Browsing by Author "Azeiteiro, Ulisses Miranda"
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- CO-tucker: a new method for the simultaneous analysis of a sequence of paired tablesPublication . MENDES, SUSANA; Fernández-Gómez, M. José; Cotrim Marques, Sónia; Pardal, Miguel Ângelo; Azeiteiro, Ulisses Miranda; Galindo-Villardón, M. PurificaciónRelationships between species and their environment are a key com ponent to understand ecological communities. Usually, this kind of data are repeated over time or space for communities and their envi ronment, which leads to a sequence of pairs of ecological tables, i.e. multi-way matrices. This work proposes a new method which is a combined approach of STATICO and Tucker3 techniques and deals to the problem of describing not only the stable part of the dynamics of structure–function relationships between communities and their environment (in different locations and/or at different times), but also the interactions and changes associated with the ecosystems’ dynamics. At the same time, emphasis is given to the comparison with the STATICO method on the same (real) data set, where advan tages and drawbacks are explored and discussed. Thus, this study produces a general methodological framework and develops a new technique to facilitate the use of these practices by researchers. Fur thermore, from this first approach with estuarine environmental data one of the major advantages of modeling ecological data sets with the CO-TUCKER model is the gain in interpretability.
- Predicting zooplankton response to environmental changes in a temperate estuarine ecosystemPublication . Marques, Sónia Cotrim; Azeiteiro, Ulisses Miranda; Leandro, Sérgio Miguel; Queiroga, Henrique; Primo, Ana Ligia; Martinho, Filipe; Viegas, Ivan; Pardal, Miguel ÂngeloA novel strategy that allows to predict the responses of zooplanktonic species to environmental conditions in an estuarine temperate ecosystem (Mondego estuary) is presented. It uses 12 indicator species from the zooplanktonic Mondego database (102 species) that are common members of the different habitats, characterized by their specific hydrological conditions. Indicator-species analysis (ISA) was used to define and describe which species were typical of each of the five sampling stations in a 4-year study (2003–2006). First, a canonical correspondence analysis (CCA) was carried out to objectively identify the species-habitat affinity based on the relationship between species, stations and environmental data. Response curves for each of the zooplanktonic species, generated by univariate logistic regression on each of the independent variables temperature and salinity, were generally in agreement with the descriptive statistics concerning the occurrence of those species in this particular estuarine ecosystem. Species-specific models that predict probability of occurrence relative to environmental parameters like salinity, water temperature, turbidity, chlorophyll a, total suspended solids and dissolved oxygen were then developed for the zooplanktonic species. The multiple logistic models used contained between 1 and 3 significant parameters and the percentage correctly predicted was moderate to high, ranging from 62 to 95%. The predictive accuracy of the model was assured by direct comparison of model predictions with the observed occurrence of species obtained in 2006 (validation) and from data collected in the early 2000s in another Portuguese estuary - Ria de Aveiro (Canal de Mira), a complex mesotidal shallow coastal lagoon. The regression logistic model here defined, correctly suggested that the distribution of zooplankton species was mainly dependent on salinity and water temperature. The logistic regression proved to be a useful approach for predicting the occurrence of species under varying environmental conditions at a local scale. Therefore, this model can be considered of reasonable application (and should be tested in other estuarine systems) due to its ability to predict the occurrence of individual zooplanktonic species associated with habitat changes.
- A review of the order mysida in marine ecosystems: What we know what is yet to be knownPublication . Oliveira, Ana Filipa; Marques, Sónia Cotrim; Pereira, Joana Luísa; Azeiteiro, Ulisses MirandaMysids have a high ecological importance, particularly by their role in marine food chains as a link between the benthic and pelagic realms. Here we describe the relevant taxonomy, ecological aspects such as distribution and production, and their potential as ideal test organisms for environmental research. We also highlight their importance in estuarine communities, trophic webs, and their life history, while demonstrating their potential in addressing emergent problems. This review emphasizes the importance of mysids in understanding the impacts of climate change and their role in the ecology of estuarine communities. Although there is a dearth of research in genomic studies, this review emphasizes the relevance of mysids and their potential as a model organism in environmental assessment studies of prospective or retrospective nature and highlights the need for further research to enhance our understanding of this group’s ecological significance.
