•Spatial optimization models are widely used in natural resource planning.•We critically examined recent literature comparing optimization methods.•Mathematical programming has become a more common ...approach in new planning systems.•Heuristics are more adaptable to a wider range of problems and less complex.•The relative merits of the alternative model approaches are discussed.
The long‐term outcome from accelerated forest restoration using resource objective wildfire in combination with fuel management on fire‐excluded landscapes is not well studied. We used simulation ...modeling to examine long‐term trade‐offs and synergies of alternative land management strategies by combining two wildfire management alternatives with three levels of contemporary forest restoration treatments on a 778,000‐ha landscape over 56 years. We found that managing wildfires for resource objectives diminished the likelihood of irregular fire events over time by making wildfire activity more predictable. Overall, adding resource objective wildfire reduced the proportion of high‐severity fire in relation to total area burned, but increased total area burned and the area of high‐severity fire. We also found resource objective wildfire changed the distribution of high‐severity burn patches by increasing their total number and range, their likelihood of containing disjunct core areas, and their edge complexity. The results suggested that alongside the current pace of active forest management, expanding the fire footprint to achieve low‐cost restoration carries the potential for increased high‐severity fire and associated impacts to ecological values including old forest structure and wildlife habitat. Concurrently, adding resource objective wildfire expanded the footprint of conventional restoration treatments by fivefold, and restoration objectives were achieved in 25 years when managing resource objective wildfires alongside restoration treatments five times the current pace. This study demonstrates the first fire suppression model to replicate local decision making by fire managers during simulated fire events to manage risk by considering both fire proximity to values at risk, and daily weather conditions. The study paves the way for further investigations of the synergies between wildfires and conventional forest restoration to improve resiliency in fire‐excluded pine forests.
Context
Restoring wide areas of fire excluded western US landscapes to fuel limited, fire resilient systems where fires self-regulate and burn with low or mixed severity will require expanded use of ...both prescribed and natural fire, coupled with strategic mechanical fuels management. However, optimal admixtures of fire and fuel management to set landscapes on trajectories to improve fire resilience and conserve carbon are not well understood.
Objectives
To understand the effect of accelerating restoration and fuel management in response to potential future fire regimes on a large fire excluded mixed-owner forest landscape.
Methods
We simulated 50-year wildfire and active forest management scenarios on a multi-owner landscape in southcentral Oregon, crossed in a factorial design with a range of wildfire and forest management intensities.
Results
Wildfire was more efficient at reducing potential high-severity fire, whereas restoration treatments created patches of fire resilient old forest, especially on federally managed land. With some exceptions, both disturbances reduced aboveground carbon over time, although the magnitude varied among the combinations of fire and active management intensities. We observed interactive effects from specific combinations of fire and management in landscape response metrics compared to stand-alone disturbances.
Conclusions
Fire and active management have similar landscape outcomes for some but not all restoration objectives, and active management will be required under future predicted fire regimes to conserve and create fire resilient old forest. Achieving widespread fire resilient forest structure will be limited by divergent landowner management behaviors on mixed-owner landscapes.
We modeled forest restoration scenarios to examine socioeconomic and ecological trade-offs associated with alternative prioritization scenarios. The study examined four US national forests designated ...as priorities for investments to restore fire resiliency and generate economic opportunities to support local industry. We were particularly interested in economic trade-offs that would result from prioritization of management activities to address forest departure and wildfire risk to the adjacent urban interface. The results showed strong trade-offs and scale effects on production possibility frontiers, and substantial variation among planning areas and national forests. The results pointed to spatially explicit priorities and opportunities to achieve restoration goals within the study area. However, optimizing revenue to help finance restoration projects led to a sharp reduction in the attainment of other socioecological objectives, especially reducing forest departure from historical conditions. The analytical framework and results can inform ongoing collaborative restoration planning to help stakeholders understand the opportunity cost of specific restoration objectives. This work represents one of the first spatially explicit, economic trade-off analyses of national forest restoration programs, and reveals the relative cost of different restoration strategies, as well scale-related changes in production frontiers associated with restoration investments.
The implementation of US federal forest restoration programs on national forests is a complex process that requires balancing diverse socioecological goals with project economics. Despite both the ...large geographic scope and substantial investments in restoration projects, a quantitative decision support framework to locate optimal project areas and examine tradeoffs among alternative restoration strategies is lacking. We developed and demonstrated a new prioritization approach for restoration projects using optimization and the framework of production possibility frontiers. The study area was a 914,657 ha national forest in eastern Oregon, US that was identified as a national priority for restoration with the goal of increasing fire resiliency and sustaining ecosystem services. The results illustrated sharp tradeoffs among the various restoration goals due to weak spatial correlation of forest stressors and provisional ecosystem services. The sharpest tradeoffs were found in simulated projects that addressed either wildfire risk to the urban interface or wildfire hazard, highlighting the challenges associated with meeting both economic and fire protection goals. Understanding the nature of tradeoffs between restoration objectives and communicating them to forest stakeholders will allow forest managers to more effectively design and implement economically feasible restoration projects.
Abstract
Climate change is expected to increase fire activity in many regions of the globe, but the relative role of human vs. lightning-caused ignitions on future fire regimes is unclear. We ...developed statistical models that account for the spatiotemporal ignition patterns by cause in the eastern slopes of the Cascades in Oregon, USA. Projected changes in energy release component from a suite of climate models were used with our model to quantify changes in frequency and extent of human and lightning-caused fires and record-breaking events based on sizes of individual fires between contemporary (2006 −2015) and mid-century conditions (2031–2060). No significant change was projected for the number of human-caused fire ignitions, but we projected a 14% reduction in lightning-caused ignitions under future conditions. Mean fire sizes were 31% and 22% larger under future conditions (2031–2060) for human and lightning-caused ignitions, respectively. All but one climate model projected increased frequency of record-breaking events relative to the contemporary period, with the largest future fires being about twice the size of those of the contemporary period. This work contributes to understanding the role of lightning- and human-caused fires on future fire regimes and can help inform successful adaptation strategies in this landscape.
