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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.
1

Spatial distribution of understory vegetation in tree canopy gaps of the Pacific Northwest /

London, Sharon Gail. January 1999 (has links)
Thesis (M.S.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 101-104). Also available via the World Wide Web.
2

Effects of timber harvest and forest edges on abundance, viability, and physiology of understory plants in Pseudotsuga forests of western Washington /

Nelson, Cara Ritchie. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 83-96).
3

Effects of canopy gaps in Douglas-fir forests and resource gradients on fecundity and growth of understory herbs /

St. Pierre, Elizabeth A. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 135-144). Also available on the World Wide Web.
4

The fate of Chinese understory species in coniferous forests of the Pacific Northwest : the role of light

Brooke, Molly Muir, January 2006 (has links) (PDF)
Thesis (M.S. in botany)--Washington State University, December 2006. / Includes bibliographical references (p. 92-100).
5

Nutrient and tannin concentrations of shrub leaves in managed and unmanaged forests of the Oregon Coast Range : implications for herbivores /

Lange, Karen M. January 1998 (has links)
Thesis (M.S.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 40-47). Also available on the World Wide Web.
6

Biological diversity associated with bigtooth aspen patches in a mixed oak forest

Larrimer, Audrey K. 25 June 2004 (has links)
No description available.
7

Response of the understory to low intensity prescribed burning or mechanical and herbicide treatment in a northern mesic eastern white pine (Pinus strobus L.) forest in the Menominee Nation, Wisconsin /

Webster, Bobbie J. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2008. / Submitted in partial fulfillment of the degree Master of Science in Natural Resources (Forest Ecology), College of Natural Resources. Includes bibliographical references (leaves 122-128).
8

Introdução de espécies de sub-bosque em áreas de restauração de florestas estacionais semideciduais / Introduction of Understory species in Brazilian Seasonal Semidecidual Forests restoration areas

Pardi, Mariana Meireles 07 February 2014 (has links)
Espécies típicas de sub-bosque são pouco estudadas quanto à sua aplicação na restauração e enriquecimento de florestas degradadas. São em geral arvoretas ou arbustos finais de sucessão, tolerantes ao sombreamento, capazes de germinar, se estabelecer e completar seu ciclo de vida neste ambiente, representando importante fonte de recursos como alimento e abrigo para polinizadores e dispersores. Porém, não são amplamente utilizadas nos plantios de restauração por não serem espécies de dossel, e em paisagens altamente fragmentadas há poucas chances de chegarem naturalmente em áreas em processo de restauração. Visando contribuir para o desenvolvimento de técnicas de plantio e enriquecimento em áreas degradadas ou em processo de restauração que favoreçam a recuperação do subbosque, este trabalho teve o objetivo de avaliar a sobrevivência e o crescimento de mudas de 10 espécies típicas de sub-bosque plantadas em quatro diferentes condições: plantio inicial de restauração, áreas em processo de restauração com 5 e 10 anos de idade e um fragmento remanescente degradado. Todas as áreas de estudo localizam-se na região de Batatais, SP e estão inseridas no Bioma Mata Atlântica, mais especificamente na fisionomia de Floresta Estacional Semidecidual. As mudas foram plantadas em janeiro de 2012 e observadas durante 15 meses quanto ao crescimento e sobrevivência. As áreas de estudo foram caracterizadas quanto aos atributos químicos, físicos e granulométricos do solo, cobertura e florística do dossel. A análise de componentes principais (PCA) mostrou que entre estas variáveis a que teve maior relação com o crescimento relativo das mudas foi a cobertura do dossel. A área que teve maior eficiência na introdução das espécies típicas de sub-bosque, considerando crescimento e sobrevivência, foi o plantio inicial de restauração, onde 3 espécies foram muito eficientes e 6 foram eficientes. No plantio com 5 anos 1 espécie foi muito eficiente e 4 foram eficientes, porém, cresceram bem menos que no plantio inicial. Os resultados apontaram ainda que apenas 3 espécies foram eficientes na área em processo de restauração de 10 anos e nenhuma no fragmento remanescente degradado, mostrando a dificuldade de se realizar o enriquecimento de áreas com alto nível de sombreamento, e de se reverter o processo de degradação nessas áreas, reforçando a importância da utilização de alta diversidade de espécies e grupos funcionais nos plantios de restauração e da conservação das áreas florestais remanescentes. / Species typical from understory layers are poorly studied regarding their use in restoration and enrichment of degraded forests. They are generally treelets or shrubs of final successional phase, shade tolerant, able to germinate, establish and complete their life cycle in this environment. They are an important source of resources as food and shelter to pollinators and dispersers. Despite their ecological importance, these plants have not been widely used in restoration plantings because they are not canopy species. In fragmented landscapes, these species have little chance of being recruited naturally into areas undergoing restoration. In order to contribute to the development of techniques of planting and enrichment in degraded areas or areas being restored and promote the recuperation of understory layers, this study evaluated the survival and growth of seedlings of 10 understory species planted under four different conditions: initial planting; 5-year-old restoration area; 10- year-old restoration area; and degraded forest fragment. All sites are located in the region of Batatais, SP, Brazil, inside the Atlantic Forest biome, specifically in the Seasonal Semidecidual Forest type. Seedlings were planted in January 2012 and measured during 15 months for their survival and growth. Study sites were characterized regarding soil chemical and physical attributes and granulometry, and canopy composition and coverage. Principal components analysis (PCA) showed that relative growth of seedlings was more strongly related to canopy coverage. Considering survivorship and growth, introduction of understory species was more successful at the initial planting site, where three species were very successful and six were successful. In the 5-year-old restoration area, one species was very successful and four were considered successful, however, they grew considerably less than at the initial planting site. Results point out that only three species were successful at the 10-year-old restoration area and none at the forest fragment, which shows the difficulty of enriching areas with high levels of shading, and thus, the difficulty of reversing degradation of forest remnants. This reinforces the importance of using high diversity of species and functional groups in restoration plantings and also of conserving remnant forests.
9

