Dissertations / Theses: 'Forestry Sciences'

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Makano, Rosemary Fumpa. "Does institutional capacity matter? a case study of the Zambian Forestry Department /." Diss., St. Louis, Mo. : University of Missouri--St. Louis, 2008. http://etd.umsl.edu/r3321.

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Ostovar, Ahmad. "Enhancing Forestry Object Detectionusing Multiple Features." Thesis, Umeå universitet, Institutionen för datavetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-93528.

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In this Master's project increasing the performance of object detection inforestry environment, based on the extracted features is studied. There areseveral object detection projects for robots which are based on feature cal-culation and extraction. An example of these kinds of projects is the sugarbeet project [3] that has inspired the feature selection and calculations partspresented in this report. Extracted feature sets are given to several classiersand their results are merged and fused such that the overall performance ofthe forestry object detection increases. Furthermore dierent supervised andunsupervised methods of dimensionality reduction are applied on the featureset as an approach to improve classication accuracy. Comparison betweenthe output classication performance of dimensionality reduction methodsshow that applying supervised methods result in improving the classicationperformance by about 12 percent.

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Lorz, Carsten, and Martin Heckner. "The training forest trail of the Department of Forestry, Hochschule Weihenstephan-Triesdorf, University of Applied Sciences, Germany." Technische Universität Dresden, 2019. https://tud.qucosa.de/id/qucosa%3A34337.

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As part of the programme BA Forest Engineering at Hochschule WeihenstephanTriesdorf, University of Applied Sciences (HSWT), Department of Forestry we introduced a Forest Training Trail (FTT) to complement our curriculum with a strong focus on applied training in the field. The core of the FTT is (i) the trail itself with several sites with different focus and (ii) a questionnaire. Every semester a new trail at a new site within the training forest is set up. Usually, the trail encompasses four to six stations, each station representing a thematic focus of the training in the BA 'Forest Engineering', e.g. vegetation, silviculture, hunting, environmental protection, soil or other aspects. The students form teams of three and walk the FTT with a questionnaire and a map of the trail. After the deadline for handing in the questionnaires a master solution of the FTT is published on the faculty homepage in order to give students an opportunity for a self-feedback. The results of the regular evaluation show a high acceptance by the students. Our conclusion after four years of experience with the FTT is that the design as competition and game including a trophy resulted in a very high acceptance and participation with joy.

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Strandberg, Tora. "Inventorying humans in the forest : a study of coastal forest owners'understanding of the political shift in focus within Swedish forestry." Thesis, Linköping University, Department of Thematic Studies, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1950.

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Forestry operations in Sweden can be traced a long way back in history. The overall emphasis has traditionally been on the forests’ economic or profitable role, even though they are also of great ecological and social interests. Nevertheless, the focus has shifted during the last decade due to the impact of sustainable development. A new Forestry Act has now provided the Swedish forestry with a new policy which is guided by two equally-weighted objectives; production and environmental concern. The European Union (EU) has also adapted to the direction of sustainable development. It places particular interest in the creation of sustainable coastal areas within the union.

The aim of the Bachelor of Science thesis was to investigate how Swedish coastal forest owners define their role in the creation of sustainable coastal forests. The study is built on interviews which were conducted with seven forest owners, all of whom have properties in the coastal zones of Östergötland and Kalmar. These two counties are situated in the south-eastern part of Sweden.

The study raises three different issues. The first is the manner in which the informants shape their knowledge of the existing forestry legislation, based on their identities and responsibilities. The second concerns the preconditions with which they are faced when managing their coastal forest properties and whether or not they see the new legislation as a shift in focus. The final issue highlights the importance of local knowledge and looks at the participation of the informants in the development of new regulations.

The following conclusions are drawn from the investigations. Many owners of forest properties do not identify themselves as forest owners; it is therefore important to be aware of this distinction which is made between being a forest owner and being the holder of a forest property. The coastal forest owners who were interviewed run their forests according to their individual situations. Because of this they do not appear to be part of any shift of focus within the Swedish forestry. As a result, they may not have a defined role in its development. This role would probably be clearer or greater if their local knowledge were more explicitly valuated.

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Schmidt, Pieter, Siegfried Lewark, Jiří Remeš, and Norbert Weber. "Forests for University Education: Examples and Experiences: Proceedings of the SILVA Network Conference, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague." Technische Universität Dresden, 2019. https://tud.qucosa.de/id/qucosa%3A33621.

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Forests play a crucial role in preserving terrestrial biodiversity, producing renewable raw materials, and in reducing the scale and impact of climate change. Proper forest management is therefore crucial for today's society. For these reasons, forestry education is no less important because its aim is to educate highly qualified professionals capable of meeting current challenges. Forestry education has already had a relatively rich history, in many European countries over 100, even 200 years. A very important role in forestry education has always been played by the forest itself, which has been the place of teaching and the largest research laboratory. However, given the rapid advances in science and technology development, it is necessary to redefine the place and importance of the forest for university forestry education at present.

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Duveneck, Matthew Joshua. "Managing for Resistance and Resilience of Northern Great Lakes Forests to the Effects of Climate Change." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1551.

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Climate change is expected to drastically change the environmental conditions which forests depend. Lags in tree species movements will likely be outpaced by a more rapidly changing climate. This may result in species extirpation, a change in forest structure, and a decline in resistance and resilience (i.e., the ability to persist and recover from external perturbations, respectively). In the northern Great Lakes region of North America, an ecotone exists along the boreal-temperate transition zone where large changes in species composition exist across a climate gradient. Increasing temperatures are observed in the more southern landscapes. As climate change is expected to substantially affect mid-continental landscapes, this region is especially vulnerable to climate change. My research assessed the effects of climate change under business as usual (BAU) management as well as alternative management strategies. To do so, I simulated forest change in two landscapes (northeastern Minnesota and northern lower Michigan) under three climate change scenarios (current climate, low emissions, and high emissions), and four management scenarios (BAU, modified silviculture, expanded reserves, and climate suitable planting) with a spatially-explicit forest simulation model from year 2000 to year 2150. Specifically, I explored how climate change would affect relationships between tree species diversity and productivity; how expanded reserves and modified silviculture may affect aboveground biomass (AGB) and species diversity; how climate suitable planting may affect functional diversity, and AGB; and how alternative management may affect the resistance and resilience of forests to multiple disturbances interacting with climate change. Under the BAU management scenario, I found that current and low emissions climate scenarios did not affect the relationship between species diversity and productivity; however, under a high emissions climate scenario, a decline in simulated productivity was coupled with a stronger positive relationship between diversity and productivity. Under the high emissions climate scenario, overall productivity declined in both landscapes with specific species declines projected for boreal species such as balsam fir (Abies balsamea) and black spruce (Picea mariana). Under alternative management scenarios, I simulated a limited ability to increase tree species and functional diversity, AGB, and net primary productivity under climate change. The limits of management were especially apparent under the high emissions climate scenario. In a novel approach to measuring resilience, I plotted the recovery of both initial species composition and AGB to stochastic fire events for each simulation. This approach assessed both a general response (i.e. AGB) with a more specific response (i.e. species composition). My results suggest that climate change will reduce the resilience of northern Great Lake forest AGB and species composition and that management effects will be largely outweighed by the declines expected due to climate change. My results highlight the necessity to consider even more innovative and creative solutions under climate change (e.g., planting species from even further south than I simulated).

