Academic literature on the topic 'Vegetation indece'

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Journal articles on the topic "Vegetation indece"

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Veltrop, Marcel H. A. M., Maurice J. L. M. F. Bancsi, Rogier M. Bertina, and Jan Thompson. "Role of Monocytes in Experimental Staphylococcus aureus Endocarditis." Infection and Immunity 68, no. 8 (August 1, 2000): 4818–21. http://dx.doi.org/10.1128/iai.68.8.4818-4821.2000.

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ABSTRACT In the pathogenesis of bacterial endocarditis (BE), the clotting system plays a cardinal role in the formation and maintenance of the endocardial vegetations. The extrinsic pathway is involved in the activation of the coagulation pathway with tissue factor (TF) as the key protein. Staphylococcus aureus is a frequently isolated bacterium from patients with BE. We therefore investigated whetherS. aureus can induce TF activity (TFA) on fibrin-adherent monocytes, used as an in vitro model of BE. We also assessed in vivo in rabbits with catheter induced vegetations, the effect of S. aureus infection on vegetational TFA. In vitro experiments showed that adherent S. aureus induced TFA on fibrin-adherent monocytes which was optimal at a bacterium/monocyte ratio of 1 to 1. Monocyte damage occurred when this ratio exceeded 4 to 1 (visually) or 6 to 1 (propidium iodide influx) Consequently, TFA decreased. In vivoS. aureus led to very high bacterial numbers in the vegetations and a significant increase of their weight. However, TFA of infected vegetations was the same as of sterile ones. This may be due to the high bacteria to monocyte ratio as well as bacterium-induced monocyte damage. Teicoplanin treatment of infected rabbits reduced bacterial numbers in the blood and in the vegetations. Two-day treatment resulted in an increase of vegetational TFA, but after four-day treatment vegetational TFA dropped, most probably due to a suboptimal bacterium/monocyte ratio. S. aureus endocarditis in etoposide (Vepesid)-treated rabbits, leading to a selective monocytopenia, caused a rapid death of the animals. In these rabbits no vegetations were found at all. We conclude that, likeStreptococcus sanguis and Staphylococcus epidermidis, S. aureus is able to induce TFA in fibrin-adherent blood monocytes. In addition, monocytes have a protective effect during the course of S. aureusendocarditis.
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Xu Mingzhu, 许明珠, 徐浩 Xu Hao, 孔鹏 Kong Peng, and 吴艳兰 Wu Yanlan. "结合植被指数和卷积神经网络的遥感植被分类方法." Laser & Optoelectronics Progress 59, no. 24 (2022): 2428005. http://dx.doi.org/10.3788/lop202259.2428005.

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Dhakal, Richa, and Ram Asheshwar Mandal. "APPLICATION OF VEGETATION INDEXES TO ASSESS CARBON STOCK." Mercator 21, no. 1 (June 15, 2022): 1–14. http://dx.doi.org/10.4215/rm2022.e21018.

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This was objectively conducted to estimate the carbon stock, to show the relation between carbon stock and indices and to assess the factors affecting carbon stock in community forests. Three community forests (CFs) namely Gumalchowki, Mahakalsthan and Mahalaxmi of Chandragiri Municipality in Nepal were selected as research sites. Altogether 135 plots were randomly established to collect data from the field. The biomass was calculated using Chave et al., equation which was converted into carbon stock multiplying by default value 0.47. The values of Normalized Difference Vegetation Index (NDVI), Difference Vegetation Index (DVI) and Infrared Percentage Vegetation Index (IPVI) were calculated and regression equation between the indices and carbon stock was performed. The result showed that total above ground carbon stock was highest in Mahalaxmi CF with 30.42 ton/ha, followed by Mahakalsthan CF with 22.62 ton/ha and comparatively lowest with 21.55 ton/ha in Gumalchowki CF. The regression analysis between carbon stock and indices showed significantly and positive correlation. The R2 value of NDVI of Gumalchowki, Mahakalsthan and Mahalaxmi CF were found to be 0.51, 0.54 and 0.58, also, RMSE value of CFs were 1.41, 1.36 and 1.91 respectively. Principal component analysis showed that road construction, transmission line expansion, soil erosion, encroachment, disease, weeds, recreation, illegal logging are the major factors affecting carbon stock in all three community forests. Keywords: Carbon, Nepal, Community Forests.
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Liang, Juan, Chen Liu, Gui-Quan Sun, Li Li, Lai Zhang, Meiting Hou, Hao Wang, and Zhen Wang. "Nonlocal interactions between vegetation induce spatial patterning." Applied Mathematics and Computation 428 (September 2022): 127061. http://dx.doi.org/10.1016/j.amc.2022.127061.

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Yoon, Jung-Beom, Young-Nam Yoon, and Yoon-Ha Kim. "Utilization of Vegetation Indice in Agricultural Field." Journal of Agriculture & Life Science 55, no. 5 (October 30, 2021): 1–9. http://dx.doi.org/10.14397/jals.2021.55.5.1.

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Augustin, Pascal, Ghada Alsalih, Yoann Launey, Sandrine Delbosc, Liliane Louedec, Véronique Ollivier, Françoise Chau, et al. "Predominant Role of Host Proteases in Myocardial Damage Associated with Infectious Endocarditis Induced by Enterococcus faecalis in a Rat Model." Infection and Immunity 81, no. 5 (March 11, 2013): 1721–29. http://dx.doi.org/10.1128/iai.00775-12.

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ABSTRACTInfective endocarditis (IE) remains a life-threatening infectious disease with high morbidity and mortality. The objectives of the present study are to assess the host proteolytic activities of the vegetations and their cytotoxic potential in a rat model of experimental IE. Rats were infected with a strain ofEnterococcus faecalisof particularly low virulence and weak protease expression. We tested the presence of proteases released by infiltrated leukocytes (matrix metalloproteinases and elastase) or producedin situwithin the septic vegetation, such as those linked to the fibrinolytic system (plasmin and plasminogen activators). We also assessed the tissue damage induced by the infective thrombusin vitroandex vivo. The model of IE was characterized by larger and more extensive vegetations in infected than in nonseptic rats and by an intense neutrophil infiltrate interfacing with the injured underlying tissue. Neutrophil extracellular DNA was shown to trap bacteria and to produce increased levels of cell-free DNA in plasma. Matrix metalloproteinase-9, elastase, and plasminogen activators were increased in septic versus nonseptic vegetations (as shown by zymography and immunohistology). Finally, proteolysis of the extracellular matrix and apoptosis were shown to be associated with host proteases. Bacteria exhibited no detectable proteolytic activity or direct cytotoxic effects. Bacterial membranes/dead bacteria were sufficient to induce leukocyte recruitment and activation that could promote vegetation formation and growth. Our results suggest that, despite the lack of bacterial proteases, the continuous attractant signals coming from bacterial colonies may lead to a chronic and deleterious aggression toward myocardial/valvular tissues by host proteases.
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Reyes-González, Arturo, David G. Reta-Sánchez, Juan I. Sánchez-Duarte, Víctor M. Rodríguez-Moreno, Enrique Hernández-Leal, and Iván Franco-Gaytán. "Desarrollo del coeficiente de cultivo para cártamo forrajero basado en índices de vegetación." Tecnología y ciencias del agua 11, no. 6 (November 1, 2020): 39–80. http://dx.doi.org/10.24850/j-tyca-2020-06-02.

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El coeficiente de cultivo (Kc) es esencial para la programación del riego en la agricultura. Los objetivos de este estudio fueron monitorear la altura e índice de vegetación NDVI (índice de vegetación de diferencia normalizada, NDVI por sus siglas en inglés) del cártamo durante dos ciclos de cultivo, desarrollar un nuevo Kc con base en el NDVI y calcular la evapotranspiración de cultivo (ETc), tomando en cuenta los valores de Kc. El estudio se realizó en los ciclos otoño-invierno 2016-2017 y 2017-2018 en Matamoros, Coahuila, México. Se evaluaron los cultivares Guayalejo, Selkino y CD-868. La siembra se realizó en un suelo seco el 10 y 12 de diciembre de 2016 y 2017, respectivamente. En el ciclo 2016-2017 se aplicaron tres riegos de auxilio y en el ciclo 2017-2018 dos. El NDVIcampo se obtuvo con el equipo GreenSeeker y el NDVIsatelital de imágenes Landsat 7 y 8. Se estableció una relación entre el NDVIcampo y el Kc tomado del manual 56 de la FAO. Los resultados indicaron curvas similares de NDVIcampo en ambos ciclos. Altos coeficientes de determinación (r2 = 0.93 y 0.89) se obtuvieron entre el NDVIcampo y el Kc de FAO-56. Se generó una ecuación lineal (Kc = 1.064 * NDVI + 0.212) para ambos ciclos. Los nuevos valores de Kc se multiplicaron por la evapotranspiración de referencia (ETo) para calcular ETc. Con esta ecuación se propone un modelo de cálculo para derivar recomendaciones de lámina de riego acordes con la etapa fenológica del cártamo.
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Swami, Abhishek. "Impact of Automobile Induced Air Pollution on roadside vegetation: A Review." ESSENCE International Journal for Environmental Rehabilitation and Conservation 9, no. 1 (August 15, 2018): 101–16. http://dx.doi.org/10.31786/09756272.18.9.1.113.

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Aleixo, Natacha Cíntia Regina, and João Cândido André Silva Neto. "Índice de vegetação e comportamento da temperatura do ar em Tefé/Amazonas/Brasil." Revista Brasileira de Geografia Física 11, no. 2 (2018): 864–76. http://dx.doi.org/10.26848/rbgf.v10.6.p864-876.

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Aleixo, Natacha Cíntia Regina, and João Cândido André Silva Neto. "Índice de vegetação e comportamento da temperatura do ar em Tefé/Amazonas/Brasil." Revista Brasileira de Geografia Física 11, no. 3 (2018): 864–76. http://dx.doi.org/10.26848/rbgf.v11.3.p864-876.

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Dissertations / Theses on the topic "Vegetation indece"

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Roderick, Michael L. "Satellite derived vegetation indices for monitoring seasonal vegetation conditions in Western Australia." Thesis, Curtin University, 1994. http://hdl.handle.net/20.500.11937/518.

