Análisis comparativo de la estimación de la erosión hídrica con la metodología USLE y las técnicas RS SIG. Aplicación al entorno del tramo medio de la cuenca del río Jarama (Guadalajara)

La erosión hídrica en España es un problema grave, por las consecuencias que comporta en términos de pérdida del recurso suelo, sobre el que se sustenta la vida. Desde la década de los años ochenta del pasado siglo, la Administración Central ha realizado dos inventarios de erosión del suelo a nivel nacional: Los Mapas de Estados Erosivos (MEEs) y el Inventario Nacional de Erosión del Suelo (INES). En la presente Tesis Doctoral se han abordado las siguientes cuestiones: - Se ha profundizado en el análisis y aplicación de nuevas herramientas en la estimación del factor topográfico y del factor vegetación, que intervienen en los modelos de cálculo de las pérdidas de suelo, para mejorar la precisión en los resultados de la estimación de las tasas de erosión con los mismos. - Se ha establecido un procedimiento que permita realizar un inventario continuo de los Estados Erosivos de España, fijando como premisa el tiempo para su actualización. La Tesis desarrolla un procedimiento que permite comprobar que, la precisión utilizada en la cartografía base para determinar el factor vegetación y el factor topográfico del modelo USLE, influye en los resultados de la estimación de las tasas de erosión. También se ha realizado un estudio multi-temporal, analizado cuatro períodos: desde 1982 a 2014, con el fin de investigar las posibilidades de implementar un inventario continuo de los Estados Erosivos a nivel nacional; utilizando sensores remotos y técnicas de teledetección como herramienta para la actualización de los usos del suelo, factor determinante para estudiar la evolución de las tasas de erosión a lo largo del tiempo. Los resultados obtenidos de las investigaciones mencionadas, se han aplicado al tramo medio de la cuenca del río Jarama en la provincia de Guadalajara y han permitido comprobar que, la precisión de los datos utilizados en la aplicación del modelo USLE, influyen de una forma determinante en la estimación de las tasas de erosión y, además, hacen posible que la metodología, propuesta en esta Tesis, contribuya a establecer un inventario continuo de la evolución de los Estados Erosivos en un espacio multitemporal y a nivel de escenarios que abarcan una gran superficie. Gracias a este inventario se ha podido aportar información de la evolución de la cubierta vegetal y las pérdidas de suelo en la zona de estudio en el período analizado 1984-2015. ABSTRACT Water erosion in Spain is a serious problem and the consequences in terms of loss of soil resources on which life is based. Since the early eighties of last century, the central government has made two inventories of soil erosion nationwide: Maps of Erosive States (MEES) and the National Inventory of Soil Erosion (INES). In this Doctoral Thesis we have addressed the following issues: - It has deepened in the analysis and implementation of new tools in estimating the topographic factor and vegetation factor involved in the calculation models of soil loss, to improve accuracy in the results of the estimation of rates erosion therewith. - It has established a procedure allowing a continuous inventory of Erosion States of Spain, setting premised time for update. The thesis develops a method that allows to check that the precision used in the base map to determine the vegetation factor and topographical factor USLE model, influences the results of estimating erosion rates. There has also develop a multi-temporal study analyzed four periods: from 1982-2014, in order to investigate the possibilities of implementing a continuous inventory of erosion states at national level; using remote sensing techniques as a tool for updating land use, determining to study the evolution of erosion rates along the time factor. The results of the investigations referred to, have been applied to area around the middle reach of the Jarama river basin in the province of Guadalajara and would have shown that the accuracy of the data used in the model application USLE influence of decisive way estimating erosion rates and also make it possible that the methodology proposed in this thesis, help establish a continuous inventory of the evolution of erosive states in a multi-temporal space and level scenarios covering a large area. Thanks to this inventory was it able to provide information on the evolution of the vegetation cover and soil loss in the study area in the analyzed period 1984-2015.

