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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.
81

Oak Savanna Restoration and Management in the Mid-South

Barrioz, Seth A 01 May 2010 (has links)
Oak savannas are among the most imperiled ecosystems in the United States as a result of habitat degradation and consequently, associated vegetation and wildlife communities have also declined. I evaluated savanna restoration strategies on twelve case studies in Tennessee and Kentucky. These case studies represented a broad range of disturbances and the most advanced savanna restoration sites within the region. I evaluated vegetation and breeding bird responses to landscape and overstory conditions across sites through a meta-analysis. Total grass and forb cover were influenced by overstory metrics but not by topography (P >0.05). Oak regeneration density was influenced by canopy cover, while oak competitor regeneration density was influenced by percent slope and sapling density (P <0.05). With respect to breeding birds, I found forest species persisted within case studies despite substantial disturbance; shrub/scrub birds were common on disturbed sites. Only three obligate grassland bird species, Tyrannus tyrannus, Aimophila aestivalis, Spiza americana, were observed on my sites. Relative abundance of Passerina cyanea was positively related to the groundlayer development; whereas that of Melanerpes erythrocephalus was positively related to basal area of dead trees (P <0.05). Based on my results, canopy reduction and growing-season burns may both be critical for the restoration of savannas within the region. Drum-chopping is a tool that may expedite oak savanna restoration through improved woody competition control, however, its effectiveness has not been investigated. Therefore, I evaluated drum-chopping effects on vegetative structure at Catoosa Wildlife Management Area, Tennessee, during 2008 and 2009 using two adjacent sites with similar fire and overstory removal histories. One site was subjected to drum-chopping in September of 2007, while an adjacent site (control) was not chopped. Drum-chopping reduced grass and forb cover, and oak seedling density, but increased bare ground and density of vines and shrubs versus the control (P <0.05). Except for bare ground, differences were no longer apparent in the second year. Based on my results, drum chopping may reduce midstory vegetation too thick to be effectively controlled by fire, but otherwise has limited utility as a restoration tool. Although wildlife managers have tried to restore savannas using prescribed fire and overstory canopy removal, use of other tools may be warranted. One such method is drum-chopping, which has been used elsewhere to reduce woody competition. However, the effectiveness of this method in restoring oak savannas has not been evaluated. Therefore, I evaluated drum-chopping effects on plant composition at Catoosa Wildlife Management Area on the Cumberland Plateau in Tennessee. Two adjacent sites with similar fire and overstory removal histories were selected for this study. One of these sites was subjected to drum-chopping (CHOP) in September of 2007, the adjacent site was not chopped (NOCHOP). Grass cover differed by treatment (P <0.01) and year*treatment (P = 0.03). Forb cover differed by treatment (P <0.01) and legume cover differed by year (P <0.01), treatment (P <0.01), and year*treatment (P = 0.01). Exposed bare ground differed by year (P <0.01) and treatment (P <0.01). Exposed leaf litter differed by year (P <0.01). Vines and shrubs (<1.37m tall) differed by treatment (P <0.01). Oak seedling (0-30.48 cm tall) densities differed by treatment (P = 0.05). Based on my results, drum chopping may be a valuable tool where woody encroachment has become too thick for fire to be effective or herbicides are not a viable option, but otherwise has limited utility as a tool for oak savanna restoration.
82

