed to scale differences. This suggests that the workflow is able to capture scale‐dependent differences across scenarios. We also compared the Global‐ and Eur‐ASNs with the widely used Global and European Shared Socioeconomic Pathways (SSPs), a set of scenarios developed in the context of climate change to capture different future socio‐economic trends. Our comparison showed considerable divergences in the scenario space occupied by the different scenarios, with overall larger differences between the ASNs and SSPs than across scales (global vs. European) within the scenario initiatives. Given the differences between the ASNs and SSPs, it seems that the SSPs do not adequately capture the scenario space relevant to understanding the complex future of biological invasions. This underlines the importance of developing independent but complementary scenarios focussed on biological invasions. The downscaling workflow we implemented and presented here provides a tool to develop such scenarios across different regions and contexts. This is a major step towards an improved understanding of all major drivers of global change, including biological invasions. Read the free Plain Language Summary for this article on the Journal blog.

Biosphere Futures (https://biospherefutures.net/) is a new online database to collect and discover scenario studies from across the world, with a specific focus on scenarios that explicitly incorporate interdependencies between humans and their supporting ecosystems. It provides access to a globally diverse collection of case studies that includes most ecosystems and regions, enabling exploration of the multifaceted ways in which the future might unfold. Together, the case studies illuminate the diversity and plurality of people’s expectations and aspirations for the future. The objective of Biosphere Futures is to promote the use of scenarios for sustainable development of the biosphere and to foster a community of practice around social-ecological scenarios. We do so by facilitating the assessment, synthesis, and comparative analysis of scenario case studies, pointing to relevant resources, and by helping practitioners and researchers to disseminate and showcase their own work. This article begins by outlining the rationale behind the creation of the database, followed by an introduction to its functionality and the criteria employed for selecting case studies. Subsequently, we present a synthesis of the first 100 case studies included in the scenarios database, highlighting emerging patterns and identifying potential avenues for further research. Finally, given that broader utilization and contributions to the database will enhance the achievement of Biosphere Futures’ objectives, we invite the creators of social-ecological scenarios to contribute additional case studies. By expanding the database’s breadth and depth, we can collectively foster a more nuanced understanding of the possible trajectories of our biosphere and enable better decision making for sustainable development.

Social-ecological interactions have been shown to generate interrelated and reoccurring sets of ecosystem services, also known as ecosystem service bundles. Given the potential utility of the bundles concept, along with the recent surge in interest it is timely to reflect on the concept, its current use and potential for the future. Based on our ecosystem service bundle experience, expertise, and ecosystem service bundle analyses, we have found critical elements for advancing the utility of ecosystem service bundle concept and deepening its impact in the future. In this paper we 1) examine the different conceptualizations of the ecosystem service bundle concept; 2) show the range of benefits of using a bundles approach; 3) explore key issues for improving research on ecosystem service bundles, including indicators, scale, and drivers and relationships between ecosystem services; and 4) outline priorities for the future by facilitating comparisons of ecosystem service bundle research.

Achieving global sustainability goals requires most people and societies to fundamentally revisit their relationship with nature. New approaches are called for to guide change processes towards sustainable futures that embrace the plurality of people’s desired relationships with nature. This paper presents a novel approach to exploring desirable futures for nature and people that was developed through an application in Nationaal Park Hollandse Duinen in the Netherlands. This new national park is developed bottom-up by a diverse group of actors reshaping their interactions with each other and with nature. Our approach, co-designed with key stakeholders of the national park, engages with a new pluralistic framework for human-nature relationships presented by the IPBES task force on scenarios and models to catalyze the development of nature-centered scenarios. We integrated this Nature Futures Framework with the Three Horizons Framework in a participatory workshop process designed to bring people’s diverse relationships with nature to the fore, and jointly envision desirable futures and the pathways to get there. We present a methodology to analyze and compare the visions and assess their potential contribution to the SDGs. We summarize the results of the application in Nationaal Park Hollandse Duinen and reflect on lessons learned. The approach successfully engaged participants in joint exploration of desirable futures for the national park based on their plural perspectives on human-nature relationships. We see much potential for its applications to support change processes in various social-ecological contexts toward more sustainable futures for nature and people.

