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- Flood analysis with the standardized precipitation index (SPI)Publication . Guerreiro, Maria João; Lajinha, Teresa; Abreu, IsabelThe occurrence of flood spells is difficult to monitor and detect. However, there are some indices that permit to monitor hydrological and climatological conditions in river basins. The SPI (Standardized Precipitation Index) is one of those indices. Though the SPI was originally developed for drought detection and monitoring, it can also be applied to perceive wetter than normal conditions. This study pretends to characterize the relationship between the SPI and annual peak flow occurrences in the Tejo (Portugal) river basin and provide a tool for prediction of high flood risk. Results indicate that SPI satisfactorily explained the development of circumstances leading up to major peak flow events.
- Eco-physiological characterization of the macroinverterbate communities of a very disturbed urban stream (Rio Tinto, Portugal): How they survive?Publication . Jesus, Teresa Maria Gonçalves Moreira de; Monteiro, Álvaro; Guerreiro, Maria João; Abreu, Isabel; Amado, Ana; Costa, Miguel
- Investigating context factors in the strategic management of corporate sustainability integrationPublication . Fonseca, Ana; Abreu, Isabel; Silvestre, Winston JerónimoAdequately understanding the role of context factors in the successful development of corporate sustainability-oriented initiatives is an important step towards an integrative vision of sustainability at the organizational level. In the present research, an extensive and structured literature review enabled the identification of 19 context factors relevant for sustainability integration processes. The importance of these context factors was confirmed through a quantitative exploratory research with 156 experienced sustainability professionals from 42 different countries. The results obtained reveal that Commitment, Engagement, Information, Communication and Trust have the highest levels of perceived importance. The results also indicate that the relative importance of these context factors is higher for small and medium sized companies and for companies located in countries with lower Gross Domestic Product. The role of the context factors was analyzed on the scope of the operational stages of a strategic management framework focusing corporate sustainability integration – the Integrative Sustainability Intelligence model. The main contributions of this paper are: the identification of context factors relevant for corporate sustainability integration processes, combining the perspectives of scholars and sustainability professionals; the analysis of the role of the most relevant context factors in the strategic management of corporate sustainability integration processes, enabling the identification of pathways to promote their successful operationalization.
- Comparative statistical analysis new urban road pavement versus conventional pavement of pervious concretePublication . de Oliveira, Evailton Arantes; Guerreiro, Maria João; Abreu, Isabel; Dinis, Maria Alzira PimentaThis research proposes a variation to pervious concrete pavement, in which a mixture of cement, aggregates and water includes calcium hydroxide additive (Ca(OH)2). This new approach focuses on two main environmental functions: increased permeability of urban soil favoring a decrease of total and peak runoff and resulting reduction of flood occurrence in the cities, and CO2 absorption from the atmosphere, contributing to reduction of the negative impacts caused by the observed increased greenhouse effect in the cities. A series of 40 conventional pervious concrete pavement samples and 30 specimens of the proposed urban pavement were tested in the laboratory for permeability, density, porosity and compression resistance, and monitored for CO2 absorption. Results show that there is an environmental benefit of CO2 sequestration when adding Ca(OH)2 to pervious concrete, but there is also a decrease in its compressive strength and permeability.
- Study of the effect of two wastewater treatment plants (WWTP’s) discharges on the benthic macroinvertebrate communities’ structure of the River Tinto (Portugal)Publication . Jesus, Teresa Maria Gonçalves Moreira de; Monteiro, Álvaro; Abreu, Isabel; Guerreiro, Maria JoãoThe Water Framework Directive (DQA-2000/60/ EC) establishes, as one of its main objectives, the achievement of good ecological status of water bodies and introduces the concept of "ecological status", which includes the study of a broad set of parameters and factors to determining the health of an ecosystem. This work is part of a project whose main objective is the rehabilitation of a small urban river in the north of Portugal, the Tinto river, that presents a high degree of environmental degradation. This work aims to study the effect of the two wastewater treatment plants (WWTP’s) discharges in the structure of the benthic macroinvertebrate communities. The study compares results (metrics and indices) obtained from the analysis of benthic macroinvertebrates samples collected in river sections upstream and downstream of the discharges of WWTP’s, between october 2015 and july 2017, and values of hydro-morphological and physico-chemical parameters. Although the benthic macroinvertebrate communities are very conditioned by the bad status of the Tinto river, in the sections downstream of the WWTP's the macroinvrtebrates communities present characteristics that indicate a higher degree of environmental disturbance.
