Historically wildfires have been beneficial to forests, however, human developments have encroached on forests when wildfire was artificially suppressed by federal and state agencies. The area burned by wildfire each year has increased twenty-fold in the past three decades. Large, high severity fires pose increased threats to human and aquatic communities within and downstream of the burned area due to post-wildfire effects on flooding and sedimentation. We need to understand the impacts of wildfires to be able to mitigate their damages and to recognize their potential benefits. This research addresses the questions: 1) Do wildfires impact rural and urban economies differently and what are managers doing to adapt management strategies? 2) Do floods increase after wildfire, and if so, by how much? 3) Do wildfires affect fish habitat, and if so, how? Chapter 2 provides insight into both positive and negative economic impacts on rural and urban economies after a wildfire, and brings to light manager’s inability to change their management strategies due to constraints such as budget limitations. Chapter 3 measures how floods change in nine basins after a wildfire occurred, and reveals that floods may increase up to 880 percent after a fire. Chapter 4 demonstrates that fish habitat is significantly altered after wildfires and why change is harmful to the fish. This work shows that wildfire significantly changes the burned and surrounding area, and that more work is needed for a better understanding of how to predict how a specific area will respond to wildfire.

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Changes in the bed of Geum River (L=130 km from Daechung regulation dam to Geum River estuarial bank) in South Korea were predicted using the 1-D HEC-RAS model and the 2-D CCHE2D model. Three movable weirs have been installed and dredging has been carried out in Geum River under the Four Major Rivers Restoration Project (2009-2012). Inflow data of sub basins were calibrated with daily runoff data generated by PRMS based on a hydrologic unit map. To determine the gate opening height for maintaining the management water level, unsteady analysis was performed using HEC-RAS. Thereafter, long-term riverbed changes through quasi-unsteady analysis were simulated for 20 years. In order to investigate the effect of movable weirs, sediment analysis was done for three cases of gate opening: case 1 is fully close, case 2 is fully open, and case 3 is regulating gates by the operating rule. Also, short-term riverbed changes were predicted with CCHE2D for 11 days in the problem area, depending on the results of 1-D model, and the effect of dikes was examined. In future, gate operation and structural methods such as dikes must be in step with each other in order to manage sediment and rivers in an ecofriendly manner.

