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Impatto e prevenzione dell'inquinamento delle acque sotterranee da pesticidi e nitrati nei vigneti collinari: valutazione delle fonti di contaminazione e sviluppo delle migliori pratiche di gestione e misure di mitigazione / IMPACT AND PREVENTION OF GROUNDWATER POLLUTION BY PESTICIDES AND NITRATE IN HILLY VINEYARDS: EVALUATION OF CONTAMINATION SOURCES AND DEVELOPMENT OF BEST MANAGEMENT PRACTICES AND MITIGATION MEASURES / Impact and prevention of groundwater pollution by pesticides and nitrate in hilly vineyards: evaluation of contamination sources and development of best management practices and mitigation measuresZAMBITO MARSALA, ROBERTA 28 April 2021 (has links)
Molte attività antropiche danno origine a problemi ambientali per i quali è necessario trovare soluzioni. La presenza di sostanze indesiderabili nell'acqua, infatti, può rappresentare un rischio per la salute e l'igiene sia degli uomini che degli animali. È quindi fondamentale trovare metodi per evitare gli inquinanti di queste matrici, in modo da renderli compatibili con il mantenimento di condizioni ambientali adeguate e salutari.
Questa tesi si propone di valutare la qualità delle acque sotterranee di un'area in cui la qualità dell'acqua non è mai stata studiata, in particolare indagando la presenza di pesticidi e nitrati al fine di comprendere l’impatto della viticoltura sull'inquinamento delle acque sotterranee. Questo studio nasce dalla necessità di migliorare la governance delle acque e di implementare le migliori pratiche di gestione e misure di mitigazione per prevenire l'inquinamento delle acque e quello ambientale.
I risultati degli studi di monitoraggio hanno mostrato una contaminazione delle acque sotterranee da parte di pesticidi e nitrati e quindi è stata effettuata una valutazione della fonte di contaminazione da pesticidi e nitrati attraverso studi isotopici di N e O di NO3-, e attraverso analisi idrologiche utilizzando il modello CRITERIA 3D.
Come una delle principali conclusioni del lavoro si può affermare che la presenza di pesticidi nelle acque sotterranee in un’area ad attività vitivinicola intensa, non può essere correlata solo alle proprietà e al destino chimico-ambientale delle sostanze o alle condizioni pedoclimatiche, ma anche al comportamento dell'utilizzatore finale. In effetti, la fonte di contaminazione valutata, è risultata essere dovuta sia a una contaminazione diffusa che a una contaminazione puntiforme.
Per quanto riguarda l'influenza della fertilizzazione a base di azoto sulla presenza di nitrati nelle acque sotterranee, i risultati hanno mostrato un'elevata vulnerabilità dell'acquifero ai cambiamenti esterni. Dalle indagini isotopiche è emerso che la maggior parte dell'NO3- rilevato nelle acque sotterranee, deriva dall'utilizzo di fertilizzanti azotati inorganici, in accordo con le pratiche di uso del suolo e di viticoltura dichiarate dagli agricoltori della zona.
Il risultato più importante dello studio, tuttavia, è stato che alla fine del processo, l'approccio multi-actor e la strategia di coinvolgimento adottati, hanno avuto successo nel migliorare gli atteggiamenti verso pratiche più sostenibili. / Many anthropic activities give rise to environmental problems for which it is necessary to find solutions. The presence of undesirable substances in water, indeed, can pose a risk to the health and hygiene of both men and animals. It is, therefore, essential to find methods in order to avoid pollutants from these matrices, so as to make them compatible with the maintenance of healthy environmental conditions.
This thesis aims to assessing the groundwater quality of an area in which the quality of water was never studied, particularly investigating the occurrence of pesticides and nitrate in order to understand the grant of viticulture on water pollution. This study derives from the necessity to improve the water governance and to implement the best management practices and mitigation measures to prevent groundwater and environmental pollution.
The results of monitoring studies showed a contamination of groundwater by pesticides and nitrate and thus an evaluation of PPPs and nitrates source contamination was carried out through isotopic studies of N and O of NO3- , and through hydrologic analysis by use of the model CRITERIA 3D.
As one of the main conclusions of the work, the occurrence of PPPs in groundwater in areas with intensive viticultural activities cannot be related just to chemical environmental fate properties or pedoclimatic conditions, but also to end-user behavior. In fact, the contamination source evaluated, resulted to be due to both diffuse and point-source contamination.
For what concerns the influence of nitrogen-based fertilization on nitrate occurrence in groundwater, the results showed a high vulnerability of the aquifer to external changes. Isotopic investigations showed that most of the NO3- detected in the groundwater, derived from the use of inorganic nitrogen fertilizers, in agreement with the land use and viticulture practices declared by the farmers.
The most important result of the study, however, was that at the end of the overall process, the multi-actor approach and engagement strategy adopted were successful in improving attitudes to more sustainable practices.
