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271. [Article] New insights on an old topic : understanding the effects of forest harvest on trout in the context of climate
Studies of the effects of forest harvest on streams and fish have a long history in the Pacific Northwest. Results of this work have prompted development of new forest harvest practices that are more protective ...Citation Citation
- Title:
- New insights on an old topic : understanding the effects of forest harvest on trout in the context of climate
- Author:
- Penaluna, Brooke E.
Studies of the effects of forest harvest on streams and fish have a long history in the Pacific Northwest. Results of this work have prompted development of new forest harvest practices that are more protective of these resources, but the effectiveness of these new practices has not been fully evaluated. Furthermore, the effects of contemporary forest harvest in the context of climate change are poorly understood. To address these issues, my overall research goal was to understand how water quality, water quantity, and instream habitat influence individuals and corresponding population dynamics of coastal cutthroat trout (Oncorhynchus clarkii clarkii). My work was designed to complement field results from a new generation of watershed studies currently underway in western Oregon. I combined semi-natural experiments with modeling based on field observations to understand fundamental causes and processes influencing trout. This multifaceted approach provided a novel process-based perspective on issues related to forest harvest and climate. In Chapter 2, I evaluated individual- and population-level responses of coastal cutthroat trout to instream cover. Although the influences of forest harvest on stream flow, temperature, and turbidity are often the focus, instream cover may be strongly influenced by forest harvest. In addition, restoration of instream cover is now a common practice, but the importance of cover itself to stream-living fishes is still a major question. To address this issue, I conducted large-scale manipulative experiments in outdoor semi-natural stream units to approximate conditions experienced by trout in headwater streams in western Oregon. I determined that infrequent cover use by trout leads to emigration. Next, I built upon key ideas within stream ecology related to the importance of location within a landscape to aquatic biota, which have been explored and debated extensively. The variability in population responses across similar locations within a landscape is less understood. My objective in Chapter 3 was to understand the variability in population biomass of coastal cutthroat trout across headwater streams by understanding of the relative roles of two general classes of variables that occur in headwater streams: dynamic environmental regimes and relatively fixed habitat structure. I provided evidence that environmental regimes contribute to biomass variability while also being constrained by the habitat structure, given the range of conditions that I was able to simulate. Although the effects of contemporary forest harvest and climate change occur simultaneously, they are not typically considered together, as they are in Chapter 4. Here, I tracked population responses of trout, including biomass, survival, growth, and timing of emergence during six decades across four modeled headwater streams using the same individual-based trout model as in Chapter 3. I modeled four scenarios: 1) baseline conditions (simulation of existing conditions); 2) effects of contemporary forest harvest; 3) effects of climate change; and 4) the combined effects of forest harvest and climate change. Differences among scenarios were tied to changes in flow and temperature regimes. Here, I found that there was a high degree of local variability in the responses that I simulated. Whereas localized responses to forest harvest have been observed, my findings contrast with the vast majority of work on species responses to climate change, most of which reports relatively synchronous or uniform responses. I highlighted the role of individual variability of trout and local variability of streams, which ultimately suggest that some individuals and populations of trout may be more vulnerable than others to the effects of forest harvest, climate change, or both processes together.
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272. [Article] After the Flow: Landscape Response to the Emplacement of Holocene Lava Flows, Central Oregon Cascades, USA
Effusive volcanic eruptions repave landscapes rapidly with lava flows, resetting the underlying landscape and ecosystem. The unique physical properties of lava pose interesting challenges for recovery, ...Citation Citation
- Title:
- After the Flow: Landscape Response to the Emplacement of Holocene Lava Flows, Central Oregon Cascades, USA
- Author:
- Deligne, Natalia
- Year:
- 2012
Effusive volcanic eruptions repave landscapes rapidly with lava flows, resetting the underlying landscape and ecosystem. The unique physical properties of lava pose interesting challenges for recovery, as lava flows can be highly permeable while lava itself is dense, sterile, and generally inhospitable towards life. This dissertation examines two aspects of landscape recovery following lava flow emplacement: (1) hydrologic adaptation of surface and groundwater to recent volcanism and (2) plant colonization of young lava flows. I examine two sites in the central Oregon Cascades: the c. 3 ka Sand Mountain volcanic field (SMVF), located in the headwaters of the McKenzie River, a critical water resource for the state of Oregon, and the c. 1.5 ka Collier Cone lava flow, originating on the north flanks of North Sister volcano. My investigation of the SMVF and upper McKenzie River watershed reveals a complex volcanic history with profound impacts on the configuration and short-term discharge of the McKenzie River: lava flows from the SMVF and other Holocene vents have buried, dammed, and altered the path of the McKenzie River. Moreover, given the large groundwater contribution from the SMVF to the McKenzie River, I estimate that SMVF activity caused McKenzie River discharge in present-day Eugene, Oregon to decrease by up to 20% for days to months at a time; future regional mafic volcanic activity could have a similar impact. The SMVF and the Collier Cone lava flow are notable for the juxtaposition of barren exposed lava and mature forests on the same or similarly aged lava flows. I use a combination of LiDAR analysis, field observations, and soil characterization to examine soil and vegetation at these two sites and find that the presence of an external soil source greatly facilitates plant establishment, growth, and survival. Here, external soil sources are syn- or post-eruptive tephra (SMVF) or flood-borne deposits (Collier Cone lava flow). External soil appears to provide a substrate for plants to grow in along with key nutrients and sufficient moisture; overall, external soil sources are key for the initial recovery following an effusive volcanic disturbance. This dissertation includes co-authored material submitted for publication.
