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1.
Forest thinning and prescribed fire practices are widely used, either separately or in combination, to address tree stocking, species composition, and wildland fire concerns in western US mixed conifer forests. We examined the effects of these fuel treatments alone and combined on dwarf mistletoe infection severity immediately after treatment and for the following 100 years. Thinning, burning, thin + burn, and control treatments were applied to 10 ha units; each treatment was replicated three times. Dwarf mistletoe was found in ponderosa pine and/or Douglas-fir in all units prior to treatment. Stand infection severity was low to moderate, and severely infected trees were the largest in the overstory. Thinning produced the greatest reductions in tree stocking and mistletoe severity. Burning reduced stocking somewhat less because spring burns were relatively cool with spotty fuel consumption and mortality. Burning effects on vegetation were enhanced when combined with thinning; thin + burn treatments also reduced mistletoe severity in all size classes. Stand growth simulations using the Forest Vegetation Simulator (FVS) showed a trend of reduced mistletoe spread and intensification over time for all active treatments. When thinned and unthinned treatments were compared, thinning reduced infected basal area and treatment effects were obvious, beginning in the second decade. The same was true with burned and unburned treatments. Treatment effects on infected tree density were similar to infected basal area; however, treatment effects diminished after 20 years, suggesting a re-treatment interval for dwarf mistletoe.  相似文献   

2.
Forest restoration treatments involving selection harvest and prescribed fire have been applied throughout the Rocky Mountain West with only a limited understanding of how these treatments influence plant community composition and soil processes. Forest restoration treatments, especially those involving fire, have the potential to reduce N capital on site. Unfortunately there has been only limited effort to investigate the effects of forest restoration treatments on forest ecosystem N inputs, especially free living N-fixation in soil and woody residues. Recent studies have highlighted the potential for decaying woody roots to serve as hot spots for N-fixation. The fire and fire surrogates (FFS) study site at Lubrecht Experimental Forest in Western Montana provided a unique opportunity to investigate the effect of restoration treatments on N-fixation. We set out to examine how prescribed fire, selection harvest, and a combination of both influence free living N-fixing bacteria that colonize decomposing woody roots, mineral soil, and soil crusts. Soil, root, and soil crust samples were collected from replicated treatment plots in August 2005 and soil samples were recollected in May 2006 just following snowmelt. Acetylene reduction assays were run on all samples, and extractable inorganic N and potentially mineralizable N (PMN) were measured in mineral soil. While restoration treatments caused an increase in dead roots associated with stumps and fire killed trees, N-fixation rates were nearly non-existent in these root systems. Nitrogen-fixation rates were not significantly influenced by treatments in decomposing woody roots or in mineral soil, but were slightly greater (P < 0.10) in soil crusts when the control stand was compared to treated plots. Nitrogen-fixation rates were also greater in mineral soil than in roots. Soil collected in August exhibited greater rates of N-fixation than soil collected in May which we attributed to higher moisture and an increase in available N following spring thaw. Average rates of free living N-fixation across the treatment plots at Lubrecht were low (0.26 kg N ha−1 year−1), but over time we estimate that these sources, along with the sparse population of symbiotic N-fixing plants and wet N deposition, would replenish soil N lost through fire or harvesting in approximately 40–100 years.  相似文献   

3.
Due to increases in tree density and hazardous fuel loading in Sierra Nevadan forests, land management is focusing on fuel reduction treatments to moderate the risk of catastrophic fires. Fuel treatments involving mechanical and prescribed fire methods can reduce surface as well as canopy fuel loads. Mastication is a mechanical method which shreds smaller trees and brush onto the surface fuel layer. Little data exist quantifying masticated fuel beds. Despite the paucity of data on masticated fuels, land managers desire fuel loading, potential fire behavior and fire effects such as tree mortality information for masticated areas. In this study we measured fuel characteristics before and after mastication and mastication plus prescribed burn treatments in a 25-year old ponderosa pine (Pinus ponderosa C. Lawson) plantation. In addition to surface fuel characteristics and tree data collection, bulk density samples were gathered for masticated material. Regressions were created predicting masticated fuel loading from masticated fuel bed depth. Total masticated fuel load prior to fire treatment ranged from 25.9 to 42.9 Mg ha−1, and the bulk density of masticated fuel was 125 kg m−3. Mastication treatment alone showed increases in most surface fuel loadings and decreases in canopy fuel loads. Masticated treatment in conjunction with prescribed burning reduced both surface and canopy fuel loads. Detailed information on fuel structure in masticated areas will allow for better predictions of fire behavior and fire effects for fire in masticated fuel types. Understanding potential fire behavior and fire effects associated with masticated fuels will allow managers to make decisions on the possibility of mastication to create fuel breaks or enhance forest health.  相似文献   

