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Protecting or restoring habitat connectivity in landscapes undergoing rapid environmental change requires multiple conservation and restoration strategies. These strategies have different risk profiles, costs, and require various types of technical expertise to conduct. This diversity in landscape context and strategic approach requires more nuance and flexibility than traditional connectivity conservation plans have supported. We present a novel, spatially‐explicit framework for developing connectivity conservation priorities and strategies based on Omniscape, an adaptation of Circuitscape, a common tool for mapping habitat connectivity. Using California (USA) as a case study, we mapped structural connectivity and developed a classification of connectivity conservation and restoration categories across the gradient of land use intensities, as well as by land ownership. The most constrained areas with highly concentrated flow (movement potential) make up 3% of the state and occur primarily on private lands. Conversely, intact areas with diffuse flow that indicate multiple connectivity options cover 55% of the state, including the majority of the desert and mountain ecoregions. This "strategy mapping" approach can be used to identify priority areas for conservation investment and suites of potential implementation mechanisms and partners, which in turn may improve the efficiency and effectiveness of connectivity conservation in this era of global change. [ABSTRACT FROM AUTHOR]

Human‐induced ecological boundaries, or anthropogenic ecotones, may arise where administrative boundaries meet on undeveloped lands. Landscape‐level ecological processes related to factors such as fire, invasive species, grazing, resource extraction, wildlife, and water may be affected due to unique management strategies adopted by each administrative unit. Over time, different management can result in discernible ecological differences (e.g., species composition or soil characteristics). Thus, fragmentation in the management landscape can correspond to ecological fragmentation. Different ecological patterns may emerge due to an increase in the number of management units in a region, or due to an increase in the number of different types of management units in the region. Temporal effects and collaboration history can also affect the emergence of ecotones. We use conceptual models to explore the relationship between these aspects of management fragmentation and the anthropogenic ecotones between management parcels. We then use examples of different management challenges to explore how anthropogenic ecotones can disrupt ecological flows. Our models suggest that cross‐boundary collaboration that enhances management connectivity is likely essential to ecological connectivity in the face of environmental and social change. [ABSTRACT FROM AUTHOR]

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Landscape connectivity is crucial for many ecological processes, including dispersal, gene flow, demographic rescue, and movement in response to climate change. As a result, governmental and non-governmental organizations are focusing efforts to map and conserve areas that facilitate movement to maintain population connectivity and promote climate adaptation. In contrast, little focus has been placed on identifying barriers-landscape features which impede movement between ecologically important areas-where restoration could most improve connectivity. Yet knowing where barriers most strongly reduce connectivity can complement traditional analyses aimed at mapping best movement routes. We introduce a novel method to detect important barriers and provide example applications. Our method uses GIS neighborhood analyses in conjunction with effective distance analyses to detect barriers that, if removed, would significantly improve connectivity. Applicable in least-cost, circuit-theoretic, and simulation modeling frameworks, the method detects both complete (impermeable) barriers and those that impede but do not completely block movement. Barrier mapping complements corridor mapping by broadening the range of connectivity conservation alternatives available to practitioners. The method can help practitioners move beyond maintaining currently important areas to restoring and enhancing connectivity through active barrier removal. It can inform decisions on trade-offs between restoration and protection; for example, purchasing an intact corridor may be substantially more costly than restoring a barrier that blocks an alternative corridor. And it extends the concept of centrality to barriers, highlighting areas that most diminish connectivity across broad networks. Identifying which modeled barriers have the greatest impact can also help prioritize error checking of land cover data and collection of field data to improve connectivity maps. Barrier detection provides a different way to view the landscape, broadening thinking about connectivity and fragmentation while increasing conservation options. [ABSTRACT FROM AUTHOR]

