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1	Relationships between tributary catchments, valley-bottom width, debris-fan area, and mainstem gradient on the Colorado Plateau: A case study in Desolation and Gray Canyons on the Green River Elliott, Caroline M. 01 May 2002 (has links) The alluvial forms of the rivers that drain the Colorado Plateau are a product of the water and sediment load that tributaries deliver to the trunk streams. Where the Green and Colorado Rivers cross structural barriers, narrow canyons have been incised. In the steep terrain adjacent to many of these canyons debris flows occur in the catchment basins of tributaries and deliver coarse sediment to the mainstem river corridor. Over time, debris flow deposits have aggraded in trunk stream valleys and created landforms known as debris fans. The sizes of these debris fans are related to the accommodation space available for fan formation. Lithologic variation in the layer-cake stratigraphy of the Colorado Plateau has led to varying valley widths. Tributary catchment, debris fan, depositional site, and mainstem river characteristics are examined over the 156-kilometer reach of the Green River through Desolation and Gray Canyons. Desolation and Gray Canyons provide some of the widest valley widths and resultant debris fan areas on the Colorado Plateau. tributary catchments valley-bottom width debris-fan area mainstem gradient Geology
2	Using Classification and Regression Tree and Valley Bottom Modeling Techniques to Identify Riparian Vegetation in Pinal County, Arizona Hickson, Benjamin 01 January 2015 (has links) The ecological value and functionality of riparian systems along ephemeral, intermittent, and perennial streams in the Southwest is well established. In Pinal County, Arizona the existing datasets available to environmental managers and governing bodies drastically underestimate the extent and presence of riparian zones. This study addresses the issue through the use of remote sensing land cover classification techniques. Landsat 8 data, topographic data, and high-resolution color infrared (CIR) imagery, and several derived vegetation indices are used to construct a classification and regression tree (CART) model. Using training data, the CART model is used for the identification and delineation of basic land cover classes across the County. Woody annual and perennial species are identified and associated to riparian zones using a valley bottom model (VBM) developed by the United States Department of Agriculture. The CART model (kappa value of 0.76) found that 929 square-miles of annual vegetation and 651 square-miles of perennial vegetation are present across Pinal County. Annual and perennial vegetation classifications are assessed for density using a 0.33 acre moving window. The density values for both classes are then used in conjunction to differentiate upland, xeroriparian, mesoriparian, and hydropriarian vegetation zones. Vegetation zones are clipped to regions where the VBM identifies valley bottom probability to be 62 percent or greater. The results generated provide a sufficiently comprehensive dataset that gives County managers and environmental professionals improved insight into the presence and distribution of important riparian habitats. riparian Regression analysis valley bottom Arizona -- Remote sensing. CART Vegetation Mapping
3	Potencialidades socioambientais das áreas de preservação permanente em fundos de vales urbanos: proposição de método expedito de análise Netto, Milton Pavezzi 14 June 2013 (has links) Made available in DSpace on 2016-06-02T20:00:56Z (GMT). No. of bitstreams: 1 6060.pdf: 4715953 bytes, checksum: 3917e03dd21ad92a86c712911c1459e7 (MD5) Previous issue date: 2013-06-14 / Universidade Federal de Minas Gerais / Guided by the questions about the effectiveness of strategies for environmental protection in cities, this research was aimed at structuring a fast method to analyze the social and environmental potential of PPAs in urban valley bottoms able to provide information to support the recovery and/or maintenance of the environmental quality of these areas in compatibility with existing social dynamics in the built space For structuring method, physical variables and criteria involved in the environmental quality of valley bottoms and representative forms of human occupation at these sites were raised. Based on these variables, we designed a scoring system that indicates the level of compliance with environmental functions of PPAs in urban valley bottoms and indicates the favorable and unfavorable conditions to fulfill these functions. The method was applied in two urban sources in the city of São Carlos, with distinct characteristics and land use in the buffer corresponding to the PPA. in the context of urban planning, the results of the application shows that the method has potential both to provide information that supports immediate or short-term decisions as to guide the application of other diagnostic decisions in the medium and long term. / Pautada pelo questionamento sobre a efetividade das estratégias ambientais de proteção territorial nas cidades, esta pesquisa teve como objetivo a estruturação de um método expedito de análise das potencialidades socioambientais das APPs em fundos de vales urbanos capaz de fornecer informações para subsidiar a recuperação e/ou manutenção da qualidade ambiental destas áreas em compatibilidade com as dinâmicas sociais existentes no ambiente urbanizado. Para a estruturação do método, foram levantadas variáveis físicas e critérios de análise intervenientes na qualidade ambiental dos fundos de vales e representativos das formas de ocupação antrópica nestes locais. Baseando-se nestas variáveis, foi elaborado um sistema de pontuação que indica o nível de cumprimento das funções socioambientais no trecho analisado e indica as condições favoráveis e desfavoráveis ao cumprimento destas. O método foi aplicado em duas nascentes urbanas na cidade de São Carlos, com características distintas de uso e ocupação do solo na faixa correspondente à APP. Os resultados da aplicação demonstraram que, no contexto do planejamento urbano, o método apresenta potencial tanto para fornecer informações que subsidiem decisões imediatas ou de curto prazo como para orientar a aplicação de outros diagnósticos demandados para decisões de médio e longo prazo. Planejamento urbano Área de preservação permanente (APP) Fundos de vale Gestão ambiental urbana Qualidade ambiental urbana Permanent preservation areas Urban valley bottom Urban environmental management Urban environmental quality ENGENHARIAS
4	Digital Soil Mapping of the Purdue Agronomy Center for Research and Education Shams R Rahmani (8300103) 07 May 2020 (has links) This research work concentrate on developing digital soil maps to support field based plant phenotyping research. We have developed soil organic matter content (OM), cation exchange capacity (CEC), natural soil drainage class, and tile drainage line maps using topographic indices and aerial imagery. Various prediction models (universal kriging, cubist, random forest, C5.0, artificial neural network, and multinomial logistic regression) were used to estimate the soil properties of interest. Agricultural Land Management Agricultural Land Planning Sustainable Agricultural Development Agronomy Digital soil mapping (DSM) Organic matter content Cation exchange capacity Natural soil drainage classes geostatistical methods Cubist modeling Random Forest models Universal Kriging C5.0 or see5 modeling Artificial neural network Tile drainage lines Soil spatial variation Plant Phenotyping Aerial Imagery digital elevation model (DEM) terrain attributes Soil and Landscape Very poorly drained poorly drained somewhat poorly drained moderately well drained User's accuracy producer's accuracy kappa coefficient Multinomial logit regression Tile Probe topographic wetness index Topographic Position Index slope height cross sectional curvature Relative slope position channel network distance SSURGO soils data internal validation external validation

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