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White, Russell Alan. "Accuracy of Forest Road and Stream Channel Characteristics Derived from LiDAR in Forested Mountain Conditions." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/251.

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Forest roads and stream channels are mapped using a variety of remote sensing and ground-based techniques. In densely forested areas, conventional remote sensing methods provide limited terrain information, while ground-based surveys can be time-consuming, difficult, and expensive. Light Detection and Ranging (LiDAR) is an airborne remote sensing technology used to create high-resolution digital elevation models (DEMs) of the earth’s surface. This study tests the accuracy of forest road and stream channel features mapped using LiDAR in the steep, forested terrain of California’s Santa Cruz Mountains. A conventional total station survey was used to determine centerline position and elevations along a four-kilometer forest road, and along six thirty-meter stream channel study reaches. A 1.5 m LiDAR DEM was suitable to accurately map the location of the forest road and channel features. Ninety five percent of the LiDAR-derived road length was located within 2.2 m normal to the field-surveyed centerline and LiDAR-derived road slopes were not significantly different from field-surveyed slopes. Stream channel features derived from the LIDAR DEM were located within 2.7 m normal to the field-surveyed thalweg, while the LiDAR-derived slopes measured within 0.49 percent of field-surveyed slopes. These findings indicate that LiDAR can provide accurate terrain measurements that are suitable for resource management and assessment.

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Bång, Filip. "Computer vision as a tool for forestry." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-85214.

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Forestry is a large industry in Sweden and methods have been developed to try to optimize the processes in the business. Yet computer vision has not been used to a large extent despite other industries using computer vision with success. Computer vision is a sub area of machine learning and has become popular thanks to advancements in the field of machine learning. This project plans to investigate how some of the architectures used in computer vision perform when applied in the context of forestry. In this project four architectures were selected that have previously proven to perform well on a general dataset. These four architectures were configured to continue to train on trees and other objects in the forest. The trained architectures were tested by measuring frames per second (FPS) when performing object detection on a video and mean average precision (mAP) which is a measure of how well a trained architecture detects objects. The fastest one was an architecture using a Single Shot Detector together with MobileNet v2 as a base network achieving 29 FPS. The one with the best accuracy was using Faster R-CNN and Inception Resnet as a base network achieving 0.119 mAP on the test set. The overall bad mAP for the trained architectures resulted in that none of the architectures were considered to be useful in a real world scenario as is. Suggestions on how to improve the mAP is focused on improvements on the dataset.

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DeRose, R. Justin. "Disturbance Ecology and Vegetation Dynamics at Varying Spatial and Temporal Scales in Southern Rocky Mountain Engelmann Spruce Forests." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/516.

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High-severity disturbances are the primary drivers of Engelmann spruce-subalpine fir ecosystems in the southern Rocky Mountain. Recently, an unprecedented, landscape-wide (at least 250 km2) spruce beetle outbreak killed virtually all the Engelmann spruce on the Markagunt Plateau in southwestern Utah, USA. Results from dendroecological analyses suggested the combination of antecedent disturbance history and drought-driven stand development was responsible for creating suitable host conditions prior to the recent outbreak. Multiple and consistent lines of evidence suggested mixed- and high-severity fires shaped the development of the Markagunt Plateau. Subsequent stand development, influenced by species-specific differential tree-ring response to drought, resulted in the gradual increase of Engelmann spruce dominance across the landscape. Spatiotemporal outbreak dynamics included the early, independent and spatially synchronous building of beetle populations in moist sites with large Engelmann spruce across the landscape. As the outbreak evolved over time, it is likely temperature anomalies accelerated beetle population growth, leading to more rapid spruce mortality. In the wake of the spruce beetle outbreak, results from simulated potential fire behavior suggested there was a reduction in probability of active crown fire for one or two decades on near-pure Engelmann spruce sites after the outbreak. This counterintuitive result suggested extreme fire behavior is not an inevitable consequence of spruce beetle outbreaks. Regardless of the occurrence of fire, forest response is likely to be dominated by advance regeneration in the seedling bank. Furthermore, because spruce was virtually absent from the understory, forest reorganization is likely to be dominated by subalpine fir. In response to recent outbreaks such as the Markagunt Plateau, silviculturists are questioning what they can do to limit the loss from these likely inevitable spruce beetle outbreaks. Concepts of resistance and resilience can be used in planning vegetation management intended to indirectly control beetle populations by manipulating their habitat (vegetation). Resilient landscapes will ideally have spruce age class diversity and size class diversity in spatially discontinuous patches.

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Filgueira, Amorim Franca Tamara Suely. "Southern Yellow Pine In-Grade Lumber Evaluation." Thesis, Mississippi State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10289581.

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The southern pine species group is the main softwood resource used in the U.S, and the majority of southern pine is used in lumber production. The use of lumber in structural purpose requires feasible strength and stiffness grading method ensuring characteristics allowable stress values. The stiffness and strength of most of southern pine lumber is assessed using visual grading system. The objective of this study was to evaluate a production weighted sample of 2 × 4, 2 × 6, 2 × 8, and 2 × 10 No. 2 grade southern pine lumber collected across its geographic range. The results of this research show a snapshot of the material commercially sold in the southern U.S. region. Over one third of the specimens contained pith, and had an average mean value of 4.6 for number of rings per inch (RPI) and 43.8% for latewood (LW). The overall specific gravity (SG), modulus of elasticity (MOE) and modulus of rupture (MOR) were 0.54, 10.1 GPa, and 41.7 MPa, respectively. The allowable design bending strength (F_b) for 2 × 4, 2 × 6, 2 × 8, and 2 × 10 was 11.2, 9.2, 8.1, and 7.1 MPa, respectively. Specimens containing no pith, RPI higher or equal then 4.0, and LW higher or equal then 33.0% were greater in MOE and MOR. The effect of grading controlling characteristics of the material was also studied. The presence of knots had the most significant impact on mechanical properties. Specimens with wane and shake had greater SG, MOE, MOR, F_b values than specimens with others grading controlling characteristics. The mean values found for RPI, LW, and SG met the requirements recommended for southern pine No. 2 lumber. The MOE and F_b values found therein met the previous and the new allowable design value. The results of this research can be used to identify and to select the best variables to improve the prediction of bending properties of visually graded lumber.

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Aslezaeim, Nasrin. "Effect of cultural intensity and planting density on wood properties of loblolly pine (Pinus taeda L.)." Thesis, Mississippi State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10141637.

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The effects of cultural intensity (operational and intensive) and planting densities (741, 1483, 2224, and 2965 ha^-1) on modulus of elasticity (MOE), modulus of rupture (MOR) and specific gravity (SG) of small clear samples obtained from 15 and 16 year-old loblolly pine ( Pinus taeda) from the Lower Coastal Plain and Piedmont region of the southeastern United State were examined. Planting density and distance from pith showed a significant (p < 0.0001) and strong main effect on stiffness (MOE) and strength (MOR) for the samples. Regardless of planting density, MOE, MOR and SG of samples increased significantly from pith toward bark. A significant culture × density interaction ( p < 0.0001) was observed for the samples obtained from the Lower Coastal Plain.

The project also determined the feasibility of measuring microfibril angle (MFA) on solid wood loblolly pine samples using scanning electron microscopy and transmission electron microscopy with the angle analyzed using image analysis. Measurements of MFA revealed minor differences (5⁰) between juvenile wood and mature wood.

