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Fabrice Martin-laurent - One of the best experts on this subject based on the ideXlab platform.
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Benthic microbial community adaptation to pesticide: a promising biological Indicator to assess Ecological recovery following a decrease in pesticide contamination
2015Co-Authors: Stéphane Pesce, Christelle Margoum, Nadine Rouard, Arnaud Foulquier, Fabrice Martin-laurentAbstract:In lotic ecosystems, benthic microbial assemblages are considered as useful potential Indicators of Ecological status because they integrate the effects of multiple disturbances and have a strong capacity to adapt to stressors. Chronic pesticides exposure can thus induce adaptation processes in benthic microbial communities, leading to an increase in their capacities to tolerate and/or degrade these toxicants. It suggests that the study of microbial adaptation can represent a powerful Ecological Indicator for monitoring pesticide contamination and assessing associated Ecological effects. Accordingly we evaluated the use of i) freshwater sediment biodegradation potential and ii) periphytic biofilms tolerance capacities, as microbial Indicators for monitoring Ecological recovery following a decrease in pesticide exposure. For this purpose, a 3.5-year case study (2008–2011) was conducted in a French small stream long exposed to high concentrations of the herbicide diuron. Our results showed that the ban on diuron in December 2008 resulted in a progressive decrease in its concentrations in the river, leading to a fall in sediment diuron-mineralizing capacities. The PICT approach also revealed a decrease in the capacity of periphytic phototrophic communities to tolerate this herbicide. These results open prospects for developing a new class of Ecological Indicator based on microbial adaptation capacities.
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Freshwater sediment pesticide biodegradation potential as an Ecological Indicator of microbial recovery following a decrease in chronic pesticide exposure
2014Co-Authors: Stéphane Pesce, Christelle Margoum, Nadine Rouard, Arnaud Foulquier, Fabrice Martin-laurentAbstract:Water resources and aquatic ecosystems are an essential concern of any policy for sustainable development. In the context of the European Water Framework Directive, which aims to achieve good chemical and Ecological status of waters, the herbicide diuron was banned in France in December 2008. In lotic ecosystems, benthic microbial assemblages are considered as useful potential Indicators of Ecological status because they integrate the effects of multiple anthropogenic disturbances and have strong capacities to adapt to novel environmental conditions. Field studies have thus revealed that in situ diuron exposure can induce microbial adaptation leading to an increase in diuron biodegradation potential of sediment microbial communities. It suggests that microbial biodegradation capacities can represent a powerful Ecological Indicator for monitoring spatio-temporal variations in pesticide contamination and evaluating associated Ecological effects. The aim of this study was thus to evaluate the use of freshwater sediment biodegradation potential as an Ecological Indicator for monitoring microbial recovery following a decrease in chronic pesticide exposure. For this purpose, a four-year case study (2008–2011) was conducted in a small stream (Morcille river) long exposed to high diuron concentrations, increasing from upstream to downstream. Our results show that the ban on diuron resulted in a progressive decrease in its concentrations in the Morcille river over the survey period. The decrease in the level of chronic diuron exposure in the river caused a fall in sediment diuron-mineralizing capacities, assessed by radiorespirometry using [ring-U-14C] diuron. It thus revealed a corresponding recovery of microbial communities, showing that the use of freshwater sediment biodegradation potential may be useful for assessing microbial recovery after a decrease in chronic exposure to pollutants, opening prospects for developing a new class of Ecological Indicator to monitor the recovery of biological quality of water resources.