- Spatio-temporal structure of diatom assemblages in a temperate estuary. A STATICO analysisPublication . Mendes, Susana; Fernández-Gómez, Maria José; Resende, Paula; Pereira, Mário Jorge; Galindo-Villardón, Maria Purificación; Azeiteiro, Ulisses MirandaThis study examines the spatio-temporal structure of diatom assemblages in a temperate estuary (Ria de Aveiro, Western Portugal). Eighteen monthly surveys were conducted, from January 2002 to June 2003, at three sampling sites (at both high and low tide) along the estuarine salinity gradient. The relationship of diatom assemblages and environmental variables was analysed using the STATICO method, which has been designed for the simultaneous analysis of paired ecological tables. This method allowed examination of the stable part of the environment-diatom relationship, and also the variations of this relationship through time. The interstructure factor map showed that the relationship between the 11 environmental variables and the abundance of the 231 diatom species considered was strongest in the months May and September 2002 and January, February and May 2003. The stable part of the species-environment relationships mainly consisted of a combined phosphate, chlorophyll a and salinity gradient linked to a freshwater-marine species gradient. A more pronounced gradient was observed in January, February and May 2003. Diatom assemblages showed clear longitudinal patterns due to the presence of both marine and freshwater components. May and September 2002 had the least structured gradients with marine-estuarine species appearing in the freshwater side of the gradient. The most complete gradient in February 2003 could be considered, in terms of bio-ecological categories, as the most structured period of the year, with a combination of strong marine influence in the lower zone and freshwater influence in the upper. The best-structured gradients were during periods of a diatom bloom. Stable diatom assemblages (with a strong structure and a good fit between the diatoms and environment) are described and characterized. This study shows the efficiency of the STATICO analysis. The inclusion of space-time data analysis tools in ecological studies may therefore improve the knowledge of the dynamics of species-environmental assemblages.
- Surf zone zooplankton communities from the west coast of the Iberian Peninsula: influence of season, substrate type and environmental factorsPublication . Guerreiro, Milene Alexandra; Marques, Sónia Cotrim; Martinho, Filipe; Azeiteiro, Ulisses Miranda; Pardal, Miguel Ângelo; Primo, Ana LígiaStudies on surf zone zooplankton biodiversity and population dynamics processes remain scarce in comparison to other coastal areas. In this work, we analysed the seasonal (winter/summer) variability of the surf zone zooplankton assemblage structure and copepod biomass of distinct areas with different substrate types (sandy beaches/rocky shores) at the west coast of the Iberian Peninsula (Portugal). Cypris of Cirripedia and Acartia clausi prevailed during summer at both areas. In the winter, Paracalanus parvus and Temora longicornis were the most abundant species at sandy beaches, while Harpacticoida n.id.1 and Euterpina acutifrons dominated at rocky shores. Copepod biomass was higher during the winter and in sandy beaches. Zooplankton showed distinct community structure according to season and substrate type, with Harpacticoids and cirripeds being the main responsible for seasonal differences, while fish eggs and harpacticoids were mainly responsible for differences among substrates. Surf zone assemblages were influenced by temperature, chlorophyll a and local hydrodynamics, which reflects species seasonal reproduction and drift in the water column.
- The bond between Higher Education institutions and society: A scoping review about knowledge transfer and valorisation to promote sustainable developmentPublication . Aleixo, Ana Marta; Leal, Susana; Mano, Margarida; Azeiteiro, Ulisses MirandaThis chapter aims to identify how higher education institutions (HEIs) have operationalised the transfer of knowledge to society in terms of research, development, and innovation; the determinants of this process; and how the knowledge transfer to society contributes to local and regional development and sustainability. Herein, a scoping review was carried out to address this goal. Out of 197 retrieved articles, 30 met the inclusion criteria. These studies concentrate on the following themes: (1) determinants of the knowledge transfer process between HEIs and society; (2) the state of knowledge transfer in HEIs; (3) transfer knowledge to local and regional development; and (4) transfer of knowledge to sustainability. This study concludes that although different determinants influencing this collaboration have been identified, most studies reveal that the transfer level is still at a very early stage.
- Zooplankton distribution in a marine protected area: The Berlengas Natural Reserve, Western Coast of PortugalPublication . Mendes, Susana; Marques, Sónia Cotrim; Azeiteiro, Ulisses Miranda; Fernández-Gómez, Mª José; Galindo-Villardón, Mª Purificación; Maranhão, Paulo; Morgado, Fernando; Leandro, Sérgio MiguelZooplankton distribution in the Berlengas Natural Reserve (Portugal) was studied over a period of one year (February 2006 to February 2007). Monthly sampling was performed at 6 stations, differentiated according to depth and distance to the coastline. The aim of this study was to investigate the overall zooplankton variability through its different dimensions (space vs. time). The Partial Triadic Analysis (PTA) was used to study the spatial variability of the zooplankton community and its dynamics in time and the dynamic trajectories of the zooplankton species for each site. It was possible to distinguish a neritic-ocean gradient of the zooplankton composition and a temporal variability. Four distinct periods can be highlighted considering the distribution of the dates and the arrangement of the species: (i) the first one comprised August to November, (ii) the second one was related to June and July, (iii) the third one associated with spring (April and May) and, (iv) the latest one was related to winter (February, March and December 2006 and January and February 2007). The PTA method showed the similarities between the successive data tables and proved to be useful for investigating biotic structures and detecting spatial-temporal patterns in zooplankton distribution.