... Add a tag: No tags have been applied to this document. BibTeX | Add To MetaCart. @MISC{Sieg99... more ... Add a tag: No tags have been applied to this document. BibTeX | Add To MetaCart. @MISC{Sieg99recentbiodiversity, author = {Carolyn Hull Sieg and Curtis H ... Pages 8-18 Anderson - 1990. 11, Economic and environmental benefits of biodiversity Pimentel, Wilson, et al. - 1997 ...
Ecosystem, species and genetic dimensions of biodiversity have eroded since widespread settlement... more Ecosystem, species and genetic dimensions of biodiversity have eroded since widespread settlement of the Great Plains. Conversion of native vegetation in the region followed the precipitation gradient, with the greatest conversion in the eastern tallgrass prairie and eastern mixed-grass types. Areas now dominated by intensive land uses are "hot spots" for exotic birds. However, species of all taxa listed as
Phnt canopy cover, standing crop, and soils were sampled on (I) old (unreclaimed), (2) reclaimed,... more Phnt canopy cover, standing crop, and soils were sampled on (I) old (unreclaimed), (2) reclaimed, (3) semireclaimed (newly mined) bentonite mine spoils and (4) native sagebrush-grass rangelands in southeastern Montana. Plant cover and standing crop were higher on sagebrush-grass rangelands than on all bentonite spoils. Scurf- less saltbush (Atriplex suckleyi) was the most successful and abundant plant on bentonite spoils.
International Journal of Sustainable Development & World Ecology, 2000
... diversity - to rangeland sustainability Curtas H. Flather' and Carolyn H... more ... diversity - to rangeland sustainability Curtas H. Flather' and Carolyn Hull Sac$ ... There is a growing recognition that maintaining this variety is critical to maintaining the goods and services that humans derive from ecosystems (Daily, 1997; Pimentel et aL, 1997). ...
Introduction Landscape-level bark beetle outbreaks have occurred throughout the western US in rec... more Introduction Landscape-level bark beetle outbreaks have occurred throughout the western US in recent decades. FHM aerial detection surveys (ADS) reported >150,000 acres of ponderosa pine impacted by mountain pine beetle in the Black Hills between 2002 and 2008, plus 120,000 acres of Douglas-fir impacted by Douglas-fir beetles in the Shoshone NF and 10,000 acres in the Bighorn NF. Concerns about elevated fire hazard following these outbreaks have led to calls for fuel reduction treatments. The impact of bark beetle outbreaks on stand structure and fuel profiles depends in part on forest type and time-since-outbreak (Jenkins et al. 2008, Hicke et al. 2012). Yet, little information is available for drier forest types and it remains unclear how fuel reduction treatments influence potential fire behavior following a bark beetle outbreak. Our study will provide insights for managing stands impacted from extensive bark beetle outbreaks in South Dakota and Wyoming. Methods • 15 (1/20 th ...
Background/Question/Methods Cheatgrass (Bromus tectorum) is an exotic annual grass that is increa... more Background/Question/Methods Cheatgrass (Bromus tectorum) is an exotic annual grass that is increasingly degrading Southwestern forests and rangelands. It out-competes many native plants and as populations expand, continuous and highly flammable fine fuels develop that further threaten native ecosystems. Land managers are confronted with the challenge of maintaining ecosystem function and resiliency to cheatgrass invasion. In 1996 the Bridger-Knoll fire complex on the north Kaibab Plateau burned through critical mule deer (Odocoileus hemionus) native winter range and a majority of this area is now invaded by cheatgrass. We set up a field experiment to test the effectiveness of applications of Imazapic PLATEAU herbicide to control cheatgrass and seeding to restore native shrubs. The shrubs included Wyoming big sagebrush (Artemisia tridentata) and cliffrose (Purshia mexicana). We also set up experiments at the Rocky Mountain Research Station greenhouse to test the effects of PLATEAU on...