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Freshwater sediment pesticide biodegradation potential as an Ecological Indicator of microbial recovery following a decrease in chronic pesticide exposure: A case study with the herbicide diuron
Ecological Indicators, 2013Co-Authors: Stéphane Pesce, Christelle Margoum, Nadine Rouard, Arnaud Foulquier, Fabrice Martin-laurentAbstract:The aim of this study was to evaluate the use of freshwater sediment biodegradation potential as an Ecological Indicator for monitoring microbial recovery following a decrease in chronic pesticide exposure. For this purpose, a four-year case study (2008–2011) was conducted in a small stream (Morcille river) long exposed to high diuron concentrations, increasing from upstream to downstream. Our results show that the ban on diuron in December 2008 resulted in a progressive decrease in its concentrations in the Morcille river over the survey period. However, diuron remained present in the water three years after the ban. The spatio-temporal variations in the sediment biodegradation potential were assessed by radiorespirometry using [ring-U-14C] diuron to estimate diuron mineralization potentials. Between autumn 2008 and autumn 2011, mean diuron mineralization percentage after 15 weeks of incubation decreased by 65% downstream and by 82% in the intermediate sector, and mean 10% diuron dissipation time values increased between 143% (downstream) and 210% (intermediate). Thus the decrease in the level of chronic diuron exposure in the river also caused a fall in sediment diuron-mineralizing capacities, revealing a corresponding recovery of microbial communities. Our results show that the use of freshwater sediment biodegradation potential may be useful for assessing microbial recovery after a decrease in chronic exposure to pollutants, opening prospects for developing a new class of Ecological Indicator to monitor the recovery of biological quality of water resources. In this way, the use of molecular approaches based on direct extraction of nucleic acids from environmental matrices and their subsequent analysis by PCR-based approaches to quantify the abundance of pesticide-degrading communities could represent a promising alternative.
Alexander J. Kempers - One of the best experts on this subject based on the ideXlab platform.
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Tanacetum vulgare as a BioIndicator of Trace-Metal Contamination: A Study of a Naturally Colonized Open-Pit Lignite Mine
Archives of Environmental Contamination and Toxicology, 2013Co-Authors: Mateusz Jasion, Aleksandra Samecka-cymerman, Krzysztof Kolon, Alexander J. KempersAbstract:We investigated the possibility of use of Tanacetum vulgare (tansy) as an Ecological Indicator of metal concentration in a naturally colonized open-pit lignite mine in Bełchatów (Poland). Tanacetum vulgare is the only species growing abundantly and spontaneously in the lignite mine waste dumps. Metal concentrations in roots, stems, leaves, flowers, and soil were measured in dump sites differing in type and time of reclamation and therefore differing in pollution levels. Tanacetum vulgare appeared to be an accumulator of chromium and iron in roots, whereas highest concentrations of manganese and zinc were found in leaves. A high bioaccumulation factor for cadmium (Cd) was observed in dumps and control sites, indicating that even small amounts of Cd in the environment may result in significant uptake by the plant. The lowest concentrations of metals were found in plants from sites situated on dumps reclaimed with argillaceous limestone.
Joao Carlos Marques - One of the best experts on this subject based on the ideXlab platform.
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ascendency as Ecological Indicator for environmental quality assessment at the ecosystem level a case study
Hydrobiologia, 2006Co-Authors: Joana Patricio, Robert E Ulanowicz, M A Pardal, Joao Carlos MarquesAbstract:Previous studies have shown that when an ecosystem consists of many interacting components it becomes impossible to understand how it functions by focussing only on individual relationships. Alternatively, one can attempt to quantify system behaviour as a whole by developing Ecological Indicators that combine numerous environmental factors into a single value. One such holistic measure, called the system ‘ascendency’, arises from the analysis of networks of trophic exchanges. It deals with the joint quantification of overall system activity with the organisation of the component processes and can be used specifically to identify the occurrence of eutrophication. System ascendency analyses were applied to data over a gradient of eutrophication in a well documented small temperate intertidal estuary. Three areas were compared along the gradient, respectively, non eutrophic, intermediate eutrophic, and strongly eutrophic. Values of other measures related to the ascendency, such as the total system throughput, development capacity, and average mutual information, as well as the ascendency itself, were clearly higher in the non-eutrophic area. When the whole-system properties of the three areas were compared, however, the values associated with the intermediate eutrophic area turned out to be the lowest, which possibly could be attributed to the unstable nature of this area. The current study provided an example of how the measures arising out of network analysis might lead to an improved understanding of the system functioning and of the eutrophication process itself.