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The role of detritivores in the conversion of allochthonous leaf material in two small streams in the Cascade Range of Oregon was studied. Their importance in relation to other consumers was estimated ...
Citation Citation
- Title:
- The conversion of allochthonous material by stream detritivores
- Author:
- Grafius, Edward John
The role of detritivores in the conversion of allochthonous leaf material in two small streams in the Cascade Range of Oregon was studied. Their importance in relation to other consumers was estimated from emergence and benthic standing crop data. Ingestion rates and efficiencies of utilization of bigleaf maple (Acer macrophyllum) and red alder (Alnus rubra) leaves by several species of stream detritivores, one species of stonefly and several species of caddis lies, were measured under field or laboratory conditions. Mean consumption rates varied from 0. 04 mg/mg/day for Halesochila taylori larvae (Trichoptera:Limnephilidae) feeding on maple leaves to 0.60 mg /mg /day' for Lepidostoma sp. larvae (Trichoptera :Lepidostomatidae) feeding on alder and maple leaves. Ecclisomyia sp. larvae (Trichoptera:Limnephilidae) consumed 0.10 mg/mg/day of maple leaves in the field. All consumption rates were calculated assuming constant feeding rates by the insects and constant rates of leaf decomposition without insects, but a model is discussed that allows non-linear feeding and leaf decomposition rates. Efficiency of food utilization was measured either as assimilation efficiency, the ratio of assimilated food (ingestion minus egestion) to consumption; or as gross growth efficiency, the slope of the growth:consumption line calculated by linear regression analysis. Assimilation efficiencies ranged from 7.4% for Heteroplectron californicum larvae (Trichoptera:Calamoceratidae) fed on maple leaves to 12% for Lepidostoma sp. larvae fed on alder and maple leaves. In order to assess the role of microbial communities in leaf utilization by Pteronarcys princeps (Plecoptera:Pteronarcidae), nymphs were fed untreated maple leaves and maple leaves treated to reduce bacterial or fungal populations, for a period of 54 days. Gross growth efficiency when fed on untreated leaves was 4.94% compared with 1.03% for the insects fed antibacterial treated leaves. When fed fungicide treated leaves, the mean consumption rate was less than 10% of the consumption of untreated leaves and mortality was 85% compared with 15% for the insects fed untreated leaves. It was concluded that bacteria play a major role in the utilization of leaves by Pteronarcys princeps and that fungi are important as astimulus to feeding, although they may also aid in utilization of the leaves. To aid in classifying the emergence and benthos data into trophic categories, an extensive literature review of the foods of aquatic insects was compiled. The estimated yearly emergence of aquatic insects from Watershed 10 was 81 mg/m² /yr. of algivores, 253 mg/m²/yr. of detritivores, and 135 mg/m²/yr. of carnivores. The mean standing crop of aquatic insects in an old-growth location in Mack Creek was 0.85 g/m² of algivores, 3.10 g/m² of detritivores, and 2.31 g/m² of carnivores; and 0.83 g/m² of algivores, 1.57 g/m² of detritivores, and 4.04 g/m² of carnivores in a clear-cut location. A model is included describing the cycling of energy within the detrital component of the stream system, reflecting the importance of the fecal material and leaf fragments that return to the detrital pool.
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MIKE SHE is a fully distributed, physically-based hydrologic model that can simulate water movement over and under the Earth's surface. Evapotranspiration (ET) is one of the components of this model. MIKE ...
Citation Citation
- Title:
- Use of MIKE SHE for estimation of evapotranspiration in the Sprague River Basin
- Author:
- Shakya, Suva R.