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The monitoring of continental and global scale net primary production remains a major focus of satellite-based remote sensing. Potential benefits which follow are diverse and include contributions to, and improved scientific understanding of, ecological systems, rangeland management, famine warning, agricultural commodity trading, and the study of global climate change.A NOAA-AVHRR data set containing monthly observations of green vegetation cover over a ten year period was acquired and analysed, to extract information on seasonal conditions. The data were supplied as a vegetation index, commonly known as the Normalised Difference Vegetation Index (NDVI), with a spatial resolution of approximately five km. The data set was acquired from three different satellites, and calibration problems were known to exist. A new technique was developed to estimate, and subsequently remove, the calibration bias present in the data.Monthly rainfall measurements were used as surrogate ground truth to validate the NDVI data. For regions of native vegetation, linear models relating NDVI to previous rainfall were derived, using transfer function techniques in common use in systems engineering. The models demonstrate that, in mid-latitude regions, the NDVI is a linear function of rainfall recorded over the preceding seven or eight months.Annual summaries of the image data were developed to highlight the amount and timing of plant growth. Three fundamental questions were posed as an aid to the development of the summary technique: where, when and how much? These summaries highlight the extraordinary spatial and temporal variations in plant growth, and hence rainfall, over much of Western Australia each year.Standard analysis techniques used in time series analysis, such as classical decomposition, were successfully applied to the analysis of NDVI time series. These techniques highlighted structural differences in the image data, due to land use, climatic factors and vegetation type.Overall, the results of the research undertaken in this study, using NOAA-AVHRR data in Western Australia, demonstrate that vegetation indices acquired from satellite platforms can be used to monitor continental scale seasonal conditions in an effective manner. As a consequence of these results, further research using this type of data is proposed in rangeland management and climate change modelling.
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Magalhães, Leonardo Pinto de. "Análise de imagens no desenvolvimento e status de fósforo do minitomateiro grape cultivado em sistema semi-hidropônico." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-13032019-152808/.

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A análise de imagens é uma das formas de avaliar o desenvolvimento das plantas, tanto para correlacionar aspectos biofísicos dos mesmos, como para a detecção de doenças. Através das imagens podem ser calculados índices vegetativos que se correlacionem com os teores de nutrientes nas folhas. Com essa perspectiva, o presente trabalho objetivou avaliar quais indices vegetativos melhor se correlacionariam com a taxa de fósforo nas folhas de tomateiros. Foi realizado o cultivo de uma cultivar de minitomate, com cinco doses de fósforo (0, 25, 50, 75 e 100%) do P recomendado (na formulação da solução nutritiva). Em diferentes etapas do desenvolvimento da planta foram coletadas amostras das folhas para obtenção das imagens, através de escâner e máquina fotográfica, e diagnose foliar. Foram determinadas as biorrespostas das plantas ao longo do tempo. Uma rede neural artificial foi desenvolvida para estimar os teores de fósforo foliares no minitomate grape. A análise do desenvolvimento da planta permitiu concluir que a dose 100% de P2O5 utilizada no experimento foi suficiente para suprir a demanda nutricional do minitomateiro. Aos 64 dias após o transplantio (DAT) foi observada a maior queda nos teores de fósforo nas folhas, coincidindo com o amadurecimento dos frutos. Propõe-se, para a cultivar estudada, que a dignose foliar seja feita aos 50 DAT. Os índices vegetativos obtidos pela análise de imagem e selecionados pela análise de componentes principais (ICVE e Bn, tanto da parte abaxial quanto adaxial) podem ser utilizados para estimar a diagnose foliar de P na cultivar de minitomate grape. A avaliação dos índices vegetativos indicou que a obtenção de imagens com o escâner é mais adequado do que com a câmera fotográfica. Para a cultivar estudada, verificou-se que na dosagem de 100% de P2O5 teor de P nas folhas fica abaixo de 4,0 g kg-1. Em relação à rede neural desenvolvida, ao categorizar os valores de P de acordo com a literatura, a mesma obteve uma taxa de acerto de 90%.
The analysis of images is one of the ways to evaluate the development of plants, both to correlate biophysical aspects of the same, as for the detection of diseases. Through the images can be calculated vegetative indexes that correlate with the contents of nutrients in the leaves. With this perspective, the present studied aimed to evaluate which vegetative indexes would best correlate with the phosphorus rate in tomato leaves. A minitomato grape cultivar with five phosphorus doses (0, 25, 50, 75 and 100%) of the recommended P (in the formulation of the nutrient solution) was carried out. At different stages of plant development, leaf samples were collected to obtain the images, with scanner and camera, and foliar diagnosis. The bio-responses of plants were determined over time. An artificial neural network was developed to estimate leaf phosphorus levels in the grape minitomate. The analysis of the development of the plant allowed to conclude that the dose 100% of P2O5 used in the experiment was enough to supply the nutritional demand of the minitomateiro. At 64 days after transplanting (DAT), the highest drop in phosphorus content in the leaves was observed, coinciding with the ripening of the fruits. It is proposed, for the studied cultivar, that the leaf dignity should be made at 50 DAT. The vegetative indexes obtained by the image analysis and selected by the principal components analysis (ICVE and Bn, both abaxial and adaxial) can be used to estimate the leaf diagnosis of P in the minitomate grape cultivar. The evaluation of vegetative indexes indicated that obtaining images with the scanner is more appropriate than with the photographic camera. For the cultivar studied, it was verified that in the dosage of 100% of P2O5 content of P in the leaves is below 4.0 g kg-1. In relation to the developed neural network, when categorizing the P values according to the literature, it obtained a 90% correctness rate.
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Roderick, Michael L. "Satellite derived vegetation indices for monitoring seasonal vegetation conditions in Western Australia." Curtin University of Technology, School of Surveying and Land Information, 1994. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=14815.

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The monitoring of continental and global scale net primary production remains a major focus of satellite-based remote sensing. Potential benefits which follow are diverse and include contributions to, and improved scientific understanding of, ecological systems, rangeland management, famine warning, agricultural commodity trading, and the study of global climate change.A NOAA-AVHRR data set containing monthly observations of green vegetation cover over a ten year period was acquired and analysed, to extract information on seasonal conditions. The data were supplied as a vegetation index, commonly known as the Normalised Difference Vegetation Index (NDVI), with a spatial resolution of approximately five km. The data set was acquired from three different satellites, and calibration problems were known to exist. A new technique was developed to estimate, and subsequently remove, the calibration bias present in the data.Monthly rainfall measurements were used as surrogate ground truth to validate the NDVI data. For regions of native vegetation, linear models relating NDVI to previous rainfall were derived, using transfer function techniques in common use in systems engineering. The models demonstrate that, in mid-latitude regions, the NDVI is a linear function of rainfall recorded over the preceding seven or eight months.Annual summaries of the image data were developed to highlight the amount and timing of plant growth. Three fundamental questions were posed as an aid to the development of the summary technique: where, when and how much? These summaries highlight the extraordinary spatial and temporal variations in plant growth, and hence rainfall, over much of Western Australia each year.Standard analysis techniques used in time series analysis, such as classical decomposition, were successfully applied to the analysis of NDVI time series. These techniques highlighted ++
structural differences in the image data, due to land use, climatic factors and vegetation type.Overall, the results of the research undertaken in this study, using NOAA-AVHRR data in Western Australia, demonstrate that vegetation indices acquired from satellite platforms can be used to monitor continental scale seasonal conditions in an effective manner. As a consequence of these results, further research using this type of data is proposed in rangeland management and climate change modelling.
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González, Garcia Isabel. "Influência do clima nas variações estacionais e interanuais do indice de vegetação de diferença normalizada (NDVI) no montado português." Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5467.

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Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia
Nowadays the climate change makes more necessary the study of ecosystem dynamics. The Portuguese montado is an ecosystem with very particular characteristics, because is a combined system with pastures and forest, managed by men, and depends on this manage to continue. More than economic value, montado is very important system with a big biodiversity and landscape quality. For this study was propose to study about the seasonal variation of montado, since 2000 to 2012, using remote sensing and vegetation index as tools to analyze the response of montado to different environmental factors, as the precipitation, temperature and relative humidity. The chosen vegetation index was the NDVI (Normalized Difference Vegetation Index), because of all the advantages, and was calculated using MODIS sensor data. To find the relation between our vegetation index vegetation data, and the meteorological variables, was make a time series analysis, and a correlation study of each variable with the vegetation index. The results was satisfactory and was agree with the initial hypotheses. We find that the precipitation is the variable that influences NDVI the most, and this correlation is bigger when we use the accumulative inter-annual and seasonal data instead the original data. The results show the effects of the big drought of 2004 and 2005 too. The remote sensing appears as a very important and critical tool for this study area future and show that this study could be extend with new directions and new research hypotheses
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Jorge, Catarina Tonelo. "Phenology analysis in a cork oak woodland through digital photography and spectral vegetation indexes." Master's thesis, ISA, 2019. http://hdl.handle.net/10400.5/19543.

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Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia
Digital repeat photography is a method to monitor the phenology of vegetation that has gained momentum this past decade. As a result, the need for further case-studies is required. This work aims to prove that it is possible to use digital cameras instead of spectral information to track phenology in a Mediterranean cork oak woodland. The photos will originate the green chromatic coordinates (GCC) index while the normalized difference vegetation index (NDVI) derives from the spectral data collected with a field spectroradiometer. The results were found by employing a regular commercial camera to take monthly pictures along with the spectral measurements. They showed good agreement among methods especially for the herbaceous layer whose GCC had a very good fit with NDVI. The coefficient of determination for the herbaceous layer, the shrub cistus and shrub ulex was 0.89, 0.62 and 0.30, respectively. However, these regressions may be improved upon by grouping the shrub species. The shrubs had a lower correlation between the two indices and all three groups showed a response to water availability. For these reasons, a linear regression between GCC and the normalized water difference index (NDWI) was pursued. This second regression showed better results for shrubs, with coefficients of determination of 0.78 e 0.55, respectively, and a similar value for the herbaceous layer (0.84). The herbaceous layer was found to react quickly to water. Because it only has access to superficial water, its phenology is dependent on precipitation. This group had a good outcome with more long-term observations than shrubs (eight years of data vs. three years). So, it would be the most suitable plant functional type to be tracked using the digital repeat photography method coupled with GCC. Nonetheless, using photos and GCC proves to have the potential to monitor a wide spectrum of vegetation types
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JULITTA, TOMMASO. "Optical proximal sensing for vegetation monitoring." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2015. http://hdl.handle.net/10281/70505.