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[en] AFTER COFFEE RUNS OUT: BIOGEOGRAPHY AND ENVIRONMENTAL HISTORY OF FOREST REMNANTS IN THE PARAÍBA DO SUL RIVER VALLEY (RJ E SP) / [pt] DEPOIS QUE O CAFÉ ACABOU: BIOGEOGRAFIA E HISTÓRIA AMBIENTAL DE REMANESCENTES FLORESTAIS DO VALE DO RIO PARAÍBA DO SUL (RJ E SP)GILSON ROBERTO DE SOUZA 17 January 2022 (has links)
[pt] Do ponto de vista histórico, a cafeicultura teve um papel relevante sobre a composição e estrutura das florestas no domínio da Mata Atlântica, especialmente no século XIX em todo o Vale do Rio Paraíba do Sul, localizado na interceção dos estados de SP, RJ e MG. Esta atividade gerou uma paisagem composta por mosaicos florestais que foram definidos por diferentes sobreposições de usos, em distintas escalas temporais. Seu legado deixou marcas na paisagem e muitas estão ocultas sob estes mosaicos vegetacionais, sendo revelados a partir do estudo de sua flora e vegetação. Este trabalho teve como objetivo avaliar a composição florística e a estrutura do estrato arbustivo e arbóreo de fragmentos de Mata Atlântica no Vale do Paraíba RJ/SP, com diferentes estágios sucessionais e distintas sobreposições de usos após o ciclo do café. Foi analisada a estrutura floristica e fitossociológica de oito fragmentos que compartilham o mesmo histórico de uso. Em seguida, foram analisadas as marcas humanas nestas florestas através do inventário de espécies exóticas e vestígios físicos de diferentes contextos históricos. Por fim, foi feita uma análise do entorno de cada fragmento por imagens de satélite. A metologia utilizada consistiu: 1) no levantamento fitossociológico em 20 parcelas de 10 x 10 m2 contíguas, perfazendo 0,2 ha em cada fragmento; 2) análise granulométrica e de fertilidade do solo nas profundidades de 0-10 e 10-20 cm; 3) levantamento de espécies exóticas nas florestas; 4) registros de macrovestígios de usos pretéritos nos fragmentos e 5) utilização e interpretação de imagens de satélite para cada fragmento estudado. Os resultados indicam que os fragmentos estudados contemporâneos à época do café. Muito possivelmente são de áreas onde onde anteriomente existiam cafezais e, com o declinio deste, deu-se o processo de sucessão ecológica, representando hoje esta paisagem uma convergência de histórias naturais e humanas. As investigações acerca da paisagem que circunda os fragmentos dimensiona as semelhanças que há entre eles, pois estão dentro de uma mesma matriz e contexto histórico. A interpretação destes eventos temporais sobre os aspectos das florestas a partir do legado do café por diferentes sobreposições de uso contribui para compreensão das dimensões biogeográficas e da história ambiental da sua paisagem. Neste contexto, o entendimento dos usos antrópicos pretéritos e a situação atual das florestas face ao aspecto cumulativo de usos contribui para a conservação destas florestas e dos valores ecológicos e culturais a elas associados. / [en] From a historical point of view, the heyday of coffee growing played a relevant role in the composition and structure of forests in the Atlantic Forest domain, especially in the 19th century throughout the Paraíba do Sul River Valley, located at the intersection of the states of SP, RJ, and MG. This activity generated a landscape composed of forest mosaics defined by overlapping uses at different time scales. His legacy left marks on the landscape, and many are hidden under these vegetation mosaics, revealed through the study of its flora and vegetation. This work aimed to evaluate the floristic composition and structure of the shrub and arboreal layer of Atlantic Forest fragments in the Paraíba Valley RJ/SP, with different successional stages and distinctions overlapping uses after the coffee cycle. The floristic and phytosociological structure of eight fragments that share the same history of use was analyzed. Then, the human marks in these forests were analyzed by inventory of exotic species and physical remains from different historical contexts. Finally, an analysis of the surroundings of each fragment was carried out using satellite images. The methodology used consisted of 1) a phytosociological survey with 20 contiguous plots of 10 x 10 m2, totaling 0.2 ha in each fragment; 2) granulometric and soil fertility analysis at depths of 0-10 and 10-20 cm; 3) survey of exotic species in forests; 4) records of a macro trace of past uses in the fragments and 5) use and interpretation of satellite images for each studied component. The results indicate that the studied fragments are not contemporary remnants of the coffee period. Quite possibly, they were from areas where coffee plantations previously existed and, with its decline, the process of ecological succession took place. Today, this landscape represents a convergence of natural and human histories. The investigations about the landscape surrounding the fragments scale the similarities between them, as they are within the same matrix and historical context. The interpretation of these temporal events on the aspects of forests from the coffee legacy through different use overlaps contributes to understanding the biogeographic dimensions and the environmental history of its landscape. In this context, understanding past anthropic uses and the current situation of forests in the face of the cumulative aspect of benefits contributes to the conservation of these forests and the ecological and cultural values associated with them.
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Liens entre l'hyperpigmentation chez des poissons récifaux et la maladie de la perte de tissu des coraux en GrenadeRubin, Bastien 12 1900 (has links)
Les coraux durs font face à des menaces croissantes dues à des facteurs anthropogéniques, les rendant vulnérables à des maladies telles que la maladie de perte de tissu des coraux (MPTC). Découverte en Floride en 2014, la MPTC s'est propagée dans la mer des Caraïbes et a atteint la Grenade en 2018, menaçant les récifs locaux. La relation complexe entre les facteurs environnementaux et la susceptibilité des coraux reste mal comprise. De plus, une hyperpigmentation cutanée a été observée chez divers poissons récifaux en Grenade, avec des causes et liens environnementaux inexplorés. Notre étude explore les corrélations potentielles entre la MPTC et l'hyperpigmentation chez la gorette jaune (Haemulon flavolineatum) et le chirurgien océanique (Acanthurus bahianus) sur 12 sites de plongée de la côte ouest de la Grenade. Nous examinons également les liens entre les scores de pression anthropique et la santé des coraux. Les résultats indiquent une prévalence de la MPTC de 45% à l'ouest de la Grenade en mai 2023, inférieure à celle observée en Floride. La baie de Saint-Georges, soumise à une pression anthropique élevée, montre un taux de mortalité moyen des coraux de 11%, dépassant significativement les sites à faible pression anthropique (P=0,020). De plus, la prévalence des poissons hyperpigmentés est corrélée significativement à celle de la MPTC chez les coraux (P=0.004), et le score de pression anthropique est positivement corrélé aux pourcentages de coraux morts (P=0.001). Cette étude préliminaire pose les bases pour des investigations longitudinales futures, fournissant un aperçu crucial de la MPTC en Grenade. / Hard coral, as vital habitats for reefs organisms, are threatened by anthropogenic factors, making them more susceptible to diseases, including Stony Coral Tissue Loss Disease (SCTLD). First described in Florida in 2014, SCTLD has spread throughout the Caribbean Sea and has been observed in Grenada since 2018, threatening local reefs. The intricate relationship between local environmental factors and coral susceptibility remains poorly understood. Additionally, Grenada's reefs have witnessed skin hyperpigmentation in various fish species, whose etiology and connection to environmental factors remain unexplored. This study investigated potential correlations between SCTLD and hyperpigmentation in French grunt (Haemulon flavolineatum) and ocean surgeonfish (Acanthurus bahianus) across 12 popular dive sites. It also explored potential links between anthropic pressure scores and coral health. The findings revealed a 45% prevalence of SCTLD among hard coral colonies, lower than observed in Florida. Saint George's Bay, subjected to high anthropic pressure, experienced a significant 11% mean coral mortality rate, surpassing sites with minimal anthropic pressure (P=0.020). Furthermore, the prevalence of hyperpigmented fishes significantly correlated with SCTLD prevalence in coral (P=0.004), and anthropic pressure scores exhibited a positive relationship with dead coral percentages (P=0.001). This preliminary study provides crucial insights into SCTLD in Grenada, laying the groundwork for future longitudinal investigations.
