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.

Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [100]-113).

To understand maintenance of the within-habitat diversity of closely related species, I investigated 11 Carex species growing along rivers in the south-western St. Lawrence Valley of Quebec. Microenvironments within a half meter of focal plants characterized for Carex comosa, C. crinita, C. grayi, C. intumescens, C. lacustris, C. lupulina, C. pseudocyperus, C. retrorsa, C. tuckermanii, C. typhina, and C. vesicaria revealed significant differences among the species in their environmental affinities. Species appear to fall into groups based on their tolerance of flooding and are secondarily differentiated on other environmental gradients such as insolation, soil pH and soil organic matter. Several traits were related to the environments that species inhabit: diaspore weight, diaspore floating duration, and root aerenchyma. The absence of any phylogenetic trend in niche differences for pairs of species supports the idea that evolutionary differentiation of the alpha-niche is the basis for coexistence of congeners.

Thesis (M.S.)--Western Washington University, 2008. / Includes bibliographical references (p. 116-128). Also available online.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [235]-251).

Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 82-92).

Members of a guild of cursorial spiders (Pardosa spp. and Alopecosa spp.) spatially segregated among five discrete habitats, from a streamside cobble habitat grading laterally along a successional gradient to the leaf litter zone of a transition or climax riparian forest. Seasonal activity peaked in midsummer for all guild members. Spiders were active diurnally earlier in the streamside habitats, and levels of activity were positively correlated with light intensity. Guild members Pardosa tristis and Pardosa uncata were most different in habitat selection and periods of diurnal activity. Males and females of all guild species differed in their distribution among habitats and over months of collection. Measures of guild species diversity and evenness were variable between habitats, and were largely influenced by the relatively high abundance of one or two guild species, particularly in the streamside habitats.

No description available.

Competition for resources and other interference from non-crop vegetation often limits the productivity of pine and pine-hardwood forest stands in the southern United States. However, forest researchers have yet to fully quantify the effect of this interference on forest tree yield and there is an incomplete understanding of the biological mechanisms of interference. To better quantify the effects of interference interactions and elucidate their mechanisms, a field replacement series experiment and two supporting greenhouse experiments were carried out using loblolly pine (Pinus taeda L.), red maple (Acer rubrum L.), black locust (Robinia pseudoacacia L.), and herbaceous vegetation. Interference between pine. hardwood species, and herbaceous vegetation significantly impacted the growth and yield of young experimental pine-hardwood stands. While herbaceous vegetation significantly affected all stands. it reduced the yield of hardwood species more than loblolly pine. Loblolly pine appeared to ameliorate the effect of herbaceous vegetation on hardwoods in some stands. Interference outcomes were site- and scale-dependent. In field stands, synergistic adjustment in total yield due to pine-hardwood interference was not observed, except for loblolly pine-black locust mixtures on lower site quality replicates. Hardwood species suppressed the growth of pine in seedling stands planted at very close spacing in greenhouse boxes, while the yield at age three of less densely-planted field stands was positively related to the proportion of pine in the stand. Close spacing increased the ability of wide-spreading hardwood crowns to overtop and restrict light availability to conically-shaped pine crowns. Interference outcomes were related to the interactive effect of light, soil moisture, and soil nitrogen resources on tree growth and competitive ability. If not overtopped by hardwoods, loblolly pine had high yields in mixtures with hardwoods and competed effectively for soil moisture and nitrogen through efficient use of these resources. Changes in allometric relationships were observed for tree species in response to interference including root-shoot ratios, crown dimensions, and specific leaf areas. Tall fescue (Festuca arundinacea Schreb.), the principal herbaceous species in the field study, appeared to affect the physiology and yield of all species through allelopathy in a greenhouse experiment. suggesting that reduced yield in herbaceous plots may be due to direct chemical effects in addition to resource competition. / Ph. D.

I sampled bird densities and habitat characteristics along a gradient from a second-order stream to 454 m upland at 16 locations. Total bird density, species richness, and densities of 28 bird species were tested to determine whether riparian habitats influenced bird communities. Total bird density and species richness showed no riparian influence. Acadian flycatchers and Louisiana waterthrushes were closely linked to the streams. Carolina wrens, American robins, and red-eyed vireos showed weaker but positive associations with the streams. Eastern wood-pewees, black-and-white warblers, pine warblers, worm-eating warblers, and scarlet tanagers demonstrated a negative association with streams. A cluster analysis was used to group the 28 bird species into 5 assemblages based on their distribution among the sampling stations. The species were classified as belonging to the following assemblages: riparian, upland forest, mesic hardwoods, xeric forest, and mature hardwoods generalist. Logistic models were developed to predict the number of species in each assemblage that were present and the presence of each species at each station based on the habitat characteristics at the site. Regression models were developed to predict the relative abundance of each assemblage and species at occupied stations. / Master of Science