Understanding ownership effects on large wildfires is a precursor to the development of risk governance strategies that better protect people and property and restore fire-adapted ecosystems. We ...analyzed wildfire events in the Pacific Northwest from 1984 to 2018 to explore how area burned responded to ownership, asking whether particular ownerships burned disproportionately more or less, and whether these patterns varied by forest and grass/shrub vegetation types. While many individual fires showed indifference to property lines, taken as a whole, we found patterns of disproportionate burning for both forest and grass/shrub fires. We found that forest fires avoided ownerships with a concentration of highly valued resources-burning less than expected in managed US Forest Service forested lands, private non-industrial, private industrial, and state lands-suggesting the enforcement of strong fire protection policies. US Forest Service wilderness was the only ownership classification that burned more than expected which may result from the management of natural ignitions for resource objectives, its remoteness or both. Results from this study are relevant to inform perspectives on land management among public and private entities, which may share boundaries but not fire management goals, and support effective cross-boundary collaboration and shared stewardship across all-lands.
We evaluated the spatiotemporal changes in wildfire regime and exposure in a fire-prone Mediterranean area (Sardinia, Italy) in relation to changes in ignition patterns, weather, suppression ...activities, and land uses. We also used wildfire simulations to identify fine-scale changes in wildfire exposure of important features on the island. Sardinia experienced a sharp reduction in fire number and area burned between the periods 1980–1994 and 1995–2009. Despite this decrease, losses and fatalities from wildfires continue. This suggests that localized areas and seasons of high wildfire risk persist on the island. Our analysis showed (1) a reduction in area burned (60,000–20,000 ha/year) and ignitions (3,700–2,600 fires/year), (2) an advance of 15 days for the fire season peak, (3) an increase in spring temperatures, and (4) an increase in fire exposure for WUI areas. Little change was noted for land use types and associated fuels. Most likely the reduction in fire activity may be due to a combination of social factors and suppression capabilities. On the other hand, simulation modeling suggested pockets of high wildfire exposure in specific places. The combined empirical analyses and simulation modeling provided a robust approach to understanding the spatiotemporal dynamics of wildfire risk on the island.
► We used simulation modeling to analyze spatial patterns in wildfire risk factors. ► The study area encompassed a fire-prone national forest in the western US. ► Variation in risk was observed among ...conservation reserves and urban interfaces. ► Wildfire source–sink relationships were also examined. ► The results can be used to prioritize risk mitigation activities.
We used simulation modeling to analyze wildfire exposure to social and ecological values on a 0.6millionha national forest in central Oregon, USA. We simulated 50,000 wildfires that replicated recent fire events in the area and generated detailed maps of burn probability (BP) and fire intensity distributions. We also recorded the ignition locations and size of each simulated fire and used these outputs to construct a fire source–sink ratio as the ratio of fire size to burn probability. Fire behavior was summarized for federal land management designations, including biological conservation reserves, recreational sites, managed forest, and wildland urban interface. Burn probability from the simulations ranged from 0.00001 to 0.026 within the study area (mean=0.0023), and exhibited substantial variation among and within land designations. Simulated fire behavior was broadly related to gradients in fire regimes, although the combined effects of fuel, topography, and simulated weather resulted in fine scale patterns not reflected in ecological and vegetation data. Average BP for the northern spotted owl (Strix occidentalis caurina) nesting sites ranged from 0.0002 to 0.04. Among the 130 different wildland urban interface areas, average BP varied from 0.0001 to 0.02. Spatial variation in the source–sink ratio was pronounced, and strongly affected by the continuity and arrangement of surface and canopy fuel. We discuss the management implications in terms of prioritizing fuel management activities and designing conservation strategies on fire prone landscapes within the 177millionha national forest network.
Managing forests has been demonstrated to be an efficient strategy for fragmenting fuels and for reducing fire spread rates and severity. However, large-scale analyses to examine operational aspects ...of implementing different forest management scenarios to meet fire governance objectives are nonexistent for many Mediterranean countries. In this study we described an optimization framework to build forest management scenarios that leverages fire simulation, forest management, and tradeoff analyses for forest areas in Macedonia, Greece. We demonstrated the framework to evaluate five forest management priorities aimed at (1) protection of developed areas, (2) optimized commercial timber harvests, (3) protection of ecosystem services, (4) fire resilience, and (5) reducing suppression difficulty. Results revealed that by managing approximately 33,000 ha across all lands in different allocations of 100 projects, the area that accounted for 16% of the wildfire exposure to developed areas was treated while harvesting 2.5% of total wood volume. The treatments also reduced fuels on the area that are responsible for 3% of the potential fire impacts to sites with important ecosystem services, while suppression difficulty and wildfire transmission to protected areas attainment was 4.5% and 16%, respectively. We also tested the performance of multiple forest district management priorities when applying a proposed four-year fuel treatment plan that targeted achieving high levels of attainment by treating less area but strategically selected lands. Sharp management tradeoffs were observed among all management priorities, especially for harvest production compared with suppression difficulty, the protection of developed areas, and wildfire exposure to protected areas.
PDF
