Salomé Almeida

University of Aveiro | UA · Department of Biology

River and stream ecosystems within cities can provide important Ecosystem Services (ES) to urban population along with the maintenance of biodiversity. Increasing urbanization with land use change can affect biodiversity, impacting ES provision, but the relationships between biota and ES are complex and poorly understood. This study aims to explore...

One of the keys for the rehabilitation or restoration of urban freshwater ecosystems is to promote citizen awareness and their engagement in nature preservation. The environmental educational project CresceRio was created in 2018 in the city of Coimbra, Portugal, assuming the urgency to promote the preservation and rehabilitation of urban streams,...

Gomphosphenia minima sp. nov. is a new freshwater diatom described from central Portugal, found in samples from a mountain stream. The species is described here based on light and scanning electron microscopy. This taxon is compared with other Gomphosphenia taxa such as G. fontinalis, G. lingulatiformis and G. tackei. Gomphosphenia minima sp. nov....

Blue and green ecosystems are considered a key for the improvement of cities sustainability , providing numerous ecosystem services and habitat for many species. However, urban streams are still neglected and degraded, specially in southern European countries. One important step towards the rehabilitation of these ecosystems is the awareness of the...

The southern Iberian Peninsula has a high number of saline ponds where electric conductivity (EC) is an important factor that directly affects the distribution and abundance of aquatic organisms. Environmental factors (such as pH, EC, and temperature) were measured, and diatom assemblages were sampled in 15 shallow saline ponds in southern Spain ov...

Major threats of freshwater systems are river damming and habitat degradation, further amplified by climate change, another major driver of biodiversity loss. This study aims to understand the effects of climate change, and its repercussions on hydropower production, on the instream biota of a regulated river. Particularly, it aims to ascertain how...

The south of the Iberian Peninsula has a high number of saline ponds where electric conductivity (EC) is an important factor that affects directly aquatic organisms, influencing their distribution and abundance. Environmental factors (such as pH, EC and temperature) were measured and diatom assemblages were sampled in 15 saline shallow ponds in the...

During the past decade genetic approaches have been developed to monitor biodiversity in aquatic ecosystems. These enable access to taxonomic and genetic information from biological communities using DNA from environmental samples (e.g. water, biofilm, soil) and methods based on high-throughput sequencing technologies, such as DNA metabarcoding. Wi...

The European Water Framework Directive (2000/60/EC) includes biological assessment of water bodies that has been implemented for many years. Indicator organisms such as diatoms respond to geological and hydrological features of rivers by modifying their structure. Therefore, when implementing the WFD, it was necessary to establish type-specific ref...

The relevance of molecular composition of diatom assemblages to detect river impairment caused by different intensive land uses (industrial, agricultural, and urbanization) was tested in this study with data from two rivers (Ferreira and Sousa rivers) and 21 sampling sites located in the north of Portugal. The Water Framework Directive (WFD) gives...

The biological assessment of rivers i.e., their assessment through use of aquatic assemblages, integrates the effects of multiple-stressors on these systems over time and is essential to evaluate ecosystem condition and establish recovery measures. It has been undertaken in many countries since the 1990s, but not globally. And where national or mul...

This work assesses the effects of river regulation on the diversity of different instream and riparian biological communities along a relieve gradient of disturbance in regulated rivers. Two case studies in Portugal were used, with different river regulation typology (downstream of run-of-river and reservoir dams), where regulated and free-flowing...

Gomphonema alavariense sp. nov. is a new freshwater diatom described in Portugal from phytobenthos samples in an urban pond located in Aveiro (Portugal). This new diatom is illustrated and discussed based on different samples collected in July-August 2017 from Santo António Park pond in the city centre. This taxon was compared with other Gomphonema...

Background: Due to their isolation, islands offer excellent areas for the study of distribution of benthic diatoms. On the other hand, diatoms bearing canal raphe have received less attention compared to other groups of diatoms such as Navicula, Pinnularia or Amphora. Questions: Is it possible that thermal springs on islands offer a refuge for inf...

Background: Thermal springs provide extreme ecological conditions for aquatic communities owing to their high water temperature and particular water chemistry. The thermal springs and their connected watercourses provide a thermal laboratory by offering a wide range of temperatures within short spatial distances. To date, the information on how the...

Artificial ecosystems are sometimes the only opportunity for citizens to experience nature. Keeping their quality is essential for maintaining ecosystem services. We studied an urban pond in the Northwest Iberian Peninsula (Aveiro, Portugal) as a model for testing the suitability diatom assemblages and indices of water quality in such systems. Week...

