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Sonia Cotrim Marques - One of the best experts on this subject based on the ideXlab platform.
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spatial distribution and seasonal patterns of the siphonophores muggiaea atlantica and muggiaea kochii in a temperate Estuarine Ecosystem
Estuarine Coastal and Shelf Science, 2019Co-Authors: Mariaelena Dambrosio, M A Pardal, Ana Ligia Primo, Filipe Martinho, Elena Guerrero, Sonia Cotrim MarquesAbstract:Abstract This study analysed the distribution and abundance of both polygastric (asexual) and gonophores of the calycophoran siphonophores Muggiaea atlantica and Muggiaea kochii in the Mondego estuary (Portugal), as well as the influence of local environment and prey availability on the observed patterns. Samples were collected in three different zones of the estuary, from December 2013 to November 2015. In general, both species nectophores and total gonophores followed a similar trend, with higher abundances during spring-summer periods and increased densities in the downstream areas of the estuary, where the marine influence is stronger. Inter-annual differences occurred mainly for M. atlantica nectophores, which showed higher abundances in 2015, particularly in the upstream areas. Both species displayed a shift in the annual peak abundance, from bimodal in 2014 to unimodal in 2015. Patterns observed were not only strongly related with an increase of the marine influence in the estuary, but also with the presence of zooplanktonic prey, such as cirripede cypris, calanoid nauplius, Poecilostomatoida, and copepodites of Cyclopoida. This study represents a step towards a better knowledge of the biology and ecology of siphonophores.
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predicting zooplankton response to environmental changes in a temperate Estuarine Ecosystem
Marine Biology, 2008Co-Authors: Sonia Cotrim Marques, Ulisses Miranda Azeiteiro, Sergio Leandro, Henrique Queiroga, Ana Ligia Primo, Filipe Martinho, Ivan Viegas, Miguel ângelo PardalAbstract:A 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.
Joao Carlos Marques - One of the best experts on this subject based on the ideXlab platform.
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valuing the non market benefits of Estuarine Ecosystem services in a river basin context testing sensitivity to scope and scale
Estuarine Coastal and Shelf Science, 2016Co-Authors: Rute Pinto, Joana Patricio, Roy Brouwer, P Abreu, Cristina Martapedroso, Alexandra Baeta, Joao N Franco, Tiago Domingos, Joao Carlos MarquesAbstract:A large scale contingent valuation survey is conducted among residents in one of the largest river basins in Portugal to estimate the non-market benefits of the Ecosystem services associated with implementation of the European Water Framework Directive (WFD). Statistical tests of public willingness to pay's sensitivity to scope and scale are carried out. Decreasing marginal willingness to pay (WTP) is found when asking respondents to value two water quality improvement scenarios (within sample comparison), from current moderate water quality conditions to good and subsequently excellent ecological status. However, insensitivity to scale is found when asking half of the respondents to value water quality improvements in the estuary only and the other half in the whole basin (between sample comparison). Although respondents living outside the river basin value water quality improvements significantly less than respondents inside the basin, no spatial heterogeneity can be detected within the basin between upstream and downstream residents. This finding has important implications for spatial aggregation procedures across the population of beneficiaries living in the river basin to estimate its total economic value based on public WTP for the implementation of the WFD.
