Detecting the effects of hydrocarbon pollution in the Amazon forest using hyperspectral satellite images

The global demand for fossil energy is triggering oil exploration and production projects in remote areas of the world. During the last few decades hydrocarbon production has caused pollution in the Amazon forest inflicting considerable environmental impact. Until now it is not clear how hydrocarbon pollution affects the health of the tropical forest flora. During a field campaign in polluted and pristine forest, more than 1100 leaf samples were collected and analysed for biophysical and biochemical parameters. The results revealed that tropical forests exposed to hydrocarbon pollution show reduced levels of chlorophyll content, higher levels of foliar water content and leaf structural changes. In order to map this impact over wider geographical areas, vegetation indices were applied to hyperspectral Hyperion satellite imagery. Three vegetation indices (SR, NDVI and NDVI705) were found to be the most appropriate indices to detect the effects of petroleum pollution in the Amazon forest

Spectral and growth characteristics of willows and maize in soil contaminated with a layer of crude or refined oil

Remote sensing holds great potential for detecting stress in vegetation caused by hydro-carbons, but we need to better understand the effects of hydrocarbons on plant growth and specific spectral expression. Willow (Salix viminalis var. Tora) cuttings and maize (Zea mays var. Lapriora) seedlings were grown in pots of loam soil containing a hydrocarbon-contaminated layer at the base of the pot (crude or refined oil) at concentrations of 0.5, 5, or 50 g·kg−1 . Chlorophyll concen-tration, biomass, and growth of plants were determined through destructive and nondestructive sampling, whilst reflectance measurements were made using portable hyperspectral spectrometers. All biophysical (chlorophyll concentration and growth) variables decreased in the presence of high concentrations of hydrocarbons, but at lower concentrations an increase in growth and chlorophyll were often observed with respect to nonpolluted plants, suggesting a biphasic response to hydrocarbon presence. Absorption features were identified that related strongly to pigment concentration and biomass. Variations in absorption feature characteristics (band depth, band area, and band width) were dependent upon the hydrocarbon concentration and type, and showed the same biphasic pattern noted in the biophysical measurements. This study demonstrates that the response of plants to hydrocarbon pollution varies according to hydrocarbon concentration and that remote sensing has the potential to both detect and monitor the variable impacts of pollution in the landscape.Atmospheric Remote Sensin

Caracterização e estudo comparativo de exsudações de hidrocarbonetos e plays petrolíferos em bacias terrestres das regiões central do Irã e sudeste do Brasil usando sensoriamento remoto espectral