Does small-scale land use affect the understory birds negative in the Peruvian National Reserve Allpahuayo Mishana? / Påverkar småskalig markanvändning undervegetations fåglarna negativt i det peruanska reservatet Allpahuayo Mishana?

Svensson, Ofir January 2014 (has links)
Human activities that lead to fragmentation and habitat loss are big problems in the world. Due to global climate change the negative effects of fragmented habitats can be catastrophic for many organisms. In the Amazon rainforest, that is most sensitive to human impact, stands a big risk to lose its species diversity. Fragmentation and climate change together seems to escalate the death rate of rainforest plants and that will change the whole ecosystem. Birds and insects are depending on the trees and the trees faces big challenges now. Many of the rainforest organisms have been noticed to emigrate further up to northern altitudes due to the warmer climate and maybe also because of deforestation. Many of the lowland forest birds are predicted to distribute from their origin habitats. The national reserve Allpahuayo Mishana in the Peruvian Amazon is known for its diversity of birds. It is a big challenge for the reserve to maintain the origin forest composition from climate change, which will lead to losses of species. The reserve allows the local community to utilize the land for small-scale uses inside the protected zone. Many of the birds are sensitive for external disturbance. Most human activities are resulting in that the forest becomes less dense, which can lead to that the territory for the birds decreases. This makes it important for the reserve to improve the human land use not to restrict the birds' habitat inside the reserve. This project will investigate if the small-scale land uses affects the understory birds’ diversity and habitat negative. The purpose is to see if the fragmented forests in the reserve, closest to the utilized land, can functioning as a secondary forest for the understory birds, or are the understory birds limited by the small-scale land use, in the national reserve Allpahuayo Mishana? Four sites with various human activities were chosen to investigate if the sites contain any understory birds. The result showed that the most disturbed sites had poor bird diversity compare to the sites with no human disturbance.
10

Seral stage, site conditions, and the vulnerability of understory plant communities to forest harvesting /

Smith, Jason Richard. January 2005 (has links)
Research Project (M.R.M.) - Simon Fraser University, 2005. / Theses (School of Resource and Environmental Management) / Simon Fraser University. Research Project (School of Resource and Environmental Management) / Simon Fraser University.

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