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a biological trait approach to assess the functional composition of subtidal benthic communities in an Estuarine Ecosystem
Ecological Indicators, 2012Co-Authors: Pieter Van Der Linden, Joana Patricio, Agnese Marchini, Joao M Neto, Joao Carlos MarquesAbstract:Within transitional/Estuarine environments ‘Ecosystem functioning’ has been mostly investigated with “traditional” taxonomic analysis, based on the taxonomic composition of benthic invertebrate communities. However, ‘Ecosystem functioning’ depends also greatly on the functional characteristics (biological traits) of organisms. It was a priori suggested that the biological traits of the subtidal benthic invertebrate communities within an Estuarine environment would respond to the high variability of environmental pressures (natural and human induced) within this type of Ecosystem. For this study, traditional taxonomic analysis (species richness, species density and Shannon–Wiener diversity) as well as biological trait analysis were used together for the first time to investigate the response of the subtidal benthic invertebrate communities to the environmental pressures within the Mondego estuary (Portugal). Biological trait analysis, in addition to traditional taxonomic analysis provided a more comprehensive understanding of the functioning within this type of Ecosystem. Some of the most important outcomes are: (i) the trait “salinity preference” was the most important trait that distributed the species along the estuary, (ii) the central part of the estuary appeared to be under higher environmental stress levels than the other areas, as suggested by a dominance of some “opportunistic” traits (e.g. small short-lived species), (iii) the ratio between functional diversity (FD) and Shannon–Wiener diversity (H′) indicated lower functional redundancy at the upper reaches of the estuary. Our results, suggest that the ratio (FD/H′) might be a helpful tool to visualize this functional attribute and could potentially be applied to different communities from distinct environments. Using the traditional taxonomic analysis alone, this last functional aspect would not be detectable. Therefore, the inclusion of biological traits analysis is recommendable for Estuarine ecological studies.
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impact of eutrophication and river management within a framework of Ecosystem theories
Ecological Modelling, 2003Co-Authors: Joao Carlos Marques, M A Pardal, Soren Nors Nielsen, Sven Erik JorgensenAbstract:Eutrophication became a dominant process in the Mondego Estuarine system in the 1980s, presumably as a result of excessive nutrient release into coastal waters. The main symptoms were the occurrence of seasonal blooms of Enteromorpha spp., green macroalgae, and a drastic reduction of the Zostera noltii meadows. Previous results suggest that this process will determine changes in species composition at other trophic levels. This paper aims at integrating the available information to provide a theoretical interpretation of the recent physicochemical and biological changes in the Mondego Estuarine Ecosystem, which will be further used as basic framework for the development of a structurally dynamic model. Exergy-based indices, the Exergy Index and Specific Exergy, were applied as ecological indicators (orientors) to describe the state of the Ecosystem, taking into account different scenarios along a spatial gradient of eutrophication symptoms. This allowed elucidating the present conditions along the spatial gradient as representing various stages in the temporal evolution of the system, within the framework of bifurcation, Chaos, and Catastrophe theories. Eutrophication appeared as the major driving force behind the gradual shift in primary producers from a community dominated by rooted macrophytes (Z. noltii) to a community dominated by green macroalgae. Through time, concomitant changes at other trophic levels will most probably give origin to a new trophic structure. Moreover, river management emerged as a key question in establishing scenarios in order to determine secondary effects in eutrophied systems. Results suggest that a more conservative river management may be used as a powerful tool to remedy affected areas, including the implementation of ecological engineering principles in different possible management practices. The recent biological changes in the Mondego Estuarine Ecosystem were found to comply with the framework of the theories considered, while both Exergy-based indices were able to capture the state of the system and distinguish between different scenarios.
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short and long term effects of eutrophication on the secondary production of an intertidal macrobenthic community
Marine Biology, 2003Co-Authors: M Dolbeth, M A Pardal, Ana I Lillebo, Ulisses Miranda Azeiteiro, Joao Carlos MarquesAbstract:Secondary production of a macrobenthic community at an intertidal mudflat was estimated for 33 successive months. Sampling was carried out along a eutrophication gradient, including non-eutrophied Zostera meadows, an intermediate muddy area, and a strongly eutrophied sand-muddy flat, where macroalgal blooms of Enteromorpha spp. usually occur. The Zostera meadows were always the most productive habitat (145–225 g ash-free dry weight m−2 year−1). In the short term, the macroalgal bloom benefited the total Estuarine production by enhancing the annual production in the eutrophied area. Nevertheless, our results show that this increase was short lived and in no way sufficient to match the production in the Zostera meadows. In the long term, the present study provides evidence that the disappearance of macrophyte beds, as a result of ongoing eutrophication, constitutes a major threat to the sustainability of the Estuarine Ecosystem.
M A Pardal - One of the best experts on this subject based on the ideXlab platform.
