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I. The Context: The Highly Fragmented Midwest -- 1. Forest Communities of the Midwestern United States -- 2. Savanna and Open-Woodland Communities -- 3. The Tallgrass Prairie Mosaic -- 4. Wetlands in the Midwest with Special Reference to Illinois -- II. Problems and Case Studies -- 5. Conservation in the Context of Non-Indigenous Species -- 6. Native Pests: The Impact of Deer in Highly Fragmented Habitats -- 7. Mammals of Illinois and the Midwest: Ecological and Conservation Issues for Human-Dominated Landscapes -- 8. Effectiveness of Small Nature Preserves for Breeding Birds -- 9. Impacts of Fragmentation on Midwestern Aquatic Organisms -- 10. Midwestern Fire Management: Prescribing a National Process in an Unnatural Landscape -- 11. Community Succession, Diversity, and Disturbance in the Central Hardwood Forest -- 12. The Biogeography of and Habitat Loss on Hill Prairies -- 13. Fragmentation and the Role of Seed Banks in Promoting Persistence in Isolated Populations of Collinsia verra -- 14. Effects of Livestock Grazing on Forest Habitats -- III. Conservation Strategies in Action -- 15. Terrestrial Nature Reserve Design at the Urban/Rural Interface -- 16. The Value of Small Preserves in Chronically Fragmented Landscapes -- 17. Nature Preserves, Natural Areas, and the Conservation of Endangered and Threatened Species in Illinois -- 18. An Aid to Conservation Strategy in Illinois: The Critical Trends Assessment Project -- 19. The History of Natural Areas Programs in Wisconsin.

Over the last decade, in response to the changing dynamics and increasing complexity and unpredictability of forced and irregular migration, there has been a significant remaking of the concept of protection, a diversification of the practice of protection and an expansion in the range of humanitarian and other actors doing protection work. In principle, at least, these developments have the potential to reduce the risks to which forced migrants are exposed and their vulnerability to those risks, and to allow people to flee conflict, violence and human rights abuses in security. However, this has led to a fragmented landscape of protection which is conceptually problematic, and which has divergent standards, procedures and governance. The result has been increasing vulnerability of forced migrants and a protection regime that lacks coherence and fairness. How to develop and adapt protection norms and practices that respond to profoundly different patterns and dynamics of population displacement in the contemporary world is the challenge that remains. Adapted from the source document.

Little theoretical work has investigated how landscape structure affects invasive spread, even though broad‐scale disturbances caused by habitat loss and fragmentation are believed to facilitate the spread of exotic species. Neutral landscape models (NLMs), derived from percolation theory in the field of landscape ecology, provide a tool for assessing the risk of invasive spread in fragmented landscapes. A percolation‐based analysis of the potential for invasive spread in fragmented landscapes predicts that invasive spread may be enormously enhanced beyond some threshold level of habitat loss, which depends upon the species' dispersal abilities and the degree of habitat fragmentation. Assuming that invasive species spread primarily through disturbed areas of the landscape, poor dispersers may spread better in landscapes in which disturbances are concentrated in space, whereas good dispersers are predicted to spread better in landscapes where disturbances are small and dispersed (i.e., fragmented landscape). Assessing the risk of invasive spread in fragmented landscapes ultimately requires understanding the relative effects of landscape structure on processes that contribute to invasive spread—dispersal (successful colonization) and demography (successful establishment). Colonization success is predicted to be highest when >20% of the landscape has been disturbed, particularly if disturbances are large or aggregated in space, because propagules are more likely to encounter sites suitable for colonization and establishment. However, landscape pattern becomes less important for predicting colonization success if species are capable of occasional long‐distance dispersal events. Invasive species are also more likely to persist and achieve positive population growth rates (successful establishment) in landscapes with clumped disturbance patterns, which can then function as population sources that produce immigrants that invade other landscapes. Finally, the invasibility of communities may be greatest in landscapes with a concentrated pattern of disturbance, especially below some critical threshold of biodiversity. Below the critical biodiversity threshold, the introduction of a single species can trigger a cascade of extinctions among indigenous species. The application of NLMs may thus offer new insights and opportunities for the management and restoration of landscapes so as to slow the spread of invasive species.