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Monitoring vegetation dynamics represents a fundamental practice to evaluate the response of the vegetation to environmental changes. Optical proximal sensed data allow the monitoring of the temporal and spatial variability of vegetation properties under natural conditions. Vegetation optical properties can be used to indirectly derive information about the phenological and/or physiological status of the plants. Optical sensors commonly used in the field can be divided into broadband sensors (usually multispectral, e.g. RGB cameras) and narrowband sensors (both multispectral and hyperspectral devices, e.g. spectroradiometers). The potential applications of these two categories of sensors differ. While broadband sensors have been applied in the last years to track the phenological development of the vegetation, spectroradiometers have been shown to be suitable also for the characterization of plant physiological status. In fact hyperspectral systems provide a more detailed optical characterization of the analysed targets, nevertheless the systems have to be accurately characterized in terms of spectral and radiometric performances in order to obtain repeatable and comparable. The first part of the research has been addressed to the determination of the sources of uncertainty of the optical measurement systems. Several of the most common optical devices available on the market have been characterized and compared. A particular attention has been paid to instrumental differences in the optical components which could affect the radiance measurements. Moreover the performances of spectroradiometers have been evaluated both indoors and outdoors in order to evaluate the impact of sensor characteristics on the estimation of parameters commonly used in vegetation studies. The analysis has been initially focused on the effect of different cosine receptors on the estimation of biochemical and biophysical properties of the vegetation, such as leaf area index and chlorophyll content. In a second step the analysis referred to the impact of instrumental characteristics (mainly spectral resolution and signal to noise ratio) on the estimation of the absolute value of sun-induced chlorophyll fluorescence. The results obtained suggest that instrument components affect the measurements and according to the required parameter estimations accuracy some instruments are more suitable rather than others. The second part of the study has been focused on the use of proximal sensors to monitor the dynamics of terrestrial vegetation. For this purpose both broadband and narrowband sensors have been separately considered. The first analysis referred to the possibility of using broadband imaging systems to investigate the temporal and spatial phenological dynamics of an alpine ecosystem. The phenological analysis has been conducted using a 3-year time series of digital RGB images collected in a grassland site. This spatiotemporal analysis provided interesting insights into the role of plant species composition on phenology in complex ecosystems, such as alpine grasslands. This study case indicates the potential of using RGB digital cameras as a tool for long term phenological monitoring, allowing the spatial characterization of the investigated ecosystem. The possibility of using hyperspectral narrowband sensors to detect vegetation physiological changes was also evaluated. In particular, this analysis focused on the use of sun-induced chlorophyll fluorescence for the early detection of vegetation stress. The study was conducted during a controlled experiment designed to modify the functional status of actual photosynthesis. The results indicate that fluorescence is immediately affected by physiological changes as a demonstration that such estimates can be used to track physiological traits better than traditional remote sensing techniques based on optical broadband vegetation indices.
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Eklund, Carl. "Ståndortsfaktorer och vegetation : En problematiserande litteraturstudie." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-144161.

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Ståndort är ett område där ett bestånd av en viss växt finns, ofta avses träd inom skogsproduktion. Förutsättningarna för detta, ståndortsfaktorer, återfinns i markens egenskaper (edafiska faktorer) och klimatet. Dessa påverkar därigenom växtens produktion, något som särskilt är av intresse inom skogsbruket och de skogliga vetenskaperna. Till detta kommer att växter samspelar med andra växter och organismer såsom svampar, bakterier och djur, och även den antropogena påverkan med faktorer såsom husdjursbete, atmosfäriskt nedfall och skogsproduktion har en stark inverkan på vegetationen. Utifrån att studera några av de mer kända teorierna om växtsamhällen och -strategier samt olika vinklar av ståndortsfaktorer var hypotesen att det går att få fram en problematiserande bild och hitta störfaktorer (confoundingvariabler), som kan ge felaktiga tolkningar av resultat. Ett antal kända verk inom vegetationsklassificering gicks igenom, kompletterat med stödjande litteratur. En artikelsökning genomfördes också, med kombinationer av specifika sökord med anknytning till ståndort. För att begränsa urvalet och ge en mer regional prägel på arbetet ställdes sökfiltren i artikelsökningen in på att enbart visa resultat från Skandinavien och Finland. Artiklarna delades in efter teman och behandlades efter dessa. Även om få huvudsakliga faktorer styr vegetationen finns flera variabler som lokalt har en stor betydelse, såsom snö, genetiska egenskaper och symbios med andra organismer. Dessa variabler kan vara svåra att mäta och det finns mycket på detaljnivå som är dåligt undersökt. Markanvändningar påverkar de edafiska faktorerna långt efter att brukandet ändrats eller upphört, men detta har olika stor lokal påverkan. Kvävets och kolets halter och cykler är återkommande osäkerhetsfaktorer i artiklarna, där det atmosfäriska kvävenedfallet spelar en viktig men ojämn roll, och jämförbara mätningar försvåras av skillnader i väder och klimat. Till detta kommer påverkan av markorganismer, vilka har en mycket viktig del i växternas näringsupptag, men är svår att mäta. Även om alla aspekter av en växtplats inte kan tas med bör fler felkällor tas i beaktande och modeller ha möjlighet att kalibreras mot olika teorier om växtsamhällen och -strategier. Flera faktorer som traditionellt inte räknas som ståndortsfaktorer, såsom snödjup, symbios med markorganismer och markanvändning, kan vara betydelsefulla att ta med i exempelvis modellering.
A site is an area where a population of a specific plant species has its habitat, often the connotation is forestry. The prerequisites for this, the site indices (also site variables or stand variables), can be found in the characteristics of the ground (edaphic factors) as well as the climatic impact. These elements affect the growth and production, which is of interest in forestry and forest sciences. Upon this the plants interact with each other as well as with other organisms, i.e. fungi, bacteria and animals, and there is also an anthropogenic impact where factors such as livestock grazing, atmospheric deposition and forest production strongly affects the vegetation. By studying some of the more prominent theories on vegetation societies/sociologies and plant strategies, as well as different aspects of the site concept, the hypothesis was that a problematizing picture of site indices can be found and some confounding variables that can give erroneous interpretation of results. A number of major works in vegetation classification was gone through, supplemented by supporting literature. An article search was conducted to find journal articles, using combinations of specific search terms related to site indices. To narrow down the results and give a more regional touch to the thesis, the filter was set only to show results from Scandinavia and Finland. The articles were grouped into themes and handled theme-wise. Even though there are few principal factors controlling the vegetation there are a number of variables which locally can have a large impact, such as snow, genetic traits and symbiosis. These variables can be hard to measure, and a lot of things at a detailed level are poorly investigated. Land use modifies the edaphic properties long after the usage have changed or been discontinued. The amounts and cycles of nitrogen and carbon are recurrent uncertainties in the articles, where deposits of nitrogen from the atmosphere plays an important but uneven role and measurements can be hard to compare due to differences in weather and climate. Added to this, organisms in the ground have a major role in the plants’ nutrient uptake, but the effects can be hard to study. A concluding remark is that even though all aspects of a site cannot always be included more confounding variables could be taken in account and models should be able to be calibrated to different theories on vegetation societies/sociologies and plant strategies. Many factors normally not counted as site indices, i.e. snow depth, soil biota symbiosis, and land use, could be valuable to include in e.g. modelling.
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8

Hammer, Rachel Lynn. "Soil Respiration and Related Abiotic and Remotely Sensed Variables in Different Overstories and Understories in a High Elevation Southern Appalachian Forest." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/93272.

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Forests have the ability to sequester carbon from our atmosphere. Soil respiration (Rs) plays a role in a forest's ability to do so as it is a significant source of carbon dioxide back to the atmosphere. Therefore, understanding the process of Rs under varying conditions is gaining more attention. As of now we have a relatively good understanding of Rs under managed forest ecosystems such as pine plantations. This particular study examined Rs under different overstories and understories in a high elevation Southern Appalachian forest in order to get a better understanding of Rs under a natural hardwood system. The four vegetation types under consideration were an eastern hemlock (Tsuga canadensis L. Carriere) dominated overstory, a hardwood overstory with little to no understory, a mountain laurel (Kalmia latifolia L.) dominated understory, and a cinnamon fern (Osmundastrum cinnamomeum (L.) C.Presl) dominated understory. Differing temporal variations of Rs were observed under the vegetation types. We found monthly differences in rates among vegetation type however, an overall annual difference in Rs rates between vegetation types was not observed. This simply indicates the importance of observing Rs under different time scales to get a better understanding of its variation. We also calculated vegetation indices from remotely-sensed data to explore any relationships to Rs as well as if the indices themselves could improve out model. A vegetation index is a number that is calculated for every pixel in a remotely sensed image and represents plant vigor or abundance. Few significant relationships were found between the indices and Rs. Future work may want to better understand vegetation indices' spatial extent and accuracy in order to find whether they may be beneficial in Rs estimation. Understanding the influence of varying vegetation type and soil temperature and moisture on Rs will ultimately improve our ability to predict what drives changes in carbon fluxes.
Master of Science
Forests have the ability to sequester carbon from our atmosphere. Soil respiration (Rs) plays a role in a forest’s ability to do so as it is a significant source of carbon dioxide back to the atmosphere. Therefore, understanding the process of Rs under varying conditions is gaining more attention. As of now we have a relatively good understanding of Rs under managed forest ecosystems such as pine plantations. This particular study examined Rs under different overstories and understories in a high elevation Southern Appalachian forest in order to get a better understanding of Rs under a natural hardwood system. The four vegetation types under consideration were an eastern hemlock (Tsuga canadensis L. Carriere) dominated overstory, a hardwood overstory with little to no understory, a mountain laurel (Kalmia latifolia L.) dominated understory, and a cinnamon fern (Osmundastrum cinnamomeum (L.) C.Presl) dominated understory. Differing temporal variations of Rs were observed under the vegetation types. We found monthly differences in rates among vegetation type however, an overall annual difference in Rs rates between vegetation types was not observed. This simply indicates the importance of observing Rs under different time scales to get a better understanding of its variation. We also calculated vegetation indices from remotely-sensed data to explore any relationships to Rs as well as if the indices themselves could improve out model. A vegetation index is a number that is calculated for every pixel in a remotely sensed image and represents plant vigor or abundance. Few significant relationships were found between the indices and Rs. Future work may want to better understand vegetation indices’ spatial extent and accuracy in order to find whether they may be beneficial in Rs estimation. Understanding the influence of varying vegetation type and soil temperature and moisture on Rs will ultimately improve our ability to predict what drives changes in carbon fluxes.
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9

Noumonvi, Koffi Dodji. "Estimation of carbon fluxes from eddy covariance data and satellite-derived vegetation indices in a karst grassland (Podgorski Kras, Slovenia)." Master's thesis, ISA/UL, 2018. http://hdl.handle.net/10400.5/17944.