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Davis, Ryan Stephen. "Ponderosa Pine Mortality and Bark Beetle-Host Dynamics Following Prescribed and Wildland Fires in the Northern Rocky Mountains, USA." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/44.

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Ponderosa pine delayed mortality, and bark beetle attacks and emergence were monitored on 459 trees for 3 years following one prescribed fire in Idaho and one wildland fire in Montana. Resin flow volume (ml) was measured on 145 fire-injured ponderosa pine 2 and 3 years post-fire. Logistic regression was used to construct two predictive ponderosa pine mortality models, and two predictive bark beetle-attack models. Post-fire delayed tree mortality was greater with the presence of primary bark beetles independent of diameter at breast height (DBH) (cm), and was greater in smaller diameter trees most likely due to direct effects of fire-caused injuries; mortality was lower in trees with less percent bud kill (PBK). The frequency of bark beetle attack was greater in trees with less percent bud kill and greater bole char height proportion (CHIP). Attack frequency was also greater on trees with higher percent bud kill and greater diameter at breast height. Classification tables for all predictive models were presented for application in post-fire management development. Multivariate ANOVA analyses were used to describe the effects of morphological and fire-injury variables on ponderosa pine resin production, and bark beetle attack preference and emergence. Resin production (ml) was significantly greater on burned than unburned trees. Resin flow increased significantly between June and July 1 year following fire and from June to August 2 years following fire. Resin flow was lower on the north bole aspect than the south and west aspects of unburned trees. Resin flow of burned trees significantly increased through the summer and was greatest in trees with high pre-fire live crown length (m) (LCL). Resin flow of unburned trees differed significantly by year, month, bole aspect, and live crown length. Resin increased by month and live crown length, decreased from 2005 to 2006, and was less on the northern bole aspect than all other aspects. Bark beetles preferred to attack fire-injured trees, especially within bole-scorched areas. No significant differences in bark beetle emergence were found between fire-injured and non fire-injured trees. On burned sites, beetle emergence was greatest from larger diameter trees with less severe fire injury. Western pine beetle (Dendroctonus brevicomis LeConte) had the greatest emergence from fire-injured ponderosa pine, and Ips pini (Say) had significantly greater emergence from non fire-injured ponderosa pine.

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Bremer, Edith. "The effects of forestry on stream ecological integrity." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-160127.

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This study investigates the effects of forestry on leaf litter decomposition in small forest streams. Riparian forest, that is the land closest to the stream, maintain shading, water temperature and energy supply through litter fall. If the riparian zone is deforested, many riparian functions important for the integrity of the stream ecology, hydrology and biogeochemistry can be lost or modified. Leaf litter decomposition can be used as an integrated measure of the physical and biological changes following forestry perturbations. This study was conducted in 11 northern and 12 southern Swedish streams to address; 1) How is leaf litter decomposition in small streams affected by forestry by measuring leaf litter decomposition in streams with different buffer widths, and; 2) How other environmental variables, such as stream bottom substrate, canopy openness, water temperature and stream velocity affected leaf litter decomposition. Buffer width had no effect on decomposition. Temperature and proportion organic bottom substrate had respectively positive and negative trends with decomposition in the southern Swedish sites which suggests the importance of forestry targeting these riparian functions especially when managing small streams. At the northern sites, velocity showed a positive, and temperature a negative trend with leaf litter decomposition but none of these were significant. It is possible that the extraordinarily warm and dry weather before and during the study was conducted affected aquatic organisms to the degree that decomposition was inhibited, and most trends became too small to detect or that buffer width is less important in a warmer climate.

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Farnung, Caitlin M. "Understanding the Challenges of Expanding Community Forestry in Northwest Cameroon." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2011.

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The tropical afro-montane forest of the Northwest region is unique and under direct threat from the high population density of the region. Community-based forestry management is an opportunity to sustainably manage the remaining forest fragments. Community forestry was introduced to Cameroon with the legislation of the 1994 Forestry Law. Over two decades later little research has been conducted in the Northwest region of Cameroon. Twenty-four semi-structured interviews were conducted, and samples of forestry records were analyzed as exploratory research that would act as a base for further research. This research found that the tenure of the community over the community forest needed to be strengthened, marginalized populations needed to be empowered to participate, and governance needed to be improved both nationally, and locally. Further research will strengthen these conclusions and help Cameroon, and community forests around the world, be effectively established and managed.

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Winter, Cody R. "Perceptions Affecting Tree Valuation: An Analysis of Recently Sold and Leased Properties in Tampa, Florida." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7110.

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The urban forest is a structure that is fluid in both species composition and how it is integrated in our cities and suburban areas. Much like the fluidity in its structure, the urban forest provides ecosystem services and disservices in many forms. These services and disservices can often come in the form of temperature regulation, lower crime rates, and even higher property values. The latter, which is associated with the economic value of trees, is a part of the hedonic pricing literature which suggests that there is a disparity in the value associated with trees to house prices. With the City of Tampa conducting its own hedonic pricing study, along with the presence of robust urban forest data, 2,000 residents of the city who had recently purchased or rented their home were mailed a questionnaire gauging how trees influenced their decision to live at their current residence and how they perceived the urban forest. Out of the 2,000 properties, 400 of the surveys were received resulting in a 20% return rate. Five hypotheses were tested to determine how people’s perceptions affected the value they place on trees. It was hypothesized that home owners were more likely than renters to report tree disservices due to high maintenance costs, and potential damage. Additionally, it was hypothesized that homeowners would likely report more negative opinions of trees compared to renters. The analysis showed that tree drawbacks related to cost/maintenance and damage were reported by 43% and 45% of homeowners respectively. Likewise, 32% of renters reported cost/maintenance and 37% reported damage as their top drawbacks of trees. Although homeowners more frequently reported cost/maintenance and damage as drawbacks of trees, there was no significant statistical difference in opinion on trees at the .05 level. It was hypothesized that because neighborhood trees have less drawbacks such as property damage, residents would favor neighborhood trees more than trees on their property. Cross tabulating Likert statements with canopy cover did not reveal a preference for neighborhood trees above trees found directly on resident property. It was hypothesized that respondents living in homes with lower assessed values would express more negative opinions of trees such as cost and maintenance being reported as drawbacks. Cross tabulating sales price with the negative Likert statements concerning trees revealed that homes with higher assessed value reported more negative opinions of trees. It was hypothesized that different ethnic groups such as African Americans, Hispanic/Latinos, and White/Caucasians as well as residents of different affluence would report similar opinions and tree cover percentages with people from similar demographics. Despite the current literature suggesting differences in opinions, preferences, and canopy cover for different races/ethnicities, the analysis did not reveal a link between race/ethnicity and the availability of tree canopy or landscape preference. Finally, it was hypothesized that there would be a high correlation between residents’ purchases and/or rental decisions and the extent of canopy cover from trees originating on their property and/or in their neighborhood. For respondents who strongly agreed/agreed that trees influenced their rental/purchase decision there was a marginally higher canopy cover in the area surrounding their property than directly on their property. Additionally, there appeared to be no relationship with the level of agreement that trees influenced residents’ decision to rent/purchase and the amount of tree canopy on their property and in their neighborhood. The conclusions of the study are that the opinions of trees in Tampa, FL are primarily positive among those in the sample population. In order to gain less biased results it is suggested that a door to door method be utilized in the future. It is also suggested that residents’ opinions are sampled after a severe storm to assess how hazardous conditions affect the overall opinions surrounding trees.

