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The spatial pattern of plants reflects biotic and abiotic factors, including interactions with surrounding environmental conditions and other plants. Appalachian heath systems are presently understudied regarding spatial point pattern research, despite representing a unique and biologically valuable ecosystem. In this study, we characterized the spatial pattern of three tree species distributions in the upland heath barrens on Cabin Mountain in Canaan Valley, West Virginia through fieldwork, statistical modeling, and the use of geographical information systems (GIS). The research objectives were to: 1) quantify the global and local spatial patterns of trees to infer biotic process, and 2) identify how tree spatial pattern varies with selected biophysical variables, including ground curvature and topographic wetness index, to understand potential relationships between ambient conditions and spatial pattern. The spatial statistics, Ripley's K-function and nearest neighbor analysis, presented a series of different interaction types reflected across size-growth classes and species where the null hypothesis was rejected for some pairs and supported in others. The selected biophysical variables had no significant relationship to spatial pattern at the site. These findings suggest a range of both intraspecific and interspecific interactions are taking place in the heath barrens of Cabin Mountain, where significant levels of facilitation are occurring among encroaching red maple and striped maple, while red spruce is in competition with both species of maple, and that relationships are formed outside the influence of topographic characteristics of the site. / Master of Science / The spatial pattern of plants reflects biotic and abiotic factors, including interactions with surrounding environmental conditions and other plants. Appalachian heath barrens are presently understudied in regard to spatial point pattern research, despite representing a unique and biologically valuable ecosystem. In this study, we characterized the spatial pattern of three tree species in the red spruce heath barrens on Cabin Mountain in Canaan Valley, West Virginia through fieldwork, statistical modeling, and the use of geographical information systems (GIS). The research objectives were to: 1) quantify demographics and the spatial pattern of trees to assess for ongoing plant interaction, and 2) understand whether tree spatial pattern is affected by selected biophysical variables, including ground curvature and topographic wetness index, to understand potential relationships between environmental conditions and spatial pattern. The results suggested a range of interactions were occurring across the plot, intraspecies, different species-pairs, and size-growth classes. Most notably, encroaching striped and red maple species, had a positive relationship, while red spruce and both maple species had largely competitive relationships. Both topographic wetness index and ground curvature had no significant relationship to spatial pattern at the site. These findings suggest a range of both intraspecific and interspecific interactions are taking place in the heath barrens of Cabin Mountain, indicating the possibility of conversion from red spruce heath barrens to deciduous forest, that this pattern is formed outside the influence of topographic characteristics of the site.

With time going by, urban morphological structures of Beijing and Shanghai have dramatic changes during last decades. These changes often ignored by citizen, but have big influence for human daily life. And the changes of urban morphologies should be easily recognized by citizen. There are many previous comparative studies between these two Chinese cities, and these studies focus on types of areas, such as environment, traffic, city planning and cultures etc.. There are also many comparative studies about using space syntax theory and geometrical statistics to study urban morphologies. However, there are not direct comparison urban morphological study between Beijing and Shanghai, which from multiple perspectives. In order to gain a better understanding of urban morphologies, this thesis take street networks of two Chinese cites as a research object, based on space syntax theory, as well the combination of traditional geometrical statistics, comparative analysis methods to systematic quantitative analyze and comparative study the different street networks of urban space in Beijing and Shanghai. This project work analyzes hierarchy of axial lines, which automatically generated from street networks, to do a morphological comparison from topological perspective. And it analyzes frequency distribution of axial lines’ included angles and length of axial lines to study urban morphologies from geometrical perspective. Results in the project seem to empirical study that, the well-connected streets are minority part, which all most distributed in the sample cities’ ring structures and center areas. Street networks constitute an obvious regular grid pattern of Beijing and a curves pattern of Shanghai. Based on the hierarchical levels of street networks, research samples have same hierarchical levels but without the same number of street lines. The included angles of axial lines have an exceptionally sharply peaked bimodal distribution for both cities and number of most connected street’s length do not increase so much from ring1 to ring6 for Beijing, but they have much change for Shanghai.

