We characterized wildfire transmission and exposure within a matrix of large land tenures (federal, state, and private) surrounding 56 communities within a 3.3 million ha fire prone region of central ...Oregon US. Wildfire simulation and network analysis were used to quantify the exchange of fire among land tenures and communities and analyze the relative contributions of human versus natural ignitions to wildfire exposure. Among the land tenures examined, the area burned by incoming fires averaged 57% of the total burned area. Community exposure from incoming fires ignited on surrounding land tenures accounted for 67% of the total area burned. The number of land tenures contributing wildfire to individual communities and surrounding wildland urban interface (WUI) varied from 3 to 20. Community firesheds, i.e. the area where ignitions can spawn fires that can burn into the WUI, covered 40% of the landscape, and were 5.5 times larger than the combined area of the community core and WUI. For the major land tenures within the study area, the amount of incoming versus outgoing fire was relatively constant, with some exceptions. The study provides a multi-scale characterization of wildfire networks within a large, mixed tenure and fire prone landscape, and illustrates the connectivity of risk between communities and the surrounding wildlands. We use the findings to discuss how scale mismatches in local wildfire governance result from disconnected planning systems and disparate fire management objectives among the large landowners (federal, state, private) and local communities. Local and regional risk planning processes can adopt our concepts and methods to better define and map the scale of wildfire risk from large fire events and incorporate wildfire network and connectivity concepts into risk assessments.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The growing scale of natural hazards highlights the need for models of governance capable of addressing risk across administrative boundaries. However, risk governance systems are often fragmented, ...decentralized, and sustained by informal linkages among local-level risk mitigation planning processes. Improving resilience to the effects of environmental change requires a better understanding of factors that contribute to these linkages. Using data on the patterns of participation of 10,199 individual stakeholders in 837 community wildfire protection plans (CWPPs) within the western U.S., we document the emergence of a locally clustered but spatially extensive wildfire risk governance network. Our evaluation of factors that contribute to connectivity within this network indicates that risk interdependence (e.g., joint exposure to the same fires) between planning jurisdictions increases the prospects for linkages between planning processes, and that connectivity is also more likely among planning processes that are more proximate and similar to one another. We discuss how our results advance understanding of how changing hazard conditions prompt risk mitigation policy networks to reorganize, which in turn affects risk outcomes at multiple spatial scales.
We assessed transboundary wildfire exposure among federal, state, and private lands and 447 communities in the state of Arizona, southwestern United States. The study quantified the relative ...magnitude of transboundary (incoming, outgoing) versus nontransboundary (i.e., self‐burning) wildfire exposure based on land tenure or community of the simulated ignition and the resulting fire perimeter. We developed and described several new metrics to quantify and map transboundary exposure. We found that incoming transboundary fire accounted for 37% of the total area burned on large parcels of federal and state lands, whereas 63% of the area burned was burned by ignitions within the parcel. However, substantial parcel to parcel variation was observed for all land tenures for all metrics. We found that incoming transboundary fire accounted for 66% of the total area burned within communities versus 34% of the area burned by self‐burning ignitions. Of the total area burned within communities, private lands contributed the largest proportion (36.7%), followed by national forests (19.5%), and state lands (15.4%). On average seven land tenures contributed wildfire to individual communities. Annual wildfire exposure to structures was highest for wildfires ignited on state and national forest land, followed by tribal, private, and BLM. We mapped community firesheds, that is, the area where ignitions can spawn fires that can burn into communities, and estimated that they covered 7.7 million ha, or 26% of the state of Arizona. Our methods address gaps in existing wildfire risk assessments, and their implementation can help reduce fragmentation in governance systems and inefficiencies in risk planning.
