Jonathan Long | American River College (original) (raw)
Papers by Jonathan Long
Ecology and Society, 2022
Across the United States, wildfire severity and frequency are increasing, placing many properties... more Across the United States, wildfire severity and frequency are increasing, placing many properties at risk of harm or destruction. We quantify and compare how different forest management strategies designed to increase forest resilience and health reduce the number of properties at risk from wildfire, focusing on the Lake Tahoe Basin of California and Nevada. We combine landscape change simulations (including climate change, wildfire, and management effects) with scenarios of current and plausible fuel treatment activities and parcel-scale fire risk analysis. Results suggest that more aggressive fuel treatment activities that treat more area on the landscape, whether through mechanical and hand thinning or prescribed fire, dramatically lower the fire probability in the region and lead to a corresponding lower risk of property loss. We estimate that relative to recent practices of focusing management in the wildland-urban interface, more active forest management can reduce property loss risk by 45%-76%, or approximately 2600-4900 properties. The majority of this risk reduction is for single family residences, which constitute most structures in the region. Further, we find that the highest risk reduction is obtained through strategies that treat a substantially greater area than is currently treated in the region and allows for selective wildfires to burn for resource objectives outside of the wildland-urban interface. These results highlight the importance of more active forest management as an effective tool in reducing the wildfire risk to capital assets in the region.
Water and aquatic ecosystems in the synthesis area have high social, cultural, and ecological val... more Water and aquatic ecosystems in the synthesis area have high social, cultural, and ecological values. National forests in the synthesis area are a major source of water supply, hydropower, and recreational activity for much of California. Recent research has provided more information on water and nutrient budgets; these data are fundamental to understanding the interaction of terrestrial and aquatic ecosystems, current forest conditions, and response to stressors. Rapid changes in climate pose a threat to water resources, as warming has produced a shift toward more precipitation falling as rain than snow, which reduces snowpack water storage, causes earlier runoff, increases the frequency of major floods through rain-on-snow events, and diminishes late-season flows and the stability of headwater habitats. Because climate change is expected to increase impacts from storms and wildfires, flooding and sediment movement may increase, which could in turn reduce channel stability and habitat quality. Hydrologic response to climate change is expected to be different for the northern, central, and southern Sierra Nevada. Recent research has noted that natural disturbances such as fires and floods and associated erosion can be important for maintaining stream functions and biodiversity; however, systems that are already degraded or have limited connectivity for aquatic life may be vulnerable to losses following disturbances. Significant increases in sedimentation rates may negatively affect sensitive aquatic organisms and reservoirs. Therefore, efforts to promote a fire regime that results in fewer uncharacteristically large and severe wildfires can help maintain resilience of aquatic systems. Forest restoration treatments may promote resilience to drought, wildfire, insects, and disease, and they could increase water available to soils, groundwater, and streams owing to reduced transpiration and increased snowpack. However, forest treatments that are not designed primarily to increase water yield may not remove sufficient trees to result in an easily measured and sustained increase in water. Consequently, evaluations of the water benefits of general restoration treatments will depend on the combination of long-term experimental studies and modeling, which have been initiated in the past decade. Aquatic systems that have not
Rangeland Ecology & Management, Jul 1, 2006
The geologic diversity of landforms in the Southwest complicates efforts to evaluate impacts of l... more The geologic diversity of landforms in the Southwest complicates efforts to evaluate impacts of land uses such as livestock grazing. We examined a research study that evaluated relationships between trout biomass and stream habitat in the White Mountains of east-central Arizona. That study interpreted results of stepwise regressions and a nonparametric test of ''grazed and ungrazed meadow reaches'' as evidence that livestock grazing was the most important factor to consider in the recovery of the Apache trout (Oncorhynchus apache Miller). That study had assumed that geologic variation was insignificant in the study area. However, lithologic and topographic differences between the felsic slopes of Mount Baldy and adjacent mafic plateaus influence many attributes of trout habitat. We tested the robustness of the earlier study by using its dataset and its method of stepwise regression, but with the addition