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This semestral thesis deals with the creation of a laboratory exercise for the course of Communication Technology. This course is designed for Teleinformatics in bachelor's degree program and should provide students with basic knowledge of network protocols and technologies. For this reason, the thesis deals with basic transport protocols, protocols for transmission via backbone networks and network layer protocols. The introductory part introduces the OPNET design environment, more precisely its free version of Riverbed Modeler Academic Edition 17.5, where the design of the laboratory exercises is done. The second part is a necessary theory to the exercises. The lab exercise is focused on differences in TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) protocols. The second laboratory exercises is focused on technologies for transmission mainly on WAN (Wide Area Network) namely ATM (Asynchronous Transfer Mode) and Frame Relay. The last proposed exercises deals with the two most prominent Internet protocols that are used for communications IPv4 (Internet Protocol version 4) and IPv6 (Internet Protocol version 6) protocols. Guides for students have been created for this task, and at the end of each part, the complementary tasks and questions are given to students in oder to test the gained knowledge of the discussed issues.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Brazilian environmental legislation, in what it refers to natural resource preservation, has its central point in the Forestry Code. This is a set of definitions and rules to be obeyed in both rural and urban environments, in view of the fact that one of its main tools happens by APP s (Permanent Preservation Areas). The new Forest Code (NCF) which repeals Law No. 4,771, Old Forestry Code (ACF), regulates the definition of APP s of waterway marginal ranges, considering that currently their delimitation must be done from the edge of the regular bed rail (LR), differently from the ACF, which indicated the APP range beginning from the larger hydrological river bed (LMH). The objective was to compare the application of the new APP delimitation law in river ciliary range, opposite to the Old Code, as well as the difference between themselves, in a typically rural basin. The Arroio Grande was used as a case study, the extent of the LR was defined, as well as of LMH and its respective APP range, thus, forming the Permanent Protection Range (FPP) for the stretch of defined river. Within each protection strip, it was utilized the land use analysis and also its commonest conflicts that define the boundaries of the APP defining bed. Through the maps which were obtained, the APP of this stretch of the Arroio Grande currently must be 50m from the LR rail, which is bounded through this river, and includes river shores and islands. About the change in the legislation, it is highlighted that the alteration of the beginning of APP range from LMH to LR brought loss of the protected area. The NCF brings as a contribution to permit the owners the adequacy of degraded areas using a minor range of preservation and facilitating the definition of LR by satellite images. According to the NCF, 22.3%of the APP areas of the Arroio Grande are not protected, which compromises the basin balance when we see the importance of these sites for the ecosystem maintenance. Thus, one can compare the laws through the maps and conclude that the NCF has brought some progress such as the ease in the demarcation of APP, but it is milder compared to the size of the protected area. This way one indicates that the Forestry Code is applied to a larger possible number of properties for both proposed purposes in its text: environmental preservation and recovery, with owners awareness about the importance of protecting riparian bands for maintenance of system stability, or its recovery. / A legislação ambiental brasileira, no que se refere à preservação dos recursos naturais, tem seu ponto central no Código Florestal. Trata-se de um conjunto de normas para conservação dos recursos naturais, tanto no ambiente rural como urbano, sendo que uma das suas principais ferramentas se dá por meio das APP s (Áreas de Preservação Permanente). O Novo Código Florestal (NCF), que revoga a Lei n° 4.771, Antigo Código Florestal (ACF), regulamenta a definição de APP s das faixas marginais dos cursos d água, sendo que atualmente sua delimitação deve ser feita a partir da borda da calha do Leito Regular (LR), diferentemente do ACF, que indicava o início da faixa de APP a partir do Leito Maior Hidrológico (LMH) do rio. Objetivou-se comparar a aplicação da nova lei de delimitação de APP s em faixa ciliar de rio frente ao antigo Código, bem como a diferença de área dos mesmos, em uma bacia tipicamente rural. Utilizou-se como estudo de caso o Arroio Grande, definindo-se a extensão do LR, do LMH e respectiva faixa de APP, formando assim, a Faixa de Proteção Permanente (FPP) para o trecho de rio definido. Dentro de cada faixa de proteção, foi realizada a análise do uso do solo e dos conflitos mais comuns encontrados para delimitação do leito definidor da APP. Por meio dos mapas obtidos, atualmente, a APP deste trecho do Arroio Grande deve ser de 50 metros a partir da calha do LR, que se trata da calha delimitada do rio, incluídas as praias fluviais e ilhas fluviais. Sobre a mudança na legislação, destaca-se que a alteração do início da faixa de APP do LMH para o LR trouxe perda de área protegida. O NCF traz como contribuição permitir aos proprietários a adequação das áreas degradadas com uma faixa menor de preservação, e facilitar a definição do LR por meio de imagens de satélite. Segundo o NCF, 22,3% das áreas de APP do Arroio Grande não estão protegidas, o que compromete o equilíbrio da bacia, visto a importância que estes locais possuem para manutenção do ecossistema. Assim, pode-se comparar as legislações através dos mapas e concluir que o NCF trouxe alguns avanços, como a facilidade na demarcação da APP, mas é mais brando em relação ao tamanho de área protegida. Indica-se desta forma que o Código Florestal seja aplicado a um maior número possível de propriedades para ambas as finalidades propostas em seu texto, de preservação e recuperação ambiental, com conscientização dos proprietários da importância da proteção das faixas ripárias para a manutenção da estabilidade do sistema, ou recuperação da mesma.