Orientador: Carlos Roberto de Souza FilhoTese (doutorado) - Universidade Estadual de Campinas, Instituto de GeociênciasResumo: O objetivo desta pesquisa foi explorar as assinaturas de exsudações de hidrocarbonetos na superfície usando a tecnologia de detecção remota espectral. Isso foi alcançado primeiro, realizando uma revisão abrangente das capacidades e potenciais técnicas de detecção direta e indireta. Em seguida, a técnica foi aplicada para investigar dois locais de teste localizados no Irã e no Brasil, conhecidos por hospedar sistemas ativos de micro-exsudações e afloramentos betuminosos, respectivamente. A primeira área de estudo está localizada perto da cidade de Qom (Irã), e está inserida no campo petrolífero Alborz, enterrado sob sedimentos datados do Oligoceno da Formação Upper Red. O segundo local está localizado perto da cidade de Anhembi (SP), na margem oriental da bacia do Paraná, no Brasil, e inclui acumulações de betume em arenitos triássicos da Formação Pirambóia. O trabalho na área de Qom integrou evidências de (i) estudos petrográficos e geoquímicos em laboratório, (ii) investigações de afloramentos em campo, e (iii) mapeamento de anomalia em larga escala através de conjuntos de dados multi-espectrais ASTER e Sentinel-2. O resultado deste estudo se trata de novos indicadores mineralógicos e geoquímicos para a exploração de micro-exsudações e um modelo de micro-exsudações atualizado. Durante este trabalho, conseguimos desenvolver novas metodologias para análise de dados espectroscópicos. Através da utilização de dados simulados, indicamos que o instrumento de satélite WorldView-3 tem potencial para detecção direta de hidrocarbonetos. Na sequência do estudo, dados reais sobre afloramentos de arenitos e óleo na área de Anhembi foram investigados. A área foi fotografada novamente no chão e usando o sistema de imagem hiperespectral AisaFENIX. Seguiu-se estudos e amostragem no campo,incluindo espectroscopia de alcance fechado das amostras no laboratório usando instrumentos de imagem (ou seja, sisuCHEMA) e não-imagem (ou seja, FieldSpec-4). O estudo demonstrou que uma abordagem espectroscópica multi-escala poderia fornecer uma imagem completa das variações no conteúdo e composição do betume e minerais de alteração que acompanham. A assinatura de hidrocarbonetos, especialmente a centrada em 2300 nm, mostrou-se consistente e comparável entre as escalas e capaz de estimar o teor de betume de areias de petróleo em todas as escalas de imagemAbstract: The objective of this research was to explore for the signatures of seeping hydrocarbons on the surface using spectral remote sensing technology. It was achieved firstly by conducting a comprehensive review of the capacities and potentials of the technique for direct and indirect seepage detection. Next, the technique was applied to investigate two distinctive test sites located in Iran and Brazil known to retain active microseepage systems and bituminous outcrops, respectively. The first study area is located near the city of Qom in Iran, and consists of Alborz oilfield buried under Oligocene sediments of the Upper-Red Formation. The second site is located near the town of Anhembi on the eastern edge of the Paraná Basin in Brazil and includes bitumen accumulations in the Triassic sandstones of the Pirambóia Formation. Our work in Qom area integrated evidence from (i) petrographic, spectroscopic, and geochemical studies in the laboratory, (ii) outcrop investigations in the field, and (iii) broad-scale anomaly mapping via orbital remote sensing data. The outcomes of this study was novel mineralogical and geochemical indicators for microseepage characterization and a classification scheme for the microseepage-induced alterations. Our study indicated that active microseepage systems occur in large parts of the lithofacies in Qom area, implying that the extent of the petroleum reservoir is much larger than previously thought. During this work, we also developed new methodologies for spectroscopic data analysis and processing. On the other side, by using simulated data, we indicated that WorldView-3 satellite instrument has the potential for direct hydrocarbon detection. Following this demonstration, real datasets were acquired over oil-sand outcrops of the Anhembi area. The area was further imaged on the ground and from the air by using an AisaFENIX hyperspectral imaging system. This was followed by outcrop studies and sampling in the field and close-range spectroscopy in the laboratory using both imaging (i.e. sisuCHEMA) and nonimaging instruments. The study demonstrated that a multi-scale spectroscopic approach could provide a complete picture of the variations in the content and composition of bitumen and associated alteration mineralogy. The oil signature, especially the one centered at 2300 nm, was shown to be consistent and comparable among scales, and capable of estimating the bitumen content of oil-sands at all imaging scalesDoutoradoGeologia e Recursos NaturaisDoutor em Geociências2015/06663-7FAPES

Development of an unsupervised remote sensing methodology of detect surface leakage from terrestrial CO2 storage sites