This paper examines the issue of radionuclide resuspension from wildland fires in areas contaminated by the Chernobyl Nuclear Power Plant explosion in 1986. This work originated from a scientific ...exchange among scientists from the USDA Forest Service, Ukraine and Belarus that was organized to assess science and technology gaps related to wildfire risk management. A wildfire risk modeling system was developed to predict likely hotspots for large fires and where wildfire ignitions will most likely result in significant radionuclide (Cesium, 137Cs) resuspension. The system was also designed to examine the effect of fuel breaks in terms of reducing both burn probability and resuspension. Results showed substantial spatial variation in fire likelihood, size, intensity, and potential resuspension within the contaminated areas. The potential for a large wildfire and resuspension was highest in the Belorussian Polesie Reserve, but the likelihood of such an event was higher in the Ukrainian Chernobyl Exclusion Zone due to a higher predicted probability of ignition. Fuel breaks were most effective in terms of reducing potential resuspension when located near areas that had both high ignition probability and high levels of 137Cs contamination. Simulation outputs highlighted how human activities shape the fire regime and likelihood of a large fire in the contaminated areas. We discuss how the results can be used to develop a fire management strategy that integrates ignition prevention, detection, effective suppression response, and fuel breaks. Specifically, the modeling system can now be used to explore a wide range of fire management scenarios for the contaminated areas and contribute to a comprehensive fire management strategy that targets specific drivers of fire by leveraging multiple tools including fire prevention and long-term fuel management. Wildfire-caused emissions of radionuclides in Belarus, Ukraine, and Russia are a socio-ecological problem that will require defragmenting existing risk management systems and leveraging multiple short- and long-term mitigation measures.
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•Wildfires are of growing concern in Chernobyl contaminated areas.•Resuspension of radionuclides from wildfires has potential adverse health effects.•We built a wildfire simulation system to predict risk of fires and resuspension.•The results revealed hotspots for fire ignitions and resuspension.•Targeted fuel breaks and ignition prevention could reduce future resuspension.
•We mapped wildfire risk transmission from national forests to the WUI.•We examined management restrictions on areas with high transmission.•Most transmission originated from areas where mechanical ...fuel treatments are permitted.•Forest restoration with mechanical treatments is compatible with WUI protection.•Mapping risk transmission facilitates identification of conflicts and opportunities.
We analyzed the impact of amenity and biodiversity protection as mandated in national forest plans on the implementation of hazardous fuel reduction treatments aimed at protecting the wildland urban interface (WUI) and restoring fire resilient forests. We used simulation modeling to delineate areas on national forests that can potentially transmit fires to adjacent WUI. We then intersected these areas with national forest planning maps to determine where mechanical treatments are allowed for restoration and fire protection, versus areas where they are prohibited. We found that a large proportion of the national forest lands (79%) can spawn fires that burn adjacent WUIs. The bulk of the predicted WUI exposure originated from simulated fires ignited outside of conservation and preservation reserves and in dry forests, rather than moist mixed conifer forests. Thus the notion that fuel buildup in reserves on national forests contributes to wildfire risk in the urban interface was only partially supported by the data for the region studied. Most of the national forest lands that contribute wildfires to the WUI are not within the boundaries of community wildfire protection plans, which may undermine the effectiveness of these planning efforts. We used the spatial data themes developed in the study to map conflicts and opportunities for restoration and mitigation of WUI wildfire risk. The analysis disentangles the spatial complexity of managing landscapes for multiple socio-ecological objectives as part of ongoing restoration programs, collaborative planning, and national forest plan revisions on national forests in the US.
We provide the wildland urban interface (WUI) map of the autonomous community of Catalonia (Northeastern Spain). The map encompasses an area of some 3.21 million ha and is presented as a 150-m ...resolution raster dataset. Individual housing location, structure density and vegetation cover data were used to spatially assess in detail the interface, intermix and dispersed rural WUI communities with a geographical information system. Most WUI areas concentrate in the coastal belt where suburban sprawl has occurred nearby or within unmanaged forests. This geospatial information data provides an approximation of residential housing potential for loss given a wildfire, and represents a valuable contribution to assist landscape and urban planning in the region.
We integrated a mechanistic wildfire simulation system with an agent-based landscape change model to investigate the feedbacks among climate change, population growth, development, landowner ...decision-making, vegetative succession, and wildfire. Our goal was to develop an adaptable simulation platform for anticipating risk-mitigation tradeoffs in a fire-prone wildland–urban interface (WUI) facing conditions outside the bounds of experience. We describe how five social and ecological system (SES) submodels interact over time and space to generate highly variable alternative futures even within the same scenario as stochastic elements in simulated wildfire, succession, and landowner decisions create large sets of unique, path-dependent futures for analysis. We applied the modeling system to an 815 km2 study area in western Oregon at a sub-taxlot parcel grain and annual timestep, generating hundreds of alternative futures for 2007–2056 (50 years) to explore how WUI communities facing compound risks from increasing wildfire and expanding periurban development can situate and assess alternative risk management approaches in their localized SES context. The ability to link trends and uncertainties across many futures to processes and events that unfold in individual futures is central to the modeling system. By contrasting selected alternative futures, we illustrate how assessing simulated feedbacks between wildfire and other SES processes can identify tradeoffs and leverage points in fire-prone WUI landscapes. Assessments include a detailed “post-mortem” of a rare, extreme wildfire event, and uncovered, unexpected stabilizing feedbacks from treatment costs that reduced the effectiveness of agent responses to signs of increasing risk.
