Cristina Delgado

University of Vigo | UVIGO · Department of Ecology and Animal Biology

The objective of this study was to explore the environmental factors having the greatest influence on the distribution and abundance of epipelic diatom species in different wetlands in southern Spain. We previously defined four groups of conductivity categories: fresh (< 0.8 mS cm⁻¹), oligosaline (< 8 mS cm⁻¹), mesosaline (8–30 mS cm⁻¹) and eusalin...

Cultures in Mediterranean climate zones (MCZs) around the world have long been reliant on groundwater and springs as freshwater sources. While their ecology and cultural sustainability are recognized as critically important, inter-relationships between springs and culture in MCZs have received less attention. Here we augmented a global literature r...

The Mediterranean Region holds significant ecological importance, characterised by its unique climate, biodiversity and the crucial role it plays in global ecosystems. Mediterranean streams are naturally highly-stressed environments mainly due to fluctuations in water quantity. River flow generally varies from perennial to ephemeral and temporary r...

Cultures in Mediterranean climate zones (MCZs) around the world have long been reliant on groundwater and springs as freshwater sources. While their ecology and cultural sustainability are recognized as critically important, inter-relationships between springs and culture in MCZs has received little attention. Here we augmented a global literature...

Aim: Understanding the roles of deterministic and stochastic processes in community assembly is essential for gaining insights into species biogeographical patterns. However, the way community assembly processes operate is still not fully understood, especially in oceanic islands. In this study, we examine the importance of assembly processes in sh...

Mediterranean spring ecosystems are unique habitats at the interface between surface water and groundwater. These ecosystems support a remarkable array of biodiversity and provide important ecological functions and ecosystem services. Spring ecosystems are influenced by abiotic, biotic, and anthropogenic factors such as the lithology of their drain...

Despite the reported allelopathic nature of the Eucalyptus genus, eucalypt leachates have unknown effects on the trophic base of stream green food webs. Eucalypt plantations have increased worldwide, including riparian ecosystems. We aimed to test whether short-term eucalypt leachates might alter water chemistry, periphytic algal biomass and diatom...

Aim The species–area relationship (SAR) is one of the most distinctive biogeographic patterns, but global comparisons of the SARs between island and mainland are lacking for microbial taxa. Here, we explore whether the form of the SAR and the drivers of species richness, including area, environmental heterogeneity, climate and physico‐chemistry, di...

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....

Small rivers support high levels of biodiversity, being especially sensitive to the effects of global change. Temporal records of community composition in minimally impaired streams can be used to explore trends in biodiversity in response to climate change and natural temporal variation. We approached the comparison of two time periods (2003–2008...

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...

Good ecological status is the environmental objective of EU water legislation to be achieved by all European water bodies. However, good ecological status varies depending on national criteria, typology approach, and classification systems used. Since nutrient enrichment is the main cause of river degradation, it is important to establish nutrient...

Rivers are intensively managed worldwide through unprecedented flow regime alterations on a global scale. This has led to an increasing interest in the development of quantitative tools to assess the ecological response of organisms to flow alteration. To date, studies reflect a large diversity of responses that make the intensity and prevalence of...

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...

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...

A large number of diatom-based classification systems have been developed worldwide in recent years. These new systems, together with the oldest, emerged on the need to assess the water quality of rivers, but knowledge on possible divergences resulting from their simultaneous application within a territory is limited. This study aimed to compare th...

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...

Microbial biofilms can be key mediators for settlement of macrofoulers. The present study examines the coupled effects of microbial biofilms and local environmental conditions on the composition, structure and functioning of macrofouling assemblages. Settlement of invertebrates over a gradient of human-impacted sites was investigated on local biofi...

Karst ecosystems are considered as priority environments for the protection of biodiversity on a global scale. This study provides a first comparative analysis of epilithic diatom flora from karst springs in two Mediterranean geographic areas (Spain and Italy) with contrasting characteristics (islands vs mainland). We investigated twenty-three spri...

