Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 136-151).

Thesis (Ph.D.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Andrew Hansen. Includes bibliographical references.

Thesis (M.S.)--Texas State University-San Marcos, 2006. / Vita. Appendices: leaves 23-46. Includes bibliographical references (leaves 47-54).

Thesis (M.S.)--Texas State University-San Marcos, 2006. / Vita. Appendices: leaves 23-46. Includes bibliographical references (leaves 47-54).

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Orientadores: João Vasconcellos Neto, Gustavo Quevedo Romero / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-18T01:27:37Z (GMT). No. of bitstreams: 1 Diniz_Suzana_M.pdf: 61632938 bytes, checksum: 7bcbe079e28a7f57357c4d6ecbb16e88 (MD5) Previous issue date: 2011 / Resumo: A estrutura do hábitat tem sido um tema recorrente na literatura, havendo diversos estudos que correlacionaram uma maior complexidade estrutural do hábitat à riqueza e abundância dos mais variados taxa. Contudo, este é um tema de difícil generalização e as abordagens experimentais ainda são raras. A vegetação é um elemento que proporciona complexidade estrutural ao hábitat devido às diversas organizações arquiteturais de seus módulos. Diversos estudos demonstraram que os artrópodes associados às plantas são um dos grupos mais afetados pela arquitetura da vegetação, particularmente as aranhas. Logo, o objetivo deste estudo foi avaliar os possíveis efeitos da arquitetura da vegetação sobre a abundância e riqueza de guildas de artrópodes, com ênfase na comunidade de aranhas. O estudo foi dividido em duas partes: (1) uma pesquisa exploratória, cujo objetivo foi correlacionar diferentes elementos arquiteturais das plantas com a comunidade de artrópodes, de forma a avaliar se determinados grupos de artrópodes são mais ou menos abundantes em determinadas configurações arquiteturais da vegetação; (2) uma pesquisa experimental, cujo objetivo foi manipular a arquitetura vegetal agrupando e espaçando os ramos vegetativos, de forma a avaliar os efeitos da densidade vegetal sobre a comunidade de artrópodes. Um total de 17 espécies de plantas e oito características arquiteturais foi utilizado na pesquisa exploratória. Já o experimento foi feito para três espécies de plantas e repetido em duas estações climáticas diferentes (seca e chuvosa) para avaliação dos efeitos sazonais sobre a resposta da comunidade de artrópodes à manipulação arquitetural da vegetação. Todos os dados de abundância e riqueza de artrópodes foram expressos por unidade de biomassa de planta e a disponibilidade de presas para os predadores (i.e., o total de artrópodes exceto o grupo de predadores sendo estudado) foi colocada como co-variável. Os padrões de abundância da comunidade de aranhas foram fortemente correlacionados à arquitetura da vegetação, tanto na pesquisa experimental quanto na exploratória. Já as guildas de outros artrópodes, com algumas exceções, foram pouco afetadas pela arquitetura da vegetação. Algumas guildas de fitófagos tiveram padrões consistentes de distribuição em plantas com diferentes arquiteturas. Estes padrões, por sua vez, ocorreram tanto na pesquisa exploratória quanto na experimental. A abundância de parasitóides e predadores (exceto aranhas) foi mais explicada pela disponibilidade de presas do que pela arquitetura per se. O padrão de distribuição das aranhas sobre as plantas pode ser explicado, em grande medida, pelo favorecimento que determinadas arquiteturas proporcionam aos hábitos de forrageio de cada guilda. Já o padrão de abundância das guildas de fitófagos em plantas com diferentes arquiteturas provavelmente decorre de uma modulação da taxa de predação, uma vez que a arquitetura da planta está vinculada à disponibilidade de refúgios / Abstract: Habitat structure has been a recurrent subject in literature and there have been several researches that correlated a greater structural complexity of habitat to the richness and abundance of diverse taxa. However, this represents a subject of hard generalization and experimental approaches are still rare. Vegetation is an element that provides structural complexity to habitat due to diverse architectural organization of their modules. Many researches demonstrated that arthropods associated to plants are one of the most affected groups by the vegetation architecture, especially the spiders. Thus, the objective of present research was to evaluate possible effects of vegetation architecture on the richness and abundance of arthropod guilds, with special emphasis on spider community. The research was divided in two parts: (1) a survey research, whose objective was to correlate diverse architectural traits of plants with the arthropod community, this in order to assess whether certain groups of the arthropod community are more or less abundant in certain plant architectural configurations; (2) an experimental research, whose objective was to manipulate plant architecture by grouping and spacing the vegetative branches in order to evaluate the effects of plant density on the arthropod community. A total of 17 plant species and eight architectural traits was used in survey research, whereas the experiment was performed in three plant species and repeated in two seasons (dry and wet) for evaluation of seasonal effects on the arthropod community response to manipulation of the plant architecture. All data referring to arthropod abundance and richness were given per unit of plant biomass and the prey availability for predators (i.e., all arthropods except the group of predators being studied) was set as a covariate. The abundance patterns of spider community were strongly correlated to the plant architecture, both in experimental and in survey research. Nevertheless, the other arthropod guilds, with some exceptions, were weakly affected by vegetation architecture. Some phytophagous guilds had consistent patterns of distribution on plant with different architectural traits. These patterns, by the way, occurred as in survey as in experimental research. The abundance of parasitoids and predators (except spiders) was more explained by the prey availability than by the plant architecture per se. Patterns of spider distribution on plants can be quite explained by the advantages that some plant architectures provide to the foraging habits of each guild. Abundance patterns of phytophagous guilds on plants with different architectural traits, nevertheless, were probably due to modulation of predation rates, since the plant architecture could determine refuge availability / Mestrado / Mestre em Ecologia