We report a fine-scale assessment of cross-boundary
wildfire events for the western US. We used simulation modeling to quantify
the extent of fire exchange among major federal, state, and private ...land
tenures and mapped locations where fire ignitions can potentially affect
populated places. We examined how parcel size affects wildfire transmission
and partitioned the relative amounts of transmitted fire between human and
natural ignitions. We estimated that 85 % of the total predicted wildfire
activity, as measured by area burned, originates from four land tenures
(Forest Service, Bureau of Land Management, private, and state lands) and
63 % of the total amount results from natural versus human ignitions. On
average, one-third of the area burned by predicted wildfires was nonlocal,
meaning that the source ignition was on a different land tenure. Land
tenures with smaller parcels tended to receive more incoming fire on a
proportional basis, while the largest fires were generated from ignitions in
national parks, national forests, and public and tribal lands. Among the 11
western states, the amount and pattern of cross-boundary fire varied
substantially in terms of which land tenures were mostly exposed, by whom,
and to what extent. We also found spatial variability in terms of community
exposure among states, and more than half of the predicted structure
exposure was caused by ignitions on private lands or within the
wildland–urban interface areas. This study addressed gaps in existing
wildfire risk assessments that do not explicitly consider cross-boundary
fire transmission and do not identify the source of fire. The results can be
used by state, federal, and local fire planning organizations to help
improve risk mitigation programs.
Scientists, policy makers, and managers use ecosystem services and biodiversity metrics to inform management goals of novel ecosystems. Fragmented knowledge of the ecosystem services provided by ...novel ecosystems contributes to disagreement over these systems and how they should be managed. To address this gap, we conducted a systematic review of refereed articles to understand how novel ecosystems have changed ecosystem services and biodiversity. Despite anthropogenic drivers of change, we found that the literature on novel ecosystems is focused on ecological rather than social aspects of novel systems. Our review highlights the frequency that novel ecosystems enhance both ecosystem services and biodiversity. More than two-thirds of studies reported biodiversity equal to or above the reference state, while the portion of studies reporting increased cultural, provisioning, and regulating services was even greater. Still, we urge caution in interpreting these trends, as they exist in part due to degraded ecosystem baselines and inconsistent framing. Finally, the wide range of management recommendations we reviewed reflects both the diversity of novel ecosystems and substantial disagreement among researchers and managers about what novel ecosystems actually mean for society.
•Wildfire simulations combined with US census variables revealed the degree of exposure of socially vulnerable populations.•In Central California, most of the estimated structure exposure was ...predicted to originate from the Wildland-Urban Interface and private lands.•A third of structure exposure on highly socially vulnerable places in New Mexico originates from Federal lands.•National forest simulated ignitions mostly affect the socially vulnerable communities of North-central Washington.•Socially vulnerable communities in Northern New Mexico are mostly affected from ignitions in other communities, Federal and tribal lands.
Federal land managers in the US can be informed with quantitative assessments of the social conditions of the populations affected by wildfires originating on their administered lands in order to incorporate and adapt their management strategy to achieve a more targeted prioritization of community wildfire protection investments. In addition, these assessments are valuable to socially vulnerable communities for quantifying their exposure to wildfires originating on adjacent land tenures. We assessed fire transmission patterns using fire behavior simulations to understand spatial variations across three diverse study areas (North-central Washington; Central California; and Northern New Mexico) to understand how different land tenures affect highly socially vulnerable populated places. Transboundary wildfire structure exposure was related to populations with limited adaptive capacity to absorb, recover and modify exposure to wildfires, estimated with the Social Vulnerability Index using US Census unit data (block groups). We found geographic heterogeneity in terms of land tenure composition and estimated fire exposure. Although high social vulnerability block groups covered small areas, they had high population and structure density and were disproportionately exposed per area burned by fire. Structure exposure originated primarily from three key land tenures (wildland-urban interface, private lands and national forests). Federal lands proportionately exposed, on an area basis, populated places with high social vulnerability, with fires ignited on Forest Service administered lands mostly affecting north-central Washington and northern New Mexico communities.
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