Imperial Users onl

Detection of simulated leaks from geologically stored CO2 With 13C monitoring

Precise methods for the detection of geologically stored CO2within and above soil surfaces are an impor-tant component of the development of carbon capture and storage (CCS) under terrestrial environments.Although CO2leaks are not expected in well-chosen and operated storage sites, monitoring is required bylegislation and any leakage needs to be quantified under the EU Emissions Trading Directive. The objec-tive of the present research was to test if13C stable isotope motoring of soil and canopy atmosphere CO2increases our detection sensitivity for CCS-CO2as compared with concentration monitoring only. A CO2injection experiment was designed to create a horizontal CO2gradient across 6 m × 3 m plots, which weresown with oats in 2011 and 2012. Injected CO2was methane derived and had an isotopic signature of−46.2‰. The CO2concentrations were measured within the soil profile with passive samplers and at sev-eral heights within the crop canopies. The CO2fluxes and their13C signatures were also measured acrossthe experimental plots. In situ monitoring and gas samples measurements were conducted with a cavityring down spectrometer (CRDS). The plots displayed hot spots of injected-CO2leakage clearly detectableby either concentration or isotopic signature measurements. In addition, the13C signature measurementsallow us to detect injected CO2in plot regions where its presence could not be unequivocally ascertainedbased on concentration measurement alone.acceptedVersio

Indirect detection of soil contamination by liquid hydrocarbons from spectral changes in crops

Orientador: Carlos Roberto de Souza FilhoTese (doutorado) - Universidade Estadual de Campinas, Instituto de GeociênciasResumo: A contaminação do solo por hidrocarbonetos líquidos (HCs) é um problema que atinge o mundo todo e pode causar sérios danos ao meio ambiente e à saúde humana. A identificação antecipada de pequenos vazamentos em dutos de derivados de petróleo contribui para a rápida contenção e solução do problema. Métodos indiretos de detecção envolvem a descrição de anomalias na vegetação atingida pelos contaminantes. A proposta dessa tese foi avaliar as alterações na camada de vegetação desenvolvida em solo contaminado com diesel e gasolina, utilizando técnicas de espectroscopia de refletância e de imageamento. Parte-se da hipótese de que as plantas em solo com HCs germinam e se desenvolvem com modificações morfológicas e fisiológicas, as quais podem ser potencialmente detectadas pelas alterações no espectro da folha e do dossel. Os principais objetivos da pesquisa foram: (i) analisar as diferenças entre as plantas contaminadas e sadias com técnicas de espectroscopia de refletância (remoção do contínuo, red edge, índices espectrais e feições de absorção), no intervalo espectral entre o visível e o infravermelho de ondas curtas (350 ¿ 2500 nm); (ii) avaliar a técnica dos mapas autoorganizáveis (SOM) para diferenciar plantas contaminadas e plantas sadias; e (iii) avaliar se as diferenças observadas no espectro do dossel contaminado podem ser detectadas por sensores remotos (WorldView-3 e câmera multiespectral MicaSense RedEdge), simulados a partir da reamostragem de bandas ultraespectrais (espectrorradiômetro de campo ASD-FieldSpec) e hiperespectrais (aerosensor ProSpecTIR). A investigação envolveu duas escalas de trabalho. Primeiramente, um experimento de vazamento de pequeno porte foi instalado em casa de vegetação, com coleta de espectros foliares de braquiária e soja perene. O segundo experimento foi concebido para simular um vazamento em escala real, durante o qual foram coletados dados foliares e de dossel de braquiária, soja perene e milho. Os resultados mostraram diferenças sutis entre as plantas contaminadas e sadias em nível foliar. Ao nível de dossel, as diferenças foram mais significativas. A contaminação afetou a estrutura do dossel, revelando maior influência do solo exposto nessas áreas em relação às áreas sem contaminação. A análise multivariada dos parâmetros espectrais (com técnica dos mapas auto-organizáveis e análise de agrupamento) melhorou a detecção de anomalias nas plantas contaminadas em relação à análise dos parâmetros isolados. Índices espectrais foram também utilizados para avaliar a capacidade dos sensores remotos na detecção de anomalias na vegetação contaminada. Os resultados mostraram que os produtos desses sensores podem distinguir o estresse da vegetação ao nível de dossel, quando a contaminação ocorre antes do plantioAbstract: The contamination of soil by liquid hydrocarbons (HCs) is a worldwide problem and can cause serious damage to the environment and human health. Early identification of small leaks in hydrocarbon pipelines contribute to the rapid suppression and solution of the leakage. Indirect detection methods involve the detection of anomalies in vegetation affected by contaminants. The aim of this thesis is to evaluate changes in the vegetation cover developed in soil contaminated with diesel and gasoline, using reflectance and imaging spectroscopic techniques. The assumption is that plants grown in soil with HCs germinate and develop with morphological and physiological changes, which can potentially be detected by changes in the spectrum of leaf and canopy. Specific objectives of the research are: (i) to analyze the differences between contaminated and healthy plants with reflectance spectroscopy techniques (continuum removal, red edge, spectral indices and absorption features) in the spectral range between the visible and infrared shortwave (350 - 2500 nm); (ii) to evaluate the technique of self-organizing maps (SOM) to differentiate contaminated plants and healthy plants; and (iii) to assess whether the differences observed in the spectra of contaminated canopy can be detected by remote sensors (WorldView-3 superspectral and MicaSense RedEdge multispectral sensors), simulated from resampled ultraspectral (ASD-FieldSpec field spectrometer) and hyperspectral bands (ProSpecTIR airborne sensor). The research involved two scales of work. Firstly, a small leak experiment was conducted in a greenhouse, with the collection of leaf spectra of brachiaria and perennial soybean. The second experiment was designed to simulate a leak in real scale; data were collected of leaf and canopy of brachiaria, perennial soybean and maize. Overall, the results at leaf level showed subtle differences between contaminated and healthy plants. The main differences were observed at the canopy level. The contamination affected the canopy structure, showing greater influence of exposed soil in these sites compared to areas without contamination. Multivariate analysis of spectral parameters (using self-organizing maps technique and cluster analysis) improved the detection of anomalies in contaminated plants rather than analysis of isolated parameters. Spectral indices were also used to evaluate the capacity of remote sensors in detecting spectral anomalies on contaminated vegetation. The results showed that the products of these sensors can distinguish stressed vegetation at the canopy level when contamination occurs before plantingDoutoradoGeologia e Recursos NaturaisDoutora em Ciências141100/2012-5CNP

