Papers by Rita B Domingues
Estuaries and Coasts
The Ria Formosa coastal lagoon is a highly productive shallow ecosystem in southern Portugal, sub... more The Ria Formosa coastal lagoon is a highly productive shallow ecosystem in southern Portugal, subjected to nutrient inputs from anthropogenic and natural sources. Nutrients are major abiotic drivers of phytoplankton in this system, but their effects on phytoplankton assemblages and the occurrence of nutrient limitation are still poorly understood. The main goal of this study was, thus, to evaluate the occurrence, type, and effects of nutrient limitation on phytoplankton community and specific functional groups in the Ria Formosa coastal lagoon. We conducted nutrient enrichment experiments with factorial additions of nitrogen (N) and phosphorus (P) using natural phytoplankton assemblages from distinct locations in the Ria Formosa, throughout a yearly cycle. Phytoplankton composition and abundance were evaluated using inverted and epifluorescence microscopies, and spectrophotometric methods were used for biomass. Limitation was defined as higher phytoplankton growth following enrichme...
The physical characteristics of the Guadiana estuary and the richness of its adjacent territories... more The physical characteristics of the Guadiana estuary and the richness of its adjacent territories were essential in defining the historical and cultural context of the entire region. The extended navigability of the estuary was fundamental to establish trade routes with the Mediterranean civilizations, namely with the Phoenicians, Greeks, and Carthaginians. These civilizations created several commercial harbors along the Guadiana, namely in Mértola, Alcoutim, Castro Marim and Ayamonte. In these locations the human presence dates back as far as the Neolithic (12,000 to 4,000 BCE) and the Chalcolithic periods (4,000 to 3,100 BCE). Later, the Romans (II BCE to V CE), the Alans (V to VI CE.), the Visigoths (VI to VIII CE), and the Arabs (VIII to XIII CE) successively settled in this Iberian region, until the borders of the continental Portuguese territory were set in the 13th century. The predominant North-South direction of the estuary is intrinsically linked with the definition of the...
DOAJ (DOAJ: Directory of Open Access Journals), Sep 30, 2021
Many models of place attachment and sense of place have proliferated in the last decades, and a c... more Many models of place attachment and sense of place have proliferated in the last decades, and a consensus on the conceptualisation and operationalisation of these constructs is yet to be reached. We aim to contribute to this discussion, by proposing a new model and measurement of sense of place as an overarching construct, using exploratory and confirmatory analyses. Results suggested that sense of place is a second-order factor with four first-order factors: 'place', 'people', 'time', and 'self '. The 'place' dimension integrates emotional content associated with the place and can be loosely compared to the unidimensional place attachment in other models. The 'people' dimension corresponds to the sense of community construct, whereas the 'time' dimension reflects the importance of length of residence and intergenerational transmission. Finally, the 'self ' dimension is more internally focused than the other dimensions, reflecting the role of the place for an individual's distinctiveness and self-esteem. Our 32-item Sense of Place Scale is thus a valid and reliable measure based on a quadripartite structure of the sense of place construct.
Journal of Spatial and Organizational Dynamics, Sep 30, 2021
Luanda Bay and Mussulo Lagoon, situated in Luanda (Angola), are two coastal ecosystems highly sen... more Luanda Bay and Mussulo Lagoon, situated in Luanda (Angola), are two coastal ecosystems highly sensitive to environmental issues, such as climate change, water pollution, eutrophication, and harmful algal blooms. These environmental problems can severely affect the quality of life of coastal populations. In this study, we aim to evaluate several psychological variables, such as environmental risk perception and awareness, sense of place, environmental attitudes, and the overall quality of life of the coastal community in these areas, using a comprehensive questionnaire applied to residents and other ecosystem users. Results indicate that most respondents considered that they possess high knowledge about climate change, water pollution, and ingestion of contaminated seafood. However, regarding eutrophication and harmful algal blooms, most participants reported a low/moderate knowledge. Life experience and the media were reported as the most relevant sources of information on environmental problems. Respondents indicated a moderate risk perception towards environmental risks, and a moderate/high emotional attachment to the place. Residents' perceived quality of life was moderate/good in terms of physical and psychological health, and social relationships, but the environmental component was perceived as weak. Results suggest that improvements in the natural environment are needed to increase the quality of life in these ecosystems.