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Mestrado MEDfOR - Mediterranean Forestry and Natural Resources Management - Instituto Superior de Agronomia
The Eddy covariance method is a widespread method used for measuring carbon fluxes between the atmosphere and the ecosystem. It provides a high temporal resolution of measurements, but it is restricted to an area around the tower called footprint, and other methods are usually used in combination with eddy covariance data in order to estimate carbon fluxes for larger areas. Spectral vegetation indices derived from increasingly available satellite data can be combined with eddy covariance data to estimate carbon fluxes outside of the tower footprint. Following that approach, the present study attempted to model carbon fluxes for a karst grassland in Slovenia. Three types of model were considered: (1) a linear relationship between NEE or GPP and each vegetation index, (2) a linear relationship between GPP and the product of a vegetation index with PAR, and (3) a simplified LUE model assuming a constant LUE. We compared the performance of several vegetation indices from two sources (Landsat and SPOT-Vegetation) as predictors of NEE and GPP, based on three accuracy metrics (R², RMSE and AIC). Two types of aggregation of flux data were explored, midday average fluxes and daily average fluxes. The Vapor Pressure Deficit was used to separate the growing season in two phases, a greening phase and a dry phase, which were considered separately in the modelling process, in addition to the growing season as a whole. The results showed that NDVI was the best predictor of GPP and NEE during the greening phase, whereas water related vegetation indices, namely LSWI and MNDWI were the best predictors during the dry phase, both for midday and daily aggregates. Model type 1 (linear relationship) was found to be the best in many cases. The best regression equations obtained were used to illustrate the mapping of GPP and NEE for the study area
N/A
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10

Weiss, Marie. "DEVELOPPEMENT D'UN ALGORITHME DE SUIVI DE LA VEGETATION A LARGE ECHELLE." Phd thesis, Université de Nice Sophia-Antipolis, 1998. http://tel.archives-ouvertes.fr/tel-00707683.

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L'objectif de ce travail est de développer un algorithme utilisant des réseaux neuronaux pour estimer des variables biophysiques des couverts végétaux à partir des données du capteur VEGETATION : la fraction de trou dans différentes directions de visée, l'indice foliaire, la fraction de rayonnement photosynthétiquement actif absorbé par le couvert, l'angle moyen d'inclinaison des feuilles, et la teneur en chlorophylle intégrée au niveau du couvert. Une base de données a été élaborée à partir de simulations de modèles de transfert radiatif dans la végétation. Ceci nous a permis de développer des réseaux de neurones pour estimer les différentes variables biophysiques considérées. L'estimation se fait à partir des réflectances bidirectionnelles mesurées par VEGETATION durant un cycle orbital, associées à l'angle zénithal solaire lors de l'acquisition de ces données. L'analyse de sensibilité à l'hétérogénéité intrapixellaire montre que les variables de type fraction de trou et fAPAR sont beaucoup moins sensibles que les variables de type LAI. La validation de l'algorithme sur des données expérimentales montre la robustesse de la méthode lorsque le nombre de données bidirectionnelles acquises durant le cycle orbital est faible. Par ailleurs, elle confirme que les performances d'estimation des variables biophysiques sont affectées non seulement par la représentativité du couvert et des conditions d'observation qui lui sont associées dans la base d'apprentissage, mais aussi par les hypothèses inhérentes aux modèles de transfert radiatif utilisés pour générer cette base. Nous mettons également en évidence la sensibilité de l'algorithme à des bruits de natures diverses (mesure, correction atmosphérique, ...). Les résultats obtenus sur les données expérimentales sont satisfaisants et aboutissent à un écart quadratique moyen inférieur à 0,1. L'intérêt des réseaux de neurones apparaît donc clairement, en particulier vis à vis des approches basées sur les indices de végétation.
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Books on the topic "Vegetation indece"

1

Payandeh, Bijan. Predictability of site index from soil factors and lesser vegetation in northern Ontario forest types. Sault Ste. Marie, Ont: Great Lakes Forestry Centre, 1986.

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2

Ergo, A. B. Indices climatiques et applications en analogie agrobioclimatique. Tervuren, Belgique: Musée royal de l'Afrique centrale, 1989.

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3

United States. National Aeronautics and Space Administration., ed. Peat landforms along the Albany River, northern Ontario: An ecologic study of peat landforms in Canada and Alaska : a progress report. [Washington, DC: National Aeronautics and Space Administration, 1985.

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4

Lézine, Anne-Marie. Vegetation at the Time of the African Humid Period. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.530.

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An orbitally induced increase in summer insolation during the last glacial-interglacial transition enhanced the thermal contrast between land and sea, with land masses heating up compared to the adjacent ocean surface. In North Africa, warmer land surfaces created a low-pressure zone, driving the northward penetration of monsoonal rains originating from the Atlantic Ocean. As a consequence, regions today among the driest of the world were covered by permanent and deep freshwater lakes, some of them being exceptionally large, such as the “Mega” Lake Chad, which covered some 400 000 square kilometers. A dense network of rivers developed.What were the consequences of this climate change on plant distribution and biodiversity? Pollen grains that accumulated over time in lake sediments are useful tools to reconstruct past vegetation assemblages since they are extremely resistant to decay and are produced in great quantities. In addition, their morphological character allows the determination of most plant families and genera.In response to the postglacial humidity increase, tropical taxa that survived as strongly reduced populations during the last glacial period spread widely, shifting latitudes or elevations, expanding population size, or both. In the Saharan desert, pollen of tropical trees (e.g., Celtis) were found in sites located at up to 25°N in southern Libya. In the Equatorial mountains, trees (e.g., Olea and Podocarpus) migrated to higher elevations to form the present-day Afro-montane forests. Patterns of migration were individualistic, with the entire range of some taxa displaced to higher latitudes or shifted from one elevation belt to another. New combinations of climate/environmental conditions allowed the cooccurrences of taxa growing today in separate regions. Such migrational processes and species-overlapping ranges led to a tremendous increase in biodiversity, particularly in the Saharan desert, where more humid-adapted taxa expanded along water courses, lakes, and wetlands, whereas xerophytic populations persisted in drier areas.At the end of the Holocene era, some 2,500 to 4,500 years ago, the majority of sites in tropical Africa recorded a shift to drier conditions, with many lakes and wetlands drying out. The vegetation response to this shift was the overall disruption of the forests and the wide expansion of open landscapes (wooded grasslands, grasslands, and steppes). This environmental crisis created favorable conditions for further plant exploitation and cereal cultivation in the Congo Basin.
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5

Claussen, Martin, Anne Dallmeyer, and Jürgen Bader. Theory and Modeling of the African Humid Period and the Green Sahara. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.532.

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There is ample evidence from palaeobotanic and palaeoclimatic reconstructions that during early and mid-Holocene between some 11,700 years (in some regions, a few thousand years earlier) and some 4200 years ago, subtropical North Africa was much more humid and greener than today. This African Humid Period (AHP) was triggered by changes in the orbital forcing, with the climatic precession as the dominant pacemaker. Climate system modeling in the 1990s revealed that orbital forcing alone cannot explain the large changes in the North African summer monsoon and subsequent ecosystem changes in the Sahara. Feedbacks between atmosphere, land surface, and ocean were shown to strongly amplify monsoon and vegetation changes. Forcing and feedbacks have caused changes far larger in amplitude and extent than experienced today in the Sahara and Sahel. Most, if not all, climate system models, however, tend to underestimate the amplitude of past African monsoon changes and the extent of the land-surface changes in the Sahara. Hence, it seems plausible that some feedback processes are not properly described, or are even missing, in the climate system models.Perhaps even more challenging than explaining the existence of the AHP and the Green Sahara is the interpretation of data that reveal an abrupt termination of the last AHP. Based on climate system modeling and theoretical considerations in the late 1990s, it was proposed that the AHP could have ended, and the Sahara could have expanded, within just a few centuries—that is, much faster than orbital forcing. In 2000, paleo records of terrestrial dust deposition off Mauritania seemingly corroborated the prediction of an abrupt termination. However, with the uncovering of more paleo data, considerable controversy has arisen over the geological evidence of abrupt climate and ecosystem changes. Some records clearly show abrupt changes in some climate and terrestrial parameters, while others do not. Also, climate system modeling provides an ambiguous picture.The prediction of abrupt climate and ecosystem changes at the end of the AHP is hampered by limitations implicit in the climate system. Because of the ubiquitous climate variability, it is extremely unlikely that individual paleo records and model simulations completely match. They could do so in a statistical sense, that is, if the statistics of a large ensemble of paleo data and of model simulations converge. Likewise, the interpretation regarding the strength of terrestrial feedback from individual records is elusive. Plant diversity, rarely captured in climate system models, can obliterate any abrupt shift between green and desert state. Hence, the strength of climate—vegetation feedback is probably not a universal property of a certain region but depends on the vegetation composition, which can change with time. Because of spatial heterogeneity of the African landscape and the African monsoon circulation, abrupt changes can occur in several, but not all, regions at different times during the transition from the humid mid-Holocene climate to the present-day more arid climate. Abrupt changes in one region can be induced by abrupt changes in other regions, a process sometimes referred to as “induced tipping.” The African monsoon system seems to be prone to fast and potentially abrupt changes, which to understand and to predict remains one of the grand challenges in African climate science.
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Wilsey, Brian J. Factors Maintaining and Regulating Grassland Structure and Function. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198744511.003.0003.

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Intrinsic disturbances are processes that have occurred on an evolutionary time scale, and include fire, wind-damage, digging or burrowing by fossorial mammals, defoliation, and trampling by native large mammals. Grassland species evolved with intrinsic disturbances, and they can be important in maintaining grassland community structure and functioning. Adaptations to fire include short herbaceous stature, high allocation belowground, ability to resprout, and smoke-induced seed germination. Fire interacts with grazing because grazing reduces litter (fuel) load, and fires affect forage quality. Plants can tolerate some level of herbivory in most grasslands. Adaptations that enable grassland plants to resist grazing are similar to plant adaptations to fire. Drought can affect grasslands at a variety of time scales. Vegetative reproduction can allow rapid recolonization after droughts have ended. Plowing is the most common disturbance affecting grasslands, and it has been used to transform native grasslands into crop fields and simplified pasture.
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Schmidt-Thomé, Philipp. Climate Change Adaptation. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.635.