of a variable representing geologic variation. The results suggested that geology was a highly significant predictor of trout biomass (P , 0.0001), whereas bank damage by ungulates was not a useful predictor of residual variation in trout biomass after accounting for geology (r 2 ¼ 0.015, P ¼ 0.290). However, the associations between natural variation and land use impacts in this spatial dataset confound attempts to make inferences concerning effects of livestock grazing upon trout. Despite fundamental problems in the analysis, the results of the earlier study were repeatedly cited in scientific literature and debates about grazing management. To fairly decipher relationships between ecological production and livestock grazing in diverse landscapes requires temporal studies with reliable methodologies and proper controls for landscape variation. Ignoring geologic variation has the potential to mislead conservation policies by inappropriately implicating land use, by undervaluing inherently favorable habitats, and by inflating expectations for inherently less favorable habitats. La diversidad geolo ´gica de los paisajes del Sudoeste Americano complica los esfuerzos para evaluar los impactos de los usos del suelo, como el apacentamiento del ganado. Examinamos una investigacio ´n que evaluo ´las relaciones entre la biomasa de truchas y su ha ´bitat riberen ˜o en las White Mountains, de la region este-central de Arizona. Ese estudio interpreto ´resultados de regresio ´n gradual y una prueba no parame ´trica de ''praderas apacentadas y no apacentadas,'' como evidencia de que el apacentamiento del ganado era el factor ma ´s importante a considerar en la recuperacio ´n de la trucha ''Apache'' (Oncorhynchus apache Miller). Ese estudio habı ´a asumido que la variacio ´n geolo ´gica era insignificante en el a ´rea del estudio. Sin embargo, las diferencias litolo ´gicas y topogra ´ficas entre las pendientes fe ´lsicas del Mount Baldy y las mesetas ma ´ficas adyacentes influencian muchos atributos del ha ´bitat de la trucha. Probamos la robustez del estudio anterior usando sus datos y su me ´todo de regresio ´n gradual, pero con la adicio ´n de una variable representando la variacio ´n geolo ´gica. Los resultados sugirieron que la geologı ´a fue un predictor altamente significativo de la biomasa de la trucha (P , 0.0001), mientras que el dan ˜o de las riberas por los ungulados no fue un predictor u ´til de la variacio ´n residual en biomasa de la trucha despue ´s de considerar la geologı ´a (r 2 ¼ 0.015, P ¼ 0.290). Sin embargo, las asociaciones entre variacio ´n natural y la utilizacio ´n del suelo en este juego espacial de datos confunden los intentos de hacer inferencias respecto a los efectos del apacentamineto del ganado sobre la trucha. A pesar de problemas fundamentales en el ana ´lisis, los resultados del estudio previo fueron citados repetidamente en la literatura y discusiones cientı ´ficas sobre el manejo del apacentamineto. Para descifrar justamente las relaciones entre la produccio ´n ecolo ´gica y el apacentamineto del ganado en paisajes diversos, tambie ´n se requieren estudios temporales con metodologı ´as confiables y controles apropiados de la variacio ´n del paisaje. Ignorar la variacio ´n geolo ´gica tiene el potencial de conduccir erroneamente las politicas de conservacio ´n al implicar inapropiadamente la utilizacio ´n del suelo, por subvaluar los ha ´bitats intrı ´nsecamente favorables, y por sobrevalorar las espectativas para ha ´bitats intrı ´nsecamente menos favorables.
Ecology and Society, 2022
Climate change will accelerate forest mortality due to insects, disease, and wildfire. As a resul... more Climate change will accelerate forest mortality due to insects, disease, and wildfire. As a result, substantial resources will be necessary where and when forest managers seek to maintain multiple management objectives. Because of the increasing managerial requirements to offset climate change and related disturbances, the uncertainty about future forest conditions is magnified relative to climate change alone. We provide an analytical approach that quantifies the key drivers of forest change-climate, disturbance, and forest management-using scenarios paired with simulation modeling to forecast and quantify uncertainties in the Lake Tahoe Basin of California and Nevada (USA), a montane seasonally dry conifer forest. We partitioned uncertainty among climate change (including associated changes to wildfire and insect outbreaks), forest management (including thinning, prescribed fire, and fire suppression), and other sources using a fully factorial experimental design and analysis of variance. We focused on three metrics that are important for forest management objectives for the area: forest carbon storage, area burned at high severity, and total area burned by wildfire. Management explained a substantial amount of variance in the short term for area burned at high severity and longer term carbon storage, while climate explained the most variance in total area burned. Our results suggest that simulated extensive management activities will not meet all the desired management objectives. Both the extent and intensity of forest management will need to increase significantly to keep pace with predicted climate and wildfire conditions.