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Anthropic sediments on the Scottish North Atlantic seaboard : nature, versatility and value of middenHamlet, Laura Elisabeth January 2014 (has links)
Traditionally archaeology has referred to the anthropic sediments accumulated around prehistoric settlements with the blanket term ‘midden’. This is now recognised as an inadequate term to describe the complex formation processes and functions represented in these sediments. This thesis reviewed the body of evidence accumulated over the past century of research into Neolithic and Bronze Age settlements on the islands of the Scottish North Atlantic seaboard and extrapolated the many occurrences of ‘midden’. Several contexts emerged for these sediments including interior floors, hearths, exterior occupational surfaces, dumped deposits, building construction materials and abandonment infill. In addition, ‘midden’ is described added to cultivated soils to form fertile anthrosols. The way in which prehistoric communities exploited this material for agriculture and construction has been described through geoarchaeological research which implied that to past communities ‘midden’ was a valuable resource. This led to the formation of a model based upon a human ecodynamics framework to hypothesise sediment formation pathways. Rescue excavation at the Links of Noltland, Westray provided an opportunity to conduct a holistic landscape and fine resolution based study of Neolithic and Bronze Age settlement to test this model. The research incorporated auger survey, archaeological and geoarchaeological excavation, thin section micromorphology and SEM EDX analyses. Sediments identified in literature review and recovered from the field site were described using this toolkit and set within a cultural and environmental context. Results demonstrate that anthropic materials were incorporated into all contexts examined. Discrete burning and maintenance activities were found to have taken place during the gradual accumulation of open-air anthropic sediments whilst incorporation of fuel residues and hearth waste into floors lead to the gradual formation of ‘living floors’ inside structures. An unexpected discovery was evidence of animal penning within late Neolithic/Early Bronze Age settlement and the in situ burning of stabling waste. Three types iv | P a g e of land management strategy which relied upon the input of anthropic sediments were evidenced and the range and extent of anthropic inclusions in the landscape recorded. Spatial interpolation of auger survey data utilised a new sub-surface modelling technique being developed by the British Geological Survey to explore soil stratigraphic relationships in 3D. SEM EDX analysis supported micromorphological analysis providing chemical data for discrete inclusions and assisting in the identification of herbivore dun ash and the Orcadian funerary product ‘cramp’. SEM EDX analysis was also applied to fine organo-mineral material for statistical testing of nutrient loadings across context groups. It was found that anthropic sediments were enriched in macro and intermediate plant nutrients Mg, P, K, S and Ca compared to geological controls, and the application of anthropic material to cultivated soils improved soil fertility for the three observed land management practices. The versatility of anthropic sediments was explored through discussion of context groups based upon the results of this research and the potential significance of this material to prehistoric communities is explored.
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Facteurs influençant les stratégies de recherche alimentaire des oiseaux marins : une approche comportementale / Factors affecting searching strategies of foraging seabirds : a behavioral approachCollet, Julien 18 October 2018 (has links)
Comprendre les décisions prises par les organismes pour s’approvisionner en nourriture est essentiel pour anticiper leurs réactions aux changements de l’environnement. Les oiseaux marins en reproduction partent s’alimenter en mer depuis leur colonie. L’utilisation de GPS miniatures révèle qu’ils effectuent des trajets de dizaines jusqu’à des milliers de kilomètres en quête de proies pour lesquelles nous disposons de très peu d’informations. Les stratégies comportementales qu’ils utilisent pour augmenter leurs chances de rencontrer des proies dans l’environnement marin, et les implications que cela peut avoir vis-à-vis des activités humaines de pêche qui semblent attirer de nombreux oiseaux sont encore très partiellement comprises. Cette thèse propose de réexaminer ces questions en trois chapitres, à travers des simulations théoriques, l’analyse empirique de trajets enregistrés par GPS sur diverses espèces et populations d’oiseaux marins, et le croisement des trajets simultanés d’oiseaux et de bateaux de pêche. Premièrement, les simulations théoriques de marches aléatoires montrent qu’on ne peut pas se servir des phases de ligne droite dans un trajet pour conclure si les oiseaux anticipent où sont leurs proies, ce qui vient nuancer les conclusions de nombreuses études précédentes. L’analyse des biais dans les directions suivies par les oiseaux permet en revanche de comprendre les informations qu’ils utilisent pour décider où s’approvisionner. Deuxièmement, les stratégies de fidélité spatiale individuelle sont comparées entre espèces, populations et contextes écologiques à l’aide de modèles statistiques multivariés (GLMM). De nombreux oiseaux marins font en effet preuve de fidélité individuelle dans la direction qu’ils prennent pour s’approvisionner depuis la colonie, suggérant l’utilisation de mémoire. Nous montrons que c’est également le cas de nombreuses populations et espèces d’oiseaux marins tropicaux, qui restent fidèles à une direction pendant plusieurs jours successifs. Ces résultats sont surprenants et difficiles à expliquer car la plupart des espèces étudiées ciblent des proies très dynamiques et disponibles à un endroit de façon très éphémère. Cela suggère que la mémoire pourrait être plus fréquemment utilisée par les oiseaux marins que ce que l’on supposait, au moins à large échelle spatiale. Finalement, nos analyses sur les réponses des albatros aux bateaux de pêche suggèrent que les albatros modulent leurs réponses en fonction de l’espèce et des contraintes énergétiques, et que les rencontres de bateaux ont peu d’influence sur les stratégies suivies par les individus lors de leur trajet suivant. Ainsi le comportement d’attraction aux bateaux de pêche pourrait être un phénomène local (à l’échelle du rayon de perception) et largement opportuniste. Globalement, nos résultats empiriques ancrés dans un socle théorique solide suggèrent que l’approvisionnement des oiseaux marins ne peut pas se résumer à rencontrer des ressources rares et imprévisibles, et semble pouvoir impliquer des processus de sélection des ressources rencontrées et/ou de choix entre utilisation de mémoire individuelle ou d’information publique. Les ressources anthropiques à ce titre pourraient ne constituer que des ressources parmi d’autres. De nombreux outils d’analyses utilisés ici sont facilement transférables à d’autres oiseaux marins ou d’autres prédateurs à place centrale. Élargir les comparaisons à d’autres organismes est en effet nécessaire pour mieux comprendre les variations complexes mises en évidence ici dans la plasticité comportementale et leurs conséquences vis-à-vis des changements environnementaux. / It is essential to understand how animals make foraging decisions to acquire food in order to better anticipate their responses to environmental changes. Breeding seabirds make central-place foraging trips at sea, from their colony. The deployment of small GPS devices on them reveals that they travel for tens to thousands of kilometers, in search of prey for which very little information is known. The behavioural strategies they use to increase their chances to encounter prey, and the implications of these strategies with regards to human fishing activities remain open questions. This thesis offers to examine these questions in three chapters, through theoretical simulations, empirical analyses of foraging trips of various species and populations of seabirds, and the spatiotemporal matching of seabirds and fishing vessels movements. First, our random walk simulations indicate that straight-line phases within path are not sufficient to conclude that seabirds anticipate where to find their prey, contrary to previous conclusions proposed in the literature. However it is possible and easy to analyze biases in the directions individuals follow when they forage, to infer which sources of information they use to decide where to forage. Second, we compare individual fidelity strategies between species, populations and/or ecological contexts through the use of multivariate statistical models (GLMM). Many seabirds display individual fidelity in the direction they forage from the colony, suggesting they rely on memory. Our results show that this is also the case in different species and populations of tropical seabirds, where individuals can remain faithful to a foraging direction for several consecutive days. These results are surprising and difficult to explain as the species we studied are targeting prey whose distribution is supposedly very stochastic and ephemeral. It suggests that the use of memory might be much more widespread in foraging seabirds than anticipated, at least for decisions at large spatial scales. Finally, our analyses on the responses of albatrosses to fishing boats suggest that their responses can be modulated according to species and energetic constraints, and that encounters of fishing boats during a foraging trip have little influence on the strategy used by individuals on their next foraging trip. The attraction of albatrosses to boats might be mainly a local process (at the scale of the perception range) and may be largely opportunistic. Overall, our empirical results anchored in a solid theoretical framework suggest that seabird’s foraging cannot be summarized as encountering rare and unpredictable resources, but might imply resource selection processes after resources are encountered, and/or a decision as to rely either on memory or public information. With that regard, anthropic resources may only be one type of resources among others for seabirds. Many of the analytical tools used here could be transferred to other seabirds and other central place foragers. Indeed, a wider comparative approach is necessary to understand the complex variations in behavioural plasticity observed here, and their consequences regarding future environmental changes.