- Indoor air quality in healthcare units - a systematic literature review focusing recent researchPublication . Fonseca, Ana; Abreu, Isabel; Guerreiro, Maria João; Barros, NelsonThe adequate assessment and management of indoor air quality in healthcare facilities is of utmost importance for patient safety and occupational health purposes. This study aims to identify the recent trends of research on the topic through a systematic literature review following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology. A total of 171 articles published in the period 2015–2020 were selected and analyzed. Results show that there is a worldwide growing research interest in this subject, dispersed in a wide variety of scientific journals. A textometric analysis using the IRaMuTeQ software revealed four clusters of topics in the sampled articles: physicochemical pollutants, design and management of infrastructures, environmental control measures, and microbiological contamination. The studies focus mainly on hospital facilities, but there is also research interest in primary care centers and dental clinics. The majority of the analyzed articles (85%) report experimental data, with the most frequently measured parameters being related to environmental quality (temperature and relative humidity), microbiological load, CO2 and particulate matter. Non-compliance with the WHO guidelines for indoor air quality is frequently reported. This study provides an overview of the recent literature on this topic, identifying promising lines of research to improve indoor air quality in healthcare facilities.
- A study on the accuracy and precision of external mass transfer and diffusion coefficients jointly estimated from pseudo-experimental simulated dataPublication . Abreu, Isabel; Oliveira, F. A. R.; Drumond, M. C.Optimal experimental designs for maximum precision in the estimation of diffusivities (D) and mass transfer coefficients (Kc) for solute transport from/to a solid immersed in a fluid were determined. Diffusion in the solid was considered to take place according to Fick's second law. It was found that the optimal design was dependent on the Biot number. In the range of Biot numbers tested (0.1±200), the first sampling time corresponded to values of fractional loss/uptake between 0.10 and 0.32, and the second sampling time corresponded to values of fractional loss/uptake between 0.67 and 0.82. Pseudo-experimental data were simulated by applying randomly generated sets of errors, taken from a normal distribution with 5% standard deviation, to data calculated using given values of the model parameters. Both optimal and heuristic designs (for which the sampling times corresponded to values of fractional loss/uptake from 0.30 to 0.95) were analyzed. The accuracy and precision of the estimates obtained by non-linear regression were compared. It was confirmed that optimal designs yield best results in terms of precision, although it was concluded that the joint estimation of D and Kc should, in general, be avoided. For intermediate values of the Biot number, reasonably precise and accurate estimates can however be obtained if the experimental error is small. # 1998 IMACS/Elsevier Science B.V
- Temporal variability of precipitation indices at a raingauge station in PortugalPublication . Guerreiro, Maria João; Abreu, Isabel; Lajinha, TeresaO objectivo deste estudo é avaliar variações nos índices de precipitação (precipitação total,intensidade, frequência, duração de dias secos e dias húmidos), que possam ser afectados por alterações climáticas numa estação udométrica, chouto, no período de 1912-2007. Nessa estação não se observam variações significativas na precipitação anual no último século,o aumento de precipitação que se observa em outubro é compensado pela diminuição da precipitação em março. em outubro verifica-se um aumento de dias húmidos consecutivos e em março uma diminuição dos mesmos e um aumento de dias secos consecutivos. The objective of this study is to provide insight on variations of precipitation indices (total precipitation, intensity, frequency, duration of wet and dry spells), that may be affected by climate change at a local raingauge station, chouto, in the period of 1912-2007. While no significant changes in precipitation totals were observed annually within the last century,the precipitation increase observed in the month of october is compensated by a precipitation decrease in march. Also in october, there has been an increase in the length of wet spells, whereas a decrease of these is observed in march, which also shows an increase in length of dry spells.