MIKE SHE is a fully distributed, physically-based hydrologic model that can simulate water movement over and under the Earth's surface. Evapotranspiration (ET) is one of the components of this model. MIKE SHE uses a modification of the Kristensen -Jensen (1975) method to calculate actual ET. This method is based on addition of the three evapotranspiration components – interception storage, transpiration by the plant and evaporation from the soil surface, to compute total actual evapotranspiration. The validity of the Kristensen-Jensen method has been tested on an arid region within the Sprague River subbasin of the Upper Klamath basin in southern Oregon. The model was setup on a 1,000 m by 1,000 m flat surface as a one-dimensional grid cell. There are sixteen computation layers which make three soil profile layers with varying soil properties. Meteorological data from the Pacific Northwest Cooperative Agricultural Weather Network (AgriMet) were used to setup the model. Soil physical properties were taken from the Soil Survey Geographic (SSURGO) database of the Natural Resources Conservation Service (NRCS). Values of the van Genuchten parameters for soil water retention and hydraulic conductivity as a function of soil texture from Carsel and Parrish (1988) were applied. Wetland vegetation such as duckweed and cattail, natural vegetation such as big sagebrush, ponderosa pine and juniper, and agricultural crops such as grass pasture and maize were used to test MIKE SHE evapotranspiration simulation. The length of growth stage, crop coefficient, leaf area index (LAI) and root depth values were taken from the literature. Actual crop ET rates were calculated based on AgriMet reference ET which uses the Kimberly Penman (Wright, 1982) method. The alfalfa reference ET was converted to a grass reference by multiplying by a factor of 0.833 (Jensen et al., 1990). The single crop coefficient method was used and soil stress was accounted for using the FAO 56 method (Allen et al, 1998). Simulated irrigation was applied to maize and grass to keep the root zone soil moisture close to field capacity. Crop ET rates from the MIKE SHE simulation were then compared to the AgriMet based ET rates, resulting in a comparison of Kristensen-Jensen method against the Kimberly Penman method. Both the Kristensen-Jensen and AgriMet simulation scenarios were driven by the same reference ET and the same FAO 56 basal crop coefficient. Differences are therefore a function of different methods for dealing with soil moisture stress. Results indicate that the MIKE SHE simulated evapotranspiration corresponds to the Kimberly Penman method for the duckweed and cattail wetlands species with resulting Nash and Sutcliffe (NS) efficiencies of 0.97 and 1.00, respectively. The big sagebrush, juniper, and ponderosa pine species required a soil stress correction factor for the crop coefficients and the results yielded NS efficiency values of 0.14, 0.59 and 0.68, respectively. Irrigation was automatically turned on for maize at a 20 percent soil moisture deficit to minimize the effects of water stress and the resulting NS efficiency was 0.85. For pasture, an irrigation based on average monthly water deficit for pasture in Klamath was used (Cuenca et al.,1992). This resulted in a NS efficiency of 0.77. Each crop requires unique treatment within the model. Required vegetation parameters such as crop coefficient and LAI, climatic factors such as reference ET, and soil hydraulic properties need to be based on local conditions to the extent possible. It should be noted that the MIKE SHE simulations were run in a one-dimensional mode which precluded accounting for spatial variability or lateral flow of surface or groundwater. The simulation results indicate that converting the study area into a well irrigated pasture would require application of substantial amounts of irrigation water by sprinkler or flooding. Wetlands would require even more water to flood the land, but would be well suited for development of regional habitat. Big sagebrush, juniper and ponderosa pine survive under natural conditions but experience considerable plant stress brought on by soil water deficits which limit plant production below the maximum possible growth.
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275. [Article] Developing techniques for evaluating the susceptibility of root-disease resistant Port-Orford-Cedar to foliar and stem canker diseases.
Since around 1923 Port-Orford-cedar (Chamaecyparis lawsoniana (A. Murray) Parl.) has been affected by Phytophthora root disease caused by the virulent introduced pathogen Phytophthora lateralis. A systematic ...Citation Citation
- Title:
- Developing techniques for evaluating the susceptibility of root-disease resistant Port-Orford-Cedar to foliar and stem canker diseases.
- Author:
- Martin, Danielle K. H.