Os impactos ambientais no meio físico: erosão e assoreamento na bacia hidrográfica do rio Taquari, MS, em decorrência da pecuária

O aumento da inundação em áreas do baixo curso do rio Taquari, no Pantanal do estado do Mato Grosso do Sul, tem transformado a pecuária desta região numa atividade com baixa rentabilidade, à medida que extensas áreas de campo passaram a ser inundadas vários meses durante o ano a partir da década de 70. A pecuária realizada em campos naturais de regiões úmidas do Pantanal indica que há necessidade de se investigar metodologias apropriadas para avaliação de impacto ambiental, que abordem impactos diretos, indiretos, cumulativos e processos do meio físico que alteram, de maneira prejudicial, o meio ambiente. Supõe-se que a inundação na planície do rio Taquari esteja relacionada com a ocupação antrópica nas áreas de planalto da bacia do rio Taquari. O presente trabalho tem por objetivo avaliar os impactos ambientais na planície de inundação do baixo curso do Taquari, decorrentes da ocupação antrópica da bacia hidrográfica do rio Taquari em sua totalidade, considerando os impactos ambientais causados pela pecuária à medida que se configura como principal atividade econômica da bacia bem como os processos erosivos e de assoreamento no quadro atual do regime de inundações. As etapas de caracterização da área, de análise dos impactos e as propostas de ações mitigadoras, previstas num Estudo de Impacto Ambiental, foram aqui analisadas. Foram utilizadas informações sobre as características do meio físico, biótico e socioeconômico, selecionadas a partir do levantamento dos dados existentes com recorte efetuado para a bacia hidrográfica do rio Taquari. Na maior parte dos temas, este foi um processo de levantamento, ordenamento e recuperação de informações, na escala original de 1:250.000, do Plano de Conservação da Bacia do Alto Paraguai-PCBAP, gerenciado no SPRING. Foram também realizadas viagens de campo para a complementação dos dados e para o levantamento de atividades antrópicas com verificações \"in loco\" da ocorrência de impacto ambiental. A maioria dos dados socioeconômicos compilados para o presente trabalho teve por base os censos agropecuários e demográficos realizados pelo IBGE. Os resultados obtidos demonstram que os impactos ambientais decorrentes da pecuária no planalto interferem no regime de inundação na planície da bacia, o que só foi possível de ser identificado a partir de análises integradas em toda a bacia hidrográfica do rio Taquari. Verificou-se que os métodos de EIA são adequados para identificar os impactos diretos decorrentes da pecuária, mas não são adequados para identificar os processos e seus efeitos cumulativos na extensão da bacia hidrográfica do rio Taquari. Além disto, a abordagem da avaliação ambiental estratégica, como procedimento para análise ambiental em políticas, planos e programas, mostra-se adequada para as análises na BHRT à medida que está centralizada nos efeitos do ambiente sobre as necessidades e oportunidades de desenvolvimento. Contudo, somente a recuperação de danos ambientais, o controle das origens dos impactos no ambiente e um sistema de gestão consciente de seus compromissos podem levar, juntamente com a melhora dos procedimentos técnicos e administrativos para análises ambientais, à uma maior proximidade da sustentabilidade ambiental na BHRT.

Nesting In The Clouds: Evaluating And Predicting Sea Turtle Nesting Beach Parameters From Lidar Data