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Climate change adaptation is the ability of a society or a natural system to adjust to the (changing) conditions that support life in a certain climate region, including weather extremes in that region. The current discussion on climate change adaptation began in the 1990s, with the publication of the Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC). Since the beginning of the 21st century, most countries, and many regions and municipalities have started to develop and implement climate change adaptation strategies and plans. But since the implementation of adaptation measures must be planned and conducted at the local level, a major challenge is to actually implement adaptation to climate change in practice. One challenge is that scientific results are mainly published on international or national levels, and political guidelines are written at transnational (e.g., European Union), national, or regional levels—these scientific results must be downscaled, interpreted, and adapted to local municipal or community levels. Needless to say, the challenges for implementation are also rooted in a large number of uncertainties, from long time spans to matters of scale, as well as in economic, political, and social interests. From a human perspective, climate change impacts occur rather slowly, while local decision makers are engaged with daily business over much shorter time spans.Among the obstacles to implementing adaptation measures to climate change are three major groups of uncertainties: (a) the uncertainties surrounding the development of our future climate, which include the exact climate sensitivity of anthropogenic greenhouse gas emissions, the reliability of emission scenarios and underlying storylines, and inherent uncertainties in climate models; (b) uncertainties about anthropogenically induced climate change impacts (e.g., long-term sea level changes, changing weather patterns, and extreme events); and (c) uncertainties about the future development of socioeconomic and political structures as well as legislative frameworks.Besides slow changes, such as changing sea levels and vegetation zones, extreme events (natural hazards) are a factor of major importance. Many societies and their socioeconomic systems are not properly adapted to their current climate zones (e.g., intensive agriculture in dry zones) or to extreme events (e.g., housing built in flood-prone areas). Adaptation measures can be successful only by gaining common societal agreement on their necessity and overall benefit. Ideally, climate change adaptation measures are combined with disaster risk reduction measures to enhance resilience on short, medium, and long time scales.The role of uncertainties and time horizons is addressed by developing climate change adaptation measures on community level and in close cooperation with local actors and stakeholders, focusing on strengthening resilience by addressing current and emerging vulnerability patterns. Successful adaptation measures are usually achieved by developing “no-regret” measures, in other words—measures that have at least one function of immediate social and/or economic benefit as well as long-term, future benefits. To identify socially acceptable and financially viable adaptation measures successfully, it is useful to employ participatory tools that give all involved parties and decision makers the possibility to engage in the process of identifying adaptation measures that best fit collective needs.
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8

Verschuur, Gerrit L. Impact! Oxford University Press, 1996. http://dx.doi.org/10.1093/oso/9780195101058.001.0001.

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Most scientists now agree that some sixty-five million years ago, an immense comet slammed into the Yucatan, detonating a blast twenty million times more powerful than the largest hydrogen bomb, punching a hole ten miles deep in the earth. Trillions of tons of rock were vaporized and launched into the atmosphere. For a thousand miles in all directions, vegetation burst into flames. There were tremendous blast waves, searing winds, showers of molten matter from the sky, earthquakes, and a terrible darkness that cut out sunlight for a year, enveloping the planet in freezing cold. Thousands of species of plants and animals were obliterated, including the dinosaurs, some of which may have become extinct in a matter of hours. In Impact, Gerrit L. Verschuur offers an eye-opening look at such catastrophic collisions with our planet. Perhaps more important, he paints an unsettling portrait of the possibility of new collisions with earth, exploring potential threats to our planet and describing what scientists are doing right now to prepare for this awful possibility. Every day something from space hits our planet, Verschuur reveals. In fact, about 10,000 tons of space debris fall to earth every year, mostly in meteoric form. The author recounts spectacular recent sightings, such as over Allende, Mexico, in 1969, when a fireball showered the region with four tons of fragments, and the twenty-six pound meteor that went through the trunk of a red Chevy Malibu in Peekskill, New York, in 1992 (the meteor was subsequently sold for $69,000 and the car itself fetched $10,000). But meteors are not the greatest threat to life on earth, the author points out. The major threats are asteroids and comets. The reader discovers that astronomers have located some 350 NEAs ("Near Earth Asteroids"), objects whose orbits cross the orbit of the earth, the largest of which are 1627 Ivar (6 kilometers wide) and 1580 Betula (8 kilometers). Indeed, we learn that in 1989, a bus-sized asteroid called Asclepius missed our planet by 650,000 kilometers (a mere six hours), and that in 1994 a sixty-foot object passed within 180,000 kilometers, half the distance to the moon. Comets, of course, are even more deadly. Verschuur provides a gripping description of the small comet that exploded in the atmosphere above the Tunguska River valley in Siberia, in 1908, in a blinding flash visible for several thousand miles (every tree within sixty miles of ground zero was flattened). He discusses Comet Swift-Tuttle--"the most dangerous object in the solar system"--a comet far larger than the one that killed off the dinosaurs, due to pass through earth's orbit in the year 2126. And he recounts the collision of Comet Shoemaker-Levy 9 with Jupiter in 1994, as some twenty cometary fragments struck the giant planet over the course of several days, casting titanic plumes out into space (when Fragment G hit, it outshone the planet on the infrared band, and left a dark area at the impact site larger than the Great Red Spot). In addition, the author describes the efforts of Spacewatch and other groups to locate NEAs, and evaluates the idea that comet and asteroid impacts have been an underrated factor in the evolution of life on earth. Astronomer Herbert Howe observed in 1897: "While there are not definite data to reason from, it is believed that an encounter with the nucleus of one of the largest comets is not to be desired." As Verschuur shows in Impact, we now have substantial data with which to support Howe's tongue-in-cheek remark. Whether discussing monumental tsunamis or the innumerable comets in the Solar System, this book will enthrall anyone curious about outer space, remarkable natural phenomenon, or the future of the planet earth.
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9

Johansen, Bruce, and Adebowale Akande, eds. Nationalism: Past as Prologue. Nova Science Publishers, Inc., 2021. http://dx.doi.org/10.52305/aief3847.