Since around 1923 Port-Orford-cedar (Chamaecyparis lawsoniana (A. Murray) Parl.) has been affected by Phytophthora root disease caused by the virulent introduced pathogen Phytophthora lateralis. A systematic resistance testing and breeding program located at the USDA Forest Service Dorena Genetic Resource Center in Cottage Grove, Oregon was initiated in 1997 with the goal of producing Phytophthora root disease resistant planting stock suitable for replacing wild native POC killed by the disease. Although families of Port-Orford-cedar have been identified as having a heritable form of resistance to Phytophthora lateralis, there is concern that susceptibility to other pathogens of Port-Orford-cedar, such as Seiridium sp. and Stigmina thujina, could compromise the success of deploying root disease resistant planting stock. This thesis examines methods used to evaluate the heritability of susceptibility of Port-Orford-cedar families in the Phytophthora root disease resistance breeding program to infection and disease caused by species of Seiridium and Stigmina thujina. Inoculation studies were undertaken to investigate the feasibility of developing protocols for screening Phytophthora root disease resistant POC for resistance to cypress canker caused by species of Seiridium and foliage blight caused by Stigmina thujina. Procedures were developed for culturing the pathogens, producing viable spores, and developing inoculation and disease rating procedures. In addition, the species of Seiridium associated with cypress canker of Port-Orford-cedar in Oregon was examined by observing morphological characteristics and comparing ß-tubulin and histone gene sequences. Cypress canker symptom severity was compared among 30 POC families with differing susceptibility to Phytophthora root disease. Seedlings were wound inoculated with cultures of a Seiridium sp. isolated from symptomatic POC and resulting symptoms scored monthly over the following 12 months. Symptoms of infection began to develop within two months after inoculation. Symptoms began as slight chlorosis of foliage above the site of inoculation, progressed to a darker browning of foliage, and finally resulted in seedling death. One year post inoculation about 71% of seedlings had been killed. Average between-family mortality ranged from 46 to 89% with a grand mean mortality of 52%. A multifactor ANOVA showed a significant variation in mortality among families. No correlation between resistance to Seiridium and resistance to P. lateralis was found. Variation in susceptibility to Stigmina foliage blight was also examined for the same 30 families. Port-Orford-cedar seedlings were inoculated by exposure to natural inoculum at a field site or by aerosol application of macerated mycelium of S. thujina cultures to seedling foliage in a greenhouse study and evaluated for Stigmina blight symptoms after 12 months. Stigmina symptoms were also compared in a naturally infected POC common garden plantation representing a range-wide collection of Port- Orford-cedar. Differences in symptom severity between families were found for all three assays. However, with one exception, no correlation was found between resistance to infection by Stigmina thujina and resistance to P. lateralis. Seedstock collected from watersheds that differed in elevation, precipitation, latitude and longitude were found to have significant variation in levels of disease severity caused by S. thujina. Families from watersheds nearest to the coast, from more northern latitudes and lower elevations showed lower levels of S. thujina disease symptoms. POC seedlings from parent trees located in watersheds in the southernmost, most inland provenances, higher elevations and lower mean annual precipitation (mm) had higher Stigmina disease ratings. In order to identify the species of Seiridium associated with cypress canker in Oregon, eight isolates of Seiridium were collected from three host species in various plantations in southwest Oregon. The diagnostic features of the Seiridium isolates were morphologically most similar to those described for S. cardinale. However, phylogenetic analysis based on ß-tubulin and histone gene sequences grouped the Oregon isolates in a separate clade from S. cardinale isolates. The Oregon Seiridium isolates occurred in a sister relationship with S. unicorne isolates from Portugal. The lack of agreement between the morphological characteristics of the Oregon Port-Orford cedar isolates and the phylogenetic analysis suggests that there may be greater variation in the morphological characters of S. unicorne than previously recognized, or that the Seiridium species from Oregon represents a hitherto unrecognized species. Previously reported analyses of pathogenic Seiridium species did not include isolates from North America, which appear more variable than isolates from Europe, New Zealand and Africa. The results of this study indicate that further analyses of Seiridium isolates from North America, including additional putative specimens from C. macrocarpa are needed to resolve this question. A number of challenges affected the success of inoculation testing procedures in this study. These included seasonal differences and variation in seedling diameter among inoculation groups. The results of this study provide a limited understanding of variation in susceptibility of Port-Orford-cedar families to natural populations of Seiridium due to the constraint of using a single Seiridium isolate, and should be interpreted accordingly. Despite these limitations, this study presents evidence for heritable variability in susceptibility within POC families to both cypress canker and Stigmina foliage blight, and suggests that there is high potential for improvement by selective breeding. The methods described in this thesis should be useful for future testing. Variation in susceptibility to these diseases should be considered in evaluating Phytophthora root disease resistance breeding efforts.
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This fifth annual Cooperative Pole Research Program report outlines our progress in the six project objectives. Improved Fumigants Sampling of previously established field tests revealed that Vorlex and ...