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Dinâmica do fósforo de sedimentos oriundos de bacia hidrográfica subtropical compoluição rural e urbana / Phosphorus dynamics in sediments from a subtropical catchment with rural and urban pollutionZafar, Mohsin 23 November 2015 (has links)
Areas at steep slopes in the catchments with high occupation by family farmers in Southern Brazil, even with a high surface covered with regenerated forests, are characterized by the persistence of sources of rural and urban pollution that are undermining the quality of aquatic systems. The unfair use of soil outside its capability, the adoption of inadequate soil tillage systems, the integrated system of animal production (poultry and swine) in quantities environmentally intolerable and the untreated domestic sewage from small villages are the main factors responsible for the input of high amounts of phosphorus into watercourses. In this context, the present doctoral thesis aims (i) monitoring the temporal variation in sediment-bound phosphorus in sub-catchments under different land-use and soil tillage systems and (ii) assessment of the potential of sediments from rural and urban sources to behave as source or sink of phosphorus for aquatic systems. In the Guaporé River catchment, six representative headwater sub-catchments with contrasting land-use and soil management were monitored. The selected sub-catchments were characterized by: (i) predominance of native forest (control); (ii) predominance of areas transformed to agriculture recently, but under conventional tillage CT (sub1); (iii) areas under CT, but with predominance of Ilex plantations (sub2); (iv) predominance of tobacco cultivation of long term under CT (sub3); (v) intensive agriculture under no-tillage NT (sub4); and (vi) intensive agriculture under NT and receiving untreated sewage of a twenty thousand inhabitant town (sub5). In addition, five points of the main river (P1 to P5) were monitored: the first one is located near to the junction of the sub-catchments 4 and 5, and the last one at the outlet of the watershed. Suspended and bed sediments were collected, comprising ten field campaigns performed in the monitoring period of 24 months (October 2012 to October 2014). The different fractions of phosphorus (P) of sediment were analyzed considering the bioavailability. The P sorption-desorption parameters in the sediments were estimated. The conversion of native forest for annual crops production areas promotes the production of sediments with higher amounts of total, inorganic and labile phosphorus. The values of maxima phosphorus adsorption capacity, instantaneous available and potentially available phosphorus forms, desorption rate and mobility index of phosphorus in sediments collected in the different sub-catchments in the following order: native forest < CT < CT with the intensive production of tobacco < NT < NT in the rural area plus urban sewage. A highly positive correlation was observed between different phosphorus fractions (especially the labile phosphorus), as well as different parameters of sorption/desorption, and amounts of iron and aluminum in sediments. It was found the highest amount of labile phosphorus in sediments collected at the end of winter and beginning of spring, particularly in the areas where tobacco is cultivated under CT. / As áreas de bacias hidrográficas declivosas e densamente ocupadas pela agricultura familiar no Sul do Brasil, apesar de apresentarem grande superfície com florestas regeneradas, caracterizam-se pela persistência de fontes de poluição rurais e urbanas que vêm comprometendo a qualidade dos sistemas aquáticos. O uso do solo fora de sua aptidão, a adoção de sistemas de manejo inadequados, o sistema integrado de produção animal (aves e suínos) em quantidades ambientalmente intoleráveis e o não tratamento dos esgotos domésticos das pequenas cidades são fatores responsáveis pelo aporte de grandes quantidades de fósforo aos cursos d água. Nesse contexto, a presente tese de doutorado visa (i) monitorar a variação temporal do fósforo ligado aos sedimentos em sub-bacias com diferentes usos e manejo do solo e (ii) avaliar o potencial dos sedimentos de fontes rurais e urbana em atuarem como fonte ou dreno de fósforo aos sistemas aquáticos.Na Bacia Hidrográfica do Rio Guaporé RS/Brasil foram monitoradas seis sub-bacias de cabeceira representativas de uso da terra e de sistemas de manejo do solo contrastantes. As sub-bacias selecionadas caracterizavam-se por:i) predomínio demata nativa (controle); (ii) predomínio de áreas transformadas em agricultura recentemente, mas sob sistema de cultivo convencional SCC (sub1); (iii) áreas emSCC, mas com predomínio de produção de erva-mate (sub2); (iv) predomínio de áreas emSCC há longa data para cultivo do tabaco (sub3 ); (v) predomínio de agricultura intensiva, mas sob o sistema plantio direto SPD (sub4); e (vi) predomínio de agricultura intensiva sobSPD e recebendo esgoto não tratada de uma cidade com 20 mil habitantes (sub5). Adicionalmente, monitoraram-se cinco pontos no rio principal (P1 a P5), sendo que o primeiro está localizado na junção das sub-bacias 4 e 5 e o último é o exutório da bacia.Coletaram-se sedimentos de fundo e em suspensão, em dez campanhas de campo, durante 24 meses (10/2012 a 10/2014). Foram analisadas as diferentes frações de fósforo no sedimento, de acordo com a biodisponibilidade e estimaram-se os parâmetros de adsortividade e dessortividade do fósforo no sedimento. A conversão da mata nativa para implantação de culturas anuais induz a produção de sedimentos com maiores teores de fósforo total, fósforo inorgânico e fósforo lábil. Os valores da capacidade máxima de adsorção, fósforo instantaneamente disponível, fósforo potencialmente disponível, taxa de dessorção e índice de mobilidade de fósforo dos sedimentos coletados nas diferentes sub-bacias aumentaram na seguinte ordem: mata nativa < SCC < SCC intenso com produção de tabaco < SPD < SPD no meio rural mais esgoto urbano. Foram observadas correlações positivas dasdiferentes frações de fósforo (em especial aquela relacionada ao P lábil), bem como dos diferentes parâmetros de sorção/dessorção, com os teores de ferro e alumínio do sedimento.Foi encontrado maior teor de fósforo lábil nos sedimentos coletados no final do inverno e início da primavera,particularmente naqueles correspondentes aos locais onde se cultiva tabaco em SCC.