Hyperspectral and Thermal Remote Sensing of Plant Stress Reponses to Oil Pollution.

This study investigates the potential use of hyperspectral and thermal remote sensing for the early pre-visual detection and quantification of plant stress caused by oil pollution. Further, it examines the potential for these techniques to discriminate between oil pollution and two typically encountered plant stresses of waterlogging and water deficit. Results show that oil pollution, waterlogging and water deficit significantly decreased the physiological functions of plants and can result in pre-visual changes in spectral and thermal responses. Various spectral indices such as (R755-R716)/(R755+R716) and R800/R6O6 were efficient for the early detection of oil-induced stress in maize (up to 10 days earlier) and bean (up to 4 days earlier), respectively. These indices and other simple ratios of reflectance such as R673/R545 were also sensitive in the early detection (up to 6 days earlier) of stress symptoms caused by waterlogging in bean. The canopy absolute temperature and thermal index (IG) were good indicators of oil related stress in bean, but were insensitive to waterlogging. Absolute leaf temperature had minimal potential for detecting oil pollution in maize. While the spectral indices lacked ability for the early detection of stress caused by water deficit at the leaf scale in both maize and bean, absolute temperature was effective in this regard irrespective of scale of measurement. Results show that by combining spectral and thermal information, oil pollution can be discriminated from waterlogging or water deficit treatment. This study concludes that hyperspectral and thermal remote sensing have the potential to detect and quantify plant stress caused by oil pollution and it is possible to discriminate between this and other common stresses. However, further work is needed to refine and operationalise the approach, and the problems and challenges associated with this are presented and discussed

Habitats and Biota of the Gulf of Mexico: Before the Deepwater Horizon Oil Spill: Volume 1: Water Quality, Sediments, Sediment Contaminants, Oil and Gas Seeps, Coastal Habitats, Offshore Plankton and Benthos, and Shellfish

environmental management; marine; freshwater science