Citation Citation
- Title:
- Conserving energy by safe and environmentally acceptable practices in maintaining and procuring transmission poles for long service ; August 1985
- Author:
- Oregon State University, Oregon State University. Dept. of Forest Products
This fifth annual Cooperative Pole Research Program report outlines our progress in the six project objectives. Improved Fumigants Sampling of previously established field tests revealed that Vorlex and Chloropicrin continued to perform well after 15 years, while Vapam was slightly less effective. Solid methylisothiocyanate (MIT) also performed well in the field after 7 years. In additional tests, gelatin encapsulated MIT migrated through Douglas-fir heartwood with addition of moderate quantities of water to degrade the gelatin. However, in the presence of higher quantities of water or no additional water, MIT migration into the wood was slowed. In a previously established test, gelatin encapsulated MIT continues to inhibit reinfestation of poles 3 years after treatment. Pelletized MIT is a new formulation (65% active ingredient) that appears to have some promise. Preliminary tests indicate that up to 95% of the MIT is release in 24 hours, but a small quantity of MIT remains in the pellets after 63 days aeration and may pose a disposal hazard. The solid MIT formulations will permit aboveground applications, increasing the risk that MIT will come in contact with pole hardware. Preliminary tests indicate that MIT had little effect on corrosion of hot dipped, galvanized bolts attached to wood. This suggests that treatment in the crossarm zone with MIT or fumigants that produce MIT should not affect the integrity of attached hardware. i-i In addition to fumigant evaluations, we recently examined an earlier test of groundline treatments with Osmoplastic® and Hollowheart®. After 10 years, these treatments are performing reasonably well, with only a slight rise in the incidence of decay fungi in the past 4 years. We also reevaluated the effectiveness of kerfing for preventing decay and found that this process reduced the depth and width of checks, resulting in a decreased incidence of decay fungi. Kerfing appears to be a valuable method for preventing internal decay at the groundline. Cedar Sapwood Decay Control This past year, the second set of five chemicals applied to control sapwood decay were evaluated after 2 years of exposure. As in earlier evaluations using the Aspergillus bioassay, none of the chemicals approach pentachlorophenol in oil for ability to inhibit sporulation of Aspergillus niger; however, several samples from zones deep in the wood produced a slight zone of effect. This may indicate the presence of a reservoir for long-term protection against decay. Several of the chemicals including Fluor Chrome Arsenic Phenol and Ammoniacal Copper Arsenate (ACA) appear to bind to the wood and may be difficult to detect by the bioassay method. We expect to assess the effectiveness of these treatments using a soil block test. Investigations of the reliability of the Aspergillus bioassay under a variety of conditions indicated that quantity of spores, use of glass or plastic petri dishes, long-term cold storage, and the use of spray inoculum instead of flooding spores had little influence on the bioassay results with pentachiorophenol, Tributyl-tinoxide, or 3 iodo propynyl butylcarbamate; however, incubation temperature did influence assay results. The Aspergillus bioassay is a simple, effective means for estimating residual preservative levels. Bolt Holes Again this year, wood around the unprotected, control bolt holes in pole sections contained such low levels of decay fungi that evaluation of the treated poles will be delayed another year. In addition to the initial bolt hole treatments, we have begun a test to determine if gelatin encapsulated or pelletized MIT can prevent decay development in field-drilled bolt holes. The pole sections used in these tests had already begun to develop decay prior to treatment and will provide an ideal test material. Detecting Decay and Estimatin& Residual Strength of Poles Fluorescent labeled lectins used in our earlier studies detected decay fungi at low weight losses under laboratory conditions. We are currently evaluating this method for detecting fungi in increment cores removed from poles to reduce the need for culturing. Last year we identified a peak that was unique to infrared (IR) spectra of warm water extracts from decayed wood. This past year we attempted to identify the chemical responsible for this peak and found that carbonyl compounds, probably from oxidative lignin degradation, were responsible for the peak. Since brown rot fungi apparently do iv not completely metabolize lignin breakdown products, they accumulate in the decaying wood and can be readily detected by their IR spectra. Strength properties of beams cut front Douglas-fir pole sections, air-seasoned for 3 years significantly decreased although decay fungi could not be uniformly isolated from the beams. In addition, there were gradual declines in work to maximum load and modulus of elasticity, as well as increased Pilodyn pin penetration. These results suggest that some strength losses occurred during air-seasoning; however, the losses were not large and should not endanger pole users. We compared several test methods including the Pilodyn, radial compression tests, longitudinal compression tests, and the pick test for evaluating residual pole strength of the wood surface of Douglas-fir treated with combinations of funtigants or groundline