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Vespas sociais (Hymenoptera, Vespidae) em áreas antrópicasAlvarenga, Raphaela de Barros 10 February 2012 (has links)
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Previous issue date: 2012-02-10 / As vespas sociais estão amplamente distribuídas em todo o continente. No ambiente urbano tem se observado a nidificação de algumas espécies de vespas sociais em locais próximos a presença humana, como por exemplo, a espécie Mischocyttarus cassununga. Os objetivos deste trabalho foram verificar a ocorrência de vespas sociais em jardins urbanos, durante a estação quente e úmida; e fria e seca e avaliar a agressividade, o comportamento de defesa e o desenvolvimento das colônias de M. cassununga, diante de perturbações nos ninhos e simulação de ataques de formigas, no município de Juiz de Fora, Minas Gerais. Para verificar a ocorrência de vespas sociais em jardins urbanos, o estudo foi conduzido durante um ano, em sete jardins urbanos, com seis vistorias em cada estação. Durante a estação quente e úmida foram encontradas 145 colônias: Protopolybia exigua (n= 81), Polybia platycephala (n=40) e Mischocyttarus cassununga (n=24). Já na estação fria e seca foram encontradas 87 colônias: P. exigua (n=47), P. platycephala (n=29) e M. cassununga (n=11). Na estação quente e úmida a densidade foi superior para todas as espécies. Nas duas estações o índice de dominância para as colônias de P. exigua (d=0,55) foi superior em relação às outras espécies encontradas (d= 0,30 para P. platycephala e d=0,15 para M. cassununga). Todas as colônias nidificavam em vegetação: Livistona chinensis (n=161) e Dracaena fragans (n=71). O número de colônias encontradas demonstrou uma forte correlação positiva com o tamanho da área verde arbórea (r=0,9643; p=0,0005) e com o tamanho da área verde de nidificação (r=0,8571; p=0,0137), assim como com o tamanho da área total dos jardins urbanos(r=0,9286; p=0,0025). A altura das colônias em relação ao solo variou de dois a mais de quatro metros. As espécies que estavam entre dois e quatro metros de altura foi significativamente maior (χ²=21,930; p<0,0001) do que as colônias encontradas nas demais alturas. Para avaliar o comportamento de defesa da espécie M. cassununga, o estudo foi realizado entre os meses de abril a julho de 2011 no campus da Universidade Federal de Juiz Fora, utilizando-se sete colônias controle e sete colônias tratamento. As colônias foram mapeadas e durante 18 dias as colônias tratamento foram perturbadas com uma bola de malha vermelha agitada. Posteriormente foi feita uma simulação de ataque de formigas contra todas as colônias (controle e tratamento). Os resultados mostraram que durante a perturbação com a bola as colônias se apresentaram mais agressivas no começo e possivelmente se habituaram a bola com o decorrer da perturbação. Durante a simulação de ataque de formigas, não houve diferença significativa (z=0,133; p=0,895) na freqüência comportamental entre as colônias controle e tratamento. O desenvolvimento dos imaturos também não demonstrou diferença significativa para ovos
(z=1,351; p=0,177), larvas (z=1,293; p=0,196) e pupas (z=0,925; p=0,355) entre as colônias controle e tratamento. Porém houve uma diferença significativa (z=2,300; p=0,021) no desaparecimento de ovos entre as colônias controle e tratamento. Houve também uma diferença significativa entre o desaparecimento de larvas das colônias controle e tratamento de M. cassununga (z=2,108; p=0,035). Com este estudo foi possível perceber que há uma maior ocorrência das vespas sociais na estação quente e úmida em jardins urbanos e uma relação direta entre a presença de recursos oferecidos nesta estação e a ocorrência de vespas sociais. Foi possível demonstrar também que apesar da baixa agressividade, as colônias de M. cassununga exibem comportamentos agressivos em defesa de suas colônias e que as perturbações influenciam no desaparecimento de imaturos (ovos e larvas), diminuindo o surgimento de novos adultos. / The social wasps are widely distributed around the continent. In the urban environment has been observed the nesting of some social wasps species and their socialization with the human presence, for exemple the specie Mischocyttarus cassununga. The objectives of this study were to verify the occurrence of social wasps in urban gardens during the hot, humid, cold and dry and evaluate their aggression, and colonies defensive behavior development of M. cassununga, about turmoil in nests and of ants attacks simutalions, in the Juiz de Fora municipality , Minas Gerais. To check the occurrence of social wasps in urban gardens, the study was conducted during one year in seven urban gardens, making six surveys at each station. During the hot and humid 145 colonies were found: Protopolybia exigua (n=81), Polybia platycephala (n=40) and Mischocyttarus cassununga (n=24). In the cold season and dry 87 colonies were found: P. exigua (n=47), P. platycephala (n=29) and M. cassununga (n=11). In the hot and humid the density was higher in all species. In two seasons "the" dominance index for colonies of P. exigua (d=0.55) was superior compared to other species found (d=0.30 for P. platycephala and d=0.15 for M. cassununga). All colonies nesting in vegetation: Livistonia chinensis (n=161) and Dracaena fragans (n=71). The number of colonies found showed a strong positive correlation with the size of green tree (r=0.9643, p=0.0005) and with the size of nesting green area (r=0.8571, p=0.0137), as well as the total area size of urban gardens (r=0.9286, p=0.0025). The height colonies from the ground ranged from two tand four meters more. The species that was between two and four meters in height was significantly higher (χ²=21.930; p<0.0001) than those found in other colonies heights. To evaluate the defense of M. cassununga specie, the study was conducted between April and July 2011 on the campus of University Juiz de Fora, using seven control colonies and seven treatment colonies. The colonies were mapped and during 18 days the treatment colonies were disturbed by a agitated restless ball of red. It was later made a mock attack against all ant colonies (control and treatment). The results showed during the disturbance with the ball the colonies had more aggressive in the beginning and possibly have accustomed to the ballduring the perturbation. During the attack simulation by ants, there was no significant difference (z=0.133, p=0.895) in the behavior frequency between control and treatment colonies. The immature development also showed no significant difference for eggs (z=1.351, p=0.177), larvae (z=1.293, p=0.196) and pupas (z=0.925, p=0.355) between control colonies and treatment colonies. However, there was a significant difference (z=2.300, p=0.021) in disappearance of eggs between the control and treatment colonies. There was also
a significant difference between the disappearance of larvae from control and treatment colonies M. cassununga (z=2.108, p=0.035). With this study it was revealed that there is a higher occurrence of social wasps in the hot season and humid in urban gardens and a direct relationship between the features presence offered in this season and the occurrence of social wasps. It was also possible to demonstrate that despite the low aggressiveness, the colonies M. cassununga showed aggressive behavior in defense of their colonies and that disturbances influence the disappearance of immature (eggs and larvae), reducing the emergence of new adults.