Oak Savanna Restoration and Management in the Mid-South

Barrioz, Seth A 01 May 2010 (has links)
Oak savannas are among the most imperiled ecosystems in the United States as a result of habitat degradation and consequently, associated vegetation and wildlife communities have also declined. I evaluated savanna restoration strategies on twelve case studies in Tennessee and Kentucky. These case studies represented a broad range of disturbances and the most advanced savanna restoration sites within the region. I evaluated vegetation and breeding bird responses to landscape and overstory conditions across sites through a meta-analysis. Total grass and forb cover were influenced by overstory metrics but not by topography (P >0.05). Oak regeneration density was influenced by canopy cover, while oak competitor regeneration density was influenced by percent slope and sapling density (P <0.05). With respect to breeding birds, I found forest species persisted within case studies despite substantial disturbance; shrub/scrub birds were common on disturbed sites. Only three obligate grassland bird species, Tyrannus tyrannus, Aimophila aestivalis, Spiza americana, were observed on my sites. Relative abundance of Passerina cyanea was positively related to the groundlayer development; whereas that of Melanerpes erythrocephalus was positively related to basal area of dead trees (P <0.05). Based on my results, canopy reduction and growing-season burns may both be critical for the restoration of savannas within the region. Drum-chopping is a tool that may expedite oak savanna restoration through improved woody competition control, however, its effectiveness has not been investigated. Therefore, I evaluated drum-chopping effects on vegetative structure at Catoosa Wildlife Management Area, Tennessee, during 2008 and 2009 using two adjacent sites with similar fire and overstory removal histories. One site was subjected to drum-chopping in September of 2007, while an adjacent site (control) was not chopped. Drum-chopping reduced grass and forb cover, and oak seedling density, but increased bare ground and density of vines and shrubs versus the control (P <0.05). Except for bare ground, differences were no longer apparent in the second year. Based on my results, drum chopping may reduce midstory vegetation too thick to be effectively controlled by fire, but otherwise has limited utility as a restoration tool. Although wildlife managers have tried to restore savannas using prescribed fire and overstory canopy removal, use of other tools may be warranted. One such method is drum-chopping, which has been used elsewhere to reduce woody competition. However, the effectiveness of this method in restoring oak savannas has not been evaluated. Therefore, I evaluated drum-chopping effects on plant composition at Catoosa Wildlife Management Area on the Cumberland Plateau in Tennessee. Two adjacent sites with similar fire and overstory removal histories were selected for this study. One of these sites was subjected to drum-chopping (CHOP) in September of 2007, the adjacent site was not chopped (NOCHOP). Grass cover differed by treatment (P <0.01) and year*treatment (P = 0.03). Forb cover differed by treatment (P <0.01) and legume cover differed by year (P <0.01), treatment (P <0.01), and year*treatment (P = 0.01). Exposed bare ground differed by year (P <0.01) and treatment (P <0.01). Exposed leaf litter differed by year (P <0.01). Vines and shrubs (<1.37m tall) differed by treatment (P <0.01). Oak seedling (0-30.48 cm tall) densities differed by treatment (P = 0.05). Based on my results, drum chopping may be a valuable tool where woody encroachment has become too thick for fire to be effective or herbicides are not a viable option, but otherwise has limited utility as a tool for oak savanna restoration.
83

The public land manager in collaborative conservation planing: a comparative analysis of three case studies in Montana

Byrd, Lawrence Allen January 2009 (has links)
Thesis (MA)--University of Montana, 2009. / Contents viewed on November 29, 2009. Title from author supplied metadata. Includes bibliographical references.
84

Internet access, practice adoption, and conservation program participation in three Alabama watersheds

Tallant, Meredith L., Molnar, Joseph J. January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
85

Organising for sustainable natural resource management : representation, leadership and partnerships at four spatial scales /

Rockloff, Susan Fay. January 2003 (has links)
Thesis (Ph.D.)--Murdoch University, 2003. / Thesis submitted to the Division of Science and Engineering. Bibliography: p. 433-481.
86

The contribution of multi-tenure reserve networks to biodiversity conservation

Fitzsimons, James Andrew. Fitzsimons, James Andrew. January 2004 (has links)
Thesis (Ph. D.)--Deakin University, 2004. / Title from PDF title page (viewed on Aug. 23, 2005). Appendix 19 (p. 297-313): Attitudes and perceptions of land managers and owners in the Grassy Box Woodlands Conservation Management Network : a draft confidential report for the New South Wales National Parks & Wildlife Service. 2002. Includes bibliographical references.
87

Water power and forestry in Wisconsin issues of conservation, 1890-1915 /

East, Dennis. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
88

Trees in the Agricultural Matrix: Reforestation Processes in a Tropical Dry Landscape in Chinandega, Nicaragua