wraps. The results indicate that only the pick test could accurately detect surface damage and illustrate the difficulty of detecting surface damage. This past year we evaluated several sections cut from ACA treated poles stored for a number of years to determine if they were worth salvaging. Static bending tests of beams cut from the ACA treated zone, the treated/untreated boundary, and the inner heartwood revealed ACA treated sapwood had lower MOR and longitudinal compression strength than the other zones. These results represent only a small sample, but they suggest that some strength loss occurs during ACA V treatments. More importantly, the results suggest that we could have reliably predicted beam MOR by testing small plugs removed from the poles. Small beams cut from decaying, pentachlorophenol treated Douglas-fir poles were acoustically tested for residual wood strength, then evaluated to failure in static bending. The acoustic test consisted of sending a pulsed sonic wave into the wood and recording this wave after it passed through the beam. As it moved, the wave was altered by the presence of any wood defects or decay, and these alterations create a "fingerprint" specific for that defect. Preliminary results indicated that signal analysis was highly 2 2 correlated with work to maximum load (r =.82) and MOR (r .88), suggesting that this approach to decay detection may prove more reliable than measuring of sound velocity. Initiation of Decay in Air-Seasoning Douglas-fir The results of the initial survey to determine the incidence of decay fungi in poles from widely scattered Pacific Northwest seasoning yards indicated that a variety of fungi were colonizing the wood. While most of these fungi do not pose a serious decay problem, two species, Poria carbonica and Poria placenta, became increasingly abundant with length of air-seasoning. These fungi are also the most conunon decayers of Douglas-fir poles in service. As expected, the number of fungi and the wood volume they occupied increased with seasoning time; however, this incidence varied considerably between yards, especially in poles air-seasoned for vi shorter time periods. In addition to the variation between sites, many of the decay fungi colonizing the wood appear to be monokaryons, indicating that spores landing on the wood are initiating the infestation. The distribution of fungi within the poles indicated that several of the more abundant decay fungi were present in the outer sapwood where they would be eliminated by conventional pressure treatment. The remaining fungi were most abundant in the heartwood but were more concentrated near the pole end. This suggests that exposed end grain was more readily invaded than lateral grain exposed in checks. In addition to identifying the fungi colonizing Douglas-fir, we examined the effects these fungi had on wood strength. Toughness tests indicated the presence of wide variation in decay capability of the isolates. Although there was no consistent pattern, most of the isolates did not cause substantial decay and, of those that did, only . carbonica and P. placenta were sufficiently abundant to have a large influence on wood strength. Due to the prevalence of P. carbonica and P. placenta in the inner heartwood, where they might not be eliminated in a short heating cycle, we evaluated the temperature tolerance of these two fungi in Douglas-fir heartwood blocks. These tests indicated that both fungi were eliminated by exposure to temperatures above 71°C for over 1 hour or 60°C for 2 hours. The results suggest that careful control of temperature during treatment should eliminate decay fungi and that wood treated at ambient temperatures should be heated to kill fungi that become established during air-seasoning. vii This past year was the third and final year of the decay development study. In this study, sterile pole sections have been exposed for 1, 2, or 3 years at widely scattered Pacific Northwest sites, then returned to the laboratory and extensively sampled. We are now in the process of identifying the fungi from the third year poles. In addition to examining poles prior to preservative treatment, we are also evaluating poles treated with waterborne chemicals (ACA or CCA) for the incidence of surface decay. This past year we examined twenty ACA-treated poles from a line installed in 1946. While a variety of fungi were cultured from the wood, none of the poles had evidence of substantial surface deterioration. A study was initiated on the fungal flora of fumigant treated wood because of the potential for fungi developing resistance to low levels of fumigant or the ability to actively degrade the chemical. Both of these developments could shorten fumigant retreatment cycles and increase maintenance costs. We have evaluated poles treated 7 and 15 years ago with fumigants and find markedly reduced fungal flora. Tests are continuing on the fungi isolated, and we hope to assess the effects of these isolates on long-term fumigant effectiveness.
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277. [Article] The historic and contemporary ecology of western Cascade meadows : archeology, vegetation, and macromoth ecology
Montane meadows in the western Cascades of Oregon occupy approximately 5% of the landscape, but contribute greatly to the region's biodiversity. Western Cascades meadows are dynamic parts of the landscape ...Citation Citation
- Title:
- The historic and contemporary ecology of western Cascade meadows : archeology, vegetation, and macromoth ecology
- Author:
- Highland, Steven A.