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Orefice, Joseph N. "Silvopasture in the Northeastern United States." Thesis, University of New Hampshire, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3708463.

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Silvopasture, the sustainable integration of livestock and trees on the same unit of land, may have the potential to contribute to agricultural productivity in the Northeastern United States and concurrently encourage the ecosystems services which trees provide. Extremely little is known regarding the ecological characteristics of silvopastures being utilized, their social and economic drivers, or their agricultural productivity. Silvopasture characteristics, management, and reasons for use were documented through a purposeful sample of silvopasture practitioners in New York and New England. Results document the functional role of silvopastures on regional farms. This research also investigated the ecological and production dynamics of silvopastures in the Northeastern United States, their management, and the reasons for their use. Forest conversion to silvopasture, open pasture, and heavily thinned forests were utilized to investigate the ecological and production dynamics during the establishment phase of forest conversion to pasture. Results suggest the potential for silvopasture as a competitive management option for forestland. This dissertation establishes a baseline for future investigations into the management of silvopastures in the Northeastern United States.

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Syslo, John Michael. "Dynamics of Yellowstone cutthroat trout and lake trout in the Yellowstone Lake ecosystem| A case study for the ecology and management of non-native fishes." Thesis, Montana State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3708793.

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The introduction of lake trout Salvelinus namaycush into Yellowstone Lake preceded the collapse of the native Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri population. As a system with a simple fish assemblage and several long-term data sets, Yellowstone Lake provided a unique opportunity to evaluate the ecology of a native salmonid in the presence of a non-native salmonid population undergoing suppression in a large natural lake. Diet data for Yellowstone cutthroat trout and lake trout were evaluated at varying densities to determine the effects of density on diet composition. Temporal diet shifts from 1996-1999 to 2011-2013 were likely caused by limitation of prey fish for lake trout. Diets, stable isotopes, and depth-related patterns in CPUE indicated lake trout > 300 mm consumed primarily amphipods, making them trophically similar to Yellowstone cutthroat trout from during 2011-2013. A lake trout removal program was initiated during 1995 to reduce predation on Yellowstone cutthroat trout. Abundance and fishing mortality were estimated for lake trout from 1998 through 2013 and Yellowstone cutthroat trout from 1986 through 2013. Density-dependence was evaluated by examining individual growth, weight, maturity, and pre-recruit survival as a function of abundance. In addition, a simulation model was developed for the lake trout-Yellowstone cutthroat trout system to determine the probability of Yellowstone cutthroat trout abundance persisting at performance metrics given potential reductions in lake trout abundance. Estimates of Yellowstone cutthroat trout abundance varied 5-fold and lake trout abundance varied 6-fold. Yellowstone cutthroat trout weight and pre-recruit survival decreased with increasing Yellowstone cutthroat trout abundance; however, individual growth and maturity were not related to abundance. Lake trout population metrics did not vary with lake trout abundance. Simulation model results were variable because of uncertainty in lake trout pre-recruit survival. Conservative estimates for required lake trout reductions were > 97% of 2013 abundance for a > 70% probability of Yellowstone cutthroat trout persistence at the performance metrics outlined in the Native Fish Conservation Plan. Lake trout removal will likely reduce lake trout abundance and result in Yellowstone cutthroat trout recovery if the amount of fishing effort exerted in 2013 is maintained for at least 15 years.

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Irons, Andrea M. "Riparian forest dynamics along the Sacramento River, California| Constructing tree age models to illustrate successional patterns." Thesis, State University of New York Col. of Environmental Science & Forestry, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10245526.

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Though land conversion and flow alteration have heavily impacted the Sacramento River riparian ecosystem, restoration opportunities still exist in the hydrogeomorphically active Middle Reach. This study of riparian forest succession focused on six dominant riparian tree species to explore relative establishment timing and the potential impacts of altered flow regimes. We utilized tree inventory data and increment cores collected from riparian forest stands to establish a temporal chronosequence of floodplain surfaces and associated tree ages and colonization timing. Tree age calculations incorporated raw ring counts and sampling error simulations. Results were then used to construct species-specific, diameterage models and predict age distributions for all inventoried trees. Cottonwood’s colonization window was longer than expected (up to 95 years after floodplain creation), whereas box elder and walnuts established on floodplains <50 years old. This study lays the groundwork for future research into the health and development of the Middle Reach riparian forest.

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Seliske, Patrick. "Forestry pesticide spraying and cancer incidence in New Brunswick : an ecological study." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74248.

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The human health risk associated with exposure to pesticide formulations applied to New Brunswick forests was examined for 31 sites of cancer, using measures of exposure based on the proximity of non-city population centers to spray areas.
Two organochlorine and two organophosphate exposure indices were developed by using maps of areas sprayed each year during the period 1952 to 1976. These data were analyzed in relation to cancer incidence rates during the period 1977-l980 for 254 New Brunswick municipalities.
Follow-up case-control studies of the cancer sites considered does not seem to be a matter of high priority at present. However, continued surveillance and data analysis involving more recent data is needed, particularly in the case of organophosphate formulations, due to the relatively short interval between exposure and outcome ascertainment for this exposure.

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Deane, McKenna Daniel C. "Managing for Multiple Objectives in Southwestern Forests: Evaluating the Trade-offs between Enhancing Mexican Spotted Owl Nest Habitat and Mitigating Potential Crown Fire." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/6878.

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The Forest Inventory and Analysis (FIA), the United States’ forest census, measured sixty-six Mexican spotted owl nest stands in order gain insight into the structure and composition of the nest habitat of this threatened species. I used these data, along with the greater FIA database and the Forest Vegetation Simulator to explore questions surrounding the management of Mexican spotted owl habitat, specifically how to balance the objective of sustaining and enhancing nest habitat in face of increasing forest fire size and severity in the Southwest. My research consisted of three studies. The first study quantified the structure and composition of the Mexican spotted owl nest stands and scrutinized current evaluation criteria of nest habitat. The second study estimated how much of the Southwestern landscape is at risk to high-severity crown fire and how much of the landscape is suitable Mexican spotted owl nest habitat. The third study modeled forest dynamics and silvicultural intervention in potential Mexican spotted owl nest stands. The purpose of this research is to assist in management of Southwestern forests in order to decrease fire size and severity while sustaining and enhancing current and future Mexican spotted owl nest habitat.

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Dement, Wesley T. "AN INVESTIGATION OF TREE GROWTH AND WOODY VEGETATION COLONIZATION ON A 19 YEAR-OLD FORESTRY RECLAMATION SITE." UKnowledge, 2017. https://uknowledge.uky.edu/forestry_etds/37.

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Survival, growth and biomass accumulation of 19 year-old trees planted on an Appalachian surface mine site were evaluated to determine the effect of spoil grading and surface amendment treatments. Three spoil grading treatments (loose-dump, strike-off and graded control) were established to create a range of operationally feasible spoil compaction capable of impacting tree establishment and growth. Likewise, three surface amendment treatments (straw/manure mulch, hardwood bark mulch and control) were applied to determine their effects on tree development. Trees grown under low-compaction grading treatment levels (strike-off and loose-dump) consistently outperformed trees planted in a high-compaction control treatment. Loose-dump preparation resulted in higher survival for five of six tree species and greater biomass in three species for which this metric was estimated. Strike-off preparation resulted in higher diameter at breast height (DBH) values. The addition of straw/manure surface amendment increased biomass for hardwood species for which this value was estimated. Volunteer woody vegetation growing in the same experimental plots was measured and characterized by species. Loose-dump plots exhibited highest overall volunteer stem and native stem density and compacted control plots had lowest volunteer stem density and lowest proportion of native stems. Strike-off plots exhibited intermediate values for both of these measures.

