Abstraction and use of groundwater for heating buildings in a hard rock environment

In order to turn more efficient the heating of class rooms in the lower floor of the old building of the University of Évora (a XVI century building), five drillings were organised inside the area of the university (Figure 1). The purpose was to use the temperature differential of groundwater in relation to air, by means of a heat exchanger, and use this process to heat the rooms using less energy, turning the heating process less expensive. The wells were drilled in fractured rocks (gneisses), and the purpose was to locate them at least around 100 m one from each other, whilst trying to have a hydraulic connection in-between. From the five initial wells, four were successful in terms of productivity, but just two of them (RA1 and RA2) proved to be hydraulically connected. The wells were equipped with screens for all their drilled depth (100 m), except for the first six meters and some two or three pipes of six meters each, to allow space for the installation for submersible pumps. The length of the installed screens guarantees a good efficiency of the system. In the wells with no connection, the heating system can work using each single well for abstraction and injection, but the process is much less efficient than in the cases where interaction between wells is possible through the rock’s fracture network.

Coastal lagoons and their watersheds as GWDE: a case study in the southwest coast of Portugal

The study of groundwater dependent ecosystems opened the opportunity to involve specialists of different areas of knowledge in order to obtain answers for complex interrelations between groundwater and the associated ecosystems. The actual study, carried out in two coastal lagoons of the Portuguese SW coast, showed the high dependency of the marine life and vegetation of the lagoons and associated streams discharging in the lagoons on the fresh water supply of these two lagoons and the high contribution they receive from groundwater in the dry period, which corresponds to more than half of each hydrologic year. Every year, the lagoons are artificially opened to the ocean for a few days to a few weeks, which dramatically changes the inside salinity. The sensitivity of these ecological niches is demonstrated by the strong dependence that some species that are more sensitive to high salinity waters show in relation to the entrance of freshwater resultant from the discharge of the phreatic aquifer of Sines sedimentary Basin. The great biodiversity of these lagoons and its precarious balance is only possible to preserve if the aquifer continue to act as a regulatory factor of the lagoon’s salinity. The equilibrium can be changed in the event of overexploitation of the phreatic aquifer, which is not at risk in the near future. In a scenario of climate change the lagoons will benefit from a slow increase in groundwater contribution, due to the rise of sea level, which will be accompanied by a rise in groundwater levels in the aquifer near the sea.

Central Algarve karst system tufa-related dynamics, Portugal.

Geomorphological mapping is a powerful instrument improving the geomorphological interpretation and understanding of the processes and forms used in landscape studies, with the ability of organizing different thematic layers in the same map. The presented map provide relevant information about the different geomorphological units of the central Algarve (i.e. the Carboniferous flysch mountains; the Barrocal, with marly and karstified subunits), where a karst system is prominent. Solution karst morphologies and large dry areas are common in the elevated areas of the Barrocal, suggesting deep circulation of groundwater. These recharge areas feed the perched aquifers of the area, where discharge is controlled by the impervious lithologies (clay-rich strata of the turbidites, marls and argilites) in the valley bottoms or other leaks in dammed aquifers. In springs related to the main aquifers tufa are actively being formed and, close coupled to spring location, different tufa depositional systems develop.

Avaliação da vulnerabilidade à contaminação no sistema aquífero Évora-Montemor-Cuba

O principal objectivo desta dissertação é a aplicação de métodos empíricos para proceder à caracterização da vulnerabilidade à contaminação do Sistema Aquífero de Évora Montemor-Cuba, nomeadamente os índices DRASTIC, de Susceptibilidade (IS), GOD e o método EPPNA. A aplicação destes índices permitiu concluir que o Sistema Aquífero de Évora-Montemor-Cuba apresenta a maioria da sua área classificada com um índice de vulnerabilidade à contaminação baixo a moderadamente baixo, enquanto os aquíferos carbonatados apresentam grande parte da sua área classificada com um índice moderadamente alto a alto. O IS revelou-se uma ferramenta extremamente útil para ter uma visão espacial do território do ponto de vista da sua vulnerabilidade, quando associada aos usos do solo. No entanto, a complexidade dos sistemas naturais é sempre maior do que as simplificações necessárias para se poderem utilizar as ferramentas que permitem calcular estes índices, existindo permanentemente imprecisões associadas a estes cálculos. ABSTRACT: The aim of this Project is to apply different methods regarding the assessment of groundwater vulnerability to pollution in the Évora-Montemor-Cuba aquifer, namely the DRASTIC, IS, GOD and EPPNA. The greater area of the Évora-Montemor-Cuba aquifer has a vulnerability to pollution classified as low or moderate to low, while in the limestones aquifers the biggest area is classified as moderate to high or high. The IS index is a very useful tool to provide a spatial intuition of the territory, considering its vulnerability, when associated with the land use. However, the natural systems complexity is bigger than the necessary simplifications introduced in order to use these indexes, nevertheless there are permanent inaccuracies related to these results.

Intenções portáteis: Contributos para o estudo da sociabilidade flutuante entre pessoas e objectos na sua dimensão móvel para uma (des) construção de uma ontologia da arte portátil na contemporaneidade

A questão central que abordamos nesta tese, assenta na génese do pensamento portátil dos nossos objectos não artísticos e artísticos. A portabilidade como sintoma civilizacional, num contexto de crescente mobilidade e transição para modos de vida nómadas e itinerantes nas suas mais heterogéneas expressões. Especula-se, que a génese desta mutação nos estilos de vida que são vertiginosamente acompanhados pela parafernália de objectos que orbitam em nossa volta, numa espiral crescente de portabilidade, esteja na necessidade de busca de novos paradigmas societais, após a falência daqueles que sustentam este modo de vida artificial. ABSTRACT: The central question boarded in this thesis, leys on the genesis of the portability's thought about objects, artistic and non-artistic ones. Portability is seen as a civilizational symptom, in a growing context of mobility and transition to nomadic and itinerant ways of life, in there most heterogeneous manifestations. We speculate that the genesis of this mutation of life styles, that are vertiginously accompanied by all this paraphernalia of objects that orbit around us in a crescent spiral of portability, leys on the necessity to search new social paradigms, after the fall of those that sustain these artificial ways of life.