International Journal of Disaster Risk Reduction, 2021
Abstract Living by the coast is a high-risk choice, but most people do it voluntarily. At Faro Be... more Abstract Living by the coast is a high-risk choice, but most people do it voluntarily. At Faro Beach, a heavily urbanized settlement located on a sandy barrier peninsula exposed to coastal hazards, houses and roads were destroyed due to storm action. However, residents feel safe living there and have no intentions of relocating. The development and implementation of coastal management plans and disaster risk reduction measures require the understanding of psychological drivers of residents’ risk perception and behaviours. Thus, the main goal of this study is to evaluate the relationships between place attachment, risk perception, and preparedness in Faro Beach. We hypothesized that place attachment and past experience with hazards would have a negative effect on risk perception, while risk perception would positively influence preparedness. We administered a self-report questionnaire to 131 residents, and analysed the data using partial least squares modelling. Results show that stronger place attachment is associated with lower risk perception, as residents tend to accept the risk as part of their environment. Experience contributed to higher risk perception in Faro Beach residents, most likely because residents have had direct and personal experience with hazards and are fully aware of the consequences. In addition, risk perception was negatively associated with preparedness; although residents’ risk perception is moderate, probably due to risk normalisation, they still make some preparations to deal with a potential disaster. This study is useful for the design and implementation of more sustainable coastal management plans, as it validates the relevance of affective variables in risk perception and preparedness.
Faro Beach, a heavily urbanized settlement in Ria Formosa, southern Portugal, is highly vulnerabl... more Faro Beach, a heavily urbanized settlement in Ria Formosa, southern Portugal, is highly vulnerable to coastal hazards, namely beach erosion and overwashes caused by storms, that have resulted in house and road damage on several occasions. Despite the risks, local residents accept to live there. Four semi-structured interviews were conducted to understand residents’ beliefs, risk perceptions and preparedness regarding coastal risks. We used a qualitative content analysis to derive manifest contents from the interviews. Three main themes were identified in the interviews: how residents feel about Faro Beach; how they perceive coastal hazards and risks; and how they deal with those risks. Positive feelings regarding Faro Beach were identified in all residents, reflecting a strong sense of place that includes high levels of place attachment, rooting, sense of community and place identity. Residents’ personal experiences with hazards probably undersized their perceptions regarding the ri...
Tese dout., Ciencias do Mar (Ecologia Marinha), Faculdade de Ciencias e Tecnologia, Univ. do Alga... more Tese dout., Ciencias do Mar (Ecologia Marinha), Faculdade de Ciencias e Tecnologia, Univ. do Algarve, 2010
The main goal of this study was to evaluate short-term interactions between increased CO2, UVR an... more The main goal of this study was to evaluate short-term interactions between increased CO2, UVR and inorganic macronutrients (N, P and Si) on summer phytoplankton assemblages in the Ria Formosa coastal lagoon (SW Iberia), subjected to intense anthropogenic pressures and highly vulnerable to climate change. A multifactorial experiment using 20 different nutrient-enriched microcosms exposed to different spectral and CO2 conditions was designed. Before and after a 24-h in situ incubation, phytoplankton abundance and composition were analysed. Impacts and interactive effects of high CO2, UVR and nutrients varied among different functional groups. Increased UVR had negative effects on diatoms and cyanobacteria and positive effects on cryptophytes, whereas increased CO2 inhibited cyanobacteria but increased cryptophyte growth. A positive synergistic interaction between CO2 and UVR was observed for diatoms; high CO2 counteracted the negative effects of UVR under ambient nutrient concentrations. Nutrient enrichments suppressed the negative effects of high CO2 and UVR on cyanobacteria and diatoms, respectively. Beneficial effects of CO2 were observed for diatoms and cryptophytes under combined additions of nitrate and ammonium, suggesting that growth may be limited by DIC availability when the primary limitation by nitrogen is alleviated. Beneficial effects of high CO2 and UVR in diatoms were also induced or intensified by ammonium additions.
