907 resultados para Natural resources -- Remote sensing
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Slope instabilities – commonly triggered by rainfall – pose a geotechnical risk causing disruption to transport routes and incur significant financial resources. This article details laboratory, ground and remote sensing investigations carried out by Queen’s University Belfast and Transport Northern Ireland (TNI) to characterise and monitor slope instability on two higher risk infrastructure slopes in Northern Ireland. The research is used to update a noninvasive risk assessment model of slopes across the country’s road network to direct resources for future investigation.
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Os biocombustíveis têm estado na linha da frente das políticas energéticas mundiais visto que as suas vantagens conseguem colmatar as incertezas e resolver alguns dos problemas associados aos combustíveis fósseis. O biodiesel tem provado ser um combustível muito fiável, alternativo ao petrodiesel. É uma mistura de ésteres alquílicos produzidos a partir de óleos vegetais e gorduras animais através de uma reacção de transesterificação. Como combustível, o biodiesel é economicamente viável, socialmente responsável, tecnicamente compatível e ambientalmente amigável. O principal desafio associado ao seu desenvolvimento tem a ver com a escolha de matéria-prima para a sua produção. Nos países do terceiro mundo, óleos alimentares são mais importantes para alimentar pessoas do que fazer funcionar carros. Esta tese tem como objectivos produzir/processar biodiesel a partir de recursos endógenos de Timor-Leste e medir/prever as propriedades termodinâmicas do biodiesel, a partir das dos esteres alquílicos. A síntese do biodiesel a partir dos óleos de Aleurites moluccana, Jatropha curcas e borras de café foram aqui estudados. As propriedades termodinâmicas como densidade, viscosidade, tensão superficial, volatilidade e velocidade do som também foram medidas e estimadas usando modelos preditivos disponíveis na literatura, incluindo as equações de estado CPA e soft-SAFT. Timor-Leste é um país muito rico em recursos naturais, mas a maioria da população ainda vive na pobreza e na privação de acesso a serviços básicos e condições de vida decentes. A exploração de petróleo e gás no mar de Timor tem sido controlado pelo Fundo Petrolífero. O país ainda carece de electricidade e combustíveis que são cruciais para materializar as políticas de redução da pobreza. Como solução, o governo timorense criou recentemente o Plano Estratégico de Desenvolvimento a 20 anos cujas prioridades incluem trazer o desenvolvimento do petróleo do mar para a costa sul de Timor-Leste e desenvolver as energias renováveis. É neste último contexto que o biodiesel se insere. O seu desenvolvimento no país poderá ser uma solução para o fornecimento de electricidade, a criação de empregos e sobretudo o combate contra a pobreza e a privação. Para ser usado como combustível, no entanto, o biodiesel deve possuir propriedades termodinâmicas coerentes com as especificadas nas normas da ASTM D6751 (nos Estados Unidos) ou EN 14214 (na Europa) para garantir uma adequada ignição, atomização e combustão do biodiesel no motor.
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Intensive use of Distributed Generation (DG) represents a change in the paradigm of power systems operation making small-scale energy generation and storage decision making relevant for the whole system. This paradigm led to the concept of smart grid for which an efficient management, both in technical and economic terms, should be assured. This paper presents a new approach to solve the economic dispatch in smart grids. The proposed methodology for resource management involves two stages. The first one considers fuzzy set theory to define the natural resources range forecast as well as the load forecast. The second stage uses heuristic optimization to determine the economic dispatch considering the generation forecast, storage management and demand response
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The global dynamics of alliances are strongly determined by the level of cooperation among states. This cooperation can be embodied in various aspects, but the level of defense and security cooperation becomes usually more doctrinal and lasting. By the nature of sovereignty that instills in the bilateral relationship, cooperation at defense and security level can leverages other forms of cooperation. The circumstances and relational balance between Brazil and Portugal seem to evolve towards distancing opportunities, despite they are culturally and institutionally untainted. The economic dynamics, the strategic projection in global sustainability terms, the scale and ambition of Brazilian regional leadership, contrasts with the actual context of Portugal, distancing himself both on the stage where they operate. On the other hand, the historical and cultural roots, the language, the affinity of the peoples of CPLP and some opportunities for economic niches, trend to attract both countries. The condition of Portugal in NATO and Europe, coupled with the ability to export technical and human resources to value-added for Brazil, seems also to become approaching factors. On the balance of these dynamics, there is a set of exogenous factors (economic, external global relations matrix, regional stability, among others), which are not always controlled by any of both countries. These factors call for strong capacity for foresight analysis and decision making, with the inherent risk. There is cooperation vectors that are not apparently penalized by geographic distance, or by the difference of realities. Among these vectors we shall highlight synergies in technological niches, highly tradable goods and, mostly, using the domain of dual technologies. The thirteen niches herein identified are: Monitoring, Navigation, Command and Control, Electronics, Optoelectronics, Communication and remote sensing, Information Technologies, Flight Simulation, Specialized Training, Fiber Optic Sensors, Materials Engineering, Nanotechnology and Communications. Cumulating with identified opportunities in traditional relational framework, both countries are growing (in geography and economic terms) into the Atlantic, making it a central element in the bilateral approach. By being at the same time a growing stage of disputes and which stability tends to be threatened, it will be done an analysis of these synergistic vectors, superimposed on the impact on Atlantic securitization process.