Diatoms are a compulsory biological quality element in the ecological assessment of rivers according to the Water Framework Directive. The application of current official indices requires the identification of individuals to species or lower rank under a microscope based on the valve morphology. This is a highly time-consuming task, often susceptib...

Freshwaters are constantly facing ecosystem functioning alterations and loss of biodiversity driven by multiple anthropogenic and natural stressors, that by acting simultaneously create complex interactions, affecting the quantity and quality of water resources. Stream biofilms are complex communities, which are exposed to these alterations and, in...

Aljustrel mining area (South Portugal) is a part of the Iberian Pyrite Belt and encloses six sulfide mineral masses. This mine is classified of high environmental risk due to the large tailings’ volume and acid mine drainage (AMD)-affected waters generated by sulfides’ oxidation. The use of biological indicators (e.g., diatoms) revealed to be an im...

One of the most common anthropogenic impacts on river ecosystems is the effluent discharge from wastewater treatment plants. The effects of this contamination on stream biota may be intensified in Mediterranean climate regions, which comprise a drought period that leads to flow reduction, and ultimately to stagnant pools. To assess individual and c...

Benthic diatom communities are used in the ecological assessment of Portuguese rivers through the calculation of an autecological index, the IPS (Indice de Polluosensibilite Specifique), officially adopted for Portugal. This index requires a high level of taxonomic expertise for morphological identification of individuals at species level. Advances...

This study presents major and trace element data and ⁸⁷Sr/⁸⁶Sr ratios for surface waters from a small watershed draining the Aljustrel sulphide mining area (South Portugal). The watershed is located in a geologically complex area comprising two main compartments: the northern compartment is dominated by Cenozoic formations and does not bear any min...

A new freshwater diatom species was described from southwest Europe (Portugal), based on morphological and ultrastructural characteristics. Fragilaria misarelensis Almeida, C.Delgado, Novais & S.Blanco is characterised by lanceolate valves, with slightly capitate ends, alternate striae and lacking spines joining adjacent cells, which are solitary....

A Diretiva Quadro da Água veio obrigar todos os estados membros a procederem a uma monitorização ecológica dos seus rios tendo em vista a avaliação da sua qualidade. Esta classificação deve refletir a qualidade de diversos compo-nentes de um ecossistema ribeirinho, tais como os elementos biológicos, físico-químicos e hidromorfológicos. Com base nes...

As águas termo-minerais apresentam diferentes quantidades de sais minerais que dependem do tempo e da natureza das rochas com as quais a água esteve em contacto. Dentro destas, as águas termais são aquelas cuja temperatura é mais elevada que a temperatura ambiente, em pelo menos 5°C. Portugal é um dos países da Europa mais rico neste tipo de ocorrê...

Organic contaminants, and herbicides in particular, represent a risk for aquatic ecosystems. The primary target of herbicides are producers, the base of food webs, but frequently they end up far from the application point affecting non-target species. Its presence can work as sub-lethal stimulus, which sort the genetic and phenotypic differences wi...

Freshwater ecosystems are under threatening anthropogenic pressures worldwide, namely by metals. Diatoms are used as water quality indicators, but the influence of micronutrients such as Zn and its impacts are poorly understood. Thus, our study aimed to elucidate the tolerance level, the cellular targets and the responses to counteract Zn toxicity...

Metals are a recognised threat to aquatic organisms but the impact of metals such as copper (Cu) on benthic freshwater diatoms is poorly understood, even if diatoms are commonly used as water quality indicators. Our study aimed to elucidate the cellular targets of Cu toxicity and the mechanisms cells resort to counteract toxicity and to increase to...

Biofilm is an important component of small streams and it is highly sensitive to variations in water temperature, therefore it is expectable that the warming predicted for this century will be reflected in its communities. In this study we investigated the effects of experimental warming on biofilm growth in a small forest stream in Central Portuga...

Diatoms are used as indicators of freshwater ecosystems integrity. Developing diatom-based tools to assess impact of herbicide pollution is expected by water managers. But, defining sensitivities of all species to multiple herbicides would be unattainable. The existence of a phylogenetic signal of herbicide sensitivity was shown among diatoms and s...

El principal problema de las explotaciones mineras de sulfuros es la contaminación de los recursos hídricos por procesos de Drenaje Ácido de Mina (AMD). El proceso contaminante provoca, además, la aparición de ecosistemas estructuralmente simples dominados por organismos acidófilos, ya sean procariotas o eucariotas. Desde una perspectiva de monitor...