Effective coastal management is essential in regions where tourism is a main economic activity. H... more Effective coastal management is essential in regions where tourism is a main economic activity. However, poor communication and disagreement between stakeholders hamper the way decisions are conveyed to residents and home/business owners, potentially affecting economic development. We analysed managers and scientists’ views regarding risk perceptions of Faro Beach (Algarve) residents, contributing to the identification of differences and similarities towards a sustainable management. We used a qualitative content analysis of managers and scientists’ discourses. Managers and scientists recognize that residents, particularly fishermen, are quite knowledgeable about the risks they face by living at the beach. However, scientists and managers believe that residents easily forget about the problems due to an optimism bias and positive previous experience with hazards, that never caused fatalities or serious consequences, leading to an underestimation of the severity of the risks. Manager...
Journal of Experimental Marine Biology and Ecology, 2014
Bottle effects" are one of the most deeply rooted concerns of phytoplankton microcosm studies and... more Bottle effects" are one of the most deeply rooted concerns of phytoplankton microcosm studies and are mainly related to incubation time and sample volume. Sample pre-filtration to remove larger grazers is also a common procedure in experimental phytoplankton ecology studies, particularly in nutrient enrichment experiments. However, the effects of bottle volume and sample pre-filtration on the outcomes of such experiments, particularly on the net growth rates of specific phytoplankton taxa, have never been addressed. Therefore, this study aims to evaluate the effects of different bottle volumes and sample pre-filtration on phytoplankton net growth rates in microcosm experiments. To accomplish this goal, unfiltered and filtered (b 100 μm) water samples, collected in the Guadiana estuary, were nutrient-enriched to avoid nutrient limitation and incubated for 3 days in polycarbonate microcosms with different volumes (0.5 L-8.0 L), inside a plant growth chamber. Phytoplankton composition, abundance, biomass and taxon-specific net growth rates were evaluated throughout the experiment. No systematic significant effects of bottle volume were detected in phytoplankton growth rates. However, sample filtration caused significant changes in phytoplankton composition, with a decline of diatom abundance. Moreover, the removal of large-sized predators and large-sized phytoplankton (diatoms) after sample filtration cascaded down the food web, affecting taxon-specific net growth rates differently. Net growth rates of green algae and eukaryotic picophytoplankton were significantly higher in filtered treatments in respect to unfiltered treatments. Conversely, both diatoms and cryptophytes presented higher net growth rates in unfiltered treatments while net growth rates of picoplanktonic cyanobacteria and plastidic nanoflagellates were not affected by sample filtration. We conclude that, while microcosm volume does not affect results in phytoplankton microcosms, sample pre-filtration may significantly alter the structure of the original phytoplankton community and hence increase the problems associated with the extrapolation of experimental outcomes to the natural environment.
Estuarine, Coastal and Shelf Science, 2014
The large Alqueva dam was built in the early 2000s in the Guadiana River (southern Portugal) and ... more The large Alqueva dam was built in the early 2000s in the Guadiana River (southern Portugal) and has highly controlled the freshwater flowing into the Guadiana estuary, leading to significant changes in the natural hydrological regime. To evaluate the impacts of water restriction and flow regularization on estuarine phytoplankton and their environmental variables, sampling campaigns were conducted in the Guadiana estuary throughout a 14-year period, covering different phases related to the Alqueva dam construction. Significant alterations in phytoplankton and their environmental drivers were observed. In the post-filling period, river flow became more constant throughout the year and its natural seasonal variability, with maxima in the winter and minima in the summer, was greatly reduced, leading to higher river flows in the summer and lower in the winter, in relation to the pre-filling phase. Nutrient and light availability and, hence, phytoplankton dynamics, were greatly affected. Phytoplankton abundance and biomass decreased in the post-filling phase related to a decrease in diatoms and cyanobacteria. Since cyanobacteria blooms in the Guadiana are frequently dominated by toxic species, this constitutes an improvement in water quality. However, the overall decrease in phytoplankton biomass and, specifically, the decline in diatom biomass, will have major consequences for the higher trophic levels that depend on planktonic food.