4.
Vast areas of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) forest in the western United States have become unnaturally dense because of relatively recent land management practices that include fire suppression and livestock grazing. In many areas, thinning treatments can re-establish the natural ecological processes and help restore ecosystem structure and function. Precipitous global climate change has focused attention on the carbon storage in forests. An unintended consequence of fire suppression has been the increased storage of carbon in ponderosa stands. Thinning treatments reduce standing carbon stocks while releasing carbon through the combustion of fuel in logging machinery, burning slash, and the decay of logging slash and wood products. These reductions and releases of stored carbon must be compared to the risk of catastrophic fire burning through the stand and releasing large quantities of carbon to the atmosphere to more fully understand the costs and benefits – in carbon terms – of forest restoration strategies.  相似文献   

5.
6.
Euro-American logging practices, intensive grazing, and fire suppression have increased the amount of carbon that is stored in ponderosa pine (Pinus ponderosa Dougl. Ex Laws) forests in the southwestern United States. Current stand conditions leave these forests prone to high-intensity wildfire, which releases a pulse of carbon emissions and shifts carbon storage from live trees to standing dead trees and woody debris. Thinning and prescribed burning are commonly used to reduce the risk of intense wildfire, but also reduce on-site carbon stocks and release carbon to the atmosphere. This study quantified the impact of thinning on the carbon budgets of five ponderosa pine stands in northern Arizona, including the fossil fuels consumed during logging operations. We used the pre- and post-treatment data on carbon stocks and the Fire and Fuels Extension to the Forest Vegetation Simulator (FEE-FVS) to simulate the long-term effects of intense wildfire, thinning, and repeated prescribed burning on stand carbon storage.The mean total pre-treatment carbon stock, including above-ground live and dead trees, below-ground live and dead trees, and surface fuels across five sites was 74.58 Mg C ha−1 and the post-treatment mean was 50.65 Mg C ha−1 in the first post-treatment year. The mean total carbon release from slash burning, fossil fuels, and logs removed was 21.92 Mg C ha−1. FEE-FVS simulations showed that thinning increased the mean canopy base height, decreased the mean crown bulk density, and increased the mean crowning index, and thus reduced the risk of high-intensity wildfire at all sites. Untreated stands that incurred wildfire once within the next 100 years or once within the next 50 years had greater mean net carbon storage after 100 years compared to treated stands that experienced prescribed fire every 10 years or every 20 years. Treated stands released greater amounts of carbon overall due to repeated prescribed fires, slash burning, and 100% of harvested logs being counted as carbon emissions because they were used for short-lived products. However, after 100 years treated stands stored more carbon in live trees and less carbon in dead trees and surface fuels than untreated stands burned by intense wildfire. The long-term net carbon storage of treated stands was similar or greater than untreated wildfire-burned stands only when a distinction was made between carbon stored in live and dead trees, carbon in logs was stored in long-lived products, and energy in logging slash substituted for fossil fuels.  相似文献   

7.
The capacity of prescribed fire to restore forest conditions is often judged by changes in forest structure within a few years following burning. However, prescribed fire might have longer-term effects on forest structure, potentially changing treatment assessments. We examined annual changes in forest structure in five 1 ha old-growth plots immediately before prescribed fire and up to eight years after fire at Sequoia National Park, California. Fire-induced declines in stem density (67% average decrease at eight years post-fire) were nonlinear, taking up to eight years to reach a presumed asymptote. Declines in live stem biomass were also nonlinear, but smaller in magnitude (32% average decrease at eight years post-fire) as most large trees survived the fires. The preferential survival of large trees following fire resulted in significant shifts in stem diameter distributions. Mortality rates remained significantly above background rates up to six years after the fires. Prescribed fire did not have a large influence on the representation of dominant species. Fire-caused mortality appeared to be spatially random, and therefore did not generally alter heterogeneous tree spatial patterns. Our results suggest that prescribed fire can bring about substantial changes to forest structure in old-growth mixed conifer forests in the Sierra Nevada, but that long-term observations are needed to fully describe some measures of fire effects.  相似文献   