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Bragg, Hope A. "Attitudes and Roles of Women and Minorities in Community and Urban Forestry Professions." DigitalCommons@USU, 1998. https://digitalcommons.usu.edu/etd/7424.

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Community and urban forestry is a multifaceted field ranging from tree planting to removal, hazard assessment, and public relations. However, the racial and gender diversity of the community forestry workforce is remarkably low. To gain a better understanding of this lack of diversity, I surveyed professionals in two major community/urban forestry organizations. Age, income, and years in the profession were considered, along with education level, to determine if there is some underlying reason for low representation of women and minorities in the community/urban forestry field. I found that while white males dominated all work sectors (especially private organizations), women were concentrated in public or non-profit organizations holding positions in offices, education, or other jobs with extensive public interaction. Minorities held similar positions to women or were in entry level jobs and general tree care rather than in more professionally advanced positions. Attitudes regarding most aspects of the profession varied little based on sex or minority status, with only minor differences on advancement potential and salary.

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23

Swantek, Pamela Jane 1972. "Development of a database to analyze historical fire activity in southern Arizona: A prototype from Saguaro National Park." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/278630.

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With Anglo settlement of southern Arizona in the late 1800s, fire regimes were altered dramatically. Currently, desert scrub has experienced a dramatic rise in frequency and size of wildfire which may remove fire-intolerant perennials that define the community structure. On the contrary, woodlands and forests now contain excessive fuel build up and require prescribed burning to restore the system's balance. These opposing attitudes reflect the conundrum of how to manage naturally occurring fires, or where and when to initiate prescribed burning to recreate each vegetation community's "natural" fire regime. To resolve this dilemma, there is need to discern natural fire histories by collecting specific baseline data such as where, when and how the landscape has burned. This research has been focused on the design and development of a relational database, and the incorporation of a geographic information system to develop a system that can be used to fulfill this need.

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24

Hoffman, Deborah L. "Community-based sustainable forest managment: A case study of Rutland Township, Ohio." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1137583291.

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Suwarno, Yogi. "Responding to climate change : policy integration and the Indonesian forestry sector." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7694/.

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Literature on the integration of cross-cutting issues, or policy integration, has given little attention to how policy-making processes allow for policy integration as well as present barriers. There is also little evidence of how sectoral ministries respond to crosscutting issues and in what way they are affected by pressure to address such issues, including those promoted by ‘competing’ agencies. Climate change presents a significant and important issue for integration into many areas of public policy. Many government ministries and departments are tasked with responding to climate change mitigation and adaptation objectives. Forestry is a key sector in building a response to climate change and so an investigation into how policy-makers and policy-making processes have responded to climate change can shed light on the integration of cross-cutting issues. The thesis reports on investigation into how the Ministry of Forestry, Indonesia, has responded to climate change and into the organisational arrangements developed in the response to climate change. The research developed an innovative framework for the analysis of policy integration, generating conclusions in relation to the policy process, organisational arrangements and the influence of key actors, including policy champions and boundary spanners.

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Kebede, Almaz Tadesse. "Sustaining the Allideghi Grassland of Ethiopia: Influence of Pastoralism and Vegetation Change." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/309.

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The Allideghi Wildlife Reserve in the Amibara District of Afar Regional State, Ethiopia, has international significance for harboring endangered Grevy's Zebra and other wildlife dependent on grasslands. The reserve is increasingly used by pastoral people and their herds. Impacts of livestock on native vegetation include direct effects of grazing and indirect effects from livestock-facilitated dispersal of an invasive plant, Prosopis juliflora. The main research objective was to determine effects of pastoralism and vegetation change on prospects for sustaining the Allideghi Wildlife Reserve as grassland habitat for Grevy's Zebra. Methods included use of driving surveys to quantify resource use by herbivores, vegetation analysis, and engagement with local people. Resource-use patterns of livestock across the Allideghi grassland were often positively affected by proximity of water, while that for wild ungulates was often negatively affected by proximity of people. Livestock concentration at a major borehole has created a large piosphere with concomitant reductions in herbaceous standing-crop, productivity, and species richness; plant species have shifted from grasses to forbs in severely grazed sites. Vegetation further from the borehole was resilient in response to moderate grazing pressure in terms of species composition and productivity. Since being introduced at a nearby commercial plantation in the 1970s, P. juliflora has been dispersed to the Allideghi Wildlife Reserve via livestock; cattle, sheep, and goats eat the pods and deposit seeds in manure at settlements and favored foraging areas. Prosopis juliflora greatly reduced species richness and basal cover of native herbaceous vegetation in the Allideghi grassland. Analysis of remotely sensed images from the past 30 years indicated major land-use change in the district due to agricultural expansion as well as land-cover change due to Prosopis encroachment and heavy grazing. Recent efforts have been undertaken by various agencies to control P. juliflora, via harvest in the district, but this has yielded variable and often negative results. Without a concerted effort to limit livestock grazing and control spread of P. juliflora, the future for the grassland and wildlife at the Allideghi Wildlife Reserve is grim. Agencies and policy makers need to promote science- and community-based approaches to help rectify the situation. (311 pages)

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Toniolo, Maria Angelica. "The role of land tenure in the occurrence of accidental fires in the Amazon region case studies from the National Forest of Tapajos, Para, Brazil /." [Bloomington, Ind.] : Indiana University, 2004. http://wwwlib.umi.com/dissertations/fullcit/3162264.

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Thesis (Ph.D.)--Indiana University, Dept. of Public and Environmental Affairs and Dept. of Political Science, 2004.
Source: Dissertation Abstracts International, Volume: 66-01, Section: A, page: 0330. Co-Chairs: Elinor Ostrom; Eduardo S. Brondizio. Title from dissertation home page (viewed Oct. 12, 2006).

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Maisonneuve, Mélanie. "La protection des espèces en péril au Canada: Un retard expliqué." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26385.

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La politique canadienne en matière de biodiversité compte des failles importantes, notamment l'adoption tardive d'une loi protégeant les espèces en péril. Au cours des dernières années, le gouvernement fédéral à tenté à trois reprises d'adopter une législation sur les espèces en péril, et le dernier projet, qui a reçu la sanction royale en décembre 2002, a été sévèrement critiqué par plusieurs observateurs. Nous croyons que le gouvernement fédéral a longtemps attendu avant de mettre en place une loi sur les espèces en péril parce qu'il considérait durant de nombreuses années, que dans le contexte du fédéralisme les coûts politiques associés à une telle mesure étaient plus importants que les bénéfices. Plus précisement, nous démontrerons que la théorie mise de l'avant par Kathryn Harrison sur le calcul des coûts et bénéfices sur la mise en place d'une politique (notamment en terme d'appui dans l'opinion publique), est une explication crédible pour comprendre l'élaboration d'une politique environnementale canadienne sur les espèces en péril.

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Trachy, Suzanne 1962. "The Endangered Species Act: Political implications of delisting a recovered species." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/291698.