Achieving sustainability in the Anthropocene requires radical changes to how human societies operate. The Seeds of Good Anthropocenes (SOGA) project has identified a diverse set of existing initiatives, called “seeds,” that have the potential to catalyze transformations toward more sustainable pathways. However, the empirical investigation of factors and conditions that enable successful sustainability transformations across multiple cases has been scarce. Building on a review of existing theoretical and empirical research, we developed a theoretical framework for assessing three features identified as important to transformative potential of innovative social-ecological initiatives: (1) learning practices, (2) empowerment, and (3) networking. We applied this framework to a set of African-led and Africa-related initiatives that we selected from the SOGA database that were divided into initiatives with more or less transformative potential. We coded the presence or absence of features relating to the theoretical framework using secondary data, and then compared the initiatives using qualitative comparative analysis (QCA). This analysis revealed that of the three features tested, Networking emerged as the most important feature for transformative potential when compared amongst cases. By developing and testing a framework for the comparison of cases we provide a basis for future comparative work to further identify and test properties of cases that enable transformation.

A key sustainability challenge in human-dominated landscapes is how to reconcile competing demands such as food production, water quality, climate regulation, and ecological amenities. Prior research has documented how efforts to prioritize desirable ecosystem services such as food and fiber have often led to tradeoffs with other services. However, the growing literature has revealed different and sometimes contradictory patterns in ecosystem service relationships. It thus remains unclear whether there are generalizable patterns across social-ecological systems, and if not, what factors explain the variations. In this study, we synthesize datasets of five ecosystem services from four social-ecological systems. We ask: (1) Are ecosystem service relationships consistent across distinct regional social-ecological systems? (2) How do ecosystem service relationships vary with land-use intensity at the landscape scale? (3) In case of ecosystem service tradeoffs, how does land-use intensity affect intersection points of tradeoffs along the landscape composition gradient? Our results reveal that land-use intensity increases magnitude of ecosystem service tradeoffs (e.g. food production vs. climate regulation and water quality) across landscapes. Land-use intensity also alters where provisioning and regulating services intersect: in high-intensity systems, food production and regulating services can be both sustained only at smaller proportions of agricultural lands, whereas in low-intensity systems, these services could be both supplied with greater proportions of agricultural lands. Our research demonstrates importance of considering multiple aspects of land uses (landscape composition and land-use intensity), and provides a more nuanced understanding and framework to enhance our ability to predict how land use alters ecosystem service relationships.

Burkina Faso and the wider Sahel region have experienced substantial changes in rainfall, population, and landscape use. These changes have altered ecosystem services, the benefits that people receive from ecosystems, and rural livelihoods. However, it is difficult to assess the magnitude of these changes because of missing and fragmented social, agricultural, and ecological data. We estimated changes in 10 key provisioning ecosystem services in rural Burkina Faso between 1952 and 2016. We used a simple model of plausible social-ecological changes to make a historical extrapolation that bridges these data gaps, and assessed historical changes. Our approach combined the interpretation of historic aerial photographs and satellite images, with field observations and interviews. We applied the approach for six villages in two administrative regions for six points in time. We modeled the use of historic ecosystems by analyzing a range of estimates of changes in the generation of each service and its value to people. We found that cultivated ecosystem services have increased 1.5–23 times over the study period, while the non-cultivated ecosystem services firewood, construction material, and medicine have decreased to 66–20% of their previous values. Per capita production of cultivated ecosystem services has remained relatively stable, while the per capita production of all other ecosystem services has decreased, to 54–11% of their 1952 values. Although alternatives are available for some ecosystem services, such as medicine and construction material, there are currently limited alternatives available for other services, such as firewood. Decline in wild food availability and consumption is likely to reduce the nutritional value of rural people’s food. Our analysis of changes demonstrates that shrubs and trees on fields generate many ecosystem services that are key to rural livelihoods, and that efforts to enhance crop yields should maintain shrubs and trees. Our approach for estimating historical ecosystem services may also be useful to apply in other data scarce regions.