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Grasslands in semi-arid regions, like Mongolian steppes, are facing desertification and degradation processes, due to climate change. Mongolia’s main economic activity consists on an extensive livestock production and, therefore, it is a concerning matter for the decision makers. Remote sensing and Geographic Information Systems provide the tools for advanced ecosystem management and have been widely used for monitoring and management of pasture resources. This study investigates which is the higher thematic detail that is possible to achieve through remote sensing, to map the steppe vegetation, using medium resolution earth observation imagery in three districts (soums) of Mongolia: Dzag, Buutsagaan and Khureemaral. After considering different thematic levels of detail for classifying the steppe vegetation, the existent pasture types within the steppe were chosen to be mapped. In order to investigate which combination of data sets yields the best results and which classification algorithm is more suitable for incorporating these data sets, a comparison between different classification methods were tested for the study area. Sixteen classifications were performed using different combinations of estimators, Landsat-8 (spectral bands and Landsat-8 NDVI-derived) and geophysical data (elevation, mean annual precipitation and mean annual temperature) using two classification algorithms, maximum likelihood and decision tree. Results showed that the best performing model was the one that incorporated Landsat-8 bands with mean annual precipitation and mean annual temperature (Model 13), using the decision tree. For maximum likelihood, the model that incorporated Landsat-8 bands with mean annual precipitation (Model 5) and the one that incorporated Landsat-8 bands with mean annual precipitation and mean annual temperature (Model 13), achieved the higher accuracies for this algorithm. The decision tree models consistently outperformed the maximum likelihood ones.
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Vineyards vary over space and time, making geomatics technologies ideally suited to study terroir. This study applied geomatics technologies - GPS, remote sensing and GIS - to characterize the spatial variability at Stratus Vineyards in the Niagara Region. The concept of spatial terroir was used to visualize, monitor and analyze the spatial and temporal variability of variables that influence grape quality. Spatial interpolation and spatial autocorrelation were used to measure the pattern demonstrated by soil moisture, leaf water potential, vine vigour, soil composition and grape composition on two Cabernet Franc blocks and one Chardonnay block. All variables demonstrated some spatial variability within and between the vineyard block and over time. Soil moisture exhibited the most significant spatial clustering and was temporally stable. Geomatics technologies provided valuable spatial information related to the natural spatial variability at Stratus Vineyards and can be used to inform and influence vineyard management decisions.
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This paper proposes a model of natural-resource exploitation when private ownership requires costly enforcement activities. For a given wage rate, it is shown how enforcement costs can increase with labor's average productivity on a resource site. As a result, it is never optimal for the site owner to produce at the point where marginal productivity equals the wage rate. It may even be optimal to exploit at a point exhibiting negative marginal returns. An important parameter in the analysis is the prevailing wage rate. When wages are low, further decreases in the wage rates can reduce the returns from resource exploitation. At sufficiently low wages, positive returns can be rendered impossible to achieve and the site is abandoned to a free-access exploitation. The analysis provides some clues as to why property rights may be more difficult to delineate in less developed countries. It proposes a different framework from which to address normative issues such as the desirability of free trade with endogenous enforcement costs, the optimality of private decisions to enforce property rights, the effect of income distribution on property rights enforceability, etc.
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We analyze the behavior of a nonrenewable resource cartel that anticipates being forced, at some date in the future, to break-up into an oligopolistic market in which its members will then have to compete as rivals. Under reasonable assumptions about the value function of the individual firms in the oligopolistic equilibrium that follows the break-up, we show that the cartel will then produce more over the same interval of time than it would if there were no threat of dissolution, and that its rate of extraction is a decreasing function of the cartel's life; that there are circumstances under which the cartel will attach a negative marginal value to the resource stocks, in which case the rate of depletion will be increasing over time during the cartel phase; that, for a given date of dissolution, the equilibrium stocks allocated to the post-cartel phase will increase as a function of the total initial stocks, whereas those allocated to the cartel phase will increase at first, but begin decreasing beyond some level of the total initial stocks.