Dieser Band gibt einen Einblick, welche flächenpolitischen Themen in den Gemeinden der Kernregion Mitteldeutschland mit welcher Intensität auf der Tagesordnung stehen. Es zeigt sich, dass die Herausforderungen durch den demographischen Wandel oder finanzielle Ressourcenknappheit erkannt wurden, dies sich aber derzeit nach Meinung des Projektverbundes noch nicht ausreichend in den gemeindlichen Handlungen widerspiegelt. Nachdem in Band 05 dieser Schriftenreihe die theoretischen flächenpolitischen Ziele unter Schrumpfungsbedingungen diskutiert wurden und eine Gegenüberstellung mit den gegenwärtigen normativen Aussagen der Landes- und Regionalplanung in der Kernregion Mitteldeutschland erfolgte, werden in diesem sechsten Band die gemeindlichen Entwicklungsperspektiven abgebildet. Grundlage für diese Auseinandersetzung ist eine schriftliche Befragung der Gemeinden, die Anfang 2008 durchgeführt wurde. Neben dieser quantitativen Erhebung erfolgten Vor-Ort-Gespräche mit Gemeindevertretern, die einige Aussagen des Fragebogens ergänzend erklärten. Mit den Ergebnissen in diesem Band wurde das Arbeitsmodul II des Projektes "REFINA KoReMi" abgeschlossen. Wir danken an dieser Stelle allen Gemeindevertretern, die sich die Zeit genommen haben, den Fragebogen umfassend auszufüllen bzw. für ein persönliches Gespräch zur Verfügung zu stehen. Durch diese engagierte Mitarbeit war es möglich, vertiefend in das Thema der gemeindlichen Sichtweisen zu flächenpolitischen Themen einzutauchen und den erarbeiteten theoretischen Zielen gegenüberzustellen.

The use of spatial statistics to investigate ecological processes in plant communities is becoming increasingly widespread. In diverse communities such as tropical rainforests, analysis of spatial structure may help to unravel the various processes that act and interact to maintain high levels of diversity. In particular, a number of contrasting mechanisms have been suggested to explain species coexistence, and these differ greatly in their practical implications for the ecology and conservation of tropical forests. Traditional first-order measures of community structure have proved unable to distinguish these mechanisms in practice, but statistics that describe spatial structure may be able to do so. This is of great interest and relevance as spatially explicit data become available for a range of ecological communities and analysis methods for these data become more accessible. This thesis investigates the potential for inference about underlying ecological processes in plant communities using spatial statistics. Current methodologies for spatial analysis are reviewed and extended, and are used to characterise the spatial signals of the principal theorised mechanisms of coexistence. The sensitivity of a range of spatial statistics to these signals is assessed, and the strength of such signals in natural communities is investigated. The spatial signals of the processes considered here are found to be strong and robust to modelled stochastic variation. Several new and existing spatial statistics are found to be sensitive to these signals, and offer great promise for inference about underlying processes from empirical data. The relative strengths of particular processes are found to vary between natural communities, with any one theory being insufficient to explain observed patterns. This thesis extends both understanding of species coexistence in diverse plant communities and the methodology for assessing underlying process in particular cases. It demonstrates that the potential of spatial statistics in ecology is great and largely unexplored.