Estuarine, Coastal and Shelf Science, 2005
Seasonal changes in freshwater flow, leading to alteration of the nutritional environment and hen... more Seasonal changes in freshwater flow, leading to alteration of the nutritional environment and hence affecting phytoplankton composition, will probably be enhanced in the Guadiana estuary (SW Iberia) by the recently built Alqueva dam. The main goal of this study is to assess the relationship between dissolved inorganic macronutrient concentrations and ratios, light availability and phytoplankton succession in the upper estuary of the Guadiana River prior to the completion of the dam. From April to October 2001 three locations along the upper estuary were sampled fortnightly. Several physical and chemical parameters were analysed and phytoplankton composition, abundance and biomass were determined through inverted and epifluorescence microscopy. Phytoplankton showed a uni-modal cycle with a biomass maximum during spring. A relationship between phytoplankton succession and nutrient ratios seemed to exist. In early spring, N:P was high, Si was abundant and a diatom bloom occurred. This bloom collapsed and an increase in green algae abundance was observed later in spring, with low Si and high N:P. In the summer, N:P and Si were low, and a cyanobacteria bloom developed. This bloom included the potentially toxic Microcystis. Light was probably limiting throughout the sampling period, particularly to non-motile cells. Enhancement of cyanobacteria blooms can be expected, and as the river water is used by local human populations, continued monitoring of the Guadiana estuary will be necessary to evaluate the effects of the Alqueva dam construction on phytoplankton dynamics.
Estuarine, Coastal and Shelf Science, 2011
Light is usually the main driver of phytoplankton growth in turbid estuaries, but it has received... more Light is usually the main driver of phytoplankton growth in turbid estuaries, but it has received far less attention than nutrients as a bottom-up factor. This study presents the first experimental analysis of light limitation of phytoplankton growth and production and its seasonal variability in the freshwater tidal reaches of the turbid Guadiana estuary, SE Portugal/SW Spain. Natural phytoplankton communities
Alterations of freshwater flow regimes and increasing eutrophication can lead to alterations in p... more Alterations of freshwater flow regimes and increasing eutrophication can lead to alterations in phytoplankton biomass, composition, and growth in estuaries and adjacent coastal waters. Since phytoplankton is the first trophic level of most aquatic foodwebs, these changes can be propagated to other biological compartments, eventually impacting water quality and ecosystem services. However, phytoplankton responses to environmental changes in abiotic variables (e.g., light, nutrients) are additionally controlled by mortality or removal processes (e.g., grazing, horizontal advection and viral lysis). Grazing exerted by microzooplankton, usually dominated by phagotrophic protists, is considered the most relevant phytoplankton mortality factor in most aquatic systems (see Calbet, Landry 2004). In fact, grazing impact of microzooplankton can prevent phytoplankton accumulation in marine systems despite an overall increase in phytoplankton replication rate. By consequence, microzooplankton grazing may minimize problems associated to increased eutrophication and, ultimately, prevent the occurrence of harmful phytoplankton blooms. Thus, microzooplankton grazing on phytoplankton constitutes a key biological process required to understand and predict relationships between hydrological and biological processes in aquatic ecosystems and to use ecosystem properties to improve water quality and enhance ecosystem services, general principles of the Ecohydrology Concept (Zalewski 2000)