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We derive conditions that must be satisfied by the primitives of the problem in order for an equilibrium in linear Markov strategies to exist in some common property natural resource differential games. These conditions impose restrictions on the admissible form of the natural growth function, given a benefit function, or on the admissible form of the benefit function, given a natural growth function.
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Ce travail s’inscrit dans le cadre d’un programme de recherches appuyé par le Conseil de recherches en sciences humaines du Canada.
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L’érosion éolienne est un problème environnemental parmi les plus sévères dans les régions arides, semi-arides et les régions sèches sub-humides de la planète. L’érosion des sols accélérée par le vent provoque des dommages à la fois localement et régionalement. Sur le plan local, elle cause la baisse des nutriments par la mobilisation des particules les plus fines et de la matière organique. Cette mobilisation est une des causes de perte de fertilité des sols avec comme conséquence, une chute de la productivité agricole et une réduction de la profondeur de la partie arable. Sur le plan régional, les tempêtes de poussières soulevées par le vent ont un impact non négligeable sur la santé des populations, et la déposition des particules affecte les équipements hydrauliques tels que les canaux à ciel ouvert ainsi que les infrastructures notamment de transport. Dans les régions où les sols sont fréquemment soumis à l’érosion éolienne, les besoins pour des études qui visent à caractériser spatialement les sols selon leur degré de vulnérabilité sont grands. On n’a qu’à penser aux autorités administratives qui doivent décider des mesures à prendre pour préserver et conserver les potentialités agropédologiques des sols, souvent avec des ressources financières modestes mises à leur disposition. Or, dans certaines de ces régions, comme notre territoire d’étude, la région de Thiès au Sénégal, ces études font défaut. En effet, les quelques études effectuées dans cette région ou dans des contextes géographiques similaires ont un caractère plutôt local et les approches suivies (modèles de pertes des sols) nécessitent un nombre substantiel de données pour saisir la variabilité spatiale de la dynamique des facteurs qui interviennent dans le processus de l’érosion éolienne. La disponibilité de ces données est particulièrement problématique dans les pays en voie de développement, à cause de la pauvreté en infrastructures et des problèmes de ressources pour le monitoring continu des variables environnementales. L’approche mise de l’avant dans cette recherche vise à combler cette lacune en recourant principalement à l’imagerie satellitale, et plus particulièrement celle provenant des satellites Landsat-5 et Landsat-7. Les images Landsat couvrent la presque totalité de la zone optique du spectre exploitable par télédétection (visible, proche infrarouge, infrarouge moyen et thermique) à des résolutions relativement fines (quelques dizaines de mètres). Elles permettant ainsi d’étudier la distribution spatiale des niveaux de vulnérabilité des sols avec un niveau de détails beaucoup plus fin que celui obtenu avec des images souvent utilisées dans des études environnementales telles que AVHRR de la série de satellites NOAA (résolution kilométrique). De plus, l’archive complet des images Landsat-5 et Landsat-7 couvrant une période de plus de 20 ans est aujourd’hui facilement accessible. Parmi les paramètres utilisés dans les modèles d’érosion éolienne, nous avons identifiés ceux qui sont estimables par l’imagerie satellitale soit directement (exemple, fraction du couvert végétal) soit indirectement (exemple, caractérisation des sols par leur niveau d’érodabilité). En exploitant aussi le peu de données disponibles dans la région (données climatiques, carte morphopédologique) nous avons élaboré une base de données décrivant l’état des lieux dans la période de 1988 à 2002 et ce, selon les deux saisons caractéristiques de la région : la saison des pluies et la saison sèche. Ces données par date d’acquisition des images Landsat utilisées ont été considérées comme des intrants (critères) dans un modèle empirique que nous avons élaboré en modulant l’impact de chacun des critères (poids et scores). À l’aide de ce modèle, nous avons créé des cartes montrant les degrés de vulnérabilité dans la région à l’étude, et ce par date d’acquisition des images Landsat. Suite à une série de tests pour valider la cohérence interne du modèle, nous avons analysé nos cartes afin de conclure sur la dynamique du processus pendant la période d’étude. Nos principales conclusions sont les suivantes : 1) le modèle élaboré montre une bonne cohérence interne et est sensible aux variations spatiotemporelles des facteurs pris en considération 2); tel qu’attendu, parmi les facteurs utilisés pour expliquer la vulnérabilité des sols, la végétation vivante et l’érodabilité sont les plus importants ; 3) ces deux facteurs présentent une variation importante intra et inter-saisonnière de sorte qu’il est difficile de dégager des tendances à long terme bien que certaines parties du territoire (Nord et Est) aient des indices de vulnérabilité forts, peu importe la saison ; 4) l’analyse diachronique des cartes des indices de vulnérabilité confirme le caractère saisonnier des niveaux de vulnérabilité dans la mesure où les superficies occupées par les faibles niveaux de