This thesis investigates an informally self-organized street market, Porta Portese, in Rome, Italy. As a response to the contemporary phenomenon of migration, of people and goods, Porta Portese reflects the city’s evolving urban, cultural and social dynamics under the impact of global forces. Based on fieldwork executed from 2007-2009, this thesis builds on the idea of scoring in an attempt to establish a framework of tangible notations, using mediums ranging from time-lapse photography to pattern mapping. The language of architecture is adapted to render visible the spatial dynamics in the fabrication of the market. Despite its lack of representation, Porta Portese leaves its mark as a layer of the invisible city of Rome. One can trace its terrain through palpable memories of a collective urban and cultural experience, for it transports ideas, images and values between different worlds based on universal understandings. Ultimately, this thesis advocates for an interpretive representation of places like Porta Portese as valuable urban spaces that celebrate and satisfy the needs of direct human experience. This is achieved through enabling the neglected voice of a place that can strike a resonating chord of dialogue amongst differences - and it all begins from a story about Porta Portese.

This thesis investigates an informally self-organized street market, Porta Portese, in Rome, Italy. As a response to the contemporary phenomenon of migration, of people and goods, Porta Portese reflects the city’s evolving urban, cultural and social dynamics under the impact of global forces. Based on fieldwork executed from 2007-2009, this thesis builds on the idea of scoring in an attempt to establish a framework of tangible notations, using mediums ranging from time-lapse photography to pattern mapping. The language of architecture is adapted to render visible the spatial dynamics in the fabrication of the market. Despite its lack of representation, Porta Portese leaves its mark as a layer of the invisible city of Rome. One can trace its terrain through palpable memories of a collective urban and cultural experience, for it transports ideas, images and values between different worlds based on universal understandings. Ultimately, this thesis advocates for an interpretive representation of places like Porta Portese as valuable urban spaces that celebrate and satisfy the needs of direct human experience. This is achieved through enabling the neglected voice of a place that can strike a resonating chord of dialogue amongst differences - and it all begins from a story about Porta Portese.

Oaks (Quercus robur) are an important substrate for many epiphytic lichens, and with increasing age the bark of oaks becomes suitable for red-listed species. These species may respond to environmental and landscape factors differently, and at different spatial scales. We tested the effect of tree, environmental and land use factors on the occurrence and richness patterns of lichens species at various spatial scales (circles with radius ranging from 28 to 1225 m), in a heterogeneous landscape in South Eastern Sweden. The occurrence patterns of Cliostomum corrugatum and Chaenotheca phaeocephala were best explained by the density of oaks within radii of 400 and 302 m, respectively. In contrast, Ramalina baltica was best explained at smaller scale (263 m) as was species richness (302 m). This study shows that the most important factor for the occurrence and richness patterns of lichens was oak density at almost all the considered scales. Tree circumference also positively affected all four response variables.

The recent increase in large fires in southwestern forests has prompted concern regarding their ecological consequences. Recognizing the importance of spatial patterns in influencing successional processes, I asked: (1) How do large fires change plant communities?; (2) What are the implications of these changes for ponderosa pine forests?; and (3) What is the relationship of fire severity to gradients of climate, fuels, and topography? To address the first two questions, I studied succession in the woody plant community at two sites that burned in high-severity fire: La Mesa fire in northern New Mexico (1977) and Saddle Mountain in northern Arizona (1960). After large fires, abiotic conditions, associated prefire plant distributions, and spatial patterns of burning interacted to result in particular successional outcomes. Variation in abundance and diversity of species that spread from a refuge of seed sources remaining after the fire followed the model of wave-form succession. I investigated the implications of large fires for ponderosa pine by examining the influence of spatial patterns of burning on regeneration. Tree density corresponded most closely with particular scales of seed dispersal kernel and neighborhood severity metrics. Spatial patterns of burning remained influential even after consideration of variables describing subsequent burning and the physical and biotic environment. Age structure of young forests indicated that populations spread in a moving front and by long-distance dispersal. To explore the relationship between fire severity and climate, I investigated how the spatial heterogeneity of high-severity patches varied among 20 fires across gradients in fire size and climate. The largest fires generally occurred during cool dry La Niña climates, however, several fires deviated from this trend. Some spatial properties of severity did not correspond to fire size or to changes in climate. Characteristics of fuels and topography altered spatial patterns of severity, but interactions with extreme burning conditions may have disrupted these local influences in both La Niña and El Niño fires. Spatial patterns of fire severity are central to understanding ecological dynamics following large fires in southwestern forests. Moreover, simplistic assumptions regarding the relation of fire severity to fire size and climate should be viewed with caution.