Humans' desire for knowledge regarding animal species and their interactions with the natural world have spurred centuries of studies. The relatively new development of remote sensing systems using satellite or aircraft-borne sensors has opened up a wide field of research, which unfortunately largely remains dependent on coarse-scale image spatial resolution, particularly for habitat modeling. For habitat-specialized species, such data may not be sufficient to successfully capture the nuances of their preferred areas. Of particular concern are those species for which topographic feature attributes are a main limiting factor for habitat use. Coarse spatial resolution data can smooth over details that may be essential for habitat characterization. Three studies focusing on sea turtle nesting beaches were completed to serve as an example of how topography can be a main deciding factor for certain species. Light Detection and Ranging (LiDAR) data were used to illustrate that fine spatial scale data can provide information not readily captured by either field work or coarser spatial scale sources. The variables extracted from the LiDAR data could successfully model nesting density for loggerhead (Caretta caretta), green (Chelonia mydas), and leatherback (Dermochelys coriacea) sea turtle species using morphological beach characteristics, highlight beach changes over time and their correlations with nesting success, and provide comparisons for nesting density models across large geographic areas. Comparisons between the LiDAR dataset and other digital elevation models (DEMs) confirmed that fine spatial scale data sources provide more similar habitat information than those with coarser spatial scales. Although these studies focused solely on sea turtles, the underlying principles are applicable for many other wildlife species whose range and behavior may be influenced by topographic features.

A divulgação de provisões e passivos contingentes ambientais pelas empresas do setor de energia elétrica em comparação ao desenvolvimento da normatização da evidenciação contábil

O pressuposto desta pesquisa é de que a divulgação de informações ambientais, no âmbito das provisões e passivos contingentes, reagiu aos avanços na normatização contábil. A normatização contábil genérica sobre evidenciação de obrigações incertas era restrita, em meados de 1976, à Lei no 6.404, e assim permaneceu ao longo de pelo menos uma década e meia, quando começou a ser desenvolvida. Ao longo dos anos foram criados padrões obrigatórios de divulgação, com critérios de julgamento mais detalhados para a classificação da obrigação incerta em provável, possível ou remota. Embora ainda apresente algum grau de subjetividade, o desenvolvimento destes critérios pode ter contribuído para a diminuição da assimetria informacional: a empresa passou a contar com um conjunto de orientações mais claras e, portanto, com melhores condições de averiguar e divulgar suas obrigações incertas. Esse avanço contribuiu para que as obrigações ambientais passassem a ter maior exposição, principalmente no âmbito das empresas potencialmente poluidoras, como as do setor de energia elétrica, que utilizam recursos naturais e modificam o meio ambiente. Neste contexto, o objetivo deste estudo foi analisar as evidências de passivo ambiental divulgadas pelas empresas do setor de energia elétrica, de 1997 a 2014. Para tanto, foi desenvolvido um estudo qualitativo, descritivo e longitudinal, por meio da análise de conteúdo de 941 notas explicativas, de uma população de 64 empresas do setor de energia elétrica, de acordo com listagem na BM&FBovespa, em maio de 2015. A amostra foi constituída de 26 empresas, que divulgaram o total de 468 notas explicativas no site da CVM, de 1997 a 2014. Ao longo destes 18 anos, 14 empresas da amostra (53,85%) evidenciaram passivos ambientais ao menos uma vez e 12 instituições (46,15%) não o fizeram e, do total de 468 notas explicativas, 100 (21,37%) evidenciaram passivo ambiental. O número de evidências de passivos ambientais era pequeno em meados de 1997, mas ascendeu, com um aumento mais consistente a partir de 2006, ano que coincide com a aprovação da Norma e Procedimento de Contabilidade 22 - Provisões, Passivos, Contingências Passivas e Contingências Ativas, emitida pelo IBRACON. Adicionalmente, a materialidade quantitativa estava na média de 0,61% para provisões ambientais e 0,89% para os passivos contingentes ambientais, desconsiderando-se os outliers. A dimensão das notas explicativas, em termos de quantidade de palavras, foi crescente e diversificada. Em conclusão, a evidenciação contábil pode, em adição à evidenciação voluntária, ser um meio plausível para a divulgação de questões ambientais e redução da assimetria informacional, principalmente quando a normatização contábil se faz mais clara e detalhada.