Duffy, Brittany A 06 July 2016 (has links)
Tree management practices in the tropical dry forest region of Nicaragua were examined to determine opportunities and factors influencing tree-planting initiatives and forest recovery within the agricultural matrix. A 217.11 ha tree inventory and 44 social surveys were conducted in three rural communities. The inventory found 88 species, 66.68% were native, and 70 valued for multiple uses. Farmers’ reasons for maintaining trees varied, emphasizing live fencing, wood, and fruit. The landscape also contains a tree plantation and a riparian forest, and the origins and management of these tree cover components of the landscape are also considered. Tree planting interventions should supplement extant stakeholder motivation with technical training and basic materials only as explicitly requested by participants, rather than imposing costly or inappropriate project preferences. Initiatives should also focus on smallholders and on multi-use native species suggested by stakeholders in order to maximize the economic, social and environmental benefits provided.
89

Ecology and Conservation of Endangered Species in Sumatra: Smaller Cats and the Sumatran Rhinoceros (Dicerorhinus Sumatrensis) As Case Studies

Pusparini, Wulan 29 August 2014 (has links)
While we should celebrate the bicentennial of naming the Sumatran rhinoceros (SR), the only extant population on earth might be on the island of Sumatra. Since Strien's 1986 study in Mamas Valley, Leuser, very little more has been learned about how this species distributed and what factors are influencing its extirpation. This study is the first conducted in Sumatra at an Island-wide scale. Using hierarchical models, I estimate the occurrence rates (%) and indices of abundance of SR on three remaining population areas: Leuser Landscape (LL) in 2007 (2.77%, 26 (CI 12-61)), Way Kambas (WK) in 2008 (33.58%, 27 (CI 14-50)) and Bukit Barisan Selatan (BBS) in 2010 (36.4%, 31 (CI 19-66)). Primary dry land forest and rivers are factors affecting SR occurrence in LL, but the index of abundance also is affected by deforestation, roughness of terrain, and and a vegetation index. The index of abundance in WK is more affected by major roads, and brush and savannah cover types, and the occurrence there is additionally affected by deforestation. Secondary dry land forest, regular roads, and deforestation is affecting both the occurrence rate and index of abundance of SR in BBS. The identification of these environmental and disturbance factors is translated into spatially explicit map that can be used to update the IUCN distribution map. In LL, by comparison to the historical distribution based on Strien (1986), the small population in Bendahara Mountain might still persist outside the core population in Mamas Valley.
90

Assessing the Impacts to Society Associated with the Use of Alternative Ammunition for Hunting on National Wildlife Refuges

Cahill, Christopher 02 April 2021 (has links)
Attempts to eliminate lead ammunition use for hunting through regulatory approaches can be controversial and contentious, despite extensive scientific evidence of the detrimental effect of lead on wildlife species. In the United States, voluntary approaches to non-lead use that have used outreach and education in place of regulatory approaches have achieved sustained behavioral change in hunter ammunition choice. However, voluntary approaches to alternative ammunition use can be confronted with both practical and social barriers. In collaboration with U.S. Fish and Wildlife Service and U.S. Geological Survey Cooperative Research Units Program, this study assessed the practical and social barriers associated with a voluntary approach to transitioning to non-lead ammunition for hunting white-tailed deer (Odocoileus virginianus) on targeted National Wildlife Refuges in the Northeast United States. This thesis is presented in two sections. Section one examines the continued use of lead ammunition in the context of the North American Model of Wildlife Conservation (the Model). The Model presents a unique approach to wildlife conservation grounded in the sustainable use of wildlife resources maintained in a public trust. In accordance with the Model, wildlife resources in the trust are managed by the government at a population level to maintain trust resources in perpetuity for the benefit of current and future generations of the American public. Continued lead ammunition use for hunting that facilitates pathways to exposure for non-target species presents a unique challenge to a core principle of the Model – known as legitimate purpose -- and questions whether lead ammunition use can align with the Model even in the absence of population level impacts. In addition, chapter one explores whether continued lead ammunition use can be considered ethical hunting behavior under the current definition of a “clean kill”. Chapter two presents the results of a both a quantitative mail-back survey and qualitative focus group discussions conducted at three refuges in the Northeast Region: Rachel Carson in Maine, Edwin B. Forsythe in New Jersey and Rappahannock River Valley in Virginia. The mail-back survey assessed how current lead users view the practical barriers associated with the voluntary use of non-lead ammunition for the purpose of harvesting white-tailed deer and what factors would influence hunters to switch. Focus group discussions assessed hunter understanding of the mechanism of exposure for non-target species and how hunters contextualize the continued use of lead ammunition for the purpose of harvesting white-tailed deer.

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