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Nationalism: Past as Prologue began as a single volume being compiled by Ad Akande, a scholar from South Africa, who proposed it to me as co-author about two years ago. The original idea was to examine how the damaging roots of nationalism have been corroding political systems around the world, and creating dangerous obstacles for necessary international cooperation. Since I (Bruce E. Johansen) has written profusely about climate change (global warming, a.k.a. infrared forcing), I suggested a concerted effort in that direction. This is a worldwide existential threat that affects every living thing on Earth. It often compounds upon itself, so delays in reducing emissions of fossil fuels are shortening the amount of time remaining to eliminate the use of fossil fuels to preserve a livable planet. Nationalism often impedes solutions to this problem (among many others), as nations place their singular needs above the common good. Our initial proposal got around, and abstracts on many subjects arrived. Within a few weeks, we had enough good material for a 100,000-word book. The book then fattened to two moderate volumes and then to four two very hefty tomes. We tried several different titles as good submissions swelled. We also discovered that our best contributors were experts in their fields, which ranged the world. We settled on three stand-alone books:” 1/ nationalism and racial justice. Our first volume grew as the growth of Black Lives Matter following the brutal killing of George Floyd ignited protests over police brutality and other issues during 2020, following the police assassination of Floyd in Minneapolis. It is estimated that more people took part in protests of police brutality during the summer of 2020 than any other series of marches in United States history. This includes upheavals during the 1960s over racial issues and against the war in Southeast Asia (notably Vietnam). We choose a volume on racism because it is one of nationalism’s main motive forces. This volume provides a worldwide array of work on nationalism’s growth in various countries, usually by authors residing in them, or in the United States with ethnic ties to the nation being examined, often recent immigrants to the United States from them. Our roster of contributors comprises a small United Nations of insightful, well-written research and commentary from Indonesia, New Zealand, Australia, China, India, South Africa, France, Portugal, Estonia, Hungary, Russia, Poland, Kazakhstan, Georgia, and the United States. Volume 2 (this one) describes and analyzes nationalism, by country, around the world, except for the United States; and 3/material directly related to President Donald Trump, and the United States. The first volume is under consideration at the Texas A & M University Press. The other two are under contract to Nova Science Publishers (which includes social sciences). These three volumes may be used individually or as a set. Environmental material is taken up in appropriate places in each of the three books. * * * * * What became the United States of America has been strongly nationalist since the English of present-day Massachusetts and Jamestown first hit North America’s eastern shores. The country propelled itself across North America with the self-serving ideology of “manifest destiny” for four centuries before Donald Trump came along. Anyone who believes that a Trumpian affection for deportation of “illegals” is a new thing ought to take a look at immigration and deportation statistics in Adam Goodman’s The Deportation Machine: America’s Long History of Deporting Immigrants (Princeton University Press, 2020). Between 1920 and 2018, the United States deported 56.3 million people, compared with 51.7 million who were granted legal immigration status during the same dates. Nearly nine of ten deportees were Mexican (Nolan, 2020, 83). This kind of nationalism, has become an assassin of democracy as well as an impediment to solving global problems. Paul Krugman wrote in the New York Times (2019:A-25): that “In their 2018 book, How Democracies Die, the political scientists Steven Levitsky and Daniel Ziblatt documented how this process has played out in many countries, from Vladimir Putin’s Russia, to Recep Erdogan’s Turkey, to Viktor Orban’s Hungary. Add to these India’s Narendra Modi, China’s Xi Jinping, and the United States’ Donald Trump, among others. Bit by bit, the guardrails of democracy have been torn down, as institutions meant to serve the public became tools of ruling parties and self-serving ideologies, weaponized to punish and intimidate opposition parties’ opponents. On paper, these countries are still democracies; in practice, they have become one-party regimes….And it’s happening here [the United States] as we speak. If you are not worried about the future of American democracy, you aren’t paying attention” (Krugmam, 2019, A-25). We are reminded continuously that the late Carl Sagan, one of our most insightful scientific public intellectuals, had an interesting theory about highly developed civilizations. Given the number of stars and planets that must exist in the vast reaches of the universe, he said, there must be other highly developed and organized forms of life. Distance may keep us from making physical contact, but Sagan said that another reason we may never be on speaking terms with another intelligent race is (judging from our own example) could be their penchant for destroying themselves in relatively short order after reaching technological complexity. This book’s chapters, introduction, and conclusion examine the worldwide rise of partisan nationalism and the damage it has wrought on the worldwide pursuit of solutions for issues requiring worldwide scope, such scientific co-operation public health and others, mixing analysis of both. We use both historical description and analysis. This analysis concludes with a description of why we must avoid the isolating nature of nationalism that isolates people and encourages separation if we are to deal with issues of world-wide concern, and to maintain a sustainable, survivable Earth, placing the dominant political movement of our time against the Earth’s existential crises. Our contributors, all experts in their fields, each have assumed responsibility for a country, or two if they are related. This work entwines themes of worldwide concern with the political growth of nationalism because leaders with such a worldview are disinclined to co-operate internationally at a time when nations must find ways to solve common problems, such as the climate crisis. Inability to cooperate at this stage may doom everyone, eventually, to an overheated, stormy future plagued by droughts and deluges portending shortages of food and other essential commodities, meanwhile destroying large coastal urban areas because of rising sea levels. Future historians may look back at our time and wonder why as well as how our world succumbed to isolating nationalism at a time when time was so short for cooperative intervention which is crucial for survival of a sustainable earth. Pride in language and culture is salubrious to individuals’ sense of history and identity. Excess nationalism that prevents international co-operation on harmful worldwide maladies is quite another. As Pope Francis has pointed out: For all of our connectivity due to expansion of social media, ability to communicate can breed contempt as well as mutual trust. “For all our hyper-connectivity,” said Francis, “We witnessed a fragmentation that made it more difficult to resolve problems that affect us all” (Horowitz, 2020, A-12). The pope’s encyclical, titled “Brothers All,” also said: “The forces of myopic, extremist, resentful, and aggressive nationalism are on the rise.” The pope’s document also advocates support for migrants, as well as resistance to nationalist and tribal populism. Francis broadened his critique to the role of market capitalism, as well as nationalism has failed the peoples of the world when they need co-operation and solidarity in the face of the world-wide corona virus pandemic. Humankind needs to unite into “a new sense of the human family [Fratelli Tutti, “Brothers All”], that rejects war at all costs” (Pope, 2020, 6-A). Our journey takes us first to Russia, with the able eye and honed expertise of Richard D. Anderson, Jr. who teaches as UCLA and publishes on the subject of his chapter: “Putin, Russian identity, and Russia’s conduct at home and abroad.” Readers should find Dr. Anderson’s analysis fascinating because Vladimir Putin, the singular leader of Russian foreign and domestic policy these days (and perhaps for the rest of his life, given how malleable Russia’s Constitution has become) may be a short man physically, but has high ambitions. One of these involves restoring the old Russian (and Soviet) empire, which would involve re-subjugating a number of nations that broke off as the old order dissolved about 30 years ago. President (shall we say czar?) Putin also has international ambitions, notably by destabilizing the United States, where election meddling has become a specialty. The sight of Putin and U.S. president Donald Trump, two very rich men (Putin $70-$200 billion; Trump $2.5 billion), nuzzling in friendship would probably set Thomas Jefferson and Vladimir Lenin spinning in their graves. The road of history can take some unanticipated twists and turns. Consider Poland, from which we have an expert native analysis in chapter 2, Bartosz Hlebowicz, who is a Polish anthropologist and journalist. His piece is titled “Lawless and Unjust: How to Quickly Make Your Own Country a Puppet State Run by a Group of Hoodlums – the Hopeless Case of Poland (2015–2020).” When I visited Poland to teach and lecture twice between 2006 and 2008, most people seemed to be walking on air induced by freedom to conduct their own affairs to an unusual degree for a state usually squeezed between nationalists in Germany and Russia. What did the Poles then do in a couple of decades? Read Hlebowicz’ chapter and decide. It certainly isn’t soft-bellied liberalism. In Chapter 3, with Bruce E. Johansen, we visit China’s western provinces, the lands of Tibet as well as the Uighurs and other Muslims in the Xinjiang region, who would most assuredly resent being characterized as being possessed by the Chinese of the Han to the east. As a student of Native American history, I had never before thought of the Tibetans and Uighurs as Native peoples struggling against the Independence-minded peoples of a land that is called an adjunct of China on most of our maps. The random act of sitting next to a young woman on an Air India flight out of Hyderabad, bound for New Delhi taught me that the Tibetans had something to share with the Lakota, the Iroquois, and hundreds of other Native American states and nations in North America. Active resistance to Chinese rule lasted into the mid-nineteenth century, and continues today in a subversive manner, even in song, as I learned in 2018 when I acted as a foreign adjudicator on a Ph.D. dissertation by a Tibetan student at the University of Madras (in what is now in a city called Chennai), in southwestern India on resistance in song during Tibet’s recent history. Tibet is one of very few places on Earth where a young dissident can get shot to death for singing a song that troubles China’s Quest for Lebensraum. The situation in Xinjiang region, where close to a million Muslims have been interned in “reeducation” camps surrounded with brick walls and barbed wire. They sing, too. Come with us and hear the music. Back to Europe now, in Chapter 4, to Portugal and Spain, we find a break in the general pattern of nationalism. Portugal has been more progressive governmentally than most. Spain varies from a liberal majority to military coups, a pattern which has been exported to Latin America. A situation such as this can make use of the term “populism” problematic, because general usage in our time usually ties the word into a right-wing connotative straightjacket. “Populism” can be used to describe progressive (left-wing) insurgencies as well. José Pinto, who is native to Portugal and also researches and writes in Spanish as well as English, in “Populism in Portugal and Spain: a Real Neighbourhood?” provides insight into these historical paradoxes. Hungary shares some historical inclinations with Poland (above). Both emerged from Soviet dominance in an air of developing freedom and multicultural diversity after the Berlin Wall fell and the Soviet Union collapsed. Then, gradually at first, right wing-forces began to tighten up, stripping structures supporting popular freedom, from the courts, mass media, and other institutions. In Chapter 5, Bernard Tamas, in “From Youth Movement to Right-Liberal Wing Authoritarianism: The Rise of Fidesz and the Decline of Hungarian Democracy” puts the renewed growth of political and social repression into a context of worldwide nationalism. Tamas, an associate professor of political science at Valdosta State University, has been a postdoctoral fellow at Harvard University and a Fulbright scholar at the Central European University in Budapest, Hungary. His books include From Dissident to Party Politics: The Struggle for Democracy in Post-Communist Hungary (2007). Bear in mind that not everyone shares Orbán’s vision of what will make this nation great, again. On graffiti-covered walls in Budapest, Runes (traditional Hungarian script) has been found that read “Orbán is a motherfucker” (Mikanowski, 2019, 58). Also in Europe, in Chapter 6, Professor Ronan Le Coadic, of the University of Rennes, Rennes, France, in “Is There a Revival of French Nationalism?” Stating this title in the form of a question is quite appropriate because France’s nationalistic shift has built and ebbed several times during the last few decades. For a time after 2000, it came close to assuming the role of a substantial minority, only to ebb after that. In 2017, the candidate of the National Front reached the second round of the French presidential election. This was the second time this nationalist party reached the second round of the presidential election in the history of the Fifth Republic. In 2002, however, Jean-Marie Le Pen had only obtained 17.79% of the votes, while fifteen years later his daughter, Marine Le Pen, almost doubled her father's record, reaching 33.90% of the votes cast. Moreover, in the 2019 European elections, re-named Rassemblement National obtained the largest number of votes of all French political formations and can therefore boast of being "the leading party in France.” The brutality of oppressive nationalism may be expressed in personal relationships, such as child abuse. While Indonesia and Aotearoa [the Maoris’ name for New Zealand] hold very different ranks in the United Nations Human Development Programme assessments, where Indonesia is classified as a medium development country and Aotearoa New Zealand as a very high development country. In Chapter 7, “Domestic Violence Against Women in Indonesia and Aotearoa New Zealand: Making Sense of Differences and Similarities” co-authors, in Chapter 8, Mandy Morgan and Dr. Elli N. Hayati, from New Zealand and Indonesia respectively, found that despite their socio-economic differences, one in three women in each country experience physical or sexual intimate partner violence over their lifetime. In this chapter ther authors aim to deepen understandings of domestic violence through discussion of the socio-economic and demographic characteristics of theit countries to address domestic violence alongside studies of women’s attitudes to gender norms and experiences of intimate partner violence. One of the most surprising and upsetting scholarly journeys that a North American student may take involves Adolf Hitler’s comments on oppression of American Indians and Blacks as he imagined the construction of the Nazi state, a genesis of nationalism that is all but unknown in the United States of America, traced in this volume (Chapter 8) by co-editor Johansen. Beginning in Mein Kampf, during the 1920s, Hitler explicitly used the westward expansion of the United States across North America as a model and justification for Nazi conquest and anticipated colonization by Germans of what the Nazis called the “wild East” – the Slavic nations of Poland, the Baltic states, Ukraine, and Russia, most of which were under control of the Soviet Union. The Volga River (in Russia) was styled by Hitler as the Germans’ Mississippi, and covered wagons were readied for the German “manifest destiny” of imprisoning, eradicating, and replacing peoples the Nazis deemed inferior, all with direct references to events in North America during the previous century. At the same time, with no sense of contradiction, the Nazis partook of a long-standing German romanticism of Native Americans. One of Goebbels’ less propitious schemes was to confer honorary Aryan status on Native American tribes, in the hope that they would rise up against their oppressors. U.S. racial attitudes were “evidence [to the Nazis] that America was evolving in the right direction, despite its specious rhetoric about equality.” Ming Xie, originally from Beijing, in the People’s Republic of China, in Chapter 9, “News Coverage and Public Perceptions of the Social Credit System in China,” writes that The State Council of China in 2014 announced “that a nationwide social credit system would be established” in China. “Under this system, individuals, private companies, social organizations, and governmental agencies are assigned a score which will be calculated based on their trustworthiness and daily actions such as transaction history, professional conduct, obedience to law, corruption, tax evasion, and academic plagiarism.” The “nationalism” in this case is that of the state over the individual. China has 1.4 billion people; this system takes their measure for the purpose of state control. Once fully operational, control will be more subtle. People who are subject to it, through modern technology (most often smart phones) will prompt many people to self-censor. Orwell, modernized, might write: “Your smart phone is watching you.” Ming Xie holds two Ph.Ds, one in Public Administration from University of Nebraska at Omaha and another in Cultural Anthropology from the Chinese Academy of Social Sciences, Beijing, where she also worked for more than 10 years at a national think tank in the same institution. While there she summarized news from non-Chinese sources for senior members of the Chinese Communist Party. Ming is presently an assistant professor at the Department of Political Science and Criminal Justice, West Texas A&M University. In Chapter 10, analyzing native peoples and nationhood, Barbara Alice Mann, Professor of Honours at the University of Toledo, in “Divide, et Impera: The Self-Genocide Game” details ways in which European-American invaders deprive the conquered of their sense of nationhood as part of a subjugation system that amounts to genocide, rubbing out their languages and cultures -- and ultimately forcing the native peoples to assimilate on their own, for survival in a culture that is foreign to them. Mann is one of Native American Studies’ most acute critics of conquests’ contradictions, and an author who retrieves Native history with a powerful sense of voice and purpose, having authored roughly a dozen books and numerous book chapters, among many other works, who has traveled around the world lecturing and publishing on many subjects. Nalanda Roy and S. Mae Pedron in Chapter 11, “Understanding the Face of Humanity: The Rohingya Genocide.” describe one of the largest forced migrations in the history of the human race, the removal of 700,000 to 800,000 Muslims from Buddhist Myanmar to Bangladesh, which itself is already one of the most crowded and impoverished nations on Earth. With about 150 million people packed into an area the size of Nebraska and Iowa (population less than a tenth that of Bangladesh, a country that is losing land steadily to rising sea levels and erosion of the Ganges river delta. The Rohingyas’ refugee camp has been squeezed onto a gigantic, eroding, muddy slope that contains nearly no vegetation. However, Bangladesh is majority Muslim, so while the Rohingya may starve, they won’t be shot to death by marauding armies. Both authors of this exquisite (and excruciating) account teach at Georgia Southern University in Savannah, Georgia, Roy as an associate professor of International Studies and Asian politics, and Pedron as a graduate student; Roy originally hails from very eastern India, close to both Myanmar and Bangladesh, so he has special insight into the context of one of the most brutal genocides of our time, or any other. This is our case describing the problems that nationalism has and will pose for the sustainability of the Earth as our little blue-and-green orb becomes more crowded over time. The old ways, in which national arguments often end in devastating wars, are obsolete, given that the Earth and all the people, plants, and other animals that it sustains are faced with the existential threat of a climate crisis that within two centuries, more or less, will flood large parts of coastal cities, and endanger many species of plants and animals. To survive, we must listen to the Earth, and observe her travails, because they are increasingly our own.
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Book chapters on the topic "Vegetation indece"

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Seraj, Zeba I., M. Bakhtiar Hossain, Noorain M. Rasul, Hasina Akhter, Haseena Khan, Shamim Hossain, M. A. Salam, and Glenn Gregorio. "Agrobacterium-mediated transformation of Bangladesh indica for conferring salt tolerance." In Tasks for vegetation science, 167–76. Dordrecht: Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-017-0067-2_18.