8.
We studied the combined effects of thinning on stand structure, growth, and fire risk for a Scots pine thinning trial in northern Spain 4 years following treatment. The thinning treatments were: no thinning, heavy thinning (32–46% of basal area removed) and very heavy thinning (51–57% of basal area removed). Thinning was achieved via a combination of systematic and selective methods by removing every seventh row of trees and then by cutting suppressed and subdominant trees in the remaining rows (i.e., thinning from below). Four years after thinning, mean values and probability density distributions of stand structural indices showed that the heavier the thinning, the stronger the tendency towards random tree spatial positions. Height and diameter differentiation were initially low for these plantations and decreased after the 4-year period in both control and thinned plots. Mark variograms indicated low spatial autocorrelation in tree diameters at short distances. Diameter increment was significantly correlated with the inter-tree competition indices, and also with the mean directional stand structural index. Two mixed models were proposed for estimating diameter increment using a spatial index based on basal area of larger trees (BALMOD) in one model versus spatial competition index by Bella in the other model. As well, a model to estimate canopy bulk density (CBD) was developed, as this variable is important for fire risk assessment. Both heavy and very heavy thinning resulted in a decrease of crown fire risk over no thinning, because of the reduction in CBD. However, thinning had no effect on the height to crown base and thus on the flame length for torching. Overall, although thinning did not increase size differentiation between trees in the short term, the increase in diameter increment following thinning and the reduction of crown fire risks support the use of thinning. Also, thinning is a necessary first step towards converting Scots pine plantations to more natural mixed broadleaved woodlands. In particular, the very heavy thinning treatment could be considered a first step towards conversion of overstocked stands.  相似文献   

9.
Regional conservation planning frequently relies on general assumptions about historical disturbance regimes to inform decisions about landscape restoration, reserve allocations, and landscape management. Spatially explicit simulations of landscape dynamics provide quantitative estimates of landscape structure and allow for the testing of alternative scenarios. We used a landscape fire succession model to estimate the historical range of variability of vegetation and fire in a dry forest landscape (size ca. 7900 km2) where the present-day risk of high severity fire threatens the persistence of older closed canopy forest which may serve as Northern Spotted Owl (Strix occidentalis caurina) habitat. Our results indicated that historically, older forest may have comprised the largest percentage of the landscape (∼35%), followed by early successional forest (∼25%), with about 9% of the landscape in a closed canopy older forest condition. The amount and condition of older forest varied by potential vegetation type and land use allocation type. Vegetation successional stages had fine-grained spatial heterogeneity in patch characteristics, with older forest tending to have the largest patch sizes among the successional stages. Increasing fire severities posed a greater risk to Northern Spotted Owl habitat than increasing fire sizes or frequencies under historical fire regimes. Improved understanding of historical landscape-specific fire and vegetation conditions and their variability can assist forest managers to promote landscape resilience and increases of older forest, in dry forests with restricted amounts of habitat for sensitive species.  相似文献   

10.
The loss of natural forest habitats due to forestry is the main reason for the decline in boreal forest biodiversity of the Nordic countries of Europe. Ecological rehabilitation may provide means to recover and sustain biodiversity. We analyzed the effects of controlled burning and dead-wood creation (DWC) on the diversity of pioneer wood-inhabiting fungi in managed Norway spruce (Picea abies) forests in southern Finland. Altogether 18 stands were first subjected to a partial cutting with ordinary logging residues in form of cut stumps and treetops left on site. The subsequent rehabilitation treatments consisted of a controlled burning applied in half of the stands and three levels of dead-wood creation (5, 30 and 60 m3 ha−1). The DWC involved creation of logs; felling of whole trees to mimic downed logs formed by natural disturbance processes. Each treatment was replicated three times. Inside each stand, substrates were sampled in two different biotopes; one on mineral soil and one on mineral soil with a thin peat layer. We surveyed the fungal flora on the logs (n = 364) and the ordinary residue stumps (n = 1767) and tops (n = 845) five years after the treatments.When comparing different stands, controlled burning had a significant effect on species composition; certain species were significantly more frequent on substrates in burned stands than in unburned stands, indicating that these species were favored by controlled burning. By contrast, we found no significant effects of DWC levels or biotope on species composition or richness. When comparing different substrates, 99% of the logs hosted at least one species and the occurrence probability of certain species was significantly higher on logs than on ordinary residue stumps and tops. Yet, volume-based rarefaction analyses showed that residues were more species dense than the logs, indicating that ordinary logging residues constitute important resources for many pioneer species.We conclude that controlled burning combined with DWC have strong effects on biodiversity; it modifies the composition of the pioneer wood-inhabiting fungal species found in managed forests and may thereby also influence the further succession and diversity of the secondary fungal flora.  相似文献   