vulnérabilité augmentent en saison des pluies, donc lorsque l’humidité surfacique et la végétation active notamment sont importantes, et décroissent en saison sèche ; 5) la susceptibilité, c’est-à-dire l’impact du vent sur la vulnérabilité est d’autant plus forte que la vitesse du vent est élevée et que la vulnérabilité est forte. Sur les zones où la vulnérabilité est faible, les vitesses de vent élevées ont moins d’impact. Dans notre étude, nous avons aussi inclus une analyse comparative entre les facteurs extraits des images Landsat et celles des images hyperspectrales du satellite expérimental HYPERION. Bien que la résolution spatiale de ces images soit similaire à celle de Landsat, les résultats obtenus à partir des images HYPERION révèlent un niveau de détail supérieur grâce à la résolution spectrale de ce capteur permettant de mieux choisir les bandes spectrales qui réagissent le plus avec le facteur étudié. Cette étude comparative démontre que dans un futur rapproché, l’amélioration de l’accessibilité à ce type d’images permettra de raffiner davantage le calcul de l’indice de vulnérabilité par notre modèle. En attendant cette possibilité, on peut de contenter de l’imagerie Landsat qui offre un support d’informations permettant tout de même d’évaluer le niveau de fragilisation des sols par l’action du vent et par la dynamique des caractéristiques des facteurs telles que la couverture végétale aussi bien vivante que sénescente.
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The present investigation on the Muvattupuzha river basin is an integrated approach based on hydrogeological, geophysical, hydrogeochemical parameters and the results are interpreted using satellite data. GIS also been used to combine the various spatial and non-spatial data. The salient finding of the present study are accounted below to provide a holistic picture on the groundwaters of the Muvattupuzha river basin. In the Muvattupuzha river basin the groundwaters are drawn from the weathered and fractured zones. The groundwater level fluctuations of the basin from 1992 to 2001 reveal that the water level varies between a minimum of 0.003 m and a maximum of 3.45 m. The groundwater fluctuation is affected by rainfall. Various aquifer parameters like transmissivity, storage coefficient, optimum yield, time for full recovery and specific capacity indices are analyzed. The depth to the bedrock of the basin varies widely from 1.5 to 17 mbgl. A ground water prospective map of phreatic aquifer has been prepared based on thickness of the weathered zone and low resistivity values (<500 ohm-m) and accordingly the basin is classified in three phreatic potential zones as good, moderate and poor. The groundwater of the Muvattupuzha river basin, the pH value ranges from 5.5 to 8.1, in acidic nature. Hydrochemical facies diagram reveals that most of the samples in both the seasons fall in mixing and dissolution facies and a few in static and dynamic natures. Further study is needed on impact of dykes on the occurrence and movement of groundwater, impact of seapages from irrigation canals on the groundwater quality and resources of this basin, and influence of inter-basin transfer of surface water on groundwater.
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This doctoral thesis addresses the growing concern about the significant changes in the climatic and weather patterns due to the aerosol loading that have taken place in the Indo Gangetic Plain(IGP)which includes most of the Northern Indian region. The study region comprises of major industrial cities in India (New Delhi, Kanpur, Allahabad, Jamshedpur and Kolkata). Northern and central parts of India are one of the most thickly populated areas in the world and have the most intensely farmed areas. Rapid increase in population and urbanization has resulted in an abrupt increase in aerosol concentrations in recent years. The IGP has a major source of coal; therefore most of the industries including numerous thermal power plants that run on coal are located around this region. They inject copious amount of aerosols into the atmosphere. Moreover, the transport of dust aerosols from arid locations is prevalent during the dry months which increase the aerosol loading in theatmosphere. The topography of the place is also ideal for the congregation of aerosols. It is bounded by the Himalayas in the north, Thar Desert in the west, the Vindhyan range in the south and Brahmaputra ridge in the east. During the non‐monsoon months (October to May) the weather in the location is dry with very little rainfall. Surface winds are weak during most of the time in this dry season. The aerosols that reach the location by means of long distance transport and from regional sources get accumulated under these favourable conditions. The increase in aerosol concentration due to the complex combination of aerosol transport and anthropogenic factors mixed with the contribution from the natural sources alters the optical properties and the life time of clouds in the region. The associated perturbations in radiative balance have a significant impact on the meteorological parameters and this in turn determines the precipitation forming process. Therefore, any change in weather which disturbs the normal hydrological pattern is alarming in the socio‐economic point of view. Hence, the main focus of this work is to determine the variation in transport and distribution of aerosols in the region and to understand the interaction of these aerosols with meteorological parameters and cloud properties.