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Diezma Iglesias, Belén. "Proximal vegetation sensors." In Manuali – Scienze Tecnologiche, 14. Florence: Firenze University Press, 2020. http://dx.doi.org/10.36253/978-88-5518-044-3.14.

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In this topic the basic principles of sensors to gather information about plant status are explained. Mainly optical sensors, but also systems based or other principles, vegetation sensors will be presented as well as their use to register information about crop health, physiological activity, possible pest infestation, water content, and so on. Information acquired by these sensors (normally optical signals) must be processed adequately and, in many cases, converted into vegetation indexes that will be presented for different cases of usage.
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Thompson, Keith, Clive Howard-Williams, and David Mitchell. "A cross-indexed bibliography of African wetland plants and vegetation." In The ecology and management of African wetland vegetation, 237–316. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5504-2_10.

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Kalsnes, Bjørn, and Vittoria Capobianco. "Use of Vegetation for Landslide Risk Mitigation." In Springer Climate, 77–85. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-86211-4_10.

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AbstractLandslide risk management involves several activities, modelling being a required premise for most of them. Modelling of climate-induced landslides include both the analysis of the triggering process, i.e. static slope stability analysis and dynamic propagation (run-out) analysis. These analyses are vital for mapping purposes, as well as for selection of effective means to reduce the landslide risk when this exceeds a certain value of tolerance. With the prospect of increasing rainfall duration and intensity in parts of Europe, the need for further development of modelling tools is evident. In recent years, the use of Nature-Based Solutions (NBS) for mitigation of natural hazards has further demonstrated the need for developing the modelling tools. The use of vegetation as NBS is increasingly being used for erosion protection and shallow landslide mitigation. For slope stability analyses, the use of vegetation makes the modelling more complex for a number of reasons, mostly linked to the influence of vegetation on both the soil–atmosphere interaction (i.e. rainfall interception, evapotranspiration) and the soil hydro-mechanical properties. All effects that are difficult to model due to lack of knowledge and to large variations in time and space. Even though there is an increasing activity in the geotechnical environment to incorporate the effects of vegetation in the modelling for quantifying the change in slope stability (i.e. calculate slope safety factor), the status is far from being at the level of traditional landslide modelling tools. More efforts are therefore needed in the years to come to demonstrate that the use of vegetation as a viable and effective measure in landslide risk mitigation management can be verified in a more quantifiable manner.
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Sánchez-de-Miguel, Patricia, Pilar Baeza, Pedro Junquera, and José Ramón Lissarrague. "Vegetative Development: Total Leaf Area and Surface Area Indexes." In Methodologies and Results in Grapevine Research, 31–44. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9283-0_3.

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Santos, Lorena A., Rolf E. O. Simoes, Karine R. Ferreira, Gilberto R. de Queiroz, Gilberto Camara, and Rafael D. C. Santos. "Clustering Methods to Asses Land Cover Samples of MODIS Vegetation Indexes Time Series." In Computational Science and Its Applications – ICCSA 2017, 662–73. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62407-5_48.

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Qamer, Faisal Mueen, Mir A. Matin, Ben Zaitchik, Kiran Shakya, Yi Fan, Nishanta Khanal, Walter Lee Ellenburg, et al. "A Regional Drought Monitoring and Outlook System for South Asia." In Earth Observation Science and Applications for Risk Reduction and Enhanced Resilience in Hindu Kush Himalaya Region, 59–78. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-73569-2_4.

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AbstractThe Regional Drought Monitoring and Outlook System (RDMOS) is an operational service which produces reliable drought indicators for the south Asia region with a specific focus on Afghanistan, Bangladesh, Nepal, and Pakistan. The system incorporates climatic models with suitable Earth observation data and land surface models to produce drought indices—precipitation, temperature, soil moisture, evapotranspiration—and vegetation conditions at 10-day intervals for near realtime monitoring of droughts. The RDMOS also provides seasonal outlooks at four-month intervals to support drought management and preparedness processes.
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Marques da Silva, José Rafael, and Manuela Correia. "The soil-water-plant agrisystem:a little about soil, water and plants." In Manuali – Scienze Tecnologiche, 7. Florence: Firenze University Press, 2020. http://dx.doi.org/10.36253/978-88-5518-044-3.07.

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Soil and water are essential for plants to grow. By analysing a Vegetation Index map of a corn field after emergency we are going to observe different concentrations of chlorophyll across the field. We will try to identify possible causes for those differences and discuss the strategies to solve any problems that are occurring. These problems can be related with soil characteristics, irrigation, plant germination capacity, nutrition, etc., highlighting the importance of soil-water-plant agrisystem.
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Grondin, Pierre, Marie-Hélène Brice, Yan Boulanger, Claude Morneau, Pierre-Luc Couillard, Pierre J. H. Richard, Aurélie Chalumeau, and Véronique Poirier. "Ecological Classification in Forest Ecosystem Management: Links Between Current Practices and Future Climate Change in a Québec Case Study." In Advances in Global Change Research, 219–46. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-15988-6_8.

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AbstractClimate change is expected to profoundly impact boreal forests, ranging from changes in forest composition and productivity to modifications in disturbance regimes. These climate-induced changes represent a major challenge for forest ecosystem management, as information based on ecological classification may no longer provide a straightforward guide for attaining management goals in the future. In this chapter, we examine how climate change could influence the use of ecological classification and by what means this approach can continue to be relevant for guiding the ongoing development of management practices. We address these questions by first describing ecological classification, using the example of Québec’s classification system, and then showing its importance in forest ecosystem management. Using a forest landscape in Québec as a case study, we then look at how climate change could affect boreal forest ecosystems by presenting a detailed, multistep analysis that considers climate analogs, habitat suitability, and changes in forest composition. We show that at the end of the century, the vegetation of the Abies-Betula western subdomain will not change sufficiently to resemble that of its climate analog, currently located ~500 km to the south. Changes in fire frequency and severity could significantly modify forest dynamics and composition. Consequently, the potential vegetation and the successional pathways defined under the current climate could change and follow new successional trajectories. This possible reality forces us to question some fundamental aspects of ecological classification. However, we argue that ecological classification can still provide a valuable framework for future forest management, particularly in continuing to recognize the various types of ecosystems present along toposequences. Given the changes expected in forest vegetation composition and dynamics, future variability and uncertainty must be integrated into the current stable classification units and predictable successional trajectories of ecological classification.
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Koutsias, Nikos, Iliana Kalogeropoulou, Anastasia Karamitsou, Nikoletta G. Mili, and Magdalini Pleniou. "A rule-based semi-automatic method to map burned areas using Landsat and Sentinel-2 images – incorporating vegetation indices into the mapping algorithm." In Advances in Forest Fire Research 2022, 55–57. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_7.

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At local or regional scales, where Landsat has been extensively applied to monitor burned areas, semi- or fully-automated methods are not very common. Koutsias et al. (2013) developed and improved (2021) a semi-automatic method to map burned areas consisted of a set of rules that are valid especially when the post-fire image has been captured shortly after the fire. However, the rule-based approach is not free of errors that eventually create limitations to adopt this method for reconstructing the fire history in a fully automated mode. In this work, we improved the method by incorporating vegetation indices. The vegetation indices evaluated were the: (i) Normalized Difference Vegetation Index (NDVI), (ii) Ratio Vegetation Index (RVI), (iii) Normalized Burn Ratio (NBR), (iv) Normalized Difference Water Index (NDWI) and (v) Shortwave Infrared Water Stress Index (SIWSI).
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Conference papers on the topic "Vegetation indece"

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Gupta, Aditya, Manasa R. Behera, and Amin Heidarpour. "Numerical Modeling of Wave Damping Induced by Emerged Moving Vegetation." In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18588.

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Abstract The unprecedented risk of global warming has put the coastal population at greater risk from coastal hazards due to an increase in sea level and other storm-related activities. Coastal vegetations are one of the soft solutions that can be implemented for wave mitigation. This study aims to investigate the wave damping effect of a regular wave by emergent moving coastal vegetation. Smoothed Particle Hydrodynamics (SPH), a particle-based method is used for generating fluid particles and Differential Variational Inequality (DVI) is coupled with SPH to deal with the dynamics of moving vegetation. The 3-D numerical model is simulated using an open-source tool DualSPHysics 4.4. The model is tested for regular wave height (H) of 0.08 m, wave period (T) of 2 seconds in a water depth (d) of 0.40 and 0.45 m for two relative vegetation height (h/d) of 1.25 and 1.11 respectively. The results are validated with the experimental study for the rigid vegetation and then the model is extended for moving vegetation. The results indicate that the wave damping is overestimated in the case of rigid vegetation. Further, the application of this study can be extended for studying the tsunami hazard mitigation in the presence of coastal forest.
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Barek, Viliam, Martina Kovacova, Dusan Igaz, and Oleg Paulen. "INFLUENCE OF IRRIGATION ON THE MEASUREMENT OF SPECTRAL REFLECTANCE OF LEAVES." In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/5.1/s20.031.