- Study of the effect of two WWTP’s discharges on benthic macroinvertebrate communities structure of the river Tinto (Portugal)Publication . Jesus, Teresa Maria Gonçalves Moreira de; Monteiro, Álvaro; Guerreiro, Maria João; Abreu, IsabelA diretiva quadro da água (DQA-2000/60/EC ) estabelece como um dos objetivos principais a obtenção de um bom estado ecológico das águas e introduz o conceito de “estado ecológico” de um ecossistema o que inclui o estudo de um amplo conjunto de parâmetros e fatores na determinação da saúde de um ecossistema. Este trabalho é parte de um projeto cujo principal objetivo é a reabilitação de um pequeno rio do norte de Portugal, que corre ao longo de uma área urbana e que apresenta um elevado nível de degradação ambiental e tem como objetivo estudar o efeito das descargas de duas estações de tratamento de águas residuais (ETAR’s) na estrutura das comunidades de macroinvertebrados bentónicos do rio Tinto. O estudo compara resultados (métricas e índices) obtidos a partir da análise de amostras de macroinvertebrados bentónicos recolhidas em troços do rio a montante e a jusante das descargas das ETAR’s entre outubro de 2015 e setembro de 2017 e alguns valores parâmetros hidro-morfológicos e físico-químicos. Os resultados permitem verificar que apesar de as comunidades de macroinvertebrados bentónicos se encontrarem muito condicionadas pelo estado mau estado ecológico geral do rio Tinto, nas áreas a jusante das ETAR’s as mesmas apresentam-se ainda mais perturbadas.
- Environmental implications of CO2 absorption by pervious concrete pavement in urban roadsPublication . Oliveira, Evailton Arantes; Guerreiro, Maria João; Abreu, Isabel; Dinis, Maria Alzira PimentaThis research deals with a new material, made from conventional pervious concrete, but with the addition of two components in its mixture, calcium hydroxide (Ca(OH)2), to improve its carbon dioxide (CO2) absorption properties from the atmosphere, and Scrap Tyre Tubes (STT), a rubber waste from used tyres of vehicle (motorcycles and cars), which makes the new material lighter and contributes to urban sustainability by reusing industrial waste automotive. Conventional pervious concrete has a main property that benefits the environment, which is natural from its porous structure, which is the permeability of the urban pavement, which allows the drainage of rainwater from the urban pavement to the underground, contributing to the reduction of flooding in cities through the infiltration of water into the groundwater. This research sought to improve conventional pervious concrete through additives in its mix to create a new porous material, more efficient at sequestering CO2 from the atmosphere, lighter and reusing rubber waste from used tyres. The porosity of conventional pervious concrete makes this material ideal for carbon dioxide (CO2) sequestration due to the ease of CO2 penetration into its internal structure pore network, which interacts with cement and other additives, which by means of a chemical reaction called carbonation, absorbs CO2 from the atmosphere to form calcium carbonate (CaCO3) in its internal structure, which is an excellent environmental benefit for the materials used in the manufacture of urban pavements, as it makes the urban pavement contribute directly for air quality and for the control of pollution emanating from motor vehicles traveling on urban roads. In this investigation were performed laboratory tests of compressive strength and permeability, because these are the most important properties of conventional permeable concrete that make this building material a porous pavement that can be used on urban roadways, these properties are essential for the new pervious concrete material, were also CO2 volume monitoring in contact with specimens of conventional pervious concrete and specimens of new material, because this environmental benefit of CO2 absorption from the atmosphere is very important for the control of air quality in large metropolis, which have high levels of pollution that affect the life of urban citizens, causing respiratory diseases in old and children. In this research, 40 conventional pervious concrete were manufactured with limestone aggregate, to serve as a control group in the statistical analysis and 10 specimens of the new material of pervious concrete also were manufactured with proportions of 1:0.5:4 (cement:Ca(OH)2:pebble), factor water/cement (w/c) of 0.30, with 5% STT in mix, because the proportion of SST in the mix defines how much waste tyre waste can be reused in the manufacture of this new material. The STT is a non-biodegradable material that occupies a lot of urban space, so it harms the environment and the quality of life of the urban citizen, an alternative to reuse STT in the mix of new pervious concrete material is a very important sustainable solution to modern cities around the world due to the progressive annual increase of this waste tire rubber from automotive industries. In this research the results of the tests served to compare compression and permeability, as well as monitoring the absorption of CO2 from the atmosphere of the different groups. The results of the compressive strength and permeability tests and CO2 volume monitoring were analyzed statistically for normality and the t-Student test. This analysis showed that the improvement of environmental properties harms the physical properties of the new material with compressive strength of 1.25 MPa, permeability of 7.00 mm/s and 5% of STT in the mix of new material of the pervious concrete, however, this new permeable concrete material can be used in non-structural works, such as garden pavement, pedestrian sidewalks, finishes to beautify buildings and condominium facades, etc., due to the environmental benefits it produces and cannot be neglected.