Montane meadows in the western Cascades of Oregon occupy approximately 5% of the landscape, but contribute greatly to the region's biodiversity. Western Cascades meadows are dynamic parts of the landscape and have contracted by over 50% in the past two hundred years in the HJ Andrews Experimental Forest (hereafter Andrews Forest). Many studies have linked the loss of meadows with local extirpation of species and loss of regional biodiversity, but these processes depend upon the factors that create and maintain meadows, and how species respond to meadow configuration. The prehistory of these meadows is poorly understood, as is the contemporary ecology. This study combined previously collected archeological and moth datasets, aerial photographs, and new plant, tree core, and moth data to investigate interactions between landforms, disturbance, vegetation, and moth abundance and diversity in montane meadows of the western Cascades of Oregon. Burning by prehistoric people may have created and maintained montane meadows, but relatively little evidence remains of the activities of prehistoric peoples in the western Cascades. This study assessed the extent to which prehistoric people preferentially used different landforms and vegetation types by inferring use from landscape distributions of archaeological sites. Descriptions of 359 previously recorded and four newly discovered archeological sites in the McKenzie River watershed of western Oregon were examined using GIS and chi-square analysis to determine how sites were distributed relative to classified vegetation and landforms of the 3700-km² McKenzie River watershed. The high ridges of the HJ Andrews Experimental Forest were analyzed using air photo change detection and archaeological field surveys to identify how archeological sites were distributed relative to landforms and vegetation communities, including meadows. The field surveys documented physical evidence (archeological sites) confirming Native American use of the meadows and surrounding open forests. The locations of these sites indicate that Native Americans utilized the edges between large open meadows and open forests, as well as gently sloping open meadows. The prior extent of meadows (before air photos) was estimated by dendrochronology of 220 trees along present-day and inferred past meadow edges. Forest age structure and the open-grown forms of Douglas fir suggests a much more open habitat, potentially due to fire, was present more than 200 years ago. Moths are major consumers of vegetation when in caterpillar stage and are food sources for many birds and mammals, and contribute greatly to the insect diversity in a region. Moth species richness and abundance may be associated with the distribution of vegetation communities and seasonal timing, and the conservation of rare moths may depend on the conservation of rare vegetation habitats. A dataset of moths sampled 10 times/year at 20 locations in the 64-km² Andrews Forest over the period 2004-2008 was analyzed using generalized linear mixed models (GLMM), non-metric multidimensional scaling (NMS), multi-response permutation procedure (MRPP), analysis of variance (ANOVA), and two tailed t-test to identify the overall patterns of rare and common moth distribution as well as moth community relationships to structurally and taxonomically derived vegetation classes and seasonality. Five hundred fourteen species and 69,168 macromoth individuals were identified. Moth species abundance and diversity were significantly higher in low elevation coniferous forests than in other vegetation types, according to the GLMM. Sixty-six rare moth species were significantly associated with high elevation open habitats. Species associated with meadows also were significantly more likely to be hardwood or herb-feeders than conifer-feeders as caterpillars, based on ANOVAs. The 26 most common moth species were significantly associated with low elevation coniferous forests and were more likely to be conifer-feeders as caterpillars, based on ANOVAs. Common moth species were significantly more likely to emerge earlier in warmer years than in cooler years, based on a two-tailed t-test. Managing the western Cascades landscape for moth biodiversity and for moth abundance requires maintenance and potentially expansion of rare upland habitats as well as lowland coniferous forests. Montane meadows in the Andrews Forest are contracting in size, but it is not known how these changes have affected moth and plant biodiversity. The rate and pattern of meadow contraction from 1949 to 2005 along the high ridges of the Andrews Forest were analyzed using air photo change detection. Overall meadows contracted by nearly 50% from 1949 to 2005, but rates of meadow loss were much higher for the largest meadow complexes. Plant community diversity in seventeen meadows and the diversity, abundance, and community structure of moths at 98 locations sampled in the summers of 2008, 2009, and 2010 were related to measures of meadow size, isolation, and other variables using cluster analysis (CLA), MRPP, NMS, and generalized additive models (GAMs). Plant diversity in meadows was significantly positively related to meadow area in 1949 and the distance of the meadow from the road, based on GAM analysis. Plant community structure was most closely correlated with meadow area in 1949 and slope, based on CLA, MRPP, and NMS analysis. Calendar day explained the most variation in moth species richness, abundance, and community structure, but the next most important explanatory variables differed according to feeding guild, based on GAMs. Richness, abundance, and community structure of herb-feeding moths was related to meadow area in 1949 and elevation. For angiosperm-feeding moths, area-perimeter ratio in 2005 explained the most variation in richness, abundance, and community structure after calendar day. For gymnosperm-feeding moths, meadow area change from 1949-2005, a variable measuring the amount of increase in coniferous tree cover, explained the most variation in richness, abundance, and community structure after calendar day. The abundance and diversity of herb-feeding moths and meadow plants exhibited a lagged response to habitat loss, which may indicate an extinction debt. In contrast, angiosperm-and gymnosperm-feeding moths responded quickly (within 50 years) to increases in their habitat. Managing for the conservation of biodiversity in the upper elevations of the Andrews Forest will require targeted management strategies for different groups of organisms. Herb-feeding moths and meadow plants will benefit from expansion of open meadow habitat, while angiosperm and gymnosperm-feeders will require the maintenance of edge environments and coniferous forests.