ABSTRACT Patches of live, dead, and dying trees resulting from bark beetle-caused mortality alter... more ABSTRACT Patches of live, dead, and dying trees resulting from bark beetle-caused mortality alter spatial and temporal variability in the canopy and surface fuel complex through changes in the foliar moisture content of attacked trees and through the redistribution of canopy fuels. The resulting heterogeneous fuels complexes alter within-canopy wind flow, wind fluctuations, and rate of fire spread. However, there is currently little information about the potential influence of different rates and patterns of mortality on wind flow and fire behavior following bark beetle outbreaks. In this study, we contrasted within-canopy wind flow and fire rate-of-spread (ROS) at two different ambient wind speeds using FIRETEC for two differing bark beetle attack trajectories for a lodgepole pine (Pinus contorta) forest. These two attack trajectories represent different realizations of a bark beetle outbreak and result in different amounts and patterns of mortality through time. Our simulations suggested that the mean within-canopy wind velocities increased through time following the progression of mortality. In addition, we found that for a given level of mortality, a bark beetle outbreak that resulted in a higher degree of aggregation of canopy fuels had greater mean within-canopy wind velocities due to the channeling of wind flow. These findings suggest that bark beetle mortality can influence the mean within-canopy wind flow in two ways: first, by reducing the amount of vegetation present in the canopy acting as a source of drag; and second, by altering spatial patterns of vegetation that can lead to channeling of wind flow. Changes in the fire rate-of-spread were positively related to the level and continuity of bark beetle mortality. Peak rates of spread were between 1.2 and 2.7 times greater than the pre-outbreak scenario and coincided with a high level of mortality and minimal loss of canopy fuels. Following the loss of canopy fuels the rate of fire spread declined to levels below the initial phases of the outbreak in low wind speed cases but remained above pre-outbreak levels in high wind speed cases. These findings suggest that the rate and pattern of mortality arising from a bark beetle outbreak exerts significant influence on the magnitude and timing of alterations to the within-canopy wind flow and rate of fire spread. Our findings help clarify existing knowledge gaps related to the effect of bark beetle outbreaks on fire behavior and could explain potential differences in the reported effects of bark beetle outbreaks on fire behavior through time.
We evaluate the potential for dcndroclimatological reconstruction in the northern Great Plains of... more We evaluate the potential for dcndroclimatological reconstruction in the northern Great Plains of the United States, based on a newly developed network of 23 chronologies of bur oa k (Quercus macrocarpa), ponderosa pine (Pinus ponderosa) and Rocky Mountain juniper (Juniperus scopoulorum) from North Dakota, South Dakota and Iowa. Earliest dates of specimens are AD 1281 for pine, 1597 for juniper,
Numerous wildfires in recent years have highlighted managers' needs for reliable tools to pre... more Numerous wildfires in recent years have highlighted managers' needs for reliable tools to predict postfire mortality of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) trees. General applicability of existing mortality models is uncertain, as researchers have used different sets of variables. We quantified tree attributes, crown and bole fire damage, ground fire severity, and insect presence from a total of
A single ponderosa pine tree found in the central Black Hills of South Dakota revealed its age of... more A single ponderosa pine tree found in the central Black Hills of South Dakota revealed its age of more than 700 years by its tree rings taken from cor- ing in 1992. The purpose of this study was to examine historic climatic pat- terns from the 13th century through most of the 20th century as inferred from ring widths of
... Add a tag: No tags have been applied to this document. BibTeX | Add To MetaCart. @MISC{Sieg99... more ... Add a tag: No tags have been applied to this document. BibTeX | Add To MetaCart. @MISC{Sieg99recentbiodiversity, author = {Carolyn Hull Sieg and Curtis H ... Pages 8-18 Anderson - 1990. 11, Economic and environmental benefits of biodiversity Pimentel, Wilson, et al. - 1997 ...
Ecosystem, species and genetic dimensions of biodiversity have eroded since widespread settlement... more Ecosystem, species and genetic dimensions of biodiversity have eroded since widespread settlement of the Great Plains. Conversion of native vegetation in the region followed the precipitation gradient, with the greatest conversion in the eastern tallgrass prairie and eastern mixed-grass types. Areas now dominated by intensive land uses are "hot spots" for exotic birds. However, species of all taxa listed as
Phnt canopy cover, standing crop, and soils were sampled on (I) old (unreclaimed), (2) reclaimed,... more Phnt canopy cover, standing crop, and soils were sampled on (I) old (unreclaimed), (2) reclaimed, (3) semireclaimed (newly mined) bentonite mine spoils and (4) native sagebrush-grass rangelands in southeastern Montana. Plant cover and standing crop were higher on sagebrush-grass rangelands than on all bentonite spoils. Scurf- less saltbush (Atriplex suckleyi) was the most successful and abundant plant on bentonite spoils.
International Journal of Sustainable Development & World Ecology, 2000
... diversity - to rangeland sustainability Curtas H. Flather' and Carolyn H... more ... diversity - to rangeland sustainability Curtas H. Flather' and Carolyn Hull Sac$ ... There is a growing recognition that maintaining this variety is critical to maintaining the goods and services that humans derive from ecosystems (Daily, 1997; Pimentel et aL, 1997). ...
Introduction Landscape-level bark beetle outbreaks have occurred throughout the western US in rec... more Introduction Landscape-level bark beetle outbreaks have occurred throughout the western US in recent decades. FHM aerial detection surveys (ADS) reported >150,000 acres of ponderosa pine impacted by mountain pine beetle in the Black Hills between 2002 and 2008, plus 120,000 acres of Douglas-fir impacted by Douglas-fir beetles in the Shoshone NF and 10,000 acres in the Bighorn NF. Concerns about elevated fire hazard following these outbreaks have led to calls for fuel reduction treatments. The impact of bark beetle outbreaks on stand structure and fuel profiles depends in part on forest type and time-since-outbreak (Jenkins et al. 2008, Hicke et al. 2012). Yet, little information is available for drier forest types and it remains unclear how fuel reduction treatments influence potential fire behavior following a bark beetle outbreak. Our study will provide insights for managing stands impacted from extensive bark beetle outbreaks in South Dakota and Wyoming. Methods • 15 (1/20 th ...