Continuation and discontinuation of local institution in community based natural resource management
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Currently the push toward frontier areas, which until twenty years ago were still largely untouched by commercial agriculture, is taking place on a massive scale. This push is being driven not the least by global economic developments, such as the price increase of agriculture commodities like coffee and cocoa. In most cases the indigenous communities become trapped between the state monopoly in natural resource management and the competition for resources by external actors. In this processes the indigenous communities start to lose their access to resources. Another victim in this process is the environment where the natural resources are imbedded. International and national organizations working to conserve environment have became conscious of the important role that indigenous people could fulfill as partners in this endeavour. This partnership in struggle has produced a new discourse on the relationship between indigenous people and their environment. As a further consequence, programs were set up to develop what became known as Community Based Natural Resource Management (CBNRM) with its numerous variations. Based on a case study in a village on the eastern border of the Lore Lindu National Park in Central Sulawesi, this study questioned the basic assumption behind the concept of Community Based Natural Resource Management (CBNRM). Namely the assumption that communities living at the margin of forest are socially and culturally homogenous, still more or less egalitarian, and basically living in harmony with their natural environment. This study was inspired by the persistent critique – although still a minority – on the basic assumption the CBNRM from academicians and practitioners working through the Entitlement perspective. Another inspiration was the mounting critique toward the participatory approach. In its effort the study explore further the usefulness of certain approaches. One of the approach much relied on in this study was the local history of the community studied, through exerting oral and local written documents on local history, legends and local stories. These sources proofed quite capable in bringing the local history into the light. Another was the actor oriented approach, which later came to be supported by the concept of Social Pool Resources. The latter concept proofed to be useful as analytical instrument to integrate social institutions and the common pool resources, as a field of action for the different actors as human agencies.
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The indigenous vegetation surrounding the river oases on the southern rim of the Taklamakan Desert has drastically diminished due to overexploitation as a source of fodder, timber and fuel for the human population. The change in the spatial extent of landscape forms and vegetation types around the Qira oasis was analyzed by comparing SPOT satellite images from 1998 with aerial photographs from 1956. The analysis was supplemented by field surveys in 1999 and 2000. The study is part of a joint Chinese-European project with the aim of assessing the current state of the foreland vegetation, of gathering information on the regeneration potential and of suggesting procedures for a sustainable management. With 33 mm of annual precipitation, plants can only grow if they have access to groundwater, lakes or rivers. Most of the available water comes into the desert via rivers in the form of seasonal flooding events resulting from snow melt in the Kun Lun Mountains. This water is captured in canal systems and used for irrigation of arable fields. Among the eight herbaceous and woody vegetation types and the type of open sand without any plant life that were mapped in 2000 in the oasis foreland, only the latter, the oasis border between cultivated land and open Populus euphratica forests and Tamarix ramosissima-Phragmites australis riverbed vegetation could be clearly identified on the photographs from 1956. The comparison of the images revealed that the oasis increased in area between 1956 and 2000. Shifting sand was successfully combated near to the oasis borders but increased in extent at the outward border of the foreland vegetation. In contrast to expectations, the area covered with Populus trees was smaller in 1956 than today due to some new forests in the north of the oasis that have grown up since 1977. Subfossil wood and leaf remnants of Populus euphratica that were found in many places in the foreland must have originated from forests destroyed before 1956. In the last 50 years, the main Qira River has shifted its bed significantly northward and developed a new furcation with a large new bed in 1986. The natural river dynamics are not only an important factor in forming the oasis’ landscape but also in providing the only possible regeneration sites for all occurring plant species. The conclusion of the study is that the oasis landscape has changed considerably in the last 50 years due to natural floodings and to vegetation degradation by human overexploitation. The trend towards decreasing width of the indigenous vegetation belt resulting from the advancing desert and the expansion of arable land is particularly alarming because a decrease in its protective function against shifting sand can be expected in the future.