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application of the exergy index as Ecological Indicator of organically enrichment areas in the mar menor lagoon south eastern spain
Energy, 2005Co-Authors: F Salas, Concepcion Marcos, Angel Perezruzafa, Joao Carlos MarquesAbstract:The increase of stress induced changes in marine environments caused by different types of marine pollution made necessary the search for Indicators that assist in assessing pollution effects at the community level. The main goals, with a view to an effective management, are the early detection and evaluation of environmental responses to pollution and to avoid or mitigate negative impacts that different uses may generate. Exergy has been considered as a promising Indicator of ecosystem integrity, acquiring a considerable interest in the context of systems ecology. In this research we have tested the capability of exergy (both the exergy index and specific exergy) alongside other diversity indices (Shannon and Margalef indices) of distinguishing organically enriched areas in a Mediterranean coastal lagoon (El Mar Menor). Results show that the exergy index and specific exergy were able to give useful information on community structure, although they were not capable of distinguishing high and poor organically enriched areas or affected by any other type of pollution. Diversity indices were more sensitive to organic pollution. We may say that the exergy and specific exergy are still not applicable as the only Ecological Indicators in a generalized way in the field of environmental management. Therefore, they still require further application in a wider range of geographical areas and in different conditions in order to study more widely the properties of exergy as an Ecological Indicator.
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ascendency as an Ecological Indicator a case study of estuarine pulse eutrophication
Estuarine Coastal and Shelf Science, 2004Co-Authors: Joana Patricio, Robert E Ulanowicz, M A Pardal, Joao Carlos MarquesAbstract:Increasingly, management agencies require that the remediation of eutrophic waters be addressed at the level of the whole ecosystem. One whole-system approach to quantify ecosystems is called Ecological network analysis. Ascendency theory, the branch of the field that deals with the quantification of whole-system status, specifically addresses the definition of eutrophication. This definition has been applied to data taken over a gradient of eutrophication. Three separate areas were observed: a non-eutrophic area (with Zostera noltii meadows), an intermediate eutrophic area (Z. noltii absent and macroalgae abundant at times) and a strongly eutrophic area (where Enteromorpha spp. blooms occur with regularity). Pulse eutrophication was considered as the major driving force behind a gradual shift in primary producers from a community dominated by rooted macrophytes (Z. noltii) to a community dominated by green macroalgae. The measures associated with the intermediate eutrophic region turned out not to be intermediate to those at the gradient extremes. The most likely explanation appears to be the highly unstable nature of this area. Conditions along the spatial gradient are discussed as representing various stages in the temporal evolution of the system, and analysed in the framework of the Intermediate Disturbance Hypothesis, Bifurcation, Chaos, and Catastrophe theories.
Stéphane Pesce - One of the best experts on this subject based on the ideXlab platform.
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Benthic microbial community adaptation to pesticide: a promising biological Indicator to assess Ecological recovery following a decrease in pesticide contamination
2015Co-Authors: Stéphane Pesce, Christelle Margoum, Nadine Rouard, Arnaud Foulquier, Fabrice Martin-laurentAbstract:In lotic ecosystems, benthic microbial assemblages are considered as useful potential Indicators of Ecological status because they integrate the effects of multiple disturbances and have a strong capacity to adapt to stressors. Chronic pesticides exposure can thus induce adaptation processes in benthic microbial communities, leading to an increase in their capacities to tolerate and/or degrade these toxicants. It suggests that the study of microbial adaptation can represent a powerful Ecological Indicator for monitoring pesticide contamination and assessing associated Ecological effects. Accordingly we evaluated the use of i) freshwater sediment biodegradation potential and ii) periphytic biofilms tolerance capacities, as microbial Indicators for monitoring Ecological recovery following a decrease in pesticide exposure. For this purpose, a 3.5-year case study (2008–2011) was conducted in a French small stream long exposed to high concentrations of the herbicide diuron. Our results showed that the ban on diuron in December 2008 resulted in a progressive decrease in its concentrations in the river, leading to a fall in sediment diuron-mineralizing capacities. The PICT approach also revealed a decrease in the capacity of periphytic phototrophic communities to tolerate this herbicide. These results open prospects for developing a new class of Ecological Indicator based on microbial adaptation capacities.