Riparian areas are typically highly productive areas that sustain important socioecological benef... more Riparian areas are typically highly productive areas that sustain important socioecological benefits, including the capacity to modulate effects of watershed disturbances on aquatic systems. Recent studies have shown that fire behavior in riparian areas varies with landscape attributes. Smaller, headwater riparian areas often burn similarly to adjacent uplands, whereas riparian areas next to larger streams (4 th order and higher) often burn less frequently and less severely because of moister microclimates, and therefore can serve as fire breaks within a landscape. However, other riparian areas may accumulate fuels rapidly owing to their high productivity, and during dry fire seasons they can serve as wicks that carry high-intensity fire through a landscape. These localized relationships with fire suggest that treatment strategies for riparian areas should be customized and likely would differ. However, riparian areas that are vulnerable to uncharacteristically high-severity fire may benefit from being included in upland treatments to render them and their associated landscapes more resilient to wildfire. Furthermore, treatments that reduce tree density and increase light may have positive effects on understory plant diversity and aquatic productivity in some riparian areas, including those with aspen. Studies on prescribed fire in Sierra Nevada riparian areas have found relatively benign impacts. However, information about the effects of both mechanical treatments and fire treatments is still relatively limited, which suggests a need for experimental treatments. Overall, an adaptive management strategy based upon active management within some riparian areas may promote resilience better than a broad handsoff approach.
Journal of Forestry
Hardwoods resprouting after wildfire or cutting develop as multistemmed clumps that gradually sel... more Hardwoods resprouting after wildfire or cutting develop as multistemmed clumps that gradually self-thin over time. There is increasing interest in thinning of sprouting species to accelerate the formation of tree characteristics important to indigenous cultural practices and wildlife such as large-diameter stems, large branches, broad crowns, and acorn production. We compared responses to three thinning treatments applied to black oak (Quercus kelloggii) resprouting after high-severity wildfire throughout northern California, USA. Basal area increment of the dominant stem was greatest after only one stem was retained, intermediate after three stems were retained, and lowest within unthinned oaks. Unwanted resprouting in response to the thinning was minimized by retaining three stems. Acorn production tended to increase as time elapsed since the fire (i.e., larger, older sprouts) but varied among sites and was noted as early as six years after fire at one site. More study is needed t...
Long-term monitoring programs and research related to Northwest Forest Plan (NWFP, or Plan) goals... more Long-term monitoring programs and research related to Northwest Forest Plan (NWFP, or Plan) goals, strategies, and outcomes provide an unprecedented opportunity to examine how the scientific basis and socioecological context of the Plan may have changed during the 23 years since its implementation. We also have a prime opportunity to reassess how well the goals and strategies of the Plan are positioned to address new issues.
In this chapter, we review scientific information regarding the conservation and restoration of f... more In this chapter, we review scientific information regarding the conservation and restoration of forest ecosystems on public lands within the Northwest Forest Plan (NWFP, or Plan) area that harbor special value for American Indian tribes and individuals. We highlight advances in understanding how changes in climate, fire, hydrology, vegetation, and resource management regimes have affected tribal ecocultural resources and how land management can promote ecocultural resources in the future. In particular, we examine how distinctive strategies for engaging tribes in restoring ecocultural resources can uphold both tribal rights and federal responsibilities, while supporting other federal land management goals.
Ecology and Society
Land managers in the Lake Tahoe basin are considering increasing the use of prescribed fire and f... more Land managers in the Lake Tahoe basin are considering increasing the use of prescribed fire and forest thinning to restore conditions that will be more resilient to wildfires. However, such restorative treatments also constitute disturbances that could increase sediment and nutrient loads. We examined whether the water-quality impacts from future treatments are likely to be lower compared to the potential impacts from future wildfires under various climate change scenarios. We applied an online interface for the Water Erosion Prediction Project (WEPP) model in combination with a landscape change model (LANDIS-II) to evaluate the effects of different combinations of thinning and prescribed burning on fine sediment (< 2 mm), very fine sediment (< 16 µm), and phosphorus over time. First, we generated results based on historic weather data for soil disturbance conditions, including: an undisturbed baseline, a uniform thinning treatment; a uniform prescribed fire treatment; and uniform low, moderate, and high wildfire burn severity. Residual ground cover declined in that order, and expected loads of sediment and phosphorus increased. We then combined the estimated loads from hillslopes with projected management-disturbance regimes across each decade of the next century. We found that expected sediment and phosphorus loads were lower under the scenario that emphasized thinning, whereas scenarios that increased prescribed burning resulted in loads that were comparable to scenarios that involved less treatment. These results reflect the finding from the WEPP analysis that prescribed burning is expected to reduce ground cover more than is thinning. Our analysis supports efforts to increase fuel reduction treatments to mitigate future wildfires, but it also suggests that preventative treatments may not avoid a long-term decline in water quality as wildfires increase with climate change.