11.
Leaf nitrogen content (Nmass, %) and leaf mass per area (LMA, g m−2) are two important features that are closely linked to the photosynthetic performance of plants and, thus, the NPP of forest ecosystems. Forest management practices, such as burning and thinning, change stand structure and soil dynamics, which may result in changes in Nmass and LMA. The objective of this study was to understand how Nmass and LMA of seven canopy tree species/genus (Quercus alba, Q. coccinea, Q. prinus, Q. velutina, Carya spp., Acer rubrum, and Liriodendron tulipifera) responded to (i) thinning and/or burning treatments and to (ii) different landscape and soil properties in southern Ohio. We collected leaves from the top, and bottom, of five individuals of each taxa in each treatment unit. Leave traits (Nmass and LMA) were compared using analysis of variance followed by orthogonal contrasts. To further understand the factors that influence the canopy leaf traits, we used regression tree analysis (RTA) to examine how variations of LMA and Nmass were linked to thinning and/or burning treatments, soil, and landscape variables. Finally, we assessed the potential ramifications of changes in these traits on canopy carbon budgets using a PnET-Day model, which is a daily time-step canopy carbon exchange model. We found significant effects of thinning, burning, and their interactions on LMA at the bottom of the crown while none of the treatments showed significant effects on LMA at the top of the crown. Nmass responded significantly to only burning treatment. RTA results exhibited minor effects of landscape features and soil properties on Nmass and LMA. Interspecific differences accounted for most variations of both leaf traits. Sensitivity analysis of PnET-Day model suggested these subcanopy changes in LMA increased the annual net primary production (NPP) by 8%. In summary, our results suggest that forest management can substantially influence canopy leaf traits such as Nmass and LMA and that alteration of these traits can influence forest NPP. Given the role of forests as global carbon sinks, the potential influence of thinning and burning on canopy traits, and thus NPP, is an important consideration for forest management.  相似文献   

12.
Prescribed fire is an important tool in the management of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) forests, yet effects on bark beetle (Coleoptera: Curculionidae, Scolytinae) activity and tree mortality are poorly understood in the southwestern U.S. We compared bark beetle attacks and tree mortality between paired prescribed-burned and unburned stands at each of four sites in Arizona and New Mexico for three growing seasons after burning (2004–2006). Prescribed burns increased bark beetle attacks on ponderosa pine over the first three post-fire years from 1.5 to 13% of all trees, increased successful, lethal attacks on ponderosa pine from 0.4 to 7.6%, increased mortality of ponderosa pine from all causes from 0.6 to 8.4%, and increased mortality of all tree species with diameter at breast height >13 cm from 0.6 to 9.6%. On a per year basis, prescribed burns increased ponderosa pine mortality from 0.2% per year in unburned stands to 2.8% per year in burned stands. Mortality of ponderosa pine 3 years after burning was best described by a logistic regression model with total crown damage (crown scorch + crown consumption) and bark beetle attack rating (no, partial, or mass attack by bark beetles) as independent variables. Attacks by Dendroctonus spp. did not differ significantly over bole heights, whereas attacks by Ips spp. were greater on the upper bole compared with the lower bole. Three previously published logistic regression models of tree mortality, developed from fires in 1995–1996 in northern Arizona, were moderately successful in predicting broad patterns of tree mortality in our data. The influence of bark beetle attack rating on tree mortality was stronger for our data than for data from the 1995–1996 fires. Our results highlight canopy damage from fire as a strong and consistent predictor of post-fire mortality of ponderosa pine, and bark beetle attacks and bole char rating as less consistent predictors because of temporal variability in their relationship to mortality. The small increase in tree mortality and bark beetle attacks caused by prescribed burning should be acceptable to many forest managers and the public given the resulting reduction in surface fuel and risk of severe wildfire.  相似文献   

