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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The simulation modeling of supply logistics of forest biomass in British Columbia

Mahmoudi, Mohammadhossein 11 1900 (has links)
The search for alternative energy sources has increased interests in forest biomass. During the last few years, the sever infestation of the Mountain Pine Beetle (MPB) within the Interior BC forests has led to huge volumes of dead wood that exceed the capacity of the lumber industry. One way to make the most value of the surplus wood is to use it as the feedstock for bioenergy. The forest biomass can be supplied through conventional (roadside residuals), full-tree chipping, or satellite yard systems. This thesis presents the development of a simulation model of supply logistics of forest biomass and its application to a case of supplying MPB-killed biomass from Quesnel Timber Supply Area (one of the most infested areas in the Interior BC) to a potential 300 MW power plant adjacent to the city of Quesnel. The model has the ability of providing estimates of quantity, delivery cost, and moisture content of biomass which are critical in feasibility study of any bioenergy project. The results obtained from simulation model showed a delivery cost of C$45 per oven dry tonne of wood chips to the power plant. The results also revealed that the feedstock recovered from roadside residues in one year meets about 30% of the annual demand of the power plant. Potential increase in the Allowable Annual Cut (AAC) for Quesnel TSA increases the quantity of biomass supplied from roadside residuals. However, as long as the biomass is supplied only through conventional harvesting, increasing the AAC even by 40% does not provide enough feedstock to meet the annual demand of the plant. Using the simulation modeling, this research has the benefit of considering the logistics of forest biomass supply as an integrated and interacting system as well as providing different critical parameters over time. The model also has the potential of considering dynamic and random behavior of the logistics system of supplying forest biomass. The model can be modified and applied to similar cases of conventional forest biomass supply. It also can be extended to other harvesting systems including satellite yard and whole-tree chipping.
12

An airborne Lidar canopy segmentation approach for estimating above-ground biomass in coastal eucalypt forests

Turner, Russell Sean, School of Biological, Earth & Environmental Science, UNSW January 2006 (has links)
There is growing interest in airborne lidar for forest carbon accounting and precision forestry purposes. Airborne lidar systems offer a cost-effective, versatile, operationally flexible and robust sampling tool for forest managers. The objective of this study was to develop and test lidar canopy surface enhancement and segmentation processes for estimating dominant above-ground biomass (DAB) in a harvested eucalypt forest on the Central Coast of New South Wales (Australia). The Crown Infill, Trim and Smooth (CITS) process, incorporating a series of filters, algorithms, and selective multi-stage smoothing, was used to enhance lidar canopy surfaces prior to segmentation. Canopy segmentation was achieved using a vertical crown template approach termed the Spatially and Morphologically Isolated Crest (SMIC) process. SMIC delineates dominant tree crowns by detecting elevated crown crests within a 3D lidar canopy surface. Consolidated crown units constitute the basic sampling, analysis and reporting units for wall-to-wall forest inventory. The performance, sensitivity and limitations of these procedures were evaluated using a combination of simulated forest models and actual lidar forest data. Automated crown polygons were used as a sampling template to extract dominant tree height values which were converted to DAB estimates via height-to-biomass relationships derived from field survey and on-site destructive sampling. Results were compared with field based tree height and biomass estimates. Compared against a manually derived crown map from a 2ha field plot, canopy segmentation results revealed a producer???s accuracy of 76% and overall accuracy of 67%. Results indicated a trend toward greater crown splitting (fragmentation) as trees increase in age, height, stem diameter and crown size. Extracted dominant tree height values were highly correlated with ground survey height estimates (r2 0.95 for precision survey and r2 0.69 for standard survey). There was also no significant difference between SMIC and manual crown height estimates. SMIC units overestimated ground-based DAB by 5%; this increased to 36% with the inclusion of segmentation errors. However, SMIC estimation of total plot above-ground biomass (AGB) was within 9% of the ground-based estimate. Results are encouraging considering the mixed-species, multi-aged composition of the forest, and the combined effects of SMIC segmentation and lidar height errors.
13

Carbon accumulation at the Harvard Forest : a comparison of methods for measuring tree biomass for regional extrapolation of the eddy-flux tower footprint /

McKain, Kathryn. January 2005 (has links) (PDF)
Undergraduate honors paper--Mount Holyoke College, 2005. Dept. of Biological Sciences. / Includes bibliographical references (leaves 70-76).
14

Development of economic analysis models for woody biomass to biofuels in central Appalachia

Wu, Jinzhuo. January 2010 (has links)
Thesis (Ph. D.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains vii, 199 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.
15

The simulation modeling of supply logistics of forest biomass in British Columbia