Ecology and Society, 2022
The 1994 Northwest Forest Plan (NWFP) was developed to resolve debates over old-growth forests, e... more The 1994 Northwest Forest Plan (NWFP) was developed to resolve debates over old-growth forests, endangered species, and timber production on federal forests in the range of the northern spotted owl. This three-volume science synthesis, which consists of 12 chapters that address various ecological and social concerns, is intended to inform forest plan revision and forest management within the NWFP area. Land managers with the U.S. Forest Service provided questions that helped guide preparation of the synthesis, which builds on the 10-, 15-, and 20-year NWFP monitoring reports and synthesizes the vast body of relevant scientific literature that has accumulated in the 24 years since the NWFP was initiated. It identifies scientific findings, lessons learned, and uncertainties and also evaluates competing science and provides considerations for management. This synthesis finds that the NWFP has protected dense old-growth forests and maintained habitat for northern spotted owls, marbled m...
ABSTRACT. A complex geologic history has shaped the distribution of Arizona willow (Salix arizoni... more ABSTRACT. A complex geologic history has shaped the distribution of Arizona willow (Salix arizonica Dorn) and the Mogollon paintbrush (Castilleja mogollonica Pennell). These subalpine plants do not appear to be strict substrate specialists, but they do seem to favor coarse-textured and well-watered soils. Most of their occupied habitats were shaped by Quaternary glaciations, but are ultimately derived from felsic substrates formed before the Pliocene period. Populations of Arizona willow have been identified in the White Mountains of Arizona, the High Plateaus of Utah, and in the Southern Rocky Mountains of New Mexico and Colorado. Species closely related to the Mogollon paintbrush also occur in the Utah plateaus and the Southern Rocky Mountains. Genetic dissimilarity among these populations suggest that these taxa likely share an evolutionary history that extends into the Neogene, when tributaries of the ancestral Colorado River connected young volcanic highlands on the margins of ...
Streamside environments are inherently dynamic, yet streamside vegetation plays a key stabilizing... more Streamside environments are inherently dynamic, yet streamside vegetation plays a key stabilizing role on riparian and aquatic habitats (Van Devender and Spaulding 1979; Van Devender and others 1987). Because of its dynamism, streamside vegetation is rarely the subject of classification analyses, yet it is a focal point for land managers regulating land uses, such as livestock grazing, that could potentially impact aquatic communities (Brown and others 1979). Livestock grazing along the UVR has been a politically charged issue, with recent years (1998 to present) witnessing a removal of livestock from the river corridor under Prescott National Forest management. However, livestock still graze on private lands, with some strays roaming onto State and Forest lands (see Chapter 2). During the same period, researchers observed declining populations of native fishes in the UVR, largely attributable to predation by introduced fishes (see Chapter 9), as well as to vast growth of woody plan...
Sociocultural perspectives on threats, risks, and health are explored in this chapter. The author... more Sociocultural perspectives on threats, risks, and health are explored in this chapter. The authors begin with a discussion of the linkages between well-being in the Sierra Nevada ecosystem and public health and well-being to set the context of socioecological resilience. This is followed by a summary of how trust and confidence influence the management of threats and risk. Selected ecosystem dynamics and threats of specific concern in this synthesis are discussed, and include climate change, wildland fire, and invasive species. The chapter closes with a discussion of research findings on decisionmaking related to threats and risk.
This chapter sets the context for the following sociocultural sections of the synthesis by provid... more This chapter sets the context for the following sociocultural sections of the synthesis by providing information on the broader social, cultural, and economic patterns in the Sierra Nevada and southern Cascade Range. Demographic influences surrounding population change, including those accounted for through amenity migration, are examined. Social and cultural concerns surrounding place meanings and place attachments are reviewed next, including potential influences on responses to natural resource management. Managing for resilience includes effectively applying a “triple bottom line approach,” presented in this chapter through a discussion of recreation and tourism, one of the ecosystem services of importance in the assessment region.