The effects of different phases of semidiurnal and spring-neap tidal cycles on phytoplankton and ... more The effects of different phases of semidiurnal and spring-neap tidal cycles on phytoplankton and environmental drivers were evaluated in a tidal, freshwater location of a mesotidal estuary (Guadiana estuary, SW Iberia). An Eulerian approach was used and sampling covered different seasons during 2008. Samples were collected during spring and neap tides, at high tide, mid-ebb, low tide and mid-flood. Several physical-chemical variables were measured, as well as phytoplankton abundance and biomass.Salinity was higher at high-tide and suspended particulate matter was higher during spring tides and flood, due to higher vertical mixing and resuspension of bottom sediments. Chlorophyll a concentration during winter and summer neap tides was higher than during spring tides, whilst the abundance of pennate diatoms was higher during winter and Spring spring tides than during neap tides, probably reflecting differences in river discharge. Overall, tidally-induced differences detected in the freshwater tidal reaches of the Guadiana estuary were not as considerable as those observed in the lower estuary. However, the occurrence of tidally-induced variability in some seasons reflects that thorough sampling programs to study estuarine tidal dynamics should be conducted throughout the year. Occasional sampling will not reflect the typical variability of these highly dynamic systems. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Journal of Plankton Research, 2014
Increases in ultraviolet radiation (UVR) and CO 2 affect phytoplankton growth and mortality in a ... more Increases in ultraviolet radiation (UVR) and CO 2 affect phytoplankton growth and mortality in a variety of different ways. However, in situ responses of natural phytoplankton communities to climate change, as well as its effects on phytoplankton annual cycles, are still largely unknown. Although temperature and UVR have been increasing in temperate latitudes during winter, this season is still particularly neglected in climate change studies, being considered a non-active season regarding phytoplankton growth and production. Additionally, coastal lagoons are highly productive ecosystems and very vulnerable to climate change. This study aims, therefore, to evaluate the short-term effects of increased UVR and CO 2 on the composition and growth of winter phytoplankton assemblages in a temperate coastal lagoon. During winter 2012, microcosm experiments were used to evaluate the isolated and combined effects of UVR and CO 2 , under ambient and high CO 2 treatments, exposed to ambient UV levels and photosynthetically active radiation (PAR), or to PAR only. Phytoplankton composition, abundance, biomass and photosynthetic parameters were evaluated during the experiments. Significant changes were observed in the growth of specific phytoplankton groups, leading to changes in community composition. The cyanobacterium Synechococcus was dominant at the beginning of the experiment, but it was negatively affected by UVR and CO 2. Diatoms clearly benefited from high CO 2 and UVR, particularly Thalassiosira. Despite the changes observed in specific phytoplankton groups, growth and production of the
Hydrobiologia
Changes in temperature and CO2 are typically associated with climate change, but they also act on... more Changes in temperature and CO2 are typically associated with climate change, but they also act on shorter time scales, leading to alterations in phytoplankton physiology and community structure. Interactions among stressors may cause synergistic or antagonistic effects on phytoplankton dynamics. Therefore, the main goal of this work is to understand the short-term isolated and interactive effects of warming and high CO2 on phytoplankton nutrient consumption, growth, production, and community structure in the Ria Formosa coastal lagoon (southern Portugal). We performed microcosm experiments with temperature and CO2 manipulation, and dilution experiments under temperature increase, using winter phytoplankton assemblages. Phytoplankton responses were evaluated using inverted and epifluorescence microscopy. Overall, phytoplankton growth and microzooplankton grazing on phytoplankton decreased with warming. Negative antagonist interactions with CO2 alleviated the negative effect of temperature on phytoplankton and cryptophytes. In contrast, higher temperature benefited smaller-sized phytoplankton, namely cyanobacteria and eukaryotic picophytoplankton. Diatom growth was not affected by temperature, probably due to nutrient limitation, but high CO2 had a positive effect on diatoms, alleviating the effect of nutrient limitation. Results suggest that this winter phytoplankton assemblage is well acclimated to ambient conditions, and short-term increases in temperature are detrimental, but can be alleviated by high CO2.
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Papers by Rita B Domingues