An Investigation of Ozone Related Data and Development of a Model to Evaluate Ozone Episodes for Exceptional Event Criteria

The EPA promulgated the Exceptional Events Rule codifying guidance regarding exclusion of monitoring data from compliance decisions due to uncontrollable natural or exceptional events. This capstone examines documentation systems utilized by agencies requesting data be excluded from compliance decisions due to exceptional events. A screening tool is developed to determine whether an event would meet exceptional event criteria. New data sources are available to enhance analysis but evaluation shows many are unusable in their current form. The EPA and States must collaborate to develop consistent evaluation methodologies documenting exceptional events to improve the efficiency and effectiveness of the new rule. To utilize newer sophisticated data, consistent, user-friendly translation systems must be developed.

Advanced interpretation of subsidence in Murcia (SE Spain) using A-DInSAR data – modelling and validation

Subsidence is a natural hazard that affects wide areas in the world causing important economic costs annually. This phenomenon has occurred in the metropolitan area of Murcia City (SE Spain) as a result of groundwater overexploitation. In this work aquifer system subsidence is investigated using an advanced differential SAR interferometry remote sensing technique (A-DInSAR) called Stable Point Network (SPN). The SPN derived displacement results, mainly the velocity displacement maps and the time series of the displacement, reveal that in the period 2004–2008 the rate of subsidence in Murcia metropolitan area doubled with respect to the previous period from 1995 to 2005. The acceleration of the deformation phenomenon is explained by the drought period started in 2006. The comparison of the temporal evolution of the displacements measured with the extensometers and the SPN technique shows an average absolute error of 3.9±3.8 mm. Finally, results from a finite element model developed to simulate the recorded time history subsidence from known water table height changes compares well with the SPN displacement time series estimations. This result demonstrates the potential of A-DInSAR techniques to validate subsidence prediction models as an alternative to using instrumental ground based techniques for validation.

Radar interferometry techniques for the study of ground subsidence phenomena: a review of practical issues through cases in Spain

Subsidence related to multiple natural and human-induced processes affects an increasing number of areas worldwide. Although this phenomenon may involve surface deformation with 3D displacement components, negative vertical movement, either progressive or episodic, tends to dominate. Over the last decades, differential SAR interferometry (DInSAR) has become a very useful remote sensing tool for accurately measuring the spatial and temporal evolution of surface displacements over broad areas. This work discusses the main advantages and limitations of addressing active subsidence phenomena by means of DInSAR techniques from an end-user point of view. Special attention is paid to the spatial and temporal resolution, the precision of the measurements, and the usefulness of the data. The presented analysis is focused on DInSAR results exploitation of various ground subsidence phenomena (groundwater withdrawal, soil compaction, mining subsidence, evaporite dissolution subsidence, and volcanic deformation) with different displacement patterns in a selection of subsidence areas in Spain. Finally, a cost comparative study is performed for the different techniques applied.

A Simple RVoG Test for PolInSAR Data

In this paper, we present a simple algorithm for assessing the validity of the RVoG model for PolInSAR-based inversion techniques. This approach makes use of two important features characterizing a homogeneous random volume over a ground surface, i.e., the independence on polarization states of wave propagation through the volume and the structure of the polarimetric interferometric coherency matrix. These two features have led to two different methods proposed in the literature for retrieving the topographic phase within natural covers, i.e., the well-known line fitting procedure and the observation of the (1, 2) element of the polarimetric interferometric coherency matrix. We show that differences between outputs from both approaches can be interpreted in terms of the PolInSAR modeling based on the Freeman-Durden concept, and this leads to the definition of a RVoG/non-RVoG test. The algorithm is tested with both indoor and airborne data over agricultural and tropical forest areas.