Background/Question/Methods Cheatgrass (Bromus tectorum) is an exotic annual grass that is increa... more Background/Question/Methods Cheatgrass (Bromus tectorum) is an exotic annual grass that is increasingly degrading Southwestern forests and rangelands. It out-competes many native plants and as populations expand, continuous and highly flammable fine fuels develop that further threaten native ecosystems. Land managers are confronted with the challenge of maintaining ecosystem function and resiliency to cheatgrass invasion. In 1996 the Bridger-Knoll fire complex on the north Kaibab Plateau burned through critical mule deer (Odocoileus hemionus) native winter range and a majority of this area is now invaded by cheatgrass. We set up a field experiment to test the effectiveness of applications of Imazapic PLATEAU herbicide to control cheatgrass and seeding to restore native shrubs. The shrubs included Wyoming big sagebrush (Artemisia tridentata) and cliffrose (Purshia mexicana). We also set up experiments at the Rocky Mountain Research Station greenhouse to test the effects of PLATEAU on...
ABSTRACT Patches of live, dead, and dying trees resulting from bark beetle-caused mortality alter... more ABSTRACT Patches of live, dead, and dying trees resulting from bark beetle-caused mortality alter spatial and temporal variability in the canopy and surface fuel complex through changes in the foliar moisture content of attacked trees and through the redistribution of canopy fuels. The resulting heterogeneous fuels complexes alter within-canopy wind flow, wind fluctuations, and rate of fire spread. However, there is currently little information about the potential influence of different rates and patterns of mortality on wind flow and fire behavior following bark beetle outbreaks. In this study, we contrasted within-canopy wind flow and fire rate-of-spread (ROS) at two different ambient wind speeds using FIRETEC for two differing bark beetle attack trajectories for a lodgepole pine (Pinus contorta) forest. These two attack trajectories represent different realizations of a bark beetle outbreak and result in different amounts and patterns of mortality through time. Our simulations suggested that the mean within-canopy wind velocities increased through time following the progression of mortality. In addition, we found that for a given level of mortality, a bark beetle outbreak that resulted in a higher degree of aggregation of canopy fuels had greater mean within-canopy wind velocities due to the channeling of wind flow. These findings suggest that bark beetle mortality can influence the mean within-canopy wind flow in two ways: first, by reducing the amount of vegetation present in the canopy acting as a source of drag; and second, by altering spatial patterns of vegetation that can lead to channeling of wind flow. Changes in the fire rate-of-spread were positively related to the level and continuity of bark beetle mortality. Peak rates of spread were between 1.2 and 2.7 times greater than the pre-outbreak scenario and coincided with a high level of mortality and minimal loss of canopy fuels. Following the loss of canopy fuels the rate of fire spread declined to levels below the initial phases of the outbreak in low wind speed cases but remained above pre-outbreak levels in high wind speed cases. These findings suggest that the rate and pattern of mortality arising from a bark beetle outbreak exerts significant influence on the magnitude and timing of alterations to the within-canopy wind flow and rate of fire spread. Our findings help clarify existing knowledge gaps related to the effect of bark beetle outbreaks on fire behavior and could explain potential differences in the reported effects of bark beetle outbreaks on fire behavior through time.
We evaluate the potential for dcndroclimatological reconstruction in the northern Great Plains of... more We evaluate the potential for dcndroclimatological reconstruction in the northern Great Plains of the United States, based on a newly developed network of 23 chronologies of bur oa k (Quercus macrocarpa), ponderosa pine (Pinus ponderosa) and Rocky Mountain juniper (Juniperus scopoulorum) from North Dakota, South Dakota and Iowa. Earliest dates of specimens are AD 1281 for pine, 1597 for juniper,
Numerous wildfires in recent years have highlighted managers' needs for reliable tools to pre... more Numerous wildfires in recent years have highlighted managers' needs for reliable tools to predict postfire mortality of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) trees. General applicability of existing mortality models is uncertain, as researchers have used different sets of variables. We quantified tree attributes, crown and bole fire damage, ground fire severity, and insect presence from a total of
A single ponderosa pine tree found in the central Black Hills of South Dakota revealed its age of... more A single ponderosa pine tree found in the central Black Hills of South Dakota revealed its age of more than 700 years by its tree rings taken from cor- ing in 1992. The purpose of this study was to examine historic climatic pat- terns from the 13th century through most of the 20th century as inferred from ring widths of
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