The seed bank dynamics of five habitats as well as a grazing gradient in the southwestern Kalahari, South Africa were studied. Soil samples were collected in the following habitats: dune crests, dune slopes, dune streets, a calcrete outcrop and a riverbed on the farm Alpha. Soil samples were also collected along a grazing gradient from a watering point. Three methods of soil seed bank analysis were used to analyse the soil samples and to gain insight into soil seed bank response to habitat type and to grazing pressure, over four seasons in the year 2004. Results from the three methods of analysis were also compared to each other. They included the direct seedling germination method, the seedling germination re-examination and the seed extraction method. These analyses were used to (a) estimate seed bank size and composition in response to habitat type and grazing pressure; (b) the differences between the standing vegetation- and the seed bank-flora in different habitats and along a grazing gradient and (c) the type of seed banks that tend to form in certain habitats and in response to grazing pressure. Analyses of soil seed bank size along a grazing gradient showed that the seedling emergence re-examinations estimated a larger size for the seed bank than the direct seedling emergence method. The seed extraction method estimated a significantly larger seed bank size than the other two methods. Heavy grazing pressure favoured annual/opportunistic species such as Schmidtia kalahariensis, which formed very large seed banks in heavily trampled areas. When Schmidtia kalahariensis data was removed from the seed bank analyses, it was found that, in contrast to previous results, the direct germination method mostly estimated a larger seed bank size than the re-examination. Also, the estimation of seed bank size by the flotation method, in this case, was much smaller. The flotation method produced data mostly for hard-seeded species, while the seedling emergence method produced data for species with small seeds and which were readily germinable. In all seasons, the dune crest habitat always had the smallest seed bank and the riverbed habitat always had the largest seed bank. All the dune habitats were characterised by perennial grasses. Perennial grasses formed transient seed banks which were relatively small. The riverbed habitat’s vegetation was mostly composed of annuals. Annual plants formed persistent seed banks which were relatively large. Species richness of the readily germinable seed bank in all habitats, fluctuated between the four seasons and was usually largest in summer. The difference in species richness between the above- and belowground floras fluctuated over four seasons. The dune habitats showed a large difference between the species richness of the above- and the below-ground flora, while the riverbed habitat showed a much smaller difference. The dune habitats had many species with transient seed banks while the riverbed was characterised by many species with short-term persistent and ‘permanent’ seed banks. / Dissertation (MSc)--University of Pretoria, 2011. / Plant Science / unrestricted

The size and organization of bed material, bed texture, is a fundamental attribute of channels and is one component of the physical habitat of aquatic ecosystems. Multiple discipline-specific definitions of texture exist and there is not a universally accepted metric(s) to quantify the spectrum of possible bed textures found in aquatic environments. Moreover, metrics to describe texture are strictly statistical. Recreational-grade side scan sonar systems now offer the possibility of imaging submerged riverbed sediment at resolutions potentially sufficient to identify subtle changes in bed texture with minimal cost,expertise in sonar, or logistical effort. However, inferring riverbed sediment from side scan sonar data is limited because recreational-grade systems were not designed for this purpose and methods to interpret the data have relied on manual and semi-automated routines. Visual interpretation of side scan sonar data is not practically applied to large volumes of data because it is labor intensive and lacks reproducibility. This thesis addresses current limitations associated with visual interpretation with two objectives: 1) objectively quantify side scan sonar imagery texture, and 2) develop an automated texture segmentation algorithm for broad-scale substrate characterization. To address objective 1), I used a time series of imagery collected along a 1.6 km reach of the Colorado River in Marble Canyon, AZ. A statistically based texture analysis was performed on georeferenced side scan sonar imagery to identify objective metrics that could be used to discriminate different sediment types. A Grey Level Co-occurrence Matrix based texture analysis was found to successfully discriminate the textures associated with different sediment types. Texture varies significantly at the scale of ≈ 9 m2 on side scan sonar imagery on a regular 25 cm grid. A minimum of three and maximum of five distinct textures could be observed directly from side scan sonar imagery. To address objective 2), linear least squares and a Gaussian mixture modeling approach were developed and tested. Both sediment classification methods were found to successfully classify heterogeneous riverbeds into homogeneous patches of sand, gravel, and boulders. Gaussian mixture models outperformed the least squares models because they classified gravel with the highest accuracies.Additionally, substrate maps derived from a Gaussian modeling approach were found to be able to better estimate reach averaged proportions of different sediments types when they were compared to similar maps derived from multibeam sonar.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18571号 / 工博第3932号 / 新制||工||1604(附属図書館) / 31471 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 角 哲也, 教授 藤田 正治, 准教授 竹門 康弘 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

No description available.