Orientador: Fosca Pedini Pereira Leite / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T11:20:12Z (GMT). No. of bitstreams: 1 Bueno_Marilia_D.pdf: 1421870 bytes, checksum: 37eb3d9230e7741798f121407dee5d97 (MD5) Previous issue date: 2015 / Resumo: Algas calcáreas articuladas estão presentes em costões rochosos ao redor do mundo e formam densos tapetes, os quais abrigam uma fauna muito rica de invertebrados. Dentre eles, os anfípodes são dominantes e sua associação com estas algas foi investigada. Inicialmente foi feita a caracterização do habitat. A biomassa das algas e a abundância total dos anfípodes não diferiram entre as estações do ano, já a composição de espécies de anfípodes apresentou variação, a qual foi atribuída principalmente ao padrão de ocorrência de duas espécies de hialídeos, Apohyale media e Hyale niger, que são dominantes nas algas calcáreas. A biomassa das algas também não variou conforme exposição à ação de ondas. Diferenças na abundância total dos animais foram observadas, sendo encontrados mais animais nos costões mais expostos às ondas. Neste tópico, os tanaidáceos foram incluídos e apenas duas espécies foram encontradas, cada uma associada à um grau de exposição à ação de ondas. Leptochelia aff. dubia foi encontrada apenas nos costões abrigados, enquanto Zeuxo coralensis apenas em costões expostos. Os tapetes de algas coralinas são verticalmente extensos a ponto de terem características físicas (quantidade de sedimento e tamanho de grãos) e biológicas (abundância e composição de espécies de anfípodes) distintas entre as zonas superior e inferior do mesmo tapete. Após a caracterização do habitat, sua utilização pelos anfípodes foi examinada com relação à estrutura (arquitetura) das algas, a altura de ocorrência das algas no costão rochoso e o papel do sedimento na seleção deste habitat. O volume intersticial foi extremamente variável dentre as cinco algas estudadas entretanto, para todas as algas, quanto maior o volume intersticial, maior a abundância dos anfípodes. O habitat formado pelas coralinas, independente da altura no costão, parece ser o fator mais importante na seleção pelos anfípodes. Com relação ao sedimento, sua retenção nos tapetes de algas não se mostrou sazonal e não foi observada relação com a abundância dos anfípodes. Os experimentos de laboratório corroboraram o padrão observado em campo e não indicaram um importante efeito da adição do sedimento na seleção de habitat pelos hialídeos. A malha intrincada formada pelas frondes das algas calcáreas permite a retenção, além do sedimento e da matéria orgânica associada à ele, de diferentes tipos de alimento como microalgas e componentes da meiofauna. Essa gama de itens alimentares pode ser importante na seleção deste local pelos anfípodes, já que a alimentação da alga em si não ocorre, e explicaria a grande variedade de hábitos alimentares apresentados pelos anfípodes associados. A seleção do habitat de coralinas pode também estar relacionada à proteção contra a dessecação, já que retenção de água entre as frondes mantém o ambiente úmido nos períodos de emersão / Abstract: Articulated calcareous algae are distributed on rocky shores worldwide forming dense mats and harboring rich invertebrate assemblages. Amphipods are dominants and their association with coralline algae was investigated. First, the habitat characterization was done. Algae biomass and amphipods abundance did not differ among seasons, but species composition showed a variable pattern mainly in response to occurrence patterns of the dominant hyalids Apohyale media and Hyale niger. Algae biomass did not vary between degrees of wave exposure, however, more amphipods were found at exposed shores. Tanaids were included and an interesting spatial segregation was observed. Only two species were found, each one associated to a degree of wave exposure. Leptochelia aff. dubia was found at sheltered shores, while Zeuxo coralensis at exposed shores. Coralline mats are wide enough to have distinguished upper and lower zones based on physical (amount of sediment and grain size) and biological (amphipods abundance and species composition) features. After characterizing the habitat, its usage by the amphipods was examined through algae structure (architecture), height on shore and the effect of sediment loads on habitat selection. Interstitial volume was highly variable among the five algae studied and a strong positive relation between interstitial volume and amphipods abundance was observed. Coralline habitat, regardless of the height on shore, was probably the main factor governing habitat selection. Sediment retention at coralline mats was not seasonal and no relation with the amphipods was found. Laboratory experiments corroborate the observed field patterns and added sediment had no effect on habitat selection by the hyalids. The intricate canopy of coralline algae allowed retention, not only of sediment and organic matter, but also of microalgae and meiofauna. This wide array of food items may be important for coralline habitat selection by the amphipods, since they do not feed on coralline itself. In this case, coralline could be an important source of food, allowing the coexistence of amphipods having different feeding habits. Water retention may also play an important role, since habitats are maintained humid during emersion periods / Doutorado / Ecologia / Doutora em Ecologia

