Seasonal and Habitat Distribution of Tenebrionid Beetles in Shrub-Steppe Communities of the Hanford Site in Eastern Washington

1984 ◽  
Vol 13 (1) ◽  
pp. 214-220 ◽  
Author(s):  
J. K. Sheldon ◽  
L. E. Rogers
2017 ◽  
Vol 26 (6) ◽  
pp. 485 ◽  
Author(s):  
Kirk W. Davies ◽  
Amanda Gearhart ◽  
Chad S. Boyd ◽  
Jon D. Bates

The interaction between grazing and fire influences ecosystems around the world. However, little is known about the influence of grazing on fire, in particular ignition and initial spread and how it varies by grazing management differences. We investigated effects of fall (autumn) grazing, spring grazing and not grazing on fuel characteristics, fire ignition and initial spread during the wildfire season (July and August) at five shrub steppe sites in Oregon, USA. Both grazing treatments decreased fine fuel biomass, cover and height, and increased fuel moisture, and thereby decreased ignition and initial spread compared with the ungrazed treatment. However, effects differed between fall and spring grazing. The probability of initial spread was 6-fold greater in the fall-grazed compared with the spring-grazed treatment in August. This suggests that spring grazing may have a greater effect on fires than fall grazing, likely because fall grazing does not influence the current year’s plant growth. Results of this study also highlight that the grazing–fire interaction will vary by grazing management. Grazing either the fall or spring before the wildfire season reduces the probability of fire propagation and, thus, grazing is a potential fuel management tool.


2014 ◽  
Vol 7 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Phil S. Allen ◽  
Susan E. Meyer

AbstractEcological restoration of shrub–steppe communities in the western United States is often hampered by invasion of exotic annual grasses during the process. An important question is how to create restored communities that can better resist reinvasion by these weeds. One hypothesis is that communities comprised of species that are functionally similar to the invader will best resist invasion, while an alternative hypothesis is that structurally more complex and diverse communities will result in more effective competitive exclusion. In this field experiment, we examined the effects of restored community structure on the invasion success of three annual grass weeds (downy brome, jointed goatgrass, and cereal rye). We created replicated community plots that varied in species composition, structural complexity and density, then seeded in annual grass weeds and measured their biomass and seed production the following year, and their cover after 1 and 3 yr. Annual grass weeds were not strongly suppressed by any of the restored communities, indicating that it was difficult for native species to completely capture available resources and exclude annual grass weeds in the first years after planting. Perennial grass monocultures, particularly of the early seral grass bottlebrush squirreltail, were the most highly invaded communities, while structurally complex and diverse mixtures of shrubs (big sagebrush, rubber rabbitbrush), perennial grasses (bluebunch wheatgrass and bottlebrush squirreltail) and forbs (Lewis flax, Utah sweetvetch, hairy golden aster, gooseberryleaf globemallow) were more resistant to invasion. These results suggest that restoration of sagebrush steppe communities resistant to annual grass invasion benefits from higher species diversity; significant reduction of weed propagule pressure prior to restoration may be required.


2020 ◽  
Vol 29 (8) ◽  
pp. 686
Author(s):  
Kirk W. Davies ◽  
Jon D. Bates

Fire frequency has decreased in many shrub-steppe communities. Re-introducing fire may be needed to increase spatial and temporal variability in vegetation, but is often hindered by concerns of undesired vegetation shifts. These concerns arise, in part, because long-term effects of fire re-introduction in these communities after prolonged fire exclusion and other departures from historical conditions are unknown. To better understand the effects of re-introducing fire, we evaluated plant community response to re-introducing fire for 12 years post fire in six mountain big sagebrush communities. Herbaceous biomass production was 1.7-fold greater in burned compared with unburned areas at the conclusion of the study. Exotic annual grasses appeared to be problematic in the first 8 years post fire, but became inconsequential (~1% cover) by the end of the study. Re-introducing fire promoted other shrubs (excluding sagebrush) that were probably inhibited by competition from sagebrush. Sagebrush cover and density remained low in burned areas for the duration of the study, because of limited recruitment in the years immediately post fire and competition from herbaceous vegetation. Re-introducing fire appears to increase temporal and spatial heterogeneity in shrub-steppe communities experiencing prolonged fire exclusion and, therefore, may be needed to maintain a diversity of plant communities.


2002 ◽  
Vol 83 (2) ◽  
pp. 35
Author(s):  
Robert A. Gitzen ◽  
Janet L. Erickson ◽  
Stephen D. West

1983 ◽  
Vol 10 (3) ◽  
pp. 205-211 ◽  
Author(s):  
William H. Rickard ◽  
Lee E. Rogers

The Bitterbrush-Sagebrush/Cheatgrass vegetation-type occupies about 300 km2 on the US Department of Energy's Hanford Site in the shrub-steppe region of southeastern Washington State. Prior to 1943, part of the land was used for irrigated agriculture and the remainder as grazing land for domestic livestock. In 1943, farming and livestock grazing were terminated and the resident human population was relocated. Use of the land since 1943 has been industrial, mostly for nuclear energy development. The land is not available for public use and shooting of wildlife is prohibited.Nuclear energy development on the Hanford Site consists of a few large buildings that are widely separated, with undeveloped land in between which supports native plants and animals. This undeveloped land provides habitats for native species that are not adapted to intensive irrigated agriculture—a potential use of almost all of the land in the Bitterbrush-Sagebrush vegetation type. The primary disturbance to vegetation is wildfire. Fire destroys Bitterbrush and Sagebrush and these plants are slow to recolonize the burns. Other species are less affected by burning and are capable of quick recovery. The industrial use of the land provides a potential for the ecological study of self-revegetation of abandoned ploughed ground and the response of biota to wildfire.


2019 ◽  
Author(s):  
O G Kalmykova ◽  
G Kh Dusaeva ◽  
N V Maksutova

The intensification of fire regime in the shrub-steppe determined the need for research aimed at identifying the regularities of the effect exerted by wildfires on shrub-steppe ecosystems and one of their most dynamic components referred to as plant cover. A present study was carried out on the territory of Burtinskaya Steppe of the Orenburg Reserve and in its protected area in 2015–2016, following the fire that occurred in August 2014. It was found out that in the first year following a fire event, the total plant cover of steppe ecosystems affected by a wildfire is almost halved. The plant cover dominated by bunchgrasses, especially of the genus Stipa, significantly decreases, and the abundance and diversity of ephemeroids increase. The floristic alteration manifesting itself in the form of an invasive role of certain species (most often ephemeroids and biennials) during one vegetative stage is endemic to the areas exposed to overgrazing in the past. The outburning of plant cover can bring about a change in dominant and codominant plant species within a shrub-steppe assemblage.


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