How do social-ecological systems change over time? In 2002 C. S. Holling and colleagues proposed the concept of panarchy, which presented social-ecological systems as an interacting set of adaptive cycles, each produced by the dynamic tensions between novelty and efficiency at multiple scales. Initially introduced as a conceptual framework and set of metaphors, panarchy has gained the attention of scholars across many disciplines, and its ideas continue to inspire further conceptual developments. Almost 20 years after this concept was introduced, we reviewed how it has been used, tested, extended, and revised, through the combination of qualitative methods and machine learning. Document analysis was used to code panarchy features common to the scientific literature (N = 42), a qualitative analysis that was complemented with topic modeling of 2177 documents. We found that the adaptive cycle is the feature of panarchy that has attracted the most attention. Challenges remain in empirically grounding the metaphor, but recent theoretical and empirical work offer some avenues for future research.

Times of crisis offer a rare opportunity to understand the mechanisms underpinning the resilience of complex adaptive systems. The coronavirus pandemic that started in 2020 overwhelmed health systems worldwide and forced governments, businesses, and individuals to deploy a range of coping and adaptation strategies. Through an online survey targeting members of the Resilience Alliance and their collaborators, we examined 61 distinct strategies deployed in the initial months of the pandemic to assess empirically which resilience-building mechanisms were actually implemented to navigate the crisis. Our results show that managing connectivity, feedbacks, and learning were essential during the initial part of the pandemic. Other principles such as building diversity, redundancy, polycentricity, and inviting participation become important in rebuilding during the aftermath of a crisis, whereas keeping a systems view, monitoring slow variables, and practicing adaptive management are practices that should be incorporated during regular times.

In a complex and turbulent world, there is heightened interest in managing for resilience. However, resilience guides, particularly those used in the development field, often lack a theoretical grounding in complex adaptive systems. There is a demand for guidance on how to operationalize complexity in applications of resilience, such as resilience assessment and planning. This study synthesizes lessons from how twelve cases of social-ecological resilience practice are engaging with complexity. We assessed how each case engaged with complexity, according to a framework of six features of complex adaptive systems. The cases are situated in a diversity of contexts, that include rural villages in Tajikistan, a Swedish municipality, Australian catchment management authorities, a Canadian coastal fishery, and the Arctic council. Our results revealed two main ways of engaging with complexity: capturing and making sense of the complexity of a social-ecological system (system complexity) and embodying complexity into the participatory process (process complexity). Our comparison demonstrates that resilience practice provides a useful approach to address system complexity by, for example, conceptualizing social-ecological interactions, identifying interactions across scales, and assessing system dynamics. Strategies related to understanding the adaptive and emergent features of complex systems were less developed and widespread. The study also revealed a set of strategies to address process complexity, such as facilitating dialogue, building networks, and designing a flexible and iterative process, showing how complexity can be embedded into the resilience assessment process. The more participatory and embedded cases of resilience practice were stronger in these process-oriented strategies. The complexity framework we used and the identified practical strategies provide a theoretically-grounded resource for managers, decision-makers, and researchers on how to engage with complexity when applying resilience in a variety of contexts, including development and landscape management.

There are many calls to use the COVID 19 crisis as an opportunity for transforming to a future trajectory that is more equitable and environmentally sustainable. What is lacking is a cohesive framework for bringing these calls together. We propose that such transitions could be informed by lessons from three decades of scholarship on abrupt and surprising change in systems of humans and nature. Over time, many social-ecological systems exhibit cycles of change consisting of sequential patterns of growth, development, crisis, and reorganization. A critical phase in the cycle is the brief period after crisis when novelty and innovation can change the future trajectory. Without being prepared for this window of opportunity, deep, systemic change may be unachievable. We propose a three-step process to identify the major drivers of the global system that need to be changed: (1) identifying what society values; (2) identifying the determinants of these valued variables; and (3) identifying the underlying drivers of the determinants and how they need to be changed. A tentative list of five such drivers are identified and discussed: (i) the economic system, (ii) homogenization, (iii) human population growth, size, and densities, (iv) consumption patterns, human ethics, and behavior, and (v) governance. They are linked to seven questions relating to how we might proceed in addressing the drivers. If response to the crisis merely reinforces the existing system, its incompatibility with the natural world and its propensity to increase inequity and conflict will likely increase fragility and lead to another version of the present calamity. If it is a deliberately transformed system that emerges its future will depend on the reorganization process, and the way the system is guided into the future. What is needed is a deliberate, fundamental cultivation of emergence to enable transformation toward better futures in order to avoid an inevitable deepening of a system that ultimately is worse for all.