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Freshwater sediment pesticide biodegradation potential as an Ecological Indicator of microbial recovery following a decrease in chronic pesticide exposure
2014Co-Authors: Stéphane Pesce, Christelle Margoum, Nadine Rouard, Arnaud Foulquier, Fabrice Martin-laurentAbstract:Water resources and aquatic ecosystems are an essential concern of any policy for sustainable development. In the context of the European Water Framework Directive, which aims to achieve good chemical and Ecological status of waters, the herbicide diuron was banned in France in December 2008. In lotic ecosystems, benthic microbial assemblages are considered as useful potential Indicators of Ecological status because they integrate the effects of multiple anthropogenic disturbances and have strong capacities to adapt to novel environmental conditions. Field studies have thus revealed that in situ diuron exposure can induce microbial adaptation leading to an increase in diuron biodegradation potential of sediment microbial communities. It suggests that microbial biodegradation capacities can represent a powerful Ecological Indicator for monitoring spatio-temporal variations in pesticide contamination and evaluating associated Ecological effects. The aim of this study was thus to evaluate the use of freshwater sediment biodegradation potential as an Ecological Indicator for monitoring microbial recovery following a decrease in chronic pesticide exposure. For this purpose, a four-year case study (2008–2011) was conducted in a small stream (Morcille river) long exposed to high diuron concentrations, increasing from upstream to downstream. Our results show that the ban on diuron resulted in a progressive decrease in its concentrations in the Morcille river over the survey period. The decrease in the level of chronic diuron exposure in the river caused a fall in sediment diuron-mineralizing capacities, assessed by radiorespirometry using [ring-U-14C] diuron. It thus revealed a corresponding recovery of microbial communities, showing that the use of freshwater sediment biodegradation potential may be useful for assessing microbial recovery after a decrease in chronic exposure to pollutants, opening prospects for developing a new class of Ecological Indicator to monitor the recovery of biological quality of water resources.
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Freshwater sediment pesticide biodegradation potential as an Ecological Indicator of microbial recovery following a decrease in chronic pesticide exposure: A case study with the herbicide diuron
Ecological Indicators, 2013Co-Authors: Stéphane Pesce, Christelle Margoum, Nadine Rouard, Arnaud Foulquier, Fabrice Martin-laurentAbstract:The aim of this study was to evaluate the use of freshwater sediment biodegradation potential as an Ecological Indicator for monitoring microbial recovery following a decrease in chronic pesticide exposure. For this purpose, a four-year case study (2008–2011) was conducted in a small stream (Morcille river) long exposed to high diuron concentrations, increasing from upstream to downstream. Our results show that the ban on diuron in December 2008 resulted in a progressive decrease in its concentrations in the Morcille river over the survey period. However, diuron remained present in the water three years after the ban. The spatio-temporal variations in the sediment biodegradation potential were assessed by radiorespirometry using [ring-U-14C] diuron to estimate diuron mineralization potentials. Between autumn 2008 and autumn 2011, mean diuron mineralization percentage after 15 weeks of incubation decreased by 65% downstream and by 82% in the intermediate sector, and mean 10% diuron dissipation time values increased between 143% (downstream) and 210% (intermediate). Thus the decrease in the level of chronic diuron exposure in the river also caused a fall in sediment diuron-mineralizing capacities, revealing a corresponding recovery of microbial communities. Our results show that the use of freshwater sediment biodegradation potential may be useful for assessing microbial recovery after a decrease in chronic exposure to pollutants, opening prospects for developing a new class of Ecological Indicator to monitor the recovery of biological quality of water resources. In this way, the use of molecular approaches based on direct extraction of nucleic acids from environmental matrices and their subsequent analysis by PCR-based approaches to quantify the abundance of pesticide-degrading communities could represent a promising alternative.