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278. [Article] Mosby Creek Limiting Factors Analysis and Restoration Plan
Abstract -- The Mosby Creek Limiting Factors Analysis (Rapid Bio-Assessment) assessed stream conditions for native salmonids and prioritized projects of benefit to spring Chinook, cutthroat trout, rainbow ...Citation Citation
- Title:
- Mosby Creek Limiting Factors Analysis and Restoration Plan
Abstract -- The Mosby Creek Limiting Factors Analysis (Rapid Bio-Assessment) assessed stream conditions for native salmonids and prioritized projects of benefit to spring Chinook, cutthroat trout, rainbow trout, and Pacific lamprey in this high-priority, free-flowing stream in the Coast Fork Willamette Watershed. To gain access to private properties adjacent to the 75 miles of surveyed streams, the applicant conducted landowner outreach and coordinated two years of continuous temperature data collection by volunteers. The contractor conducted a modified limiting factors analysis and a snorkel survey in the Mosby Creek main stem and tributaries up to 6 percent gradient. The resulting study results include a prioritized restoration plan that has been shared with local landowners and restoration partners and used for restoration planning.
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279. [Article] Effects of riparian buffer width on wood loading in headwater streams after repeated forest thinning
To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...Citation Citation
- Title:
- Effects of riparian buffer width on wood loading in headwater streams after repeated forest thinning
- Author:
- Burton, Julia I., Puettmann, Klaus J., Olson, Deanna H.
To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.aanda.org/
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280. [Article] Influence of vegetation on streambank hydraulics
Proper use of vegetation in streambank bioengineering practices requires a comprehensive understanding of the influence of vegetation density on streambank hydraulics. A series of studies were conducted ...Citation Citation
- Title:
- Influence of vegetation on streambank hydraulics
- Author:
- Czarnomski, Nicole M.
Proper use of vegetation in streambank bioengineering practices requires a comprehensive understanding of the influence of vegetation density on streambank hydraulics. A series of studies were conducted to investigate the relationship between independent variables vegetation density, bank angle, and discharge and dependent variables channel velocity, resistance, turbulence, and shear stress. Flume experiments were conducted varying vegetation stem density (number of plants/horizontal area) and frontal area (number of leaves/vertical area) on 30° and 15° vegetated bank-toes at three discharge rates. Three sets of 3D velocity measures were collected using an ADV at: 1) 0.6 x depth, 2) near-boundary, and 3) velocity profiles. Resistance parameters for drag coefficient (C[subscript d]) and Manning's n were estimated. Turbulent stress measures based on turbulent kinetic energy and Reynolds stress were used to evaluate boundary shear stress. Tensor fields were visualized to explore vorticity and near-boundary hydraulics. Results demonstrated that as vegetation density increased, water was increasingly redirected from the bank-toe to the main channel, decreasing downstream velocity along the bank-toe by 35-95% and increasing downstream velocity in the main channel by 80-240%. As vegetation density increased and water velocity decreased along the bank-toe, depths increased, surface slope flattened, and an eddy formed downstream of the vegetated patch. C[subscript d] increased with increasing vegetation density, and decreasing stem Reynolds number. Estimates of C[subscript d] and n were high relative to commonly published values, especially when vegetation density was high. Increasing vegetation density also increased turbulence and shear stress, creating greater opportunity for erosion at sensitive locations along the bottom of the bank-toe and in the main channel. Reynolds stresses also increased under the canopy, resulting in higher shearing forces along the bank-toe, especially on the 30° bank-toe. Differences in results between bank-toe angles were minimal, dominated by the influence of vegetation. Magnitude of results decreased with decreasing discharge, but patterns were similar. Findings suggest planting at higher densities may protect the bank from erosion, but may increase the potential for erosion along the interface between the bank and main channel if unprotected, though further research with natural plant communities is encouraged to confirm findings.