New multi-proxy analyses were performed on two sedimentary sections from shallow marine ecosystems of Ría de Vigo (NW Iberia) to study the effects of the MIS-3 and early Holocene environmental variability. High-resolution data (microfossils, sedimentary facies, and geochemistry) allowed performing a comprehensive reconstruction of the main environm...

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....

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...

In this study we developed a predictive diatom-based model to assess the ecological status of streams and rivers of Northern Spain. Diatom samples were collected with standard protocols over stones from 676 sites distributed along existing environmental conditions across Northern Spain, during seven years between 2002 and 2008 (n = 1056 samples). T...

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...

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...

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...

International Society of Limnology

Couto-Mendoza, Vieira, and Cobo (2014 DOI: 10.1002/ eco.1528; hereafter CV&C) question the use of combined multimetric indices versus the use of single indices in assessing the ecological status of the new European water legislation (Water Framework Directive, WFD; 60/CE/ 2000). Basically, they intend to ‘show how a simple index can be satisfactory...

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...

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...

In the last years the Water Framework Directive (WFD) has encouraged the development of classification systems to assess the ecological status in permanent rivers and streams, but in temporary streams development has been scarce. Here, we constructed an Invertebrate Multimetric index (INVMIB) to assess the ecological status of temporary streams in...

The Island of Majorca (Spain) is characterized by a Mediterranean climate and a karstic geology that favors the formation of numerous springs and spring–fed streams on the island’s Northwester zone. Water and epilithic diatom samples were collected from two springs and four spring–fed streams, located at altitudes ranging from 0 to 756 m a.s.l., in...

The objective of this study was to evaluate whether biological methods based on epilithic littoral diatoms are a valuable complement to other biological elements for the assessment of the ecological potential of reservoirs in Portugal, in accordance with the requirements of the European Water Framework Directive. The statistical analysis performed...

Diatoms are widely used for the bioassessment of permanent rivers and streams due to their broad distribution and their ability to integrate changes occurring in water composition and quality, but they have rarely been investigated in temporary streams. Water and epilithic diatom samples were collected from 60 sites in temporary streams distributed...

There are many rivers in northwest Spain as a consequence of the mountainous landscape and the granitic geology subjected to Atlantic influences. Water and epilithic diatoms samples were collected at 72 sites in Galicia flowing into the Atlantic Ocean and Cantabrian Sea in summer 2002–2003 and spring 2004. These sites included minimally disturbed s...

The type material of Gomphonema rosenstockianum LANGE-BERT. et E. REICHARDT from La Gomera (Canary Islands, Spain) and epilithic material of rivers from several European countries were examined using light and scanning electron microscopy in order to improve the knowledge on the taxonomical status of the G. rosenstockianum and G. tergestinum (GRUNO...

The European Union (EU)’s Water Framework Directive (WFD) requires that all Member States participate in intercalibration exercises in order to ensure that ecological status concepts and assessment levels are consistent across the EU. This paper describes one such exercise, performed by the countries in the Central/Baltic Geographical Intercalibrat...

The type material of Gomphonema rosenstockianum LANGE-BERT. et E. REICHARDT from La Gomera (Canary Islands, Spain) and epilithic material of rivers from several European countries were examined using light and scanning electron microscopy in order to improve the knowledge on the taxonomical status of the G. rosenstockianum and G. tergestinum (GRUNO...

Se han estudiado los cambios estacionales de las comunidades bentónicas (diatomeas e invertebrados) en un arroyo temporal de la isla de Ibiza (Islas Baleares, España). Los parámetros físico-químicos, índices diatomológicos de calidad y algunos métricos de invertebrados se han utilizado para describir e identificar los cambios temporales que se obse...

This paper examines the interdependence among the different forcing factors in the evolution of the Traba coastal wetland (Galicia, NW Spain) based on lithofacies and diatom analyses of three cores reaching the basement. According to radiocarbon data, the wetland originated 5700 cal yr BP, a time when similar systems on the Atlantic coast of the Ib...