13.
Prescribed burning is used in many fire-prone ecosystems for wildfire mitigation and conservation of biodiversity. However, there is limited information about how biota responds to long-term fire management, especially at a whole-of-community level. We studied community responses to different fire interval sequences resulting from planned and unplanned fires in Mediterranean-climate ecosystems in the Warren bioregion of south-west Western Australia (SWA) to determine the resilience of the biota to contrasting fire regimes. Fire history data were used to identify contrasting fire interval sequences in forest and shrubland communities for the period 1972-2004. We surveyed vascular plants, ants, beetles, vertebrates and macrofungi at 30 sites to investigate community-level responses to consecutive short (SS: ≤5 years), consecutive long (LL: ≥10 years), one very long (VL: 30 years), or mixed/moderate (M: 6-9 years) fire interval(s). All sites had a common time-since-fire of ∼4 years at the commencement of sampling which was conducted over two years. Species richness and composition differed between forest and shrubland communities, but the influence of fire interval sequences on taxonomic groups was minimal and difficult to detect. There was weak evidence of compositional differences between SS and LL/VL regimes for plants, ants, beetles and macrofungi but no difference between these regimes and the intermediate disturbance M-regime. These results demonstrate the resilience of the biota in open forests and shrublands of SWA to contrasting fire interval sequences over the past 30 years. We conclude that occasional short (3-5 years) intervals between fires are unlikely to have a persistent effect on community composition, though maintaining a regime of short or long intervals may alter species composition and/or abundance. We suggest that variability in fire intervals is important for long-term conservation of the biota. For the Warren Region, prescribed burning at an intermediate level of disturbance and incorporating variability in interval length is recommended to achieve the dual objectives of wildfire mitigation and biodiversity conservation.  相似文献   

14.
The importance of structural complexity in forest ecosystems for ecosystem diversity has been widely acknowledged. Tree microhabitat structures as indicators of biodiversity, however, have only seldom been the focus of diversity research although their occurrence is highly correlated with the abundance of forest species and ecosystem functions. In this study, microhabitat structures in Douglas-fir (Pseudotsuga menziesii) forests were defined and their frequency and abundance in natural stands and stands of varying active management histories and stand ages was compared. Indicator microhabitat structures for natural forests were determined and the relationship of the abundance of microhabitat structures with tree diameter of Douglas-fir trees was analysed.  相似文献   

15.
I examined contrasts in response to moderate-intensity fire between two pine species (Pinus leiophylla Schiede and Deppe and P. engelmannii Carr.) and four oak species (Quercus hypoleucoides Camus., Q. arizonica Sarg., Q. emoryi Torr., and Q. rugosa Nee.) in Madrean forests in southeastern Arizona. Stem survival of pines after fire was greater than for oaks, but oaks sprouted more successfully after top-kill than did the only sprouting pine species, P. leiophylla. As a result, post-fire decline and subsequent recovery in oak populations was more marked than for the pines, and the ratio of oaks to pines decreased as a result of fire but increased during recovery. In typical forest stands, most individuals established from 1860 to 1920 at the interface between a period of high fire frequency and the onset of fire exclusion. Ages of Q. hypoleucoides were more clustered than for the pines, suggesting post-fire sprouting rather than long-term top-survival of fire. The results point to contrasts in mechanisms of persistence in this fire-prone ecosystem: fire resistance in the pines versus post-fire sprouting in the oaks. As a result, fire regime controls the balance between the two groups, with moderate-intensity fire favoring the pines and periods of low fire frequency – due to natural causes or anthropogenic fire exclusion – favoring the oaks. The species and community response patterns found in this study may apply generally to other pine-oak communities.  相似文献   

16.
lNTRODUCTIONTherhythInofKorcanpinegrowingandtrpearchitectUreissubjectedtoitsownl1crcd-ityandforeststructUre.Tl1cil11portantefTcctsofgapdynamicsarethereasonsthatmaketl1cKoreanpinetrceformhighqualityoftimbcr.Whilecurrentn1anagemcntofKoreanpincforestmainlyfocusesonpurestand,thccco-logicalrelationshipsbetWcenKoreanpineandothcrsPecicsinaconununityareneglected,thcprimitivebiologicalconditionislost.TheKo-reanpinetrecsinplantationcasilydivergeonthctOpofmainsten1,thesescverelyaITectthcgrOedqu…  相似文献   