This document contains three manuscripts, each forming a separate chapter. The first chapter is a sensitivity analysis, conducted on a wildlife habitat analysis system previously described. This was designed to mathematically test the effects of changing various parameters used in the system on the calculation of specific indices that this system measures. Chapters 2 and 3 represent specific applications of the proposed habitat analysis system. Each has been submitted to appropriate professional journals. All three chapters are self-contained. / M.S.

Pellet group surveys were conducted on 21 transects in February-March, 1985, and January-March, 1986, to estimate relative deer densities on eleven study areas on the Jefferson National Forest, southwestern Virginia. Habitat data were collected on the same transects in July-September, 1985. Additional habitat information was measured from aerial photographs and USDA Forest Service compartment maps. These data were used to develop eleven multiple linear regression models and one pattern recognition (PATREC) model for predicting deer winter habitat quality, based on the assumption that relative density of deer is a good indicator of habitat quality. The densities of evergreen broad-leaved shrubs and"Nonforage" shrubs, basal area, mean distance to a field, and percent slope were among the most important variables selected in the regression model building process. Six variables were selected for use in the PATREC model: mean tree diameter, oak basal area, basal area of"Other Winter Forage" tree species, density of"Nonforage" shrubs, mean distance to a gated gravel road, and mean canopy closure. Spearman's rank correlations were used to compare the model outputs with estimated pellet group densities. All of the models had correlation coefficients ≥ 0.60, four had correlation coefficients > 0.80. The models need to be validated, i.e. tested with independent data from areas outside the study sites. These tests will help refine the models and assess their effectiveness in other regions of the southern Appalachian Mountains. / Master of Science

I measured habitat characteristics at 21 barred owl, 30 northern goshawk. and 17 redshouldered hawk nest areas, and at 49 random areas within a 780 km2 area in northwest Connecticut. Measurements were taken at a macro ground level and from 1:12,000 and 1:40,000 black and white and 1:58,000 and 1:126,000 color infrared aerial photography. Among-species nest area analyses at the ground level indicated that higher beech and red maple densities were associated with red-shouldered hawk nest areas than with nest areas of barred owls or northern goshawks. Analyses between species and random areas indicated that barred owl nest areas had higher sugar maple density and basal area than random areas. Denser canopy, greater tree density and basal area, a greater percentage of forested land, and greater hemlock density were associated with nest areas of both northern goshawks and red-sl1ouldered hawks. Northern goshawk nest areas had higher red maple and conifer densities and were found farther from human activity and forest openings than random (available) habitat. Red-shouldered hawk nest areas had higher beech and deciduous tree densities and basal areas than expected based on available habitat. Six of 21 habitat characteristics measured from 4 scales of aerial photography were significantly different either among species nest areas or between species and random areas. Northern goshawks nested in areas with little open water. Red-shouldered hawks had higher percentages of open water near nest sites and were significantly closer to water than available habitat. Four variables related to contiguity of the forest were Significant in the analyses. The greatest number of cover type patches generally was associated with random areas followed by barred owl then redshouldered hawk nest areas. Red-shouldered hawks and northern goshawk nest areas were in relatively contiguous tracts of forested land and farthest from forest openings. The highest percentages of agricultural and non-forested land were found at random areas and barred owl nest areas, with lowest percentages at red-shouldered hawk and northern goshawk nest areas. The percentage of open water and swamp were most easily identified and measured from 1:58,000 color infrared aerial photography. Distance to water was most consistently measured from 1:58,000 CIR or 1:40,000 B&W aerial photography. The distance to opening was measured most consistently from the 1:12,000 scale. The 1:40,000 and 1:12,000 scales of aerial photography provided the most consistent measurements of the percentages of agricultural and non-forested land. / Master of Science