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The Endangered Species Act of 1973 (ESA) reflects society's concern over the rate of species extinction and aims to halt or reverse this trend. Several policies of the ESA protect listed species over resource development projects. Due to this protection, several listed species have recently experienced a recovery. Two have been removed, or delisted, from the federal Endangered Species list. Once a recovered species becomes delisted, the majority of these protections are removed. This paper analyzes the political implications of such delistings utilizing formal interviews, personal experiences, and a literature search. Through analysis, it is found that two specific policies seem to protect delisted species. It is concluded that a quantitative analysis may be premature at this time due to the small number of recovered species and that these policies must be effected to their fullest potential to ensure the long-term success of the federal endangered species program.

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Remeš, Jiří. "The university forest enterprise in Kostelec nad Černýmil Lesy - a basis for practical education and research at the Faculty of Forestry and Wood Sciences in Prague." Technische Universität Dresden, 2019. https://tud.qucosa.de/id/qucosa%3A34123.

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The paper presents the University Forest Enterprise, established in 1935, as an important part of the Czech University of Life Sciences Prague. The contribution also describes the natural conditions of the enterprise (altitude, climate, geological and soil condition) and the species composition of the forests. Attention is also paid to the organizational structure of the enterprise and to the main activities, being carried out there. These are focused on education and research. However, the number of these activities is stagnating or declining in recent years. Therefore it is necessary to seek a new financing model and start work on the modemization of the facilities and equipment.

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31

Andrews, Garren M. "Post-fire Mortality and Response in a Redwood/ Douglas-fir Forest, Santa Cruz Mountains, California." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/882.

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We investigated how fire severity impacts the survival and response (sprouting/seeding) of multiple species in the Santa Cruz Mountains of coastal California, including coast redwood (Sequoia sempervirens), Douglas-fir (Pseudotsuga menziesii), tanoak (Lithocarpus densiflorus), and Pacific madrone(Arbutus menziesii). During August 2009 the Lockheed Fire burned nearly 3,160ha of mixed-conifer stands with variable severity. Data from 37 Continuous Forest Inventory (CFI) plots were collected immediately before and for 2 successive years following the 2009 Lockheed Fire. This research entails three objectives. First, we quantified post-fire mortality of trees that vary in species, size, and fire severity. Second, data was quantified for post-fire response (sprouting, seeding) of those three tree species in areas of varying fire severity. Third, we developed logistic regression models that predict post-fire mortality and response for each of the three species. Understanding the relationship between burn severity, mortality and regeneration can allow for better post-fire predictive services. This research can support forest managers in post-fire management decisions to facilitate long-term sustainability and protection of environmental infrastructure within coast redwood/Douglas-fir forests.

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Brown, Jasmine. "The Price of a Green Conscience : Social impacts of carbon forestry projects." Thesis, Linnéuniversitetet, Institutionen för samhällsstudier (SS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-101054.

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Scholars and civil society organizations have over the last decade referred to large-scale carbon sequestration TPPs as "carbon colonialism" (Carmody and Taylor, 2016) as well as a "development by dispossession" dressed in new clothing behind words such as climate change mitigation and development (Kröger, 2012). Concerns have been raised that the trade-offs from the implementation of industrial tree plantations (ITPs) may result in conflicting effects on countries' overall development (The Oakland Institute, 2019; Osborne, 2015; Nel & Hill, 2013). Moreover, NGO's and think tanks, such as FIAN (2012) and the Oakland Institute (2017, 2019), have released reports in which such tree planting projects are accused of displacing people and violating human rights (FIAN, 2012; The Oakland Institute, 2017, 2019; Carmody & Taylor, 2016). This thesis explores the impacts of carbon forestry projects, emphasizing the impacts of ITPs on local livelihoods and their subsequent effects on development. Three dimensions have been chosen to limit the scope of this thesis: (1) food security; (2) access to land; and (3) employment & income. The thesis is conducted using a qualitative desk study and secondary analysis of two multiple case studies of Uganda and Mozambique. The findings presented suggest carbon forestry projects may negatively affect all three dimensions, ultimately affecting communities' sustainable development. The author recommends further research to evaluate the complex effects of carbon forestry projects.

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Persha, Lauren. "Decentralized forest management, anthropogenic disturbance patterns and forest change in the Usambara Mountains, Tanzania." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337272.

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Thesis (Ph.D.)--Indiana University, School of Public Environmental and Affairs, 2008.
Title from PDF t.p. (viewed on Jul 28, 2009). Source: Dissertation Abstracts International, Volume: 69-12, Section: B, page: 7386. Adviser: James C. Randolph.

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34

Cashman, Jennifer Lynne 1962. "Desert mule deer response to mitigations along the Hayden-Rhodes Aqueduct, Arizona." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277991.

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The Hayden-Rhodes Aqueduct (HRA) extends from Lake Havasu along the California and Arizona border to 40 km northeast of Phoenix, Arizona. The Bureau of Reclamation established water catchments for wildlife, and wildlife bridges to provide access for wildlife across the HRA. I investigated the effectiveness of these mitigations for desert mule deer (Odocoileus hemionus crooki) from July 1989 to July 1990. I examined deer use of wildlife bridges, concrete overchutes, and water catchments; the quality of deer habitat at crossings; and the influence of mountain lions (Felis concolor) on deer at water catchments. All water catchments were used by deer. There was very little use of wildlife crossings by deer. Deer habitat on the north side of the HRA received more use by deer than habitats south of the HRA. I could not determine if mountain lions capture prey more often near water catchments than in other areas.

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35

Rollins, Matthew Gregory. "Twentieth century fire patterns in the Gila/Aldo Leopold Wilderness areas, New Mexico and the Selway-Bitterroot Wilderness area, Idaho/Montana." Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/284205.

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I used archives of wildfire perimeters (fire atlases) within a geographic information system (GIS) to describe and evaluate fire frequency patterns for the 20th century in the 486,673-ha Gila/Aldo Leopold Wilderness Complex (GALWC), New Mexico and the 785,090-ha Selway-Bitterroot Wilderness Complex (SBWC) in Idaho and Montana. I addressed questions about changing 20th century fire frequencies and landscape-scale controls of fire frequency by analyzing fire atlases along with data for topography, vegetation, and climate. Similarities and differences in comparisons between study areas highlight important aspects of fire regimes and strengthen my interpretation and inference. In the GALWC, fire rotations were shortest during the recent wildfire use period (1975-1993) and longest during the pre-modern suppression period (1909-1946). In the SBWC, fire rotations were shortest during the pre-modern suppression period (1880-1934) and longest during the modern suppression period (1935-1975). Elevations with the highest fire frequencies differed between study areas. However, forest types found at these elevations are characterized by similar overstory tree species. Steeper northeastern slopes in the GALWC and southwestern slopes in the SBWC burned most frequently. I assert that, in the GALWC, horizontal fuel continuity is a main factor determining fire frequency. In the SBWC, fuel moisture status limits fire frequency. Fires are most frequent in areas where ignitions occur and neither fuel continuity nor fuel moisture are likely to limit fire spread. Three statistical modeling approaches were used to produce maps of reburn probabilities. Log-likelihood modeling provided the most satisfactory results, while logistic regression and classification and regression trees yielded statistically insignificant models. Empirical models contributed to the assertion that fuel continuity limits fire frequency in the GALWC while fuel moisture limits fire frequency in the SBWC. Mapped fire perimeters provide a valuable source of spatial historical information for describing the role of large fires over broad areas. This dissertation enhances scientific knowledge about broad scale changes in fire regimes. Comparisons between areas facilitate identification of unique versus general patterns. Results provide a contemporary baseline for comparison with estimates of Pre-EuroAmerican fire frequencies, and a historical, spatial context for modeling and managing future fire regimes.