Ecology and Society, 2022
Across the United States, wildfire severity and frequency are increasing, placing many properties... more Across the United States, wildfire severity and frequency are increasing, placing many properties at risk of harm or destruction. We quantify and compare how different forest management strategies designed to increase forest resilience and health reduce the number of properties at risk from wildfire, focusing on the Lake Tahoe Basin of California and Nevada. We combine landscape change simulations (including climate change, wildfire, and management effects) with scenarios of current and plausible fuel treatment activities and parcel-scale fire risk analysis. Results suggest that more aggressive fuel treatment activities that treat more area on the landscape, whether through mechanical and hand thinning or prescribed fire, dramatically lower the fire probability in the region and lead to a corresponding lower risk of property loss. We estimate that relative to recent practices of focusing management in the wildland-urban interface, more active forest management can reduce property loss risk by 45%-76%, or approximately 2600-4900 properties. The majority of this risk reduction is for single family residences, which constitute most structures in the region. Further, we find that the highest risk reduction is obtained through strategies that treat a substantially greater area than is currently treated in the region and allows for selective wildfires to burn for resource objectives outside of the wildland-urban interface. These results highlight the importance of more active forest management as an effective tool in reducing the wildfire risk to capital assets in the region.
Water and aquatic ecosystems in the synthesis area have high social, cultural, and ecological val... more Water and aquatic ecosystems in the synthesis area have high social, cultural, and ecological values. National forests in the synthesis area are a major source of water supply, hydropower, and recreational activity for much of California. Recent research has provided more information on water and nutrient budgets; these data are fundamental to understanding the interaction of terrestrial and aquatic ecosystems, current forest conditions, and response to stressors. Rapid changes in climate pose a threat to water resources, as warming has produced a shift toward more precipitation falling as rain than snow, which reduces snowpack water storage, causes earlier runoff, increases the frequency of major floods through rain-on-snow events, and diminishes late-season flows and the stability of headwater habitats. Because climate change is expected to increase impacts from storms and wildfires, flooding and sediment movement may increase, which could in turn reduce channel stability and habitat quality. Hydrologic response to climate change is expected to be different for the northern, central, and southern Sierra Nevada. Recent research has noted that natural disturbances such as fires and floods and associated erosion can be important for maintaining stream functions and biodiversity; however, systems that are already degraded or have limited connectivity for aquatic life may be vulnerable to losses following disturbances. Significant increases in sedimentation rates may negatively affect sensitive aquatic organisms and reservoirs. Therefore, efforts to promote a fire regime that results in fewer uncharacteristically large and severe wildfires can help maintain resilience of aquatic systems. Forest restoration treatments may promote resilience to drought, wildfire, insects, and disease, and they could increase water available to soils, groundwater, and streams owing to reduced transpiration and increased snowpack. However, forest treatments that are not designed primarily to increase water yield may not remove sufficient trees to result in an easily measured and sustained increase in water. Consequently, evaluations of the water benefits of general restoration treatments will depend on the combination of long-term experimental studies and modeling, which have been initiated in the past decade. Aquatic systems that have not
Rangeland Ecology & Management, Jul 1, 2006
The geologic diversity of landforms in the Southwest complicates efforts to evaluate impacts of l... more The geologic diversity of landforms in the Southwest complicates efforts to evaluate impacts of land uses such as livestock grazing. We examined a research study that evaluated relationships between trout biomass and stream habitat in the White Mountains of east-central Arizona. That study interpreted results of stepwise regressions and a nonparametric test of ''grazed and ungrazed meadow reaches'' as evidence that livestock grazing was the most important factor to consider in the recovery of the Apache trout (Oncorhynchus apache Miller). That study had assumed that geologic variation was insignificant in the study area. However, lithologic and topographic differences between the felsic slopes of Mount Baldy and adjacent mafic plateaus influence many attributes of trout habitat. We tested the robustness of the earlier study by using its dataset and its method of stepwise regression, but with the addition of a variable representing geologic