Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 173 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references.

Includes bibliographical references (leaves 43-45). / Cover title. "Center for Wildlife Ecology." Also available in print.

Thesis (M.Sc.), Memorial University of Newfoundland, 1999. / Bibliography: p. 208-219.

Thesis (M.S.)--Southern Oregon University, 2008. / Includes bibliographical references (p.135-142 ). Also available via Internet as PDF file through Southern Oregon Digital Archives: http://soda.sou.edu. Search Bioregion Collection.

Thesis (Ph. D.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains xiii, 181 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.

Thesis (M.S.)--East Tennessee State University, 2002. / Abstract. Includes bibliographical references (leaves 35-36). Also available via Internet. Adobe Acrobat .pdf file, requires Adobe Acrobat Reader software.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 88-92). Also available on the World Wide Web.

Thesis (M.S.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Clayton B. Marlow. Includes bibliographical references (leaves 48-52).

O fogo é um fator ecológico essencial no Cerrado e promotor de sua evolução. Não apenas a incidência do fogo afeta as respostas dos ecossistemas, mas principalmente o regime de queima, composto por componentes temporais, espaciais e de magnitude. O manejo por meio de queimadas controladas é legalmente permitido no Brasil, mas ainda é encarado com restrições. Como consequência, há uma lacuna no conhecimento das respostas da vegetação ao fogo. Este projeto avaliou o efeito da época do fogo na comunidade nativa de um campo sujo com presença de espécies invasoras na Estação Ecológica de Itirapina, SP. Estabelecemos 16 parcelas (15 x 15 m) e determinamos 3 tratamentos de queima - precoce, modal e tardia - e controle, cada qual com 4 réplicas. Em cada parcela, foram instaladas 10 sub-parcelas fixas (1 x 1 m), nas quais foram obtidos dados de estimativa de cobertura de graminóides, arbustos, herbáceas não graminóides, palmeiras, solo nu e necromassa. Os resultados mostram que diferentes épocas de queima geraram diferentes efeitos em gramíneas e solo nu, mas essas diferenças não se mantiveram um ano após as queimas. Constatamos a diminuição dos valores iniciais de cobertura de necromassa e o aumento na cobertura de arbustos para todos os tratamentos de queima. Não obtivemos resultados conclusivos para herbáceas não graminóides e vimos que a cobertura de palmeiras não foi afetada pelo fogo. Os resultados evidenciam a resiliência do Cerrado, já que o estrato herbáceo-arbustivo se regenerou dentro de 1 ano. A recuperação da vegetação pôde ser explicada pela sazonalidade climática, sendo que uma estação chuvosa foi suficiente para que as diferenças entre as épocas de queima desaparecessem. O manejo de fogo para redução de material combustível foi comprovado e vimos que pode ser realizado em qualquer época do ano. Obtivemos indícios de que a queima pode aumentar a susceptibilidade de invasão por Urochloa brizantha e indicamos que o manejo de fogo em ambientes invadidos por U. brizantha seja realizado com cautela, até que tenhamos certeza de que o fogo não facilita a proliferação dessa espécie invasora / Fire is an essential ecological factor that has promoted the evolution of Cerrado vegetation. Not only the incidence of fire affects the ecosystem, but mainly the fire regime, which is characterized by variability in space, time, and magnitude. Time, specifically, is related to fire frequency and seasonality. The use of fire as a management tool is legally admitted in the Brazilian protected areas, but it is still seen with great restrictions. As a consequence there is a knowledge gap on the vegetation responses to fire. This project evaluated short time effects of fire season on the herbaceous community of a “campo sujo” (open savanna), in the Itirapina Ecological Station, a protected area in the State of São Paulo, Brazil. We established 16 plots (15 x 15 m) and three fire treatments - burning in the early, middle or late dry season - and control (not burning), each treatment with four replicates. In each plot we established ten fixed subplots (1 x 1 m), where we estimated the vegetation cover of grasses, shrubs, forbs, palms, as well as bare soil and dead biomass, before burning and every four months during 12 months. We found that grasses and bare soil cover responded differently to the fire season, but differences among treatments disappeared after one year. Litter cover decreased and shrubs cover increased in every fire treatment after one year. Palms were not affected by any fire treatment, and we did not obtain conclusive results for forbs. Our results show that Cerrado vegetation is very resilient, since the components of the herbaceous community recovered within a year. The vegetation recovery was influenced by climate seasonality, and differences among fire seasons disappeared after just one rainy season. When considered as a management tool, fire was efficient in decreasing the amount of dead biomass after one year, and for this purpose it can be applied at any time of the year. Evidence suggested that fire might increase the invasion by Urochloa brizantha, an African grass. For this reason we suggest caution when using fire as a management tool in invaded ecosystems until one is sure that fire will not trigger or facilitate invasion processes by U. brizantha

Study objectives included determining whether prescribed burning affected ponderosa pine growth; mathematically modeling the growth response to burning; and determining whether forest management history affected growth response. I sampled 188 trees from two areas near Flagstaff, Arizona; one area (Brannigan Flat) had been logged and thinned, and the other (Chimney Spring) had not; both were burned in 1976. Within each study area, control and burned plots were of similar age, vigor, height, and competition index. Trees at Chimney Spring were older, less vigorous, and taller, and had a higher competition index than at Brannigan. For each tree, periodic basal area increment (PBAI) was calculated for the years 1974-1984. To determine which variable would best model growth, postfire PBAI (individual years, 1977-1984) was correlated with previous growth (average PBAI 1974-1976); crown ratio; competition index; thinning index; and diameter. Two models of growth response were developed; one oriented toward satisfying theoretical and research goals, and the other, toward management applications. Growth was modeled using stepwise multiple linear regression, and the dependent variable was postfire PBAI. Research Model independent variables were previous growth, years (climate), and treatment-year interaction, and 72% of total variance was explained. Fire affected growth significantly and negatively for two years, and then burned trees grew similarly to control trees. Management Model independent variables were crown ratio, competition index, crown ratio, subject tree diameter, year, and treatment, and 52% of total variance was explained. This model, too, indicated a slight negative effect of burning on growth. Management history was not a significant determinant of growth response. Both models validated well; the ratio of observed-to-predicted residual mean square was 1.04 and 0.91 (Research and Management Models, respectively). Thinning index was not significantly related to postfire growth, but a change in carbohydrate allocation from stem wood to crown and root expansion could have resulted in observed burning effects. Management implications include (1) short-term growth decline may result from burning, (2) management history did not affect growth response, and (3) burning impact is greatest in dense stands of small trees.