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Base de référence, impacts anthropiques et mesure s de protection pour les requins récifaux de Nouvelle - Calédonie / Baseline, human impacts and management measures for reef sharks in New CaledoniaJuhel, Jean-Baptiste 24 February 2016 (has links)
L'impact anthropique sur les écosystèmes coralliens est aujourd'hui largement documenté, que ce soit sur la biodiversité qu'ils hébergent, leur diversité fonctionnelle, les services écosystémiques qu'ils procurent ou leur capacité de résilience. Parmi les groupes trophiques, les prédateurs apicaux en général et les requins en particulier, sont particulièrement sensibles aux perturbations d’origine humaine du fait de leurs traits d'histoire de vie conservateurs (e.g. croissance lente, maturité sexuelle tardive, faible fécondité). D'après certaines estimations, les populations de requins ont décliné de plus de 90% à l'échelle globale. Afin d'assurer le maintien de leurs populations et de leur rôle fonctionnel dans la communauté, il est nécessaire de mettre en place des mesures de gestion adaptées. Les objectifs de cette thèse sont de 1) faire le bilan des populations de requins de Nouvelle-Calédonie ; 2) déterminer l'efficacité des vidéos stéréoscopiques appâtées (S-BRUVS) pour recenser les requins en les comparant aux comptages en plongées (UVC) et évaluer leur possible amélioration ; 3) évaluer l'impact de la proximité humaine sur la diversité, l'abondance et le comportement des requins récifaux et 4) déterminer l'efficacité des mesures de gestion en place pour protéger ces espèces emblématiques. Les résultats des deux méthodes de recensement montrent un important déclin d'environ 90% des abondances de requins récifaux le long d'un gradient anthropique complet en Nouvelle-Calédonie alors que la pêche des requins est historiquement absente dans cet archipel. Une importante altération comportementale du requin gris de récif (Carcharhinus amblyrhynchos) face à la nouveauté d'un appât a été mise en évidence. Les individus se tiennent plus éloigné du dispositif, interagissent moins avec l'appât et mettent plus de temps pour le mordre avec l'augmentation de la proximité humaine. Cette dernière est le principal moteur de ce déclin d’abondance (46 à 71%) et de l'altération comportementale vers des individus plus craintifs (50 à 80%). Globalement, les aires marines protégées de Nouvelle-Calédonie ne sont pas efficaces pour la protection des requins. Néanmoins, la réserve intégrale Merlet héberge des populations de requins proche du niveau de récifs isolés de l’archipel et protège une partie du comportement. Les résultats de ce travail révèlent 1) l'importance et le caractère unique des récifs coralliens isolés ; 2) qu'en absence de pêche la proximité humaine conditionne l'abondance et le comportement des requins de récifs avec des conséquences écologiques potentielles sur l'ensemble du réseau trophique ; 3) que l'efficacité des AMPs réside dans leur capacité à exclure la présence humaine sur une surface suffisamment grande. / Anthropogenic impacts on coral reefs are largely documented through changes in functional diversity, ecosystem services or resilience. Among trophic groups, apex predators in general and sharks in particular are the most sensitive to disturbance due to conservative life history traits (e.g. slow growth, late sexual maturity, low fecundity). By some estimates, shark populations have declined by >90% worldwide. To ensure the sustainability of their populations and their functional role in the reef community, appropriate management measures must be implemented. The aims of this thesis are 1) to assess reef shark populations in New Caledonia; 2) to evaluate the efficiency of stereo baited remote underwater video systems (S-BRUVS) in surveying shark distribution comparing them to underwater visual censuses (UVC) and to evaluate their potential improvements ; 3) to evaluate the impact of human proximity on diversity, abundance and behaviour of reef sharks and 4) to determine the efficiency of management measures currently in place in New Caledonia to protect reef shark populations. The results of S-BRUVS and UVC were congruent and revealed a dramatic decline of shark abundance of ~90% along the anthropogenic gradient in a country where shark fishing is historically absent. An important behavioural alteration of the grey reef shark (Carcharhinus amblyrhynchos) towards bait was highlighted. Individuals remained farther from the device, exhibited more cautious approaches, interacted less with the bait and took longer to bite it as human proximity increased. Human proximity was the main driver of the abundance decline (46 to 71%) and the behavioural alteration towards shier individuals (50 to 80%). Globally, MPAs in New Caledonia are not effective in protecting reef sharks. However, the oldest and most restrictive MPA (Merlet) hosts shark abundance close to that of some remote reefs of the archipelago and partially protect the behaviour of individuals. These results 1) emphasize the unique role of remote coral reefs as the last refuges for sharks ; 2) reveal that in absence of shark fishing, human proximity condition shark abundance and behaviour with potential ecological consequences and 3) indicate that the MPAs efficiency to ensure the protection of reef sharks is effected by their ability to exclude human presence over a sufficiently large area.