variation. The results suggested that geology was a highly significant predictor of trout biomass (P , 0.0001), whereas bank damage by ungulates was not a useful predictor of residual variation in trout biomass after accounting for geology (r 2 ¼ 0.015, P ¼ 0.290). However, the associations between natural variation and land use impacts in this spatial dataset confound attempts to make inferences concerning effects of livestock grazing upon trout. Despite fundamental problems in the analysis, the results of the earlier study were repeatedly cited in scientific literature and debates about grazing management. To fairly decipher relationships between ecological production and livestock grazing in diverse landscapes requires temporal studies with reliable methodologies and proper controls for landscape variation. Ignoring geologic variation has the potential to mislead conservation policies by inappropriately implicating land use, by undervaluing inherently favorable habitats, and by inflating expectations for inherently less favorable habitats. La diversidad geolo ´gica de los paisajes del Sudoeste Americano complica los esfuerzos para evaluar los impactos de los usos del suelo, como el apacentamiento del ganado. Examinamos una investigacio ´n que evaluo ´las relaciones entre la biomasa de truchas y su ha ´bitat riberen ˜o en las White Mountains, de la region este-central de Arizona. Ese estudio interpreto ´resultados de regresio ´n gradual y una prueba no parame ´trica de ''praderas apacentadas y no apacentadas,'' como evidencia de que el apacentamiento del ganado era el factor ma ´s importante a considerar en la recuperacio ´n de la trucha ''Apache'' (Oncorhynchus apache Miller). Ese estudio habı ´a asumido que la variacio ´n geolo ´gica era insignificante en el a ´rea del estudio. Sin embargo, las diferencias litolo ´gicas y topogra ´ficas entre las pendientes fe ´lsicas del Mount Baldy y las mesetas ma ´ficas adyacentes influencian muchos atributos del ha ´bitat de la trucha. Probamos la robustez del estudio anterior usando sus datos y su me ´todo de regresio ´n gradual, pero con la adicio ´n de una variable representando la variacio ´n geolo ´gica. Los resultados sugirieron que la geologı ´a fue un predictor altamente significativo de la biomasa de la trucha (P , 0.0001), mientras que el dan ˜o de las riberas por los ungulados no fue un predictor u ´til de la variacio ´n residual en biomasa de la trucha despue ´s de considerar la geologı ´a (r 2 ¼ 0.015, P ¼ 0.290). Sin embargo, las asociaciones entre variacio ´n natural y la utilizacio ´n del suelo en este juego espacial de datos confunden los intentos de hacer inferencias respecto a los efectos del apacentamineto del ganado sobre la trucha. A pesar de problemas fundamentales en el ana ´lisis, los resultados del estudio previo fueron citados repetidamente en la literatura y discusiones cientı ´ficas sobre el manejo del apacentamineto. Para descifrar justamente las relaciones entre la produccio ´n ecolo ´gica y el apacentamineto del ganado en paisajes diversos, tambie ´n se requieren estudios temporales con metodologı ´as confiables y controles apropiados de la variacio ´n del paisaje. Ignorar la variacio ´n geolo ´gica tiene el potencial de conduccir erroneamente las politicas de conservacio ´n al implicar inapropiadamente la utilizacio ´n del suelo, por subvaluar los ha ´bitats intrı ´nsecamente favorables, y por sobrevalorar las espectativas para ha ´bitats intrı ´nsecamente menos favorables.
Ecology and Society, 2022
Climate change will accelerate forest mortality due to insects, disease, and wildfire. As a resul... more Climate change will accelerate forest mortality due to insects, disease, and wildfire. As a result, substantial resources will be necessary where and when forest managers seek to maintain multiple management objectives. Because of the increasing managerial requirements to offset climate change and related disturbances, the uncertainty about future forest conditions is magnified relative to climate change alone. We provide an analytical approach that quantifies the key drivers of forest change-climate, disturbance, and forest management-using scenarios paired with simulation modeling to forecast and quantify uncertainties in the Lake Tahoe Basin of California and Nevada (USA), a montane seasonally dry conifer forest. We partitioned uncertainty among climate change (including associated changes to wildfire and insect outbreaks), forest management (including thinning, prescribed fire, and fire suppression), and other sources using a fully factorial experimental design and analysis of variance. We focused on three metrics that are important for forest management objectives for the area: forest carbon storage, area burned at high severity, and total area burned by wildfire. Management explained a substantial amount of variance in the short term for area burned at high severity and longer term carbon storage, while climate explained the most variance in total area burned. Our results suggest that simulated extensive management activities will not meet all the desired management objectives. Both the extent and intensity of forest management will need to increase significantly to keep pace with predicted climate and wildfire conditions.