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Using remote sensing functional aspects of the landscape such as energy exchange between vegetation and the atmosphere, surface reflectance or vegetation heat flux can be monitored and evaluated in detail. Multispectral imagery is used to obtain information on the condition of the vegetation and plant growth, as it allows us to obtain information on possible nutrient deficiencies, pest damage or other manifestations of abiotic stress on the plants. Each surface reflects and emits radiation at different wavelengths, making it possible to create spectral curves for each surface. The waveforms of spectral curves differ based on vegetation type or physiological state, they exhibit similar basic features. Vegetation indices are used to process the measured data. In our research we focused on the changes in the values of selected vegetation indices depending on soil moisture. Spectrometer measurements were only made in 2021 on walnut in the irrigated and non-irrigated variants. The Normalized Difference Vegetation Index (NDVI) index is influenced by the chlorophyll content of the leaves. The NDVI value increased after application of irrigation dose. In the non-irrigated variant, the values decreased with decreasing rainfall and at the beginning of August. Measurements of vegetation indices show better canopy physiology in irrigated trees that responded to changes in soil moisture. Leaf physiological condition in the nonirrigated variant was more variable. As a result of the rainfall between 12 July and 27 July, when a total of 18.7 mm of rainfall fell, the condition of the non-irrigated trees began to improve.
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GomezChova, L. "Solar induced fluorescence measurements using a field spectroradiometer." In EARTH OBSERVATION FOR VEGETATION MONITORING AND WATER MANAGEMENT. AIP, 2006. http://dx.doi.org/10.1063/1.2349354.

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González-Dugo, M. P. "Spectral Vegetation Indices For Estimating Cotton And Sugarbeet Evapotranspiration." In EARTH OBSERVATION FOR VEGETATION MONITORING AND WATER MANAGEMENT. AIP, 2006. http://dx.doi.org/10.1063/1.2349335.

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Santi, E., S. Paloscia, and P. Pampaloni. "Multifrequency microwave vegetation indexes for estimating vegetation biomass." In IGARSS 2015 - 2015 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2015. http://dx.doi.org/10.1109/igarss.2015.7327002.

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Yang, Zhengwei, Liping Di, Genong Yu, and Zeqiang Chen. "Vegetation condition indices for crop vegetation condition monitoring." In IGARSS 2011 - 2011 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2011. http://dx.doi.org/10.1109/igarss.2011.6049984.

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Tao, Jing, Jiancheng Shi, Tom Jackson, Rajat Bindlish, Jinyang Du, and Lixin Zhang. "Monitoring Vegetation Water Content Using Microwave Vegetation Indices." In IGARSS 2008 - 2008 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2008. http://dx.doi.org/10.1109/igarss.2008.4778827.

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Vercruysse, Joachim, and Greet Deruyter. "OPTIMISING VEGETATION-INPUT FOR DROUGHT ASSESSMENT WITH SENTINEL-2A DATA." In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/2.1/s10.40.

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As a consequence of climate change, in some regions, more intense rain showers go hand in hand with longer dry periods. The subsequent more and more severe droughts can have devastating effects on many economic and social sectors. Therefore, it is necessary to be able to predict and assess the consequences of these droughts on a local scale, in order to develop policies to cope. Drought assessment needs a lot of detailed and accurate input-data, such as land use, land cover, soil moisture, vegetation, evapotranspiration, etc., often obtained by continuous earth monitoring by satellites. Satellite images are generally converted into indices, of which the Normalized Difference Vegetation Index (NDVI) is one of the most widely used. It was developed for use with Landsat imagery and allows for the classification of satellite images for land use and the assessment of the vegetation�s vitality. In this research, a new composite index is presented and compared to the NDVI to be used with Sentinel-2A imagery, having higher resolution and more spectral bands than Landsat. This new composite index can be used to detect water and vegetation. Test results show that this newly developed composite index achieves a better accuracy through Support Vector Machine (SVM) classification than the widely used NDVI. Although further validation is necessary, the results promise a possible amelioration of vegetation related input data for drought assessment and management.
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Krtalic, Andrija. "ANALYSIS OF VEGETATION INDICES OF URBAN VEGETATION IN ZAGREB (CROATIA)." In 18th International Multidisciplinary Scientific GeoConference SGEM2018. Stef92 Technology, 2018. http://dx.doi.org/10.5593/sgem2018/2.3/s10.004.

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Krtalic, Andrija. "ANALYSIS OF BURNED VEGETATION RECOVERY BY MEANS OF VEGETATION INDICES." In 19th SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings. STEF92 Technology, 2019. http://dx.doi.org/10.5593/sgem2019/2.2/s10.055.

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Reports on the topic "Vegetation indece"

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Becker, Sarah, Megan Maloney, and Andrew Griffin. A multi-biome study of tree cover detection using the Forest Cover Index. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42003.

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Tree cover maps derived from satellite and aerial imagery directly support civil and military operations. However, distinguishing tree cover from other vegetative land covers is an analytical challenge. While the commonly used Normalized Difference Vegetation Index (NDVI) can identify vegetative cover, it does not consistently distinguish between tree and low-stature vegetation. The Forest Cover Index (FCI) algorithm was developed to take the multiplicative product of the red and near infrared bands and apply a threshold to separate tree cover from non-tree cover in multispectral imagery (MSI). Previous testing focused on one study site using 2-m resolution commercial MSI from WorldView-2 and 30-m resolution imagery from Landsat-7. New testing in this work used 3-m imagery from PlanetScope and 10-m imagery from Sentinel-2 in imagery in sites across 12 biomes in South and Central America and North Korea. Overall accuracy ranged between 23% and 97% for Sentinel-2 imagery and between 51% and 98% for PlanetScope imagery. Future research will focus on automating the identification of the threshold that separates tree from other land covers, exploring use of the output for machine learning applications, and incorporating ancillary data such as digital surface models and existing tree cover maps.
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Manninen, Terhikki, and Pauline Stenberg. Influence of forest floor vegetation on the total forest reflectance and its implications for LAI estimation using vegetation indices. Finnish Meteorological Institute, 2021. http://dx.doi.org/10.35614/isbn.9789523361379.

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Recently a simple analytic canopy bidirectional reflectance factor (BRF) model based on the spectral invariants theory was presented. The model takes into account that the recollision probability in the forest canopy is different for the first scattering than the later ones. Here this model is extended to include the forest floor contribution to the total forest BRF. The effect of the understory vegetation on the total forest BRF as well as on the simple ratio (SR) and the normalized difference (NDVI) vegetation indices is demonstrated for typical cases of boreal forest. The relative contribution of the forest floor to the total BRF was up to 69 % in the red wavelength range and up to 54 % in the NIR wavelength range. Values of SR and NDVI for the forest and the canopy differed within 10 % and 30 % in red and within 1 % and 10 % in the NIR wavelength range. The relative variation of the BRF with the azimuth and view zenith angles was not very sensitive to the forest floor vegetation. Hence, linear correlation of the modelled total BRF and the Ross-thick kernel was strong for dense forests (R2 > 0.9). The agreement between modelled BRF and satellite-based reflectance values was good when measured LAI, clumping index and leaf single scattering albedo values for a boreal forest were used as input to the model.
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Busby, Ryan, Dick Gebhart, Steven Oxley, William Tarantino, and Wade Wall. Estimating resistance and resilience of military lands using vegetation indices. Construction Engineering Research Laboratory (U.S.), September 2017. http://dx.doi.org/10.21079/11681/23953.

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4

Cole, David N. Area of vegetation loss: a new index of campsite impact. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station, 1989. http://dx.doi.org/10.2737/int-rn-389.

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5

Chen, J. M. Evaluation of vegetation indices and a Modified Simple Ratio for boreal applications. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/218303.

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6

Kamenova, Ilina, Lachezar Filchev, and Iliana Ilieva. Review of spectral vegetation indices and methods for estimation of crop biophysical variables. Prof. Marin Drinov Publishing House of Bulgarian Academy of Sciences, April 2018. http://dx.doi.org/10.7546/aerebu.29.18.01.06.

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7

Rochdi, N., and R. Fernandes. Intercalibration of vegetation indices from Landsat ETM+ and MODIS 500m data for LAI mapping. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2008. http://dx.doi.org/10.4095/226024.

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8

Pradhan, Nawa Raj. Estimating growing-season root zone soil moisture from vegetation index-based evapotranspiration fraction and soil properties in the Northwest Mountain region, USA. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42128.

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A soil moisture retrieval method is proposed, in the absence of ground-based auxiliary measurements, by deriving the soil moisture content relationship from the satellite vegetation index-based evapotranspiration fraction and soil moisture physical properties of a soil type. A temperature–vegetation dryness index threshold value is also proposed to identify water bodies and underlying saturated areas. Verification of the retrieved growing season soil moisture was performed by comparative analysis of soil moisture obtained by observed conventional in situ point measurements at the 239-km2 Reynolds Creek Experimental Watershed, Idaho, USA (2006–2009), and at the US Climate Reference Network (USCRN) soil moisture measurement sites in Sundance, Wyoming (2012–2015), and Lewistown, Montana (2014–2015). The proposed method best represented the effective root zone soil moisture condition, at a depth between 50 and 100 cm, with an overall average R2 value of 0.72 and average root mean square error (RMSE) of 0.042.
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Salazar, Lina, Ana Claudia Palacios, Michael Selvaraj, and Frank Montenegro. Using Satellite Images to Measure Crop Productivity: Long-Term Impact Assessment of a Randomized Technology Adoption Program in the Dominican Republic. Inter-American Development Bank, September 2021. http://dx.doi.org/10.18235/0003604.

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This study combines three rounds of surveys with remote sensing to measure long-term impacts of a randomized irrigation program in the Dominican Republic. Specifically, Landsat 7 and Landsat 8 satellite images are used to measure the causal effects of the program on agricultural productivity, measured through vegetation indices (NDVI and OSAVI). To this end, 377 plots were analyzed (129 treated and 248 controls) for the period from 2011 to 2019. Following a Differencein-Differences (DD) and Event study methodology, the results confirmed that program beneficiaries have higher vegetation indices, and therefore experienced a higher productivity throughout the post-treatment period. Also, there is some evidence of spillover effects to neighboring farmers. Furthermore, the Event Study model shows that productivity impacts are obtained in the third year after the adoption takes place. These findings suggest that adoption of irrigation technologies can be a long and complex process that requires time to generate productivity impacts. In a more general sense, this study reveals the great potential that exists in combining field data with remote sensing information to assess long-term impacts of agricultural programs on agricultural productivity.
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Broussard, Whitney, Glenn Suir, and Jenneke Visser. Unmanned Aircraft Systems (UAS) and satellite imagery collections in a coastal intermediate marsh to determine the land-water interface, vegetation types, and Normalized Difference Vegetation Index (NDVI) values. Engineer Research and Development Center (U.S.), October 2018. http://dx.doi.org/10.21079/11681/29517.

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