Made available in DSpace on 2016-06-02T19:31:50Z (GMT). No. of bitstreams: 1 2972.pdf: 2337077 bytes, checksum: 982622dcacd1d28155dd375f4c73e974 (MD5) Previous issue date: 2010-03-05 / Financiadora de Estudos e Projetos / This study investigated the structure of spatial and ontogenetic stages of the species Pachystroma longifolium (Euphorbiaceae) in semideciduous forest in São Carlos, identifying and describing the post-germinative ontogenetic stages that characterize the development of the species, besides investigate whether the patterns allometric vary within and/or between ontogenetics stages. The spatial pattern was obtained using the aggregation index with the objective to check there are differences in spatial distribution pattern between ontogenetic stages and if these are determined by the preference of niches facilitators or arising from dispersion autochoric. In 1 ha were found 202 individuals and 4 ontogenetic stages were obtained: juvenile, immature, adult vegetative and reproductive adult. No seedlings were found in the plots and senile, which may be related to micro-environmental variation of the area or characteristics of the species. The branching pattern shown followed the Massart's architectural model, which is characteristic of species well adapted to low light conditions. All ontogenetic stages showed significant differences in height and diameter, indicating that they facing different environmental conditions and there is a great way allometric for each stage or group of stages, allowing for the best trade-off between stem diameter and height of plant. The population shows a patchy distribution, and the juveniles were those with the largest index of aggregation. Could not detect an effect of percentage of soil moisture on the distribution and density of individuals. As for the effect of percentage of canopy in the dry and rainy seasons, the correlation was positive and significant for the immature stage and the total of individuals in the area. The clustered pattern found for the population may be related both to autochoric dispersal strategies, as with the characteristics of the species. / O presente estudo investigou a estrutura de estádios ontogenéticos e espacial da espécie Pachystroma longifolium (Euphorbiaceae) na floresta estacional semidecídua, em São Carlos, identificando e descrevendo os estádios ontogenéticos pós-germinativos que caracterizam o desenvolvimento da espécie, além de investigar se os padrões alométricos variam dentro e/ou entre os estádios ontogenéticos. O padrão espacial foi obtido utilizando o Indíce de agregação com o objetivo de verificar se há diferenças no padrão de distribuição espacial entre os estádios ontogenéticos e se estas são determinadas pela preferência de nichos facilitadores ou decorrentes da dispersão autocórica. Em 1,0 ha amostrados encontramos 202 indivíduos distribuídos em 4 estádios ontogenéticos: juvenil, imaturo, adulto vegetativo e adulto reprodutivo. Não encontramos plântulas e senil nas parcelas, o que pode estar relacionado com a variação microambiental da área ou com características intrínsecas da espécie. O padrão de ramificação apresentado é próprio do modelo arquitetural de Massart, que é característico de espécies bem adaptadas às condições de pouca luz. Todos os estádios ontogenéticos apresentaram diferenças significativas em altura e diâmetro, indicando que estes enfrentam condições ambientais distintas havendo uma forma alométrica ótima para cada estádio ou conjunto de estádios. A população apresenta uma distribuição agregada, sendo que os juvenis foram os que apresentaram o maior Índice de agregação. Não foi possível detectar um efeito da porcentagem de umidade do solo sobre a distribuição e densidade dos indivíduos. Quanto ao efeito da porcentagem de cobertura de dossel na estação seca e chuvosa, a correlação foi positiva e significativa para o estádio imaturo e para o número total de indivíduos presentes na área. O padrão de distribuição agregado encontrado para a população pode estar relacionado tanto com estratégias de dispersão autocórica, quanto com características intrínsecas da espécie.