Riparian areas are typically highly productive areas that sustain important socioecological benef... more Riparian areas are typically highly productive areas that sustain important socioecological benefits, including the capacity to modulate effects of watershed disturbances on aquatic systems. Recent studies have shown that fire behavior in riparian areas varies with landscape attributes. Smaller, headwater riparian areas often burn similarly to adjacent uplands, whereas riparian areas next to larger streams (4 th order and higher) often burn less frequently and less severely because of moister microclimates, and therefore can serve as fire breaks within a landscape. However, other riparian areas may accumulate fuels rapidly owing to their high productivity, and during dry fire seasons they can serve as wicks that carry high-intensity fire through a landscape. These localized relationships with fire suggest that treatment strategies for riparian areas should be customized and likely would differ. However, riparian areas that are vulnerable to uncharacteristically high-severity fire may benefit from being included in upland treatments to render them and their associated landscapes more resilient to wildfire. Furthermore, treatments that reduce tree density and increase light may have positive effects on understory plant diversity and aquatic productivity in some riparian areas, including those with aspen. Studies on prescribed fire in Sierra Nevada riparian areas have found relatively benign impacts. However, information about the effects of both mechanical treatments and fire treatments is still relatively limited, which suggests a need for experimental treatments. Overall, an adaptive management strategy based upon active management within some riparian areas may promote resilience better than a broad handsoff approach.
Journal of Forestry
Hardwoods resprouting after wildfire or cutting develop as multistemmed clumps that gradually sel... more Hardwoods resprouting after wildfire or cutting develop as multistemmed clumps that gradually self-thin over time. There is increasing interest in thinning of sprouting species to accelerate the formation of tree characteristics important to indigenous cultural practices and wildlife such as large-diameter stems, large branches, broad crowns, and acorn production. We compared responses to three thinning treatments applied to black oak (Quercus kelloggii) resprouting after high-severity wildfire throughout northern California, USA. Basal area increment of the dominant stem was greatest after only one stem was retained, intermediate after three stems were retained, and lowest within unthinned oaks. Unwanted resprouting in response to the thinning was minimized by retaining three stems. Acorn production tended to increase as time elapsed since the fire (i.e., larger, older sprouts) but varied among sites and was noted as early as six years after fire at one site. More study is needed t...
Long-term monitoring programs and research related to Northwest Forest Plan (NWFP, or Plan) goals... more Long-term monitoring programs and research related to Northwest Forest Plan (NWFP, or Plan) goals, strategies, and outcomes provide an unprecedented opportunity to examine how the scientific basis and socioecological context of the Plan may have changed during the 23 years since its implementation. We also have a prime opportunity to reassess how well the goals and strategies of the Plan are positioned to address new issues.
In this chapter, we review scientific information regarding the conservation and restoration of f... more In this chapter, we review scientific information regarding the conservation and restoration of forest ecosystems on public lands within the Northwest Forest Plan (NWFP, or Plan) area that harbor special value for American Indian tribes and individuals. We highlight advances in understanding how changes in climate, fire, hydrology, vegetation, and resource management regimes have affected tribal ecocultural resources and how land management can promote ecocultural resources in the future. In particular, we examine how distinctive strategies for engaging tribes in restoring ecocultural resources can uphold both tribal rights and federal responsibilities, while supporting other federal land management goals.
Ecology and Society
Land managers in the Lake Tahoe basin are considering increasing the use of prescribed fire and f... more Land managers in the Lake Tahoe basin are considering increasing the use of prescribed fire and forest thinning to restore conditions that will be more resilient to wildfires. However, such restorative treatments also constitute disturbances that could increase sediment and nutrient loads. We examined whether the water-quality impacts from future treatments are likely to be lower compared to the potential impacts from future wildfires under various climate change scenarios. We applied an online interface for the Water Erosion Prediction Project (WEPP) model in combination with a landscape change model (LANDIS-II) to evaluate the effects of different combinations of thinning and prescribed burning on fine sediment (< 2 mm), very fine sediment (< 16 µm), and phosphorus over time. First, we generated results based on historic weather data for soil disturbance conditions, including: an undisturbed baseline, a uniform thinning treatment; a uniform prescribed fire treatment; and uniform low, moderate, and high wildfire burn severity. Residual ground cover declined in that order, and expected loads of sediment and phosphorus increased. We then combined the estimated loads from hillslopes with projected management-disturbance regimes across each decade of the next century. We found that expected sediment and phosphorus loads were lower under the scenario that emphasized thinning, whereas scenarios that increased prescribed burning resulted in loads that were comparable to scenarios that involved less treatment. These results reflect the finding from the WEPP analysis that prescribed burning is expected to reduce ground cover more than is thinning. Our analysis supports efforts to increase fuel reduction treatments to mitigate future wildfires, but it also suggests that preventative treatments may not avoid a long-term decline in water quality as wildfires increase with climate change.