Mahmoudi, Mohammadhossein 11 1900 (has links)
The search for alternative energy sources has increased interests in forest biomass. During the last few years, the sever infestation of the Mountain Pine Beetle (MPB) within the Interior BC forests has led to huge volumes of dead wood that exceed the capacity of the lumber industry. One way to make the most value of the surplus wood is to use it as the feedstock for bioenergy. The forest biomass can be supplied through conventional (roadside residuals), full-tree chipping, or satellite yard systems. This thesis presents the development of a simulation model of supply logistics of forest biomass and its application to a case of supplying MPB-killed biomass from Quesnel Timber Supply Area (one of the most infested areas in the Interior BC) to a potential 300 MW power plant adjacent to the city of Quesnel. The model has the ability of providing estimates of quantity, delivery cost, and moisture content of biomass which are critical in feasibility study of any bioenergy project. The results obtained from simulation model showed a delivery cost of C$45 per oven dry tonne of wood chips to the power plant. The results also revealed that the feedstock recovered from roadside residues in one year meets about 30% of the annual demand of the power plant. Potential increase in the Allowable Annual Cut (AAC) for Quesnel TSA increases the quantity of biomass supplied from roadside residuals. However, as long as the biomass is supplied only through conventional harvesting, increasing the AAC even by 40% does not provide enough feedstock to meet the annual demand of the plant. Using the simulation modeling, this research has the benefit of considering the logistics of forest biomass supply as an integrated and interacting system as well as providing different critical parameters over time. The model also has the potential of considering dynamic and random behavior of the logistics system of supplying forest biomass. The model can be modified and applied to similar cases of conventional forest biomass supply. It also can be extended to other harvesting systems including satellite yard and whole-tree chipping. / Forestry, Faculty of / Graduate
16

Forest Degradation and Governance in Central India: Evidence from Ecology, Remote Sensing and Political Ecology

Agarwala, Meghna January 2015 (has links)
There is no clear consensus on the impact of local communities on the resources they manage, primarily due to a shortage of studies with large sample sizes that incorporate multiple causal factors. As governments decentralize resource management to local communities, it is important to identify factors that prevent resource degradation, to inform more effective decentralization, and help the development of institutional characteristics that prevent resource degradation. This study used remote sensing techniques to quantify forest biomass in tropical deciduous forests in Kanha Pench landscape of Central India, and used these metrics to identify factors associated with changes in forest biomass. Kanha Pench landscape was chosen because of its variation in forest use, and because forests were transferred over a period where satellite imagery was available to track changes. To verify that remote- sensing measured changes indeed constitute degradation, I conducted ecological studies in six villages, to understand changes in biomass, understory, canopy, species diversity and long-term forest composition in intensively used forests. To understand the impact of institutional variables on changes in forest, I interviewed members of forest management committees in fifty villages in the landscape, and tested which institutional variables were associated with changes in forest canopy since 2002, when the forests were decentralized to local communities. The empirical results are of particular conservation significance in India, where further decentralization of forests to local communities in scheduled under the Forest (Dwellers) Rights Act, 2006. Results indicate that local forest use is associated with decreases in forest biomass, understory, canopy cover, and changes in vegetation structure, species richness and diversity. Most importantly, I found that human use has the potential to alter long- term forest composition as transition of some species to higher size classes is altered where humans use forest more intensively. Particularly, species that are fire and trampling resistant are more likely to become mature trees in intensely used forests. Thus, local forest use is associated with forest degradation as the long-term trajectory of the forest is altered, and forests may not be able to provide ecosystem services including livelihood needs such as fuelwood, construction, and non-timber forest products in the future. At a broader scale, remote sensing techniques (optical imagery Landsat and RADAR imagery ALOS-PALSAR FBD) were able to quantify forest biomass at an acceptable accuracy (67 percent), while more easily operatable MODIS based EVI was not. Landscape analysis showed that changes in forest biomass from 2007 to 2010 were associated with high population density, high fire radiative power and greater distance to towns. Since people only travel approximately 2 kilometers for subsistence forest use, the significance of greater changes further from towns suggests that, at a broader landscape scale, forest degradation is not primarily due to local use, but may be a result of other factors. Action taken to exclude outsiders and lower meeting frequency of committees (never) were identified as institutional variables associated with remotely-sensed positive change in canopy over the period when forest management was transferred (2002 to 2010). Villages with no meetings were also associated with higher incumbency of committee Chairpersons and lower incumbency of other committee members. Simultaneously, while economic payments increased awareness and participation in forest management committees, economic payments were not associated with any action to exclude outsiders from forest use. This suggests that managers need to focus on factors besides economic payments to incentivize committees to exclude outsiders, especially as it is associated with positive changes in the forest. Further, while elite capture of resources (as indicated by incumbency and lack of inclusiveness in decision-making) is not helpful for social equity, it does not appear to be detrimental for forests. Overall, this study suggests a number of management strategies to reduce forest degradation. Managers could focus on forests at a distance from towns and roads, as this is where most negative change in forests appears to occur. They could also work with local communities so that their use of forests does not prevent regeneration of species important for ecosystem services. Managers could also work with committees to find strategies other than economic payments for incentivizing community protection of forests.
17

Aboveground biomass and ecosystem carbon pools in tropical secondary forests growing in six life zones of Costa Rica /

Cifuentes-Jara, Miguel. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
18

Relationship between allometric variables and biomass in western juniper (Juniperus occidentalis) /

Sabin, Breanna S. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 42-44). Also available on the World Wide Web.
19

Forest biomass estimation with hemispherical photography for multiple forest types and various atmospheric conditions /

Clark, Joshua Andrew. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 160-172). Also available on the World Wide Web.
20

The willingness of non-industrial private forest landowners to supply wood biomass for a prospective wood-based bioenergy industry a case study from Lee County, Alabama /

Paula, Ana Luiza de Campos, Bailey, Conner, Morse, Wayde C., January 2009 (has links)
Thesis--Auburn University, 2009. / Abstract. Vita. Includes bibliographical references (p. 60-67).

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