Regime shifts, i.e., large, persistent, and usually unexpected changes in ecosystems and social-ecological systems, can have major impacts on ecosystem services, and consequently, on human well-being. However, the vulnerability of different regions to various regime shifts is largely unknown because evidence for the existence of regime shifts in different ecosystems and parts of the world is scattered and highly uneven. Furthermore, research tends to focus on individual regime shifts rather than comparisons across regime shifts, limiting the potential for identifying common drivers that could reduce the risk of multiple regime shifts simultaneously. Here, we introduce the Regime Shifts Database, an open-access database that systematically synthesizes information on social-ecological regime shifts across a wide range of systems using a consistent, comparative framework, providing a wide-ranging information resource for environmental planning, assessment, research, and teaching initiatives. The database currently contains 28 generic types of regime shifts and > 300 specific case studies. Each entry provides a literature-based synthesis of the key drivers and feedbacks underlying the regime shift, as well as impacts on ecosystem services and human well-being, and possible management options. Across the 28 regime shifts, climate change and agriculture-related activities are the most prominent among a wide range of drivers. Biodiversity, fisheries, and aquatic ecosystems are particularly widely affected, as are key aspects of human well-being, including livelihoods, food and nutrition, and an array of cultural ecosystem services. We hope that the database will stimulate further research and teaching on regime shifts that can inform policy and practice and ultimately enhance our collective ability to manage and govern large, abrupt, systemic changes in the Anthropocene.

The emerging discipline of sustainability science is focused explicitly on the dynamic interactions between nature and society and is committed to research that spans multiple scales and can support transitions toward greater sustainability. Because a growing body of place-based social-ecological sustainability research (PBSESR) has emerged in recent decades, there is a growing need to understand better how to maximize the effectiveness of this work. The Programme on Ecosystem Change and Society (PECS) provides a unique opportunity for synthesizing insights gained from this research community on key features that may contribute to the relative success of PBSESR. We surveyed the leaders of PECS-affiliated projects using a combination of open, closed, and semistructured questions to identify which features of a research project are perceived to contribute to successful research design and implementation. We assessed six types of research features: problem orientation, research team, and contextual, conceptual, methodological, and evaluative features. We examined the desirable and undesirable aspects of each feature, the enabling factors and obstacles associated with project implementation, and asked respondents to assess the performance of their own projects in relation to these features. Responses were obtained from 25 projects working in 42 social-ecological study cases within 25 countries. Factors that contribute to the overall success of PBSESR included: explicitly addressing integrated social-ecological systems; a focus on solution- and transformation-oriented research; adaptation of studies to their local context; trusted, long-term, and frequent engagement with stakeholders and partners; and an early definition of the purpose and scope of research. Factors that hindered the success of PBSESR included: the complexities inherent to social-ecological systems, the imposition of particular epistemologies and methods on the wider research group, the need for long periods of time to initiate and conduct this kind of research, and power asymmetries both within the research team and among stakeholders. In the self-assessment exercise, performance relating to team and context-related features was ranked higher than performance relating to methodological, evaluation, and problem orientation features. We discuss how these insights are relevant for balancing place-based and global perspectives in sustainability science, fostering more rapid progress toward inter- and transdisciplinary integration, redefining and measuring the success of PBSESR, and facing the challenges of academic and research funding institutions. These results highlight the valuable opportunity that the PECS community provides in helping build a community of practice for PBSESR.