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Berg, Ivan. "Headwaters and forestry : Effect of riparian buffers on stream physiochemical properties." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-163017.

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Forest management practices usually preserves riparian buffers along watercourses in order to protect stream water from physical, chemical and ecological changes caused by clear-cutting. The purpose of this thesis was to investigate whether there is a relationship between the size of the riparian buffer zone along small streams, i.e., headwaters, and a number of physical and chemical attributes of these streams. Twelve headwaters in the Västerbotten county and twelve in Jönköpings county were investigated. These headwaters had a range of buffer widths from “No buffer” (no trees left), Thin buffer” (< 5 m wide), to “Moderate buffer” (>5 m wide) and “Reference” (no harvest) streams were also included. Tested physical and chemical conditions were light in the riparian zone, air and water temperature, stream bed cover and water chemistry. Buffer width had a significant effect on reducing light levels and temperature in the riparian zone; a buffer width over 13 m on each side of the stream was needed to maintain light and air temperature as in reference conditions. Regarding water temperature, increasing sedimentation and water quality, no significant reducing effect of increasing riparian buffer width was found.

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Rusk, Monica Kirsten 1967. "Selenium risk to Yuma clapper rails and other marsh birds of the lower Colorado River." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/278053.

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I estimated the risk of selenium toxicity to endangered Yuma clapper rail and other marsh birds of the lower Colorado River (LCR). I collected sediment, invertebrates, Virginia rails, and least bitterns from 4 locations within the LCR valley, in May-August 1990, and collected additional bird species from 1 of the sites in April 1991. I analyzed the samples for selenium and other trace elements. Selenium accumulated in the backwater marshes of the LCR and was uniformly distributed among the backwaters sampled. Selenium increased 1-16X between successive trophic levels, however, selenium levels did not differ significantly among species with different diets. Based on the selenium levels in bird tissues and prey species, marsh birds in the LCR valley are at low risk of adult mortality, but moderate to high risk of teratogenicity. The rate of selenium accumulation in the backwaters must be reduced to decrease the risk of toxicity.

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Ruiz, Leslie Diane 1969. "Contaminants in water, sediment, and biota from the Bill Williams River National Wildlife Refuge, Arizona." Thesis, The University of Arizona, 1994. http://hdl.handle.net/10150/278462.

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One hundred sixty two composite samples were analyzed for organochlorine compound residues and 19 trace elements and heavy metals. There was no evidence that flushing of washes in times of flood increases contaminant levels in the Bill Williams River, or that historical mining operations currently contributed to the element load. There was evidence that Colorado River water increased selenium levels in biota in the delta; one hundred percent of fish collected from the confluence of the Bill Williams River and the Colorado River contained elevated selenium concentration (geometric mean = 9.98, range 2.80-17.56 μg/g dry weight). These levels exceed standards set for the protection of predatory species of fish and wildlife.

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Lewis, Glennis M. "Protecting Canada's natural ecosystems from invasive alien plant species: Is sub-national weed control legislation up to the task?" Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27388.

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Invasive alien plant species pose a serious threat to Canada's natural ecosystems. It is the thesis of this paper that sub-national laws are important tools in combatting such species that are naturalized and spreading within provincial and territorial boundaries. Weed control acts in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, Nova Scotia, and Prince Edward Island and the plant health protection acts in New Brunswick, and Newfoundland and Labrador are a strong basis to combat invasive alien plant species. However, since these laws were enacted for weeds in agro-ecosystems, they are not up to the task of protecting natural ecosystems from invasive alien plant species. In some provinces and territories, there is a need to fill gaps in the law and ensure that it applies in a clear and uniform manner to all natural ecosystems. Numerous other revisions are recommended to make applicable provincial and territorial laws more effective.

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Pinheiro, Fabiola M. R. "Effects of forest fires and clear-cutting on mercury loading to boreal lakes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0034/MQ64431.pdf.

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41

Welch, David P. "Multidisciplinary approaches to the study of forest dynamics in south central Indiana and southern Illinois." [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3278462.

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Thesis (Ph.D.)--Indiana University, School of Public and Environmental Affairs, 2007.
Source: Dissertation Abstracts International, Volume: 68-10, Section: B, page: 6564. Adviser: Vicky Meretsky. Title from dissertation home page (viewed May 20, 2008).

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Swallow, Kelly A. "Ancient woodland vegetation : distinctiveness and community ecology." Thesis, University of Gloucestershire, 2018. http://eprints.glos.ac.uk/5800/.

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The high floristic biodiversity value of ancient woodland is widely acknowledged, as is its status as a fragmented habitat of limited spatial extent. The distinctive vegetation of ancient woodland is an important factor in its conservation. Specifically, Ancient Woodland Indicator (AWI) species have been shown to be poor dispersers and incompatible with a fragmented habitat that is subject to environmental change. In recognition of their ecological importance, both Ancient Semi-Natural Woodland (ASNW) and Ancient Replanted Woodland (ARW) are protected by legislation. This thesis took the novel approach of examining the distinctiveness and community ecology of vegetation communities in all three woodland types of ASNW, ARW, and recent woodland. Importantly, analyses were based on new high-granularity primary vegetation and soil data. To address questions raised in the literature regarding the accuracy of ancient woodland and AWI identification, this research examined the metrics used to distinguish these habitats and species. Increasingly, the literature calls for further understanding of the ecological drivers of ancient woodland vegetation distinctiveness. In response, this research tested for differences in species composition of canopy, shrub, herb layer, AWI, and moss communities across all three woodland types. For AWI species, biotic, abiotic, and biogeographical variables were analysed for their contribution to community distinctiveness. Results highlighted the importance of consistency in metric selection when assessing the distinctiveness of ancient woodland and determining indicator species. In addition to the usual alpha scale measure of distinctiveness, assessing richness and community composition at the beta and gamma scales is recommended to inform conservation. Life traits and dispersal mechanisms were important differentiators for herb layer community composition among the woodland types. AWI richness was equally strongly explained by biogeographical variables as by ASNW, ARW, and recent status. Overall, this thesis supported ecological and biogeographical explanations for the distinctiveness of ancient woodland vegetation.

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Hidayat, Noor 1952. "Baseflow evaluation of a logged small watershed of the Bull Run River, Oregon." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/278028.

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The impact of logging operation on baseflow yield on the Bull Run Municipal watershed, Oregon was examined. Daily streamflow data, from 1958 to 1984, for the three small watersheds on the Bull Run river were analyzed. The baseflow recession coefficient was determined by analyses of successive days flows. Least squares and linear regression analysis were utilized to evaluate the effect of treatments. It was shown that logging of 25 percent of total treated watershed reduced mean daily baseflow yield, but this was not significantly different at either the 0.05 or 0.01 level. Also, it was shown by the untreated watershed that there was a significant difference, at the 0.05 level, of baseflow yield between the period of pre- and post-logging. The decreased baseflow yield may have resulted from decreasing fog drip and increasing evaporation rate in the logged areas and from decreasing precipitation on the watersheds during the post-logging period.