Contemporary large-scale river ecology is grounded on the existence of patterns in the distribution of aquatic communities, structured by prevailing abiotic conditions. Here, we investigated the existence of functional consistent associations of traits (i.e., traits appearing consistently together at different sites and the same river type) between...

Although diatoms are important bioindicators of ecological quality, their ecological traits are still not well understood. A major issue is that of substrate preferences, which may result in differences in production, and assemblage structure and composition, and which should therefore be taken into account for ecological quality assessment studies...

A new benthic freshwater diatom, Fragilaria rinoi Almeida & C.Delgado sp. nov., is described from river periphyton samples in Portugal. Fragilaria rinoi sp. nov. is illustrated and discussed based on populations collected from the Vouga, Mondego and Lis river basins in central Portugal and compared with the type material of Fragilaria vaucheriae (K...

A great investment has been done in the last decades in the development of numerical and qualitative assessment methods to classify the ecological quality of water bodies. Yet, in spite of all attempts to avoid subjectivity, expert judgment is still used at numerous steps of the ecological classification and is considered by some authors as indispe...

Contemporary bioassessment methods for water bodies require the description of "reference conditions" representing an absence or only "very minor" presence of human impacts on hydromorphological, physical and chemical properties. However, minimally disturbed reference sites are lacking in many European regions and other parts of the world because o...

Intraspecific variability occurs in all types of organisms and is a driving force to speciation, conferring genotypic and phenotypic differences that enable adaptive responses to sub-lethal stimuli such as exposure to pollutants (including cadmium, Cd). Thus, differences in biochemical parameters are expected among isolates of the same species. Stu...

International Society of Limnology

Investigations on organism ecology, biodiversity and biogeography often use large compiled datasets to extract information on species ecological preferences, which then can be used in environmental assessment. Freshwater benthic diatoms are commonly used in this context. However, it is important that the taxonomic information of the separate diatom...

This work presents a combination of geochemical, mineralogical, and biological data obtained in water reservoirs located in one of the most paradigmatic mining regions, suffering from acid mine drainage (AMD) problems: the Iberian Pyrite Belt (IPB). Four water reservoirs located in the Spanish sector of the IBP, storing water for different purposes...

Fragilaria candidagilae Almeida, C. Delgado, Novais & S. Blanco is a new araphid diatom species, described from samples collected in central and southern Portugal (SW Europe). Fragilaria candidagilae has linear-lanceolate valves with strongly capitate apices, without spines, and alternate punctate striae. This taxon presents siliceous plaques on th...

Aljustrel mines were classified as having high environmental hazard due to their large tailings volume and high metal concentrations in waters and sediments. To assess acid mine drainage impacted systems whose environmental conditions change quickly, the use of biological indicators with short generation time such as diatoms is advantageous. This s...

This work presents a combination of geochemical, mineralogical, and biological data obtained in water reservoirs located in one of the most paradigmatic mining regions, suffering from acid mine drainage (AMD) problems: the Iberian Pyrite Belt (IPB). Four water reservoirs located in the Spanish sector of the IBP, storing water for different purposes...

Modern ecological assessments of running waters are based on the a priori definition of ecological benchmarks, given by reference-quality sites. Such benchmarks are established at the level of ecoregions, typologies, or site. Yet, in highly disturbed regions, such as coastal areas of European countries, the assessment of streams’ water quality base...

Alterations in trait proportions of diatom and aquatic macroinvertebrate communities were used to evaluate the consequences of the drying of temperate perennial streams due to an uncommon drought event. Four Atlantic-temperate Portuguese streams were sampled on three occasions; spring before the drought, 2 weeks after the return of water to the str...

Portugal faced an uncharacteristic hydrological drought in the fall/winter of 2011-2012 Small, typically perennial streams were affected by this extreme event and many dried out. Five of these streams were examined during six sampling events between spring 2011 (pre-drought) and spring 2012 (post-drought) to analyse the effects of this disturbance...

Maturation experiments of volcanic mud samples with mineral water were followed up during 120 days at constant room temperature (20 ºC) in order to track geochemical modifications induced by the process and, eventually, the development of diatom communities. Different abiotic conditions were tested during the experiments. Mud samples were collected...

Periphytic communities are good indicators of river quality due to their general sensitivity to several pollutants. The primary objective of this study was to develop and optimize an ecotoxicological testing methodology using the freshwater benthic diatom Navicula libonensis. This species was selected due to its ubiquity and suitability for use und...

An indoor channel system was colonised with fluvial biofilms to study the chronic effects of high Fe and SO4 2− concentrations and acidic pH, the water chemistry in the surrounding streams of Aljustrel mining area (Alentejo, Portugal), and their contribution to community (in)tolerance to metal toxicity by short-term experiments with Cu and Zn. Biof...