The concept of resilience is currently being widely promoted and applied by environmental and development organizations. However, their application of resilience often lacks theoretical backing and evaluation. This paper presents a novel cross-fertilization of two commonly used approaches for applying resilience thinking: the grassroots movement of Transition Towns and the Resilience Alliance's Resilience Assessment. We compared these approaches through a text analysis of their key handbooks and combined them in a series of participatory workshops with a local partner active in the Transition Movement. Our results demonstrate that despite sharing a number of key features, these two approaches have complementary strengths and weaknesses. Strengths of the Transition Movement include its motivating overarching narrative of the need to transform in response to global sustainability challenges, as well as practical tools promoting learning and participation. The Resilience Assessment's conceptual framework and structured process generated context-specific understanding of resilience, but provided little guidance on navigating transformation processes. Combining the Resilience Assessment's theory on complex systems with the Transition Movement's methods for learning also generated synergies in fostering complexity thinking. Based on these findings, we believe that integrating strengths from both approaches could be widely useful for practitioners seeking to apply resilience for sustainable development. Our study also highlights that methods for assessing resilience can be improved by combining insights from science and practice.

Ecosystem service assessment and management are shaped by the scale at which they are conducted; however, there has been little systematic investigation of the scales associated with ecosystem service processes, such as production, benefit distribution, and management. We examined how social-ecological spatial scale impacts ecosystem service assessment by comparing how ecosystem service distribution, trade-offs, and bundles shift across spatial scales. We used a case study in Québec, Canada, to analyze the scales of production, consumption, and management of 12 ecosystem services and to analyze how interactions among 7 of these ecosystem services change across 3 scales of observation (1, 9, and 75 km²). We found that ecosystem service patterns and interactions were relatively robust across scales of observation; however, we identified 4 different types of scale mismatches among ecosystem service production, consumption, and management. Based on this analysis, we have proposed 4 aspects of scale that ecosystem service assessments should consider.

In human dominated landscapes many diverse, and often antagonistic, human activities are intentionally and inadvertently determining the supply of various ecosystem services. Understanding how different social and ecological factors shape the availability of ecosystem services is essential for fair and effective policy and management. In this paper, we evaluate how well alternative social-ecological models of human impact on ecosystems explain patterns of 16 ecosystem services (ES) across the 62 municipalities of the Norrström drainage basin in Sweden. We test four models of human impact on ecosystems, land use, ecological modernization, ecological footprint, and location theory, and test their ability to predict both individual ES and bundles of ES. We find that different models do best to predict different types of individual ES. Land use is the best model for predicting provisioning services, standing water quality, biodiversity appreciation, and cross-country skiing, while other models work better for the remaining services. However, this range of models is not able to predict some of the cultural ES. ES bundles are predicted worse than individual ES by these models, but provide a clear picture of variation in multiple ecosystem services based on limited information. Based on our results, we offer suggestions on how social-ecological modeling and assessments of ecosystems can be further developed.

Participatory scenario planning (PSP) is an increasingly popular tool in place-based environmental research for evaluating alternative futures of social-ecological systems. Although a range of guidelines on PSP methods are available in the scientific and grey literature, there is a need to reflect on existing practices and their appropriate application for different objectives and contexts at the local scale, as well as on their potential perceived outcomes. We contribute to theoretical and empirical frameworks by analyzing how and why researchers assess social-ecological systems using place-based PSP, hence facilitating the appropriate uptake of such scenario tools in the future. We analyzed 23 PSP case studies conducted by the authors in a wide range of social-ecological settings by exploring seven aspects: (1) the context; (2) the original motivations and objectives; (3) the methodological approach; (4) the process; (5) the content of the scenarios; (6) the outputs of the research; and (7) the monitoring and evaluation of the PSP process. This was complemented by a reflection on strengths and weaknesses of using PSP for the place-based social-ecological research. We conclude that the application of PSP, particularly when tailored to shared objectives between local people and researchers, has enriched environmental management and scientific research through building common understanding and fostering learning about future planning of social-ecological systems. However, PSP still requires greater systematic monitoring and evaluation to assess its impact on the promotion of collective action for transitions to sustainability and the adaptation to global environmental change and its challenges.

Recent global crises reveal an emerging pattern of causation that could increasingly characterize the birth and progress of future global crises. A conceptual framework identifies this pattern’s deep causes, intermediate processes, and ultimate outcomes. The framework shows how multiple stresses can interact within a single social-ecological system to cause a shift in that system’s behavior, how simultaneous shifts of this kind in several largely discrete social-ecological systems can interact to cause a far larger intersystemic crisis, and how such a larger crisis can then rapidly propagate across multiple system boundaries to the global scale. Case studies of the 2008-2009 financial-energy and food-energy crises illustrate the framework. Suggestions are offered for future research to explore further the framework’s propositions.