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spatial distribution and seasonal patterns of the siphonophores muggiaea atlantica and muggiaea kochii in a temperate Estuarine Ecosystem
Estuarine Coastal and Shelf Science, 2019Co-Authors: Mariaelena Dambrosio, M A Pardal, Ana Ligia Primo, Filipe Martinho, Elena Guerrero, Sonia Cotrim MarquesAbstract:Abstract This study analysed the distribution and abundance of both polygastric (asexual) and gonophores of the calycophoran siphonophores Muggiaea atlantica and Muggiaea kochii in the Mondego estuary (Portugal), as well as the influence of local environment and prey availability on the observed patterns. Samples were collected in three different zones of the estuary, from December 2013 to November 2015. In general, both species nectophores and total gonophores followed a similar trend, with higher abundances during spring-summer periods and increased densities in the downstream areas of the estuary, where the marine influence is stronger. Inter-annual differences occurred mainly for M. atlantica nectophores, which showed higher abundances in 2015, particularly in the upstream areas. Both species displayed a shift in the annual peak abundance, from bimodal in 2014 to unimodal in 2015. Patterns observed were not only strongly related with an increase of the marine influence in the estuary, but also with the presence of zooplanktonic prey, such as cirripede cypris, calanoid nauplius, Poecilostomatoida, and copepodites of Cyclopoida. This study represents a step towards a better knowledge of the biology and ecology of siphonophores.
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impact of eutrophication and river management within a framework of Ecosystem theories
Ecological Modelling, 2003Co-Authors: Joao Carlos Marques, M A Pardal, Soren Nors Nielsen, Sven Erik JorgensenAbstract:Eutrophication became a dominant process in the Mondego Estuarine system in the 1980s, presumably as a result of excessive nutrient release into coastal waters. The main symptoms were the occurrence of seasonal blooms of Enteromorpha spp., green macroalgae, and a drastic reduction of the Zostera noltii meadows. Previous results suggest that this process will determine changes in species composition at other trophic levels. This paper aims at integrating the available information to provide a theoretical interpretation of the recent physicochemical and biological changes in the Mondego Estuarine Ecosystem, which will be further used as basic framework for the development of a structurally dynamic model. Exergy-based indices, the Exergy Index and Specific Exergy, were applied as ecological indicators (orientors) to describe the state of the Ecosystem, taking into account different scenarios along a spatial gradient of eutrophication symptoms. This allowed elucidating the present conditions along the spatial gradient as representing various stages in the temporal evolution of the system, within the framework of bifurcation, Chaos, and Catastrophe theories. Eutrophication appeared as the major driving force behind the gradual shift in primary producers from a community dominated by rooted macrophytes (Z. noltii) to a community dominated by green macroalgae. Through time, concomitant changes at other trophic levels will most probably give origin to a new trophic structure. Moreover, river management emerged as a key question in establishing scenarios in order to determine secondary effects in eutrophied systems. Results suggest that a more conservative river management may be used as a powerful tool to remedy affected areas, including the implementation of ecological engineering principles in different possible management practices. The recent biological changes in the Mondego Estuarine Ecosystem were found to comply with the framework of the theories considered, while both Exergy-based indices were able to capture the state of the system and distinguish between different scenarios.
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short and long term effects of eutrophication on the secondary production of an intertidal macrobenthic community
Marine Biology, 2003Co-Authors: M Dolbeth, M A Pardal, Ana I Lillebo, Ulisses Miranda Azeiteiro, Joao Carlos MarquesAbstract:Secondary production of a macrobenthic community at an intertidal mudflat was estimated for 33 successive months. Sampling was carried out along a eutrophication gradient, including non-eutrophied Zostera meadows, an intermediate muddy area, and a strongly eutrophied sand-muddy flat, where macroalgal blooms of Enteromorpha spp. usually occur. The Zostera meadows were always the most productive habitat (145–225 g ash-free dry weight m−2 year−1). In the short term, the macroalgal bloom benefited the total Estuarine production by enhancing the annual production in the eutrophied area. Nevertheless, our results show that this increase was short lived and in no way sufficient to match the production in the Zostera meadows. In the long term, the present study provides evidence that the disappearance of macrophyte beds, as a result of ongoing eutrophication, constitutes a major threat to the sustainability of the Estuarine Ecosystem.