AbstractThe rapid advances in the development and rollout of artificial intelligence (AI) technologies over the past years have triggered a frenzy of regulatory initiatives at various levels of government and the private sector. This article describes and evaluates the emerging global AI governance architecture and traces the contours of a nascent regime in a fragmented landscape. To do so, it organizes actors and initiatives in a two-by-two matrix, distinguishing between the nature of the driving actor(s) and whether or not their actions take place within the existing governance architecture. Based on this, it provides an overview of key actors and initiatives, highlighting their trajectories and connections. The analysis shows international organizations' high levels of agency in addressing AI policy and a tendency to address new challenges within existing frameworks. Lastly, it is argued that we are witnessing the first signs of consolidation in this fragmented landscape. The nascent AI regime that emerges is polycentric and fragmented but gravitates around the Organisation for Economic Co-Operation and Development (OECD), which holds considerable epistemic authority and norm-setting power.

The rapid advances in the development and rollout of artificial intelligence (AI) technologies over the past years have triggered a frenzy of regulatory initiatives at various levels of government and the private sector. This article describes and evaluates the emerging global AI governance architecture and traces the contours of a nascent regime in a fragmented landscape. To do so, it organizes actors and initiatives in a two-by-two matrix, distinguishing between the nature of the driving actor(s) and whether or not their actions take place within the existing governance architecture. Based on this, it provides an overview of key actors and initiatives, highlighting their trajectories and connections. The analysis shows international organizations' high levels of agency in addressing AI policy and a tendency to address new challenges within existing frameworks. Lastly, it is argued that we are witnessing the first signs of consolidation in this fragmented landscape. The nascent AI regime that emerges is polycentric and fragmented but gravitates around the Organisation for Economic Co-Operation and Development (OECD), which holds considerable epistemic authority and norm-setting power. ; The author has received funding from the European Union's Horizon 2020 Research & Innovation programme under Grant Agreement no. 822654: Global Governance and the European Union: Future Trends and Scenarios (GLOBE).

Context Habitat loss and fragmentation are key drivers of biodiversity loss worldwide, yet the influence of landscape structure on species distributions is unknown. Globally, reptiles are thought to be especially sensitive to landscape modification due to their limited capacity for dispersal and reliance on native vegetation. New knowledge of how landscape structure influences species distributions is needed to inform conservation strategies. Aims Our principal aim was to examine the influence of landscape structure on the distributions of 40 terrestrial reptile species in Victoria, southeast Australia. Methods We obtained species occurrence records from the Victorian Biodiversity Atlas, and used MaxEnt to model the distributions of reptile species within Victoria using biophysical and landscape structure variables. A moving window analysis was applied to a land cover map to derive five landscape structure metrics; two metrics represented landscape cover and three represented landscape configuration. Key results Climate variables were generally found to be the strongest drivers of species distributions, although 80% of reptile species were also influenced by landscape structure (permutation importance ≥5%). Of the five landscape structure variables, extent of native vegetation had the greatest influence (30 of 40 species), followed by habitat shape. For Lerista bougainvillii and Tiliqua rugosa, native vegetation cover had a greater influence on their distributions than climate variables. Most species responded positively to native vegetation extent, whereas responses to other landscape structure variables were varied. Conclusions Although most studies of reptile distributions only use biophysical variables in modelling, our research shows that at the scale of our study area, reptile species distributions were also influenced by landscape structure; extent of native vegetation was an important predictor for most species. Integrating landscape structure in modelling has the potential to improve our ability to predict species distributions. Implications Because species distributions are likely to shift due to climate change, knowledge of the influence of landscape structure on distributions will help land managers to facilitate successful range expansions in fragmented landscapes. Our findings indicate that management focused on increasing the extent of native vegetation is likely to provide benefit to most reptile species.