Cities and towns have become increasingly interested in building resilience to cope with surprises, however, how to do this is often unclear. We evaluated the ability of the Resilience Assessment Workbook to help urban areas incorporate resilience thinking into their planning practice by exploring how a resilience assessment process complemented existing planning in the local government of Eskilstuna, Sweden. We conducted this evaluation using participant observation, semistructured interviews, and a survey of the participants. Our findings show that the resilience assessment contributed to ongoing planning practices by addressing sustainability challenges that were not being addressed within the normal municipal planning or operations, such as local food security. It bridged longer term sustainable development and shorter term crisis management, allowing these two sectors to develop common strategies. Our study also highlighted that the Resilience Assessment Workbook could be made more useful by providing more guidance on how to practically deal with thresholds and trade-offs across scales, as well as on how to manage transdisciplinary learning processes. This is the first in-depth study of a resilience assessment process, and it demonstrates that the Resilience Assessment Workbook is useful for planning and that it merits further research and development.

This study examines how ecosystem services (ES) have been taken into account historically in strategic spatial plans in Melbourne and Stockholm through a comparative case study analysis of eight strategic spatial plans from 1929-2010. We investigated the types of ES taken into account, and how human-nature relations and the valuation and trade-off discussions regarding ES were framed. An ES coding protocol was developed that categorized and identified 39 ES drawing from the Millennium Ecosystem Assessment and other relevant literature. Only two of the 39 ES were addressed in every plan for both cities, namely freshwater and recreation. While the number of ES referred to in plans has generally increased over time, just under a third of ES in Melbourne and Stockholm were not addressed at all. References to individual ES showed little continuity over time. This variability reveals a time-scale mismatch that has been overlooked in the ES literature with potential urban policy implications. Despite considerable variation in ES addressed across the plans, there is a striking similar pattern in the total numbers of ES addressed over time in both cities. Plans for both cities showed a spike in the late 60s/early 70s, followed by a significant decline in the late 70s/early 80s with the highest number of ES addressed in the most recent plans. Furthermore, our analysis shows that strategic spatial plans generally demonstrate awareness that urban populations are dependent on ecosystems and this framing is an important part of the policy discourse. While specific monetary values were not placed on any ES in the plans, resolution of land-use conflicts requiring tradeoffs between ES and equity of distribution of ES is a central feature of most of the examined plans. We argue that longitudinal policy document analysis represents a useful complement to any attempt to improve understanding of the implications of and opportunities for operationalizing an ES approach in urban practice.

Different uses of the terms "drivers," "variables," and "shocks" cause confusion in the literature and in discussions on the dynamics of ecosystems and social-ecological systems. Three main sources of confusion are unclear definition of the system, unclear definition of the role of people, and confusion between variables and drivers. As a contribution to resolving some of the confusion, we offer one interpretation of how the terms might be used.

In many densely settled agricultural watersheds, water quality is a point of conflict between amenity and agricultural activities because of the varied demands and impacts on shared water resources. Successful governance of these watersheds requires coordination among different activities. Recent research has highlighted the role that social networks between management entities can play to facilitate cross-scale interaction in watershed governance. For example, bridging organizations can be positioned in social networks to bridge local initiatives done by single municipalities across whole watersheds. To better understand the role of social networks in social-ecological system dynamics, we combine a social network analysis of the water quality management networks held by local governments with a social-ecological analysis of variation in water management and ecosystem services across the Montérégie, an agricultural landscape near Montréal, Québec, Canada. We analyze municipal water management networks by using one-mode networks to represent direct collaboration between municipalities, and two-mode networks to capture how bridging organizations indirectly connect municipalities. We find that municipalities do not collaborate directly with one another but instead are connected via bridging organizations that span the water quality management network. We also discovered that more connected municipalities engaged in more water management activities. However, bridging organizations preferentially connected with municipalities that used more tourism related ecosystem services rather than those that used more agricultural ecosystem services. Many agricultural municipalities were relatively isolated, despite being the main producers of water quality problems. In combination, these findings suggest that further strengthening the water management network in the Montérégie will contribute to improving water quality in the region. However, such strengthening requires developing a network that better connects both agricultural and tourism oriented municipalities. Furthermore, these findings show that consideration of the social-ecological context of social networks, can help explain the structure of networks and reveal social-ecological clusters and disconnects in a network.