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Dynamique de la biodiversité et changements environnementaux en Corse depuis 7000 ans : éclairages paléoentomologiques et paléobotaniques / Biodiversity dynamics and environmental changes in Corsica during the last 7000 years : palaeoentomological and palaeobotanical insightsPoher, Yoann 08 December 2017 (has links)
Cette thèse a pour objectif d’identifier les trajectoires plurimillénaires des écosystèmes de Corse à basse et moyenne altitude sous la triple influence des forçages climatiques, eustatiques et anthropiques à travers l’étude des assemblages d’insectes fossiles et des données paléobotaniques disponibles ou nouvellement acquises. Cette approche multidisciplinaire a été appliquée sur trois séquences sédimentaires prélevées à l’étang du Greco sur l’île Cavallo, au marais de Cannuta et à la tourbière de Bagliettu.Les résultats obtenus révèlent des changements majeurs dans la structuration du couvert végétal. Des signes d’ouverture du paysage apparaissent sur Cavallo et à Cannuta dès 5500-5000 cal. BP. Ils coïncident avec des indices d’activités des sociétés insulaires, lesquelles s’intensifient après 3000 cal. BP et plus particulièrement depuis 1000 ans à Bagliettu. Notre étude suggère que la sensibilité et la réponse des zones humides littorales face à la remontée relative du niveau marin dépend du contexte géomorphologique. Sur l’île Cavallo où le relief est faible, la transgression marine induit une augmentation de la salinité dans l’étang du Greco vers 3700 cal. BP, qui provoque une chute irréversible de la diversité des coléoptères aquatiques et hygrophiles. Au marais de Cannuta, où l’érosion des versants a favorisé la progradation de la plaine alluviale, notre étude montre une diminution de l’influence marine après 5000 cal. BP et une diversification de cette même entomofaune à partir de 1200 cal. BP. À Bagliettu, nous avons démontré l’importance des changements hydro-morphologiques des rivières dans la dynamique des écosystèmes tourbeux attenants et de leur entomofaune. / This thesis aims to define the multi-millennial trajectories of Corsican ecosystems under the climatic, eustatic and anthropic factors via the study of fossil insect assemblages and previous or new palaeobotanical data. This multidisciplinary approach was carried out at low and middle elevation on three sedimentary archives from the Greco pond on Cavallo Island, the Cannuta marsh and the Bagliettu peat-bog. The results reveal major changes in the structure of the vegetation cover over the last 7000 years. Signs of more open landscapes occurred on Cavallo and in Cannuta from 5500-5000 cal. BP. They coincide with bio-markers of insular societies activities, which increased from 3000 cal. BP onward and more particularly during the last 1000 years at Bagliettu.This study also suggests that the sensitivity and the response of coastal wetlands to the relative sea-level rise depend on the geomorphological context. On the low-lying Cavallo Island, marine transgression induced an increase of salt conditions in the Greco pond from 3700 cal. BP, which in turn, caused an irreversible loss of aquatic and hygrophilous beetle diversity. In Cannuta marsh, erosion on catchment slopes favoured the progradation of the coastal floodplain and the results reveal a progressive decrease of the marine influence from 5000 cal. BP as well as a diversification of this entomofauna over the last 1200 years. In Bagliettu, the results show how hydro-morphological changes of the rivers impact the dynamics of adjacent peaty ecosystems and beetle diversity.
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Modelo distribuido de simulación del ciclo hidrológico y calidad del agua, integrado en sistemas de información geográfica para grandes cuencas. Aportación al análisis de presiones e impactos de la directiva marco del aguaPérez Martín, Miguel Ángel 20 January 2023 (has links)
[ES] El agua como recurso natural en condiciones adecuadas para los ecosistemas terrestres y las actividades
humanas es cada vez más escasa, lo cual es origen de tensiones crecientes entre los diferentes grupos
sociales. A esta escasez se suma la capacidad actual del ser humano de modificar significativamente el
ciclo hidrológico, tanto cuantitativa como cualitativamente, por lo que el recurso natural puede verse
mermado, una vez más, de forma importante por las actividades humanas.
La calidad del agua en las masas de agua superficiales y subterráneas depende de las características
naturales de la cuenca así como de las afecciones antrópicas que se producen en la misma, y es un aspecto
determinante de la salud de los ecosistemas acuáticos y de las actividades humanas que se puedan
desarrollar en un territorio.
Actualmente, un paso crucial para poder determinar la situación de las masas de agua y su previsible
evolución futura, consiste en conocer adecuadamente el ciclo hidrológico en su etapa terrestre y como le
afectan las actividades humanas. Debido a que la degradación de la calidad del agua genera
externalidades negativas en el medio ambiente, y finalmente en todas las actividades humanas que
pueden tener un impacto muy elevado, la sociedad europea, consciente de esta situación, establece
mediante la Directiva 60/2000/CE Marco del Agua (DMA) (EC, 2000) el desarrollo de un proceso de
análisis y de actuaciones para mejorar el estado de todas las masas de agua europeas en el año 2015. Uno
de los pasos de este proceso es el “Análisis de Presiones e Impactos”, en el cual se trata de identificar las
presiones que ejercen las actividades humanas y al mismo tiempo relacionarlas con los impactos que se
producen en las masas de agua, de forma que se puedan establecer las medidas necesarias que mayor
efectividad tengan en la mitigación de los impactos de las actividades humanas.
En la presente tesis doctoral se ha desarrollado un módulo o herramienta para la modelación matemática
del ciclo hidrológico y calidad del agua en grandes cuencas hidrográficas, dedicando especial atención a la
componente subterránea y a las relaciones río-acuífero. El objeto de este módulo consiste en poder
construir modelos de simulación que permitan conocer los flujos de agua, con sus características químicas,
que se producen en una cuenca hidrográfica. El módulo PATRICAL (Precipitación Aportación en Tramos
de Red Integrados con Calidad del Agua) permite construir modelos espacialmente distribuidos del ciclo
hidrológico, obteniendo los flujos de agua que se producen en los diferentes puntos de la cuenca y los
niveles piezométricos medios en los acuíferos. Además, incluye la simulación del contenido de nitrato y de
la conductividad eléctrica del agua en el suelo, en el medio no saturado, en los acuíferos y en las aguas
superficiales.
Se ha definido también, en esta tesis, una metodología de aplicación gradual para la realización del
análisis de presiones e impactos establecido en la DMA, de forma que los modelos de simulación que se
construyen con esta herramienta permiten realizar la fase más compleja del análisis de presiones e
impactos y también se podrá, con los mismos, cuantificar el efecto de las medidas que se definan en el
futuro.
La utilidad práctica de la herramienta y metodología desarrollada se demuestra con la aplicación que se ha
realizado, la construcción de un modelo de simulación de una cuenca de gran tamaño como es el ámbito
de la Confederación Hidrográfica del Júcar, con más de 42.000 km2, obteniéndose los flujos de agua que se
producen en la misma y los valores de concentración de nitrato y de conductividad eléctrica en las masas
de agua superficiales y subterráneas. Estos resultados permiten identificar los agentes causantes de las
modificaciones de las condiciones químicas en los diferentes puntos de la cuenca y, además, conocer la
evolución histórica y la tendencia hacia el futuro. / [CA] L'aigua com a recurs natural en condicions adequades per als ecosistemes terrestres i les activitats
humanes és cada vegada més escàs, la qual cosa és origen de tensions creixents entre els diferents grups
socials. A esta escassetat es suma la capacitat actual del ser humà de modificar significativament el cicle
hidrològic, tant quantitativa com qualitativament, motiu pel qual el recurs natural pot veure's minvat, una
vegada més, de forma important per les activitats humanes.
La qualitat de l'aigua en les masses d'aigua superficials i subterrànies depén de les característiques
naturals de la conca així com de les afeccions antròpiques que es produeixen en la mateixa, i és un aspecte
determinant de la salut dels ecosistemes aquàtics i de les activitats humanes que es puguen desenvolupar
a un territori.