Ana Ligia Primo - One of the best experts on this subject based on the ideXlab platform.
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spatial distribution and seasonal patterns of the siphonophores muggiaea atlantica and muggiaea kochii in a temperate Estuarine Ecosystem
Estuarine Coastal and Shelf Science, 2019Co-Authors: Mariaelena Dambrosio, M A Pardal, Ana Ligia Primo, Filipe Martinho, Elena Guerrero, Sonia Cotrim MarquesAbstract:Abstract This study analysed the distribution and abundance of both polygastric (asexual) and gonophores of the calycophoran siphonophores Muggiaea atlantica and Muggiaea kochii in the Mondego estuary (Portugal), as well as the influence of local environment and prey availability on the observed patterns. Samples were collected in three different zones of the estuary, from December 2013 to November 2015. In general, both species nectophores and total gonophores followed a similar trend, with higher abundances during spring-summer periods and increased densities in the downstream areas of the estuary, where the marine influence is stronger. Inter-annual differences occurred mainly for M. atlantica nectophores, which showed higher abundances in 2015, particularly in the upstream areas. Both species displayed a shift in the annual peak abundance, from bimodal in 2014 to unimodal in 2015. Patterns observed were not only strongly related with an increase of the marine influence in the estuary, but also with the presence of zooplanktonic prey, such as cirripede cypris, calanoid nauplius, Poecilostomatoida, and copepodites of Cyclopoida. This study represents a step towards a better knowledge of the biology and ecology of siphonophores.
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predicting zooplankton response to environmental changes in a temperate Estuarine Ecosystem
Marine Biology, 2008Co-Authors: Sonia Cotrim Marques, Ulisses Miranda Azeiteiro, Sergio Leandro, Henrique Queiroga, Ana Ligia Primo, Filipe Martinho, Ivan Viegas, Miguel ângelo PardalAbstract:A 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.
Filipe Martinho - One of the best experts on this subject based on the ideXlab platform.
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spatial distribution and seasonal patterns of the siphonophores muggiaea atlantica and muggiaea kochii in a temperate Estuarine Ecosystem
Estuarine Coastal and Shelf Science, 2019Co-Authors: Mariaelena Dambrosio, M A Pardal, Ana Ligia Primo, Filipe Martinho, Elena Guerrero, Sonia Cotrim MarquesAbstract:Abstract This study analysed the distribution and abundance of both polygastric (asexual) and gonophores of the calycophoran siphonophores Muggiaea atlantica and Muggiaea kochii in the Mondego estuary (Portugal), as well as the influence of local environment and prey availability on the observed patterns. Samples were collected in three different zones of the estuary, from December 2013 to November 2015. In general, both species nectophores and total gonophores followed a similar trend, with higher abundances during spring-summer periods and increased densities in the downstream areas of the estuary, where the marine influence is stronger. Inter-annual differences occurred mainly for M. atlantica nectophores, which showed higher abundances in 2015, particularly in the upstream areas. Both species displayed a shift in the annual peak abundance, from bimodal in 2014 to unimodal in 2015. Patterns observed were not only strongly related with an increase of the marine influence in the estuary, but also with the presence of zooplanktonic prey, such as cirripede cypris, calanoid nauplius, Poecilostomatoida, and copepodites of Cyclopoida. This study represents a step towards a better knowledge of the biology and ecology of siphonophores.
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predicting zooplankton response to environmental changes in a temperate Estuarine Ecosystem
Marine Biology, 2008Co-Authors: Sonia Cotrim Marques, Ulisses Miranda Azeiteiro, Sergio Leandro, Henrique Queiroga, Ana Ligia Primo, Filipe Martinho, Ivan Viegas, Miguel ângelo PardalAbstract:A 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.