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Grunberg, Wolfgang. "Modeling deforestation risk in the Maya Biosphere Reserve, Guatemala." Thesis, The University of Arizona, 2000. http://hdl.handle.net/10150/278736.

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The tropical forest of Guatemala's 21,130 square kilometer Maya Biosphere Reserve and buffer zone is being impacted by deforestation due to an increase of the local population and establishment of over 200 new settlements over the last 20 years. Existing geographic information system databases and remote sensing data were used to determine how much of the observed deforestation could be explained by three factors: roads, human settlements, and soil quality. Each factor was analyzed separately using spatial and statistical analysis methods. These factors were then combined to create a final deforestation risk model. The deterministic model enables policy makers, as well as managers, to create scenarios that assess the impact of their actions on the forest on a regional scale.

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Mosher, Danika. "Past, Current, and Future Potential Distributions of Red Spruce and Fraser Fir Forests in the Southern Appalachians: Interpreting Possible Impacts of Climate Change." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etd/3851.

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Spruce-Fir forests are relicts from the Pleistocene and can only be found within the Southern Appalachians. Analyzing the relationships between species distribution, climatic parameters, topography, and biotic interactions through ecological niche modeling creates prediction maps for conservation efforts. Maxent, Boosted Regression, and Random Forest were utilized to compare which model and variable combinations best approximate the unique mountain forest environment. Maxent with a bias file produced optimal results and was used to examine distributional changes that may occur in the future and how these changes compare to paleo-environmental distributions. Fraser fir has shown evidence of being influenced by changing climates based on historical data and in future predictions. These findings show areas of decline in 2050 and 2070. When combined with weather, climate, genetics, and ecological studies, this is a useful tool for resource allocation to areas that are predicted to be resilient in the face of climate change.

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Belmont, Jonathon. "The study of carbon and nutrients in forests : a foundation for examining global change /." [Bloomington, Ind.] : Indiana University, 2004. http://wwwlib.umi.com/dissertations/fullcit/3162225.

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Thesis (Ph.D.)--Indiana University, School of Public and Environmental Affairs, 2004.
Title from PDF t.p. (viewed Dec. 1, 2008). Source: Dissertation Abstracts International, Volume: 66-01, Section: B, page: 0177. Chair: J. C. Randolph.

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Addessi, Andrew David. "Urban Impacts to Forest Productivity, Soil Quality, and Canopy Structure in Forest Park, Portland, Oregon." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3881.

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Land use practices and exposure to low impact disturbances associated with an urban environment can alter forest structure and function. Past and ongoing research in Forest Park, a large urban forest in Portland, Oregon, suggests that mature mixed Douglas-fir (Psuedotsuga meziesii)-hardwood stands in the more urban end of the park lack a shade-tolerant conifer understory composed of the late successional conifer tree species, such western hemlock (Tsuga heterophylla) and western red-cedar (Thuja plicata). 5-year plot remeasurement data that characterizes productivity and mortality patterns did not show a strong relationship to urban proximity. Plot productivity was generally consistent with values taken from studies of other similarly aged (~100 years old) Douglas-fir /Western Hemlock stands. Mortality was highest in rural plots, and was driven by large windthrow events to canopy trees. Soil organic matter, soil pH, and depth of organic horizon indicated a legacy of soil impact in urban areas most impacted by past intensive logging. The urban mature plot had higher mean soil pH at site (5.87, se: ±0.06) compared to a rural mature, and old growth reference sites located within the park. Although surface organic and A layer soil horizon depth was thinnest at the urban mature site, soil organic matter was not found to be significantly different across sites. Light detection and ranging (LiDAR) data showed that old-growth plots and plots in the middle section of the park had the highest degree of canopy structure as measured by Rumple and standard deviation of point elevation. Measures of stand height showed OG plots and urban plots to have the tallest trees. Rural plots showed a high degree of variability in all LiDAR metrics, showing a wider range of stand height and complexity than urban and middle plots. These results suggest that past land-use and urban proximity affect plot level productivity, soil quality, and above-ground canopy structure in Forest Park. These results clarify how the lack of late-successional tree species might be most linked to differing histories of intensive logging activity within the park. Reduced old-growth legacy features (remnant seed trees, coarse woody debris) in plots with a clear history of aggressive clear-cuts has led to a reduction in regeneration of western hemlock and western red-cedar in the understory.

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48

Loganbill, Andrew Wood. "Post-fire Response of Little Creek Watershed: Evaluation of Change in Sediment Production and Suspended Sediment Transport." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1028.

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The Little Creek watershed was assessed to identify changes in event-based suspended sediment export and determine the factors contributing to sediment production the first year following the Lockheed Fire in 2009. The amount and volume of near-stream sediment sources were found to decrease, while an increase in hillslope sediment production was documented. High intensity, short duration rainfall (up to 87 mm/hr for 10 minute duration) initiated extensive rilling and minor channel-derived debris torrents originating from the upper south facing slopes. Rainfall simulations, hillslope erosion plots, and soil infiltration tests indicated that fire produced soil water repellency, the lack of ground cover, steep slopes, and high soil burn severity were the most influential factors contributing to hillslope erosion. Contrary to results reported in other western U.S. studies, regression analyses determined that the effect of fire significantly decreased suspended sediment concentrations with higher flows at North Fork and Upper North Fork monitoring stations. The effect of the fire did not produce increases in stormflow volumes and event sediment load, likely due to the fact near-stream sediment contribution was minimal and the majority of hillslope-derived sediment sources were not hydrologically connected. This study provides valuable information for landowners and land managers to understand how a coastal redwood dominated watershed responds to wildfire and prepare post-fire mitigation efforts following future wildfires.

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Pacheco, Diego. "An institutional analysis of decentralization and indigenous timber management in common-property forests of Bolivia's lowlands." [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3264317.

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Thesis (Ph.D.)--Indiana University, School of Public Environmental Affairs and Dept. of Political Science, 2007.
Source: Dissertation Abstracts International, Volume: 68-05, Section: A, page: 2152. Adviser: Elinor Ostrom. "Title from dissertation home page (viewed Jan. 12, 2008)."

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Abdulin, Ruslan. "Applying Machine Learning to Detect Historical Remains in Swedish Forestry Using LIDAR Data." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-104885.

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Historical remains in Swedish forests are at risk of being damaged by heavy machineryduring regular soil preparation, scarification, and regeneration activities. Thereason for this is that the exact locations of these remains are often unknown or theirrecords are inaccurate. Some of the most vulnerable historical remains are the tracesleft after years of charcoal production. In this thesis, we design and implement acomputer vision artificial intelligent model capable of identifying these traces usingtwo accessible visualizations of Light Detection and Ranging (LIDAR) data. Themodel we used was the ResNet34 Convolutional Neural Network pre-trained on theImageNet dataset. The model took advantage of the image segmentation approachand required only a small number of annotations distributed on original images fortraining. During the process of data preparation, the original images were heavilyaugmented, which bolstered the training dataset. Results showed that the model candetect charcoal burners sites and mark them on both types of LIDAR visualizations.Being implemented on modern frameworks and featured with state-of-art machinelearning techniques, the model may reduce the costs of surveys of this type of historicalremains and thereby help save cultural heritage.

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Dissertations / Theses on the topic 'Forestry Sciences'

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