Ecology and Society, 2022
The 1994 Northwest Forest Plan (NWFP) was developed to resolve debates over old-growth forests, e... more The 1994 Northwest Forest Plan (NWFP) was developed to resolve debates over old-growth forests, endangered species, and timber production on federal forests in the range of the northern spotted owl. This three-volume science synthesis, which consists of 12 chapters that address various ecological and social concerns, is intended to inform forest plan revision and forest management within the NWFP area. Land managers with the U.S. Forest Service provided questions that helped guide preparation of the synthesis, which builds on the 10-, 15-, and 20-year NWFP monitoring reports and synthesizes the vast body of relevant scientific literature that has accumulated in the 24 years since the NWFP was initiated. It identifies scientific findings, lessons learned, and uncertainties and also evaluates competing science and provides considerations for management. This synthesis finds that the NWFP has protected dense old-growth forests and maintained habitat for northern spotted owls, marbled m...
ABSTRACT. A complex geologic history has shaped the distribution of Arizona willow (Salix arizoni... more ABSTRACT. A complex geologic history has shaped the distribution of Arizona willow (Salix arizonica Dorn) and the Mogollon paintbrush (Castilleja mogollonica Pennell). These subalpine plants do not appear to be strict substrate specialists, but they do seem to favor coarse-textured and well-watered soils. Most of their occupied habitats were shaped by Quaternary glaciations, but are ultimately derived from felsic substrates formed before the Pliocene period. Populations of Arizona willow have been identified in the White Mountains of Arizona, the High Plateaus of Utah, and in the Southern Rocky Mountains of New Mexico and Colorado. Species closely related to the Mogollon paintbrush also occur in the Utah plateaus and the Southern Rocky Mountains. Genetic dissimilarity among these populations suggest that these taxa likely share an evolutionary history that extends into the Neogene, when tributaries of the ancestral Colorado River connected young volcanic highlands on the margins of ...
Streamside environments are inherently dynamic, yet streamside vegetation plays a key stabilizing... more Streamside environments are inherently dynamic, yet streamside vegetation plays a key stabilizing role on riparian and aquatic habitats (Van Devender and Spaulding 1979; Van Devender and others 1987). Because of its dynamism, streamside vegetation is rarely the subject of classification analyses, yet it is a focal point for land managers regulating land uses, such as livestock grazing, that could potentially impact aquatic communities (Brown and others 1979). Livestock grazing along the UVR has been a politically charged issue, with recent years (1998 to present) witnessing a removal of livestock from the river corridor under Prescott National Forest management. However, livestock still graze on private lands, with some strays roaming onto State and Forest lands (see Chapter 2). During the same period, researchers observed declining populations of native fishes in the UVR, largely attributable to predation by introduced fishes (see Chapter 9), as well as to vast growth of woody plan...
Sociocultural perspectives on threats, risks, and health are explored in this chapter. The author... more Sociocultural perspectives on threats, risks, and health are explored in this chapter. The authors begin with a discussion of the linkages between well-being in the Sierra Nevada ecosystem and public health and well-being to set the context of socioecological resilience. This is followed by a summary of how trust and confidence influence the management of threats and risk. Selected ecosystem dynamics and threats of specific concern in this synthesis are discussed, and include climate change, wildland fire, and invasive species. The chapter closes with a discussion of research findings on decisionmaking related to threats and risk.
This chapter sets the context for the following sociocultural sections of the synthesis by provid... more This chapter sets the context for the following sociocultural sections of the synthesis by providing information on the broader social, cultural, and economic patterns in the Sierra Nevada and southern Cascade Range. Demographic influences surrounding population change, including those accounted for through amenity migration, are examined. Social and cultural concerns surrounding place meanings and place attachments are reviewed next, including potential influences on responses to natural resource management. Managing for resilience includes effectively applying a “triple bottom line approach,” presented in this chapter through a discussion of recreation and tourism, one of the ecosystem services of importance in the assessment region.