To understand whether seasons influence the ecological quality assessment of streams on the basis of diatoms, a study was undertaken in two lowland water courses located in northwest Portugal, between autumn 2008 and summer 2009. Temporal variation in the chemical pollution of these streams was small as revealed by a number of physical and chemical...

Phytochelatins (PCs) are thiol-rich peptides, enzymatically synthesized by plants and algae under exposure to certain metals (Cd, Pb, Zn, Ag, As, Cu). Due to their ability to bind metal ions, they play an important role in the cellular detoxification, forming stable metal-PC complexes that minimize the intracellular deleterious effects of metals. T...

The present study aimed to determine if a predictive model integrating freshwater assemblages from different trophic levels (macroinvertebrates and diatoms) produces a more sensitive assessment of stream health than single-assemblage assessments combined a posteriori. For this purpose, individual and combined models based on two approaches (BEAST a...

Volcanic areas are hostile environments where the release of toxic gases is added to the low pH and high temperature, subjecting living organismsthermal spring, mineral spring, temperature, hydrogeochemistry to extreme conditions. High-temperature environments, particularly those associated with volcanic activity have been evolving on earth through...

p>La presencia de depósitos minerales es muy común en microorganismos, plantas, hongos y mamíferos. Estos organismos son, por lo tanto, un modelo natural excelente para estudiar la relación entre las principales partes que los componen, es decir la fase biopolímérica y la mineral. La importancia de este tipo de estudios se relaciona directamente co...

This study compares regional differences in benthic diatom communities exposed to similar stresses in Canada and Portugal. Diatoms were sampled in the Agua Forte Stream, Aljustrel (SW Portugal) and in the Little River, New Brunswick (SE Canada), both streams surround the respective zinc mine and are subject to similar metal (e. g. Cd, Cu, Fe, Zn) a...

The ubiquity of diatom distribution, species richness, short generation time, and specific sensitivity to several environmental stressors such as metals, make diatoms particularly useful for scientific studies. Anthropogenic activities have increased the concentration of metals in air, soil and water. Due to their toxicity and persistent character,...

In 2009, seventeen analysts participated in a pan-European diatom ring-test (intercalibration), analyzing nine samples from seven countries following the European standard EN 14407. The objective of this exercise was to agree on practical conventions on diatom identification to facilitate future intercalibration work and to assess the extent to whi...

A predictive model for diatoms based on an adaptation of the River Invertebrate Prediction and Classification System/Australian River Assessment System approaches was evaluated as an effective tool for measuring stream ecological quality. This type of model was originally developed in UK and later in Australia and is extensively used to obtain ecol...

The Mediterranean Rivers Geographic Intercalibration Group developed a 3-step approach that allowed the characterization of the best available condition of four Mediterranean common stream types, regarding organic contamination and nutrients, hydrological and morphological alterations and land use. For this purpose, a common database composed of 7...

Biosilica from diatoms is formed at ambient conditions under the control of biological and physicochemical processes. The changes in growth and biosilica formation through uptake of different concentrations of Cd2+ by the diatom Nitzschia palea (Kützing) W. Smith was investigated, correlating Cd2+ effects to changes in the biosilica nanostructure a...

The European Union (EU) Water Framework Directive depends, for effective implementation, on Member States (MSs) agreeing to a concept of the unimpacted “reference” state, which will then provide the “expected” value in Ecological Quality Ratio (EQR) calculations. Reference assemblages of organism groups will, in turn, vary, due to geological, hydro...

In 2009, seventeen analysts participated in a pan-European diatom ring-test (intercalibration), analyzing nine samples from seven countries following the European standard EN 14407. The objective of this exercise was to agree on practical conventions on diatom identification to facilitate future intercalibration work and to assess the extent to whi...

The aim of this work is to clarify the effect of using diatom assemblages from different substrates, and applying different methods, to assess water quality. This issue is of major importance for environmental monitoring especially where the proposed substrate (usually stones) is absent and when diverse methods are used. For this, different substra...

Lousal mine is a typical "abandoned mine" with all sorts of problems as consequence of the cessation of the mining activity and lack of infrastructure maintenance. The mine is closed at present, but the heavy metal enriched tailings remain at the surface in oxidizing conditions. Surface water and stream sediments revealed much higher concentrations...

Diatoms and macroinvertebrates have been extensively used as water quality indicators in Europe for the last two decades. In Portugal, the use of biological indicators to assess water quality in rivers has increased greatly. The aim of this work was to assess the water quality and ecological status o