Un pas crucial, actualment, per a poder determinar la situació de les masses d'aigua i la seua previsible
evolució futura, consisteix a conéixer adequadament el cicle hidrològic en la seua etapa terrestre i com li
afecten les activitats humanes. Pel fet que la degradació de la qualitat de l'aigua genera externalitats
negatives en el medi ambient i, finalment, en totes les activitats humanes que poden tindre un impacte
molt elevat, la societat europea conscient d'esta situació estableix, per mitjà de la Directiva 60/2000/CE
Marc de les Aigües (DMA) (EC, 2000) el desenvolupament d'un procés d'anàlisi i d'actuacions per a
millorar l'estat de totes les masses d'aigua europees l'any 2015. Un dels passos d'aquest procés és el
“Anàlisi de Pressions e Impactes”, en el qual es tracta d'identificar les pressions que exerceixen les
activitats humanes i, al mateix temps, relacionar-les amb els impactes que es produeixen en les masses
d'aigua, de manera que es puguen establir la mesures necessàries en les activitats humanes que major
efectivitat tinguen en la mitigació dels impactes que es produeixen.
En la present tesi doctoral s’ha desenvolupat un mòdul o ferramenta per a realitzar la modelació
matemàtica del cicle hidrològic i de la qualitat de les aigües en conques hidrogràfiques de gran tamany,
dedicant especial atenció a la component subterrània i a les relacions riu-aqüífer. L'objecte d'aquest mòdul
consisteix a poder construir models de simulació que permeten conéixer els fluxos d'aigua, amb les seues
característiques químiques, que es produeixen a una conca hidrogràfica. El mòdul PATRICAL
(Precipitació Aportació en Trams de Xarxa Integrats amb Qualitat de les Aigües) permet construir models
espacialment distribuïts del cicle hidrològic, obtenint els fluxos d'aigua que es produeixen a diferents
punts de la conca i els nivells piezomètrics en els aqüífers, a més inclou la simulació del contingut de nitrat
i de la conductivitat elèctrica de l'aigua en el sòl, en el medi no saturat, en els aqüífers i en les aigües
superficials.
S’ha definit, en aquesta tesi doctoral, una metodologia d'aplicació gradual per a la realització de l'anàlisi
de pressions e impactes establit en la DMA, de forma que els models de simulació que es construeixen
amb aquesta ferramenta permeten realitzar la fase més complexa de l'anàlisi de pressions e impactes, i
també es podrà, amb els mateixos, quantificar l'efecte de les mesures que es definisquen en el futur.
La utilitat pràctica de la ferramenta i metodologia desenvolupada es demostra amb l'aplicació que s'ha
realitzat, la construcció d'un model de simulació d'una conca de gran tamany, com és l'àmbit de la
Confederació Hidrogràfica del Xúquer de més de 42.000 km2, obtenint-se els fluxos d'aigua que es
produeixen en la mateixa i els valors de concentració de nitrat i de conductivitat elèctrica en les masses
d'aigua superficials i subterrànies. Aquests resultats permeten identificar els agents causants de les
modificacions de les condicions químiques als diferents punts de la conca, i a més, conéixer l'evolució
històrica i la tendència cap al futur. / [EN] Water as natural resource in conditions adapted for the terrestrial ecosystems and the human activities is
more and more scarce, which is origin of increasing tensions between the different social groups. The
present-day capability of the human to modify the hydrologic cycle significantly adds to this scarcity, as
much of quantitative form as of qualitative form, reason why the natural resource can be seen decreased,
once again, of important form by the human activities
Water quality in the superficial and groundwater bodies depends on the natural characteristics of the river
basin and human affections that take place in the same one, and it is a determinant aspect of the health of
the aquatic ecosystems and the human activities that can be developed in a territory.
At the moment, a crucial step to be able to determine the situation of water bodies and its foreseeable
future evolution consists of suitably knowing the hydrologic cycle in its terrestrial stage and as it affect
human activities to it. Because the degradation of the quality of water generates negative external effects in
the environment and finally, in all the human activities that they can have a very high impact, the
European society, conscious of this situation, establishes by means of the Directive 60/2000/CE Frame of
Waters (WFD) (EC, 2000) the development of a analysis process and performances to improve the state of
all the European water bodies in 2015. One of the steps of this process is the “Analysis of Pressures and
Impacts”, in which one tries to identify the pressures that exercise the human activities and at the same
time to relate them to the impacts that take place in the water bodies, so that the necessary measures can
be established that greater effectiveness must to reduce the impacts of the human activities
In this doctoral thesis it has developed a module or tool for the mathematical modeling of the hydrologic
cycle and the quality of water to large basins, dedicating especial attention to the underground component
and relations river-aquifer. The object of this module consist of being able to do simulation models that
allow to know water flows, with their chemical characteristics, that take place in a hydrographic river
basin. The module PATRICAL allows to construct spacely distributed models of the hydrologic cycle,
getting the water flows that are produced in the different points from the river basin and piezometric
levels in the aquifers, in addition includes the simulation of the nitrate contents and of the electrical
conductivity of water in the soil, in means non saturated, in the aquifers and in surface waters bodies.
Besides, in this doctoral thesis has been defined a methodology of gradual application for the
accomplishment pressures and impacts analysis established in the WFD, in order to simulation models
that they are constructed with this tool they allow to make the most complex phase of pressures and
impacts analysis, and also it will be able with them to quantify the effect of the measures that are defined
in the future.
The practical utility of the tool and developed methodology is demonstrated with the application that
have been made, the construction of a simulation model of a large basin, the Júcar River District of over
42,000 km2, obtaining water flows that are produced in the same one and concentration values of nitrate
and electrical conductivity in the superficial and underground water bodies. These results allow to
identify the agents that cause chemical conditions modifications in the different points from the river
basin, and in addition to know the historical evolution and the tendency towards the future / A la Comission of the European Communities por su financiación a través del proyecto "Water resources Management Under Drought Conditions, WAM-ME", contrato ICA3.1999.00014 (Directorate General XII Science, Research & Development); y del proyecto "SEDEMED - Sécheresse et Desertification dans les bassins méditerranées", ref. 2002-02-4.4-1084 (INTERREG III B-Mediterranée Occidentale).
Al Ministerio de Educación y Cultura de España por su financiación a través de la Comisión Interministerial de Ciencia y Tecnología, CICYT mediante el
proyecto "Desarrollo de Elementos de un Sistema Soporte de Decisión para la Gestión de Recursos Hídricos", contrato HID1999-0656 y el proyecto "Sistema de apoyo a la decisión para la gestión cuantitativa, cualitativa y ambiental de cuencas hidrográficas", referencia REN2002/03192. / Pérez Martín, MÁ. (2005). Modelo distribuido de simulación del ciclo hidrológico y calidad del agua, integrado en sistemas de información geográfica para grandes cuencas. Aportación al análisis de presiones e impactos de la directiva marco del agua [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/191462
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