17.
18.
We used pre- and post-burn fire effects data from six prescribed burns to examine post-burn threshold effects of stand structure (understory density, overstory density, shrub cover, duff depth, and total fuel load) on the regeneration of yellow pine (Pinus subgenus Diploxylon) seedlings and cover of herbaceous vegetation in six prescribed-fire management units located within western Great Smoky Mountains National Park (GSMNP) in east Tennessee, USA. We also evaluated the utility of the Keetch-Byram Drought Index (KBDI) as a predictor of post-burn stand and fuel conditions by comparing post-burn stand variables for different ranges of KBDI (23-78; more wet, and 328-368; more dry). We found that yellow pine seedlings were effectively absent in post-burn forests until overstory density was reduced over 40%, understory density was reduced over 80%, and post-burn shrub cover was 10% or less. We also observed that a reduction in total fuels of 60% and a post-burn duff layer depth of less than four cm were required for successful regeneration of yellow pine. Total herbaceous species cover exhibited near identical responses with increased cover following an 80% reduction in understory density and a post-burn duff depth of less than 4 cm. We observed strong positive relationships between high KBDI values and burn severity, changes in forest structure, reductions in fuels, and post-burn yellow pine reproduction. We observed continuous recruitment of yellow pine seedlings 5 years after fire in high KBDI burns while low KBDI burns showed little change in yellow pine density through time. An intense outbreak of the southern pine beetle (SPB; Dendroctonus frontalis) occurred within 2 years of our high KBDI burns and reduced shading resulting from overstory mortality likely enhanced the survival of yellow pine seedlings. The results of this study provide targets for the application of prescribed fire to restore yellow pine in the southern Appalachians. Continued research and monitoring will help determine how prescribed fire can best be applied in combination with other disturbance agents such as SPB to perpetuate yellow pine forests.  相似文献   

19.
Prescribed burning is advocated for the sustainable management of fire-prone ecosystems for its capacity to reduce fuel loads and mitigate large high-intensity wildfires. However, there is a lack of comprehensive field evidence on which to base predictions of the benefits of prescribed burning for meeting either wildfire hazard reduction or conservation goals. Australian eucalypt forests are among the very few forest types in the world where prescribed burning has been practised long enough and at a large enough spatial scale to quantify its effect on the incidence and extent of unplanned fires. Nevertheless even for Australian forests evidence of the effectiveness of prescribed burning remains fragmented and largely unpublished in the scientific literature.  相似文献   

20.
Treatments to restore understory plant communities of mature (50–80-year old) longleaf pine (Pinus palustris Mill.) and reduce risks of wildfire were applied to 10 ha plots that had a substantial shrub layer due to lack of fire. Plots were located in the Coastal Plain of Alabama and treatments consisted of: (1) untreated control, (2) growing season prescribed burn, (3) thin only, (4) thin plus growing season burn, and (5) herbicide plus growing season burn. Thin plus burn plots had significantly higher tree mortality compared to burn only and control plots and, overall, fire was the primary cause of tree death. Most tree mortality occurred within 1-year of treatment. From 2002 to 2004, we captured 75,598 Coleoptera in multiple funnel traps comprising 17 families and 130 species. Abundance of all Coleoptera combined was not different among treatments. Species richness was significantly higher on thin plus burn plots compared to thin only and control plots. Scolytinae (Coleoptera: Curculionidae) were more abundant on thin plus burn plots compared to control plots in fall 2002 but in fall 2003 they were more abundant on thin plus burn, thin only, and herbicide plus burn compared to controls. Among Scolytinae, Dendroctonus terebrans (Olivier), Xyleborinus saxeseni (Ratzeburg), Xyleborus sp. 3, and Hylastes tenuis (Eichhoff), showed varying responses to the treatments. Other Curculionidae were significantly more abundant on thin only and herbicide plus burn plots compared to all other treatments in spring 2003 and in spring 2004 they were more abundant on herbicide plus burn plots compared to thin plus burn treatments. Among Cerambycidae, Xylotrechus sagittatus (Germar) was higher in abundance in fall 2003 on thin plus burn plots compared to all other treatments except herbicide plus burn plots. Within the predator complex, Trogositidae were higher on thin plus burn plots compared to all other treatments except thin only plots in spring 2003, and Cleridae abundance was higher in spring 2004 on burn only plots compared to all other treatments. Linear regression analyses of dead trees per plot versus various Coleoptera showed captures of Buprestidae, Cerambycidae, Trogositidae, Acanthocinus nodosus (Fabricius), Temnochila virescens (Fabricius), and X. saxeseni increased with increasing number of dead trees. Our results show that the restoration treatments tested did not cause increased bark beetle-related tree mortality and they did not negatively affect populations of early successional saproxylic beetle fauna.  相似文献   

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