Boston, Massachusetts Region LIDAR First Return Elevation Data, 2002

LIDAR (LIght Detection And Ranging) first return elevation data of the Boston, Massachusetts region from MassGIS at 1-meter resolution. This LIDAR data was captured in Spring 2002. LIDAR first return data (which shows the highest ground features, e.g. tree canopy, buildings etc.) can be used to produce a digital terrain model of the Earth's surface. This dataset consists of 74 First Return DEM tiles. The tiles are 4km by 4km areas corresponding with the MassGIS orthoimage index. This data set was collected using 3Di's Digital Airborne Topographic Imaging System II (DATIS II). The area of coverage corresponds to the following MassGIS orthophoto quads covering the Boston region (MassGIS orthophoto quad ID: 229890, 229894, 229898, 229902, 233886, 233890, 233894, 233898, 233902, 233906, 233910, 237890, 237894, 237898, 237902, 237906, 237910, 241890, 241894, 241898, 241902, 245898, 245902). The geographic extent of this dataset is the same as that of the MassGIS dataset: Boston, Massachusetts Region 1:5,000 Color Ortho Imagery (1/2-meter Resolution), 2001 and was used to produce the MassGIS dataset: Boston, Massachusetts, 2-Dimensional Building Footprints with Roof Height Data (from LIDAR data), 2002 [see cross references].

New Hampshire, 1796 Raster Image

This layer is a digitized geo-referenced raster image of a 1796 map of New Hampshire drawn by D.F. Sotzmann. These Sotzmann maps (10 maps of New England and Mid-Atlantic states) typically portray both natural and manmade features. They are highly detailed with symbols for churches, roads, court houses, distilleries, iron works, mills, academies, county lines, town lines, and more. Relief is usually indicated by hachures and country boundaries have also been drawn. Place names are shown in both German and English and each map usually includes an index to land grants. Prime meridians used for this series are Greenwich and Washington, D.C.

Vermont, 1796 Raster Image

This layer is a digitized geo-referenced raster image of a 1796 map of Vermont drawn by D.F. Sotzmann. These Sotzmann maps (10 maps of New England and Mid-Atlantic states) typically portray both natural and manmade features. They are highly detailed with symbols for churches, roads, court houses, distilleries, iron works, mills, academies, county lines, town lines, and more. Relief is usually indicated by hachures and country boundaries have also been drawn. Place names are shown in both German and English and each map usually includes an index to land grants. Prime meridians used for this series are Greenwich and Washington, D.C.

Massachusetts, 1797 Raster Image

This layer is a digitized geo-referenced raster image of a 1797 map of Massachusetts drawn by D.F. Sotzmann. These Sotzmann maps (10 maps of New England and Mid-Atlantic states) typically portray both natural and manmade features. They are highly detailed with symbols for churches, roads, court houses, distilleries, iron works, mills, academies, county lines, town lines, and more. Relief is usually indicated by hachures and country boundaries have also been drawn. Place names are shown in both German and English and each map usually includes an index to land grants. Prime meridians used for this series are Greenwich and Washington, D.C.

Rhode Island, 1797 Raster Image

This layer is a digitized geo-referenced raster image of a 1797 map of Rhode Island drawn by D.F. Sotzmann. These Sotzmann maps (10 maps of New England and Mid-Atlantic states) typically portray both natural and manmade features. They are highly detailed with symbols for churches, roads, court houses, distilleries, iron works, mills, academies, county lines, town lines, and more. Relief is usually indicated by hachures and country boundaries have also been drawn. Place names are shown in both German and English and each map usually includes an index to land grants. Prime meridians used for this series are Greenwich and Washington, D.C.

Connecticut, 1796 Raster Image

This layer is a digitized geo-referenced raster image of a 1796 map of Connecticut drawn by D.F. Sotzmann. These Sotzmann maps (10 maps of New England and Mid-Atlantic states) typically portray both natural and manmade features. They are highly detailed with symbols for churches, roads, court houses, distilleries, iron works, mills, academies, county lines, town lines, and more. Relief is usually indicated by hachures and country boundaries have also been drawn. Place names are shown in both German and English and each map usually includes an index to land grants. Prime meridians used for this series are Greenwich and Washington, D.C.