The agro-ecosystems of semi-arid and dry sub-humid SSA are inherently dynamic. At this point in time they are also experiencing a series of complex social-ecological changes that make their future even more uncertain. To ensure that development investments made today in the small-scale farming systems that dominate these regions make sense also in a long-term perspective they should benefit the local communities over a range of potential futures. We applied a participatory scenario planning approach to a smallholder farming community in semi-arid Tanzania, exploring four alternative development trajectories for the area, to increase the robustness of current investments in small-scale water system technologies. We found that water system technologies will be important across a number of possible futures, but that the most relevant target of these innovations, e.g., staple- versus cash-crop production, or individual- versus community-managed systems, differs. We argue that building capacity for experimentation among farmers is key to upgrading their farming systems, as this will generate benefits over a range of alternative futures. Furthermore, we found it to be essential across a range of scenarios to analyze the system-level impact of proposed interventions for successful investments in water system technologies. We conclude that although the method presents some challenges, participatory scenario planning is a useful tool for integrating research and development projects in the larger context, asit increases the understanding of events and processes that may either challenge the project or provide opportunities for it.

This paper outlines the qualitative components (the storylines) of the Millennium Ecosystem Assessment (MA) scenarios. Drawing on a mixture of expert knowledge, experience, and published literature, we have explored plausible consequences of four trajectories for human development. The storylines have been designed to draw out both benefits and risks for ecosystems and human well-being in all four trajectories with enough richness of detail to allow readers to immerse themselves in the world of the scenario. Only a summarized version of the storylines is presented here; readers are encouraged to read the more detailed versions (MA 2005). Together with the quantitative models (Alcamo et al. 2005) the storylines provide a base from which others can consider implications for policy and practice in more depth, adding their own interpretations, experience, and imagination. This is the purpose of the following papers in this volume.

The Millennium Ecosystem Assessment (MA) scenarios address changes in ecosystem services and their implications for human well-being. Ecological changes pose special challenges for long-term thinking, because of the possibility of regime shifts that occur rapidly yet alter the availability of ecosystem services for generations. Moreover, ecological feedbacks can intensify human modification of ecosystems, creating a spiral of poverty and ecosystem degradation. Such complex dynamics were evaluated by a mixture of qualitative and quantitative analyses in the MA scenarios. Collectively, the scenarios explore problems such as the connections of poverty reduction and ecosystem services, and trade-offs among ecosystem services. Several promising approaches are considered by the scenarios, including uses of biodiversity to build resilience of ecosystem services, actively adaptive management, and green technology. Although the scenarios do not prescribe an optimal path, they illuminate the consequences of different policies toward ecosystem services.

Ecosystem service (ES) trade-offs arise from management choices made by humans, which can change the type, magnitude, and relative mix of services provided by ecosystems. Trade-offs occur when the provision of one ES is reduced as a consequence of increased use of another ES. In some cases, a trade-off may be an explicit choice; but in others, trade-offs arise without premeditation or even awareness that they are taking place. Trade-offs in ES can be classified along three axes: spatial scale, temporal scale, and reversibility. Spatial scale refers to whether the effects of the trade-off are felt locally or at a distant location. Temporal scale refers to whether the effects take place relatively rapidly or slowly. Reversibility expresses the likelihood that the perturbed ES may return to its original state if the perturbation ceases. Across all four Millennium Ecosystem Assessment scenarios and selected case study examples, trade-off decisions show a preference for provisioning, regulating, or cultural services (in that order). Supporting services are more likely to be "taken for granted." Cultural ES are almost entirely unquantified in scenario modeling; therefore, the calculated model results do not fully capture losses of these services that occur in the scenarios. The quantitative scenario models primarily capture the services that are perceived by society as more important - provisioning and regulating ecosystem services - and thus do not fully capture trade-offs of cultural and supporting services. Successful management policies will be those that incorporate lessons learned from prior decisions into future management actions. Managers should complement their actions with monitoring programs that, in addition to monitoring the short-term provisions of services, also monitor the long-term evolution of slowly changing variables. Policies can then be developed to take into account ES trade-offs at multiple spatial and temporal scales. Successful strategies will recognize the inherent complexities of ecosystem management and will work to develop policies that minimize the effects of ES trade-offs.