Pedro Pinho - One of the best experts on this subject based on the ideXlab platform.
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tracking global change using lichen diversity towards a global scale Ecological Indicator
Methods in Ecology and Evolution, 2017Co-Authors: Paula Matos, Linda H Geiser, Amanda Hardman, Doug A Glavich, Pedro Pinho, Alice Nunes, Amadeu M V M SoaresAbstract:Summary Lichens have been used to efficiently track major drivers of global change from the local to regional scale since the beginning of the industrial revolution (sulphur dioxide) to the present (nitrogen deposition and climate change). Currently, the challenge is to universalize monitoring methodologies to compare global change drivers’ simultaneous and independent effects on ecosystems and to assess the efficacy of mitigation measures. Because two protocols are now used at a continental scale North America (US) and Europe (EU), it is timely to investigate the compatibility of the interpretation of their outcomes. For the first time, we present an analytical framework to compare the interpretation of data sets coming from these methods utilizing broadly accepted biodiversity metrics, featuring a paired data set from the US Pacific Northwest. The methodologies yielded highly similar interpretation trends between response metrics: taxonomic diversity, functional diversity and community composition shifts in response to two major drivers of global change (nitrogen deposition and climate). A framework was designed to incorporate surrogates of species richness (the most commonly used empirical trend in taxonomic diversity), shifts in species composition (compositional turnover) and metrics of functional diversity (link between community shifts to effects and ecosystem structure and functioning). These metrics are essential to more thoroughly comprehend biodiversity response to global change. Its inclusion in this framework enables future cross-continental analysis of lichen biodiversity change from North America and Europe in response to global change. Future works should focus on developing independent metrics for response to global change drivers, namely climate and pollution, taking us one step closer to a lichen-based global Ecological Indicator.
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multivariate geostatistical methods for analysis of relationships between Ecological Indicators and environmental factors at multiple spatial scales
Ecological Indicators, 2013Co-Authors: Manuel Ribeiro, Pedro Pinho, Esteve Llop, Cristina Branquinho, A J Sousa, Maria Joao PereiraAbstract:Abstract As all biodiversity-related variables, Ecological Indicators are influenced by environmental factors working at different spatial scales. However, assessing the relationship between environmental factors and Ecological Indicators is limited to a set of spatial scales determined a priori. This a priori assumption can hide important relationships, especially for Ecological Indicators with a complex spatial structure that can be driven, for example, by the influence of multiple pollutants with different dispersion ranges or by the influence of local and regional factors such as land-cover and climate. To relate Ecological Indicators and environmental factors without assuming a priori spatial scales of analysis, we used a Linear Model of Coregionalization. This method has been used in literature to analyze the joint distribution of biodiversity variables. Here we show that it can be used to gain insight into spatial patterns of relationships between Ecological Indicators and underlying environmental factors. We applied this method to a region of south-west Europe, relating data from land-cover, altitude and climate with an Ecological Indicator, the abundance of fruticose lichen species, known to be very sensitive to multiple environmental factors. Based on variogram analysis we identified distinct spatial scales of relationships between the Ecological Indicator and environmental factors. For each spatial scale we described relationships using Principal Component Analysis applied to the coregionalization matrices. This way we could assess how strong the relationship between each environmental factor and Ecological Indicator at each spatial scale was: at medium scales (c. 15 km) open spaces areas (a proxy for particle emissions) were more important; at larger scales (c. 45 km) open spaces, artificial areas (a proxy for gaseous pollutants) and also climate were preponderant. Thus, multivariate geostatistics provided a tool to improve knowledge on relationships between Ecological Indicators and environmental factors at multiple spatial scales without setting a priori spatial scales of analysis.