Widespread human modification and conversion of land has led to loss and fragmentation of natural ecosystems, altering ecological processes and causing declines in biodiversity. The potential for ecosystems to adapt to climate change will be contingent on the ability of species to move and ecological processes to operate across broad landscapes. We developed a novel, robust modeling approach to estimate the connectivity of natural landscapes as a gradient of permeability. Our approach yields a map capable of prioritizing places that are important for maintaining and potentially restoring ecological flows across the United States and informing conservation initiatives at regional, national, or continental scales. We found that connectivity routes with very high centrality intersected proposed energy corridors in the western United States at roughly 500 locations and intersected 733 moderate to heavily used highways (104-106 vehicles per day). Roughly 15% of the most highly connected locations are currently secured by protected lands, whereas 28% of these occur on public lands that permit resource extraction, and the remaining 57% are unprotected. The landscape permeability map can inform land use planning and policy about places potentially important for climate change adaptation. [ABSTRACT FROM AUTHOR]

Many organisms persist in fragmented habitat where movement between patches is essential for long-term demographic and genetic stability. In the absence of direct observation of movement, connectivity or isolation metrics are useful to characterize potential patch-level connectivity. However, multiple metrics exist at varying levels of complexity, and empirical data on species distribution are rarely used to compare performance of metrics. We compared 12 connectivity metrics of varying degrees of complexity to determine which metric best predicts the distribution of prairie dog colonies along an urban gradient of 385 isolated habitat patches in Denver, Colorado, USA. We found that a modified version of the incidence function model including area-weighting of patches and a cost-weighted distance surface best predicted occupancy, where we assumed roads were fairly impermeable to movement, and low-lying drainages provided dispersal corridors. We also found this result to be robust to a range of cost weight parameters. Our results suggest that metrics should incorporate both patch area and the composition of the surrounding matrix. These results provide guidance for improved landscape habitat modeling in fragmented landscapes and can help identify target habitat for conservation and management of prairie dogs in urban systems. [ABSTRACT FROM AUTHOR]

Abstract: Central Rondônia is one of the most deforested regions in the Brazilian Amazon and contains areas at different stages of degradation forming a gradient from mature forest to highly urbanized and built-up areas. Regional data from satellite imagery are available from the 1980s, but apart from studies that quantify deforestation, the broad-scale landscape dynamics of Rondônia have not been examined well. This paper assesses the landscape changes between 1984 and 2002 in a watershed located in the central region of the state of Rondônia, Brazil, which has undergone systematic and rapid deforestation due to introduction of pasture that began in the 1970s. Bi-annual Landsat TM/ETM+ images from 1984 to 2002 were classified into three broad land cover types: mature forest, secondary forest, and pasture, resulting in a time series of land-use/land-cover maps. Landscape changes were evaluated by computing a cross tabulation between years, transition rates, and landscape metrics related to size, density, connectivity, configuration, and deforested patches distribution related to patch size and spatial proximity to roads and old pastures. Transition probability functions were fitted to the temporal series to predict land-use changes for the next 10 years, for three different scenarios: (1) continued land-use change; (2) eliminating clear-cutting and selective logging; and (3) eliminating clear-cutting, selective logging, and secondary vegetation clearing. Current land-use transitions cannot be sustained beyond the next 10–15 years. A more sustainable scenario for the region requires a major reduction of deforestation activities, implementing the “permanent preservation area” policy along riversides, and controlling land-use transitions at balanced levels. We recommend that forest managers in regions facing similar deforestation pressures should strive to maintain at least 35% mature or primary forest, because landscape fragmentation proceeds rapidly below this critical threshold. [Copyright &y& Elsevier]

Fire-prone landscapes are increasingly being settled. Monitoring this development is an emerging need, and a low-cost method would benefit emergency managers. Existing change- detection methods can be expensive and time consuming when applied to low-density urban change in large, vegetated areas. Nighttime satellite imagery is explored as means for addressing this problem, and a case study is presented for Colorado. The results indicate that from 1992-2000, Grand County had the greatest absolute increase in ambient sprawl into fire-prone areas (215 km²), but Teller County had the greatest percentage increase (7.3 percent). In 2000, La Plata County had the most ambient development in fire-prone areas (909 km²), but Jefferson County had the greatest percentage (42 percent). The paper concludes with a discussion of the prospects and problems of the approach. [ABSTRACT FROM AUTHOR]

Describes a general approach to forecasting spatially explicit rural land-use change at the landscape scale. Two ways to model the spatial distribution of land-use change; Cellular automata theory; Basis of traditional urban and rural development models.