The Northern Highlands Lake District of Wisconsin is in transition from a sparsely settled region to a more densely populated one. Expected changes offer benefits to northern Wisconsin residents but also threaten to degrade the ecological services they rely on. Because the future of this region is uncertain, it is difficult to make decisions that will avoid potential risks and take advantage of potential opportunities. We adopt a scenario planning approach to cope with this problem of prediction. We use an ecological assessment framework developed by the Millennium Ecosystem Assessment to determine key social and ecological driving forces in the Northern Highlands Lake District. From these, we describe three alternative scenarios to the year 2025 in which the projected use of ecological services is substantially different. The work reported in this paper demonstrates how scenarios can be developed for a region and provides a starting point for a participatory discussion of alternative futures for northern Wisconsin. Although the future is unknowable, we hope that the assessment process begun in this paper will help the people of the Northern Highlands Lake District choose the future path of their region.

Although ecological managers typically focus on managing local or regional landscapes, they often have little ability to control or predict many of the large-scale, long-term processes that drive changes within these landscapes. This lack of control has led some ecologists to argue that ecological management should aim to produce ecosystems that are resilient to change and surprise. Unfortunately, ecological resilience is difficult to measure or estimate in the landscapes people manage. In this paper, I extend system dynamics approaches to resilience and estimate resilience using complex landscape simulation models. I use this approach to evaluate cross-scale edge, a novel empirical method for estimating resilience based on landscape pattern. Cross-scale edge provides relatively robust estimates of resilience, suggesting that, with some further development, it could be used as a management tool to provide rough and rapid estimates of areas of resilience and vulnerability within a landscape.

Approaches to natural resource management are often based on a presumed ability to predict probabilistic responses to management and external drivers such as climate. They also tend to assume that the manager is outside the system being managed. However, where the objectives include long-term sustainability, linked social-ecological systems (SESs) behave as complex adaptive systems, with the managers as integral components of the system. Moreover, uncertainties are large and it may be difficult to reduce them as fast as the system changes. Sustainability involves maintaining the functionality of a system when it is perturbed, or maintaining the elements needed to renew or reorganize if a large perturbation radically alters structure and function. The ability to do this is termed "resilience." This paper presents an evolving approach to analyzing resilience in SESs, as a basis for managing resilience. We propose a framework with four steps, involving close involvement of SES stakeholders. It begins with a stakeholder-led development of a conceptual model of the system, including its historical profile (how it got to be what it is) and preliminary assessments of the drivers of the supply of key ecosystem goods and services. Step 2 deals with identifying the range of unpredictable and uncontrollable drivers, stakeholder visions for the future, and contrasting possible future policies, weaving these three factors into a limited set of future scenarios. Step 3 uses the outputs from steps 1 and 2 to explore the SES for resilience in an iterative way. It generally includes the development of simple models of the system's dynamics for exploring attributes that affect resilience. Step 4 is a stakeholder evaluation of the process and outcomes in terms of policy and management implications. This approach to resilience analysis is illustrated using two stylized examples.

The benefits and risks of any particular GM crop depend on the interactions of its ecological functions and natural history with the agroecosystem and ecosystems within which it is embedded. These evolutionary and ecological factors must be considered when assessing GM crops. We argue that the assessment of GM crops should be broadened to include alternative agricultural practices, ecosystem management, and agricultural policy. Such an assessment would be facilitated by a clearer understanding of the indirect costs of agriculture and the ecological services that support it. The benefits of GM crops should be compared to those of other means of agricultural intensification such as organic farming, integrated pest management, and agricultural policy reform. A gradual and cautious approach to the use of GM crops that relies on a truly comprehensive risk assessment could allow people to reap substantial benefits from GM crops while mitigating their serious risks.