Benthic meiofauna as indicator of ecological changes in estuarine ecosystems: The use of nematodes in ecological quality assessment

a b s t r a c t Estuarine meiofauna communities have been only recently considered to be good indicators of ecological quality, exhibiting several advantages over macrofauna, such as their small size, high abundance, rapid generation times and absence of a planktonic phase. In estuaries we must account not only for a great natural variability along the estuarine gradient (e.g. sediment type and dynamics, oxygen availability, temperature and flow speed) but also for the existence of anthropogenic pressures (e.g. high local population density, presence of harbors and dredging activities). Spatial and temporal biodiversity patterns of meiofauna and freeliving marine nematodes were studied in the Mondego estuary (Portugal). Both taxonomic and functional approaches were applied to nematode communities in order to describe the community structure and to relate it with the environmental parameters along the estuary. At all sampling events, nematode assemblages reflected the estuarine gradient, and salinity and grain size composition were confirmed to be the main abiotic factors controlling the distribution of the assemblages. Moreover, the low temporal variability may indicate that natural variability is superimposed by the anthropogenic pressures present in some areas of the estuary. The characterization of both meiofauna and nematode assemblages highlighted the usefulness of the integration of both taxonomic and functional attributes, which must be taken into consideration when assessing the ecological status of estuaries

On the relevance of freshwater nematodes for ecological assessment in transitional waters

Nematoda is the most common group of organisms in the meiobenthic assemblages of freshwater and marine systems and, in Portugal, its distribution has been studied along the estuarine gradient of two estuaries. Nematodes are recognized as good indicators of anthropogenic impacts in aquatic ecosystems and, together with the taxonomic data, the inclusion of functional diversity can create a powerful tool, providing information on the functioning of ecosystems. Most estuarine studies do not encompass information to genus/species level of freshwater nematodes or reduce the information to family level, impoverishing thus information on diversity. The main aim of this study is to evaluate the information loss effect on the assessment of the ecological quality status of the upstream area of the Mondego estuary, caused by the non identification of freshwater nematodes– both taxonomic and functional approaches of nematode estuarine communities. Results show that nematodes assemblages reflected the salinity gradient, with increasing densities and diversity from oligohaline to euhaline areas. Freshwater nematodes contributed with a small percentage (3.5% of total density), but were very abundant in the upstream areas (0.5 – 47.4%). Without freshwater nematodes, the separation of salinity stretches was maintained (with lower distinction of the stretches) and the performance of the Index of Trophic Diversity and the Maturity Index revealed a worse condition of the ecological status of oligohaline and mesohaline stretches. This study shows that taxonomic and biologic characteristics of freshwater nematodes should be evaluated when assessing the ecological status of an estuary in order to correctly classify the uppermost sections of estuaries. Keywords: estuarine gradient, Mondego estuary, Portugal, subtidal meiobenthi

Effects of a herbicide and copper mixture on the quality of marine plankton

Pesticides and metals are often used in agriculture and are therefore often simultaneously discharged to nearby estuarine and marine areas. The effects of this organic-inorganic chemical mixture on food quality of aquatic organisms are currently unknown. In this study we test if a mixture of copper (inorganic) and the herbicide Primextra® Gold TZ (organic) affects the quality of the diatom Thalassiosira weissflogii and the copepod Acartia tonsa - two key species that fuel the local food-web. We quantified quality (i.e. energy content as food for the next trophic level) in terms of fatty acids, proteins and thiobarbituric acid reacting substances. We found non-additive effects (positive and negative) of the metal-herbicide mixture on the diatom and copepod species. In general, nutritionally important biochemical parameters of Acartia tonsa were most sensitive to the chemical stressors

Patterns of variation in the biochemical composition of Mesopodopsis slabberi (Van Beneden, 1861) (Crustacea: Mysidacea)

In order to assess the patterns of variation in the biochemical composition of Mesopodopsis slabberi (Van Beneden, 1861) in a temperate estuary, we determined the protein, carbohydrate, chitin and lipid contents of freshly caught immature individuals (juveniles), adult males, and adult females during two annual cycles. Statistical analysis (anova) revealed significant differences in the biochemical components between months and development stages for the months analysed. All of the biochemical components showed significant differences between months. Environmental and trophic conditions were the main processes determining seasonal patterns of variation in biochemical composition. The results of complementary experiments carried out to estimate the effects of starvation on biochemical composition showed that the process of starvation consumed mostly carbohydrates, and also that these compounds, together with lipids, were the most affected during the refeeding period. Our findings also indicate that all body reserves were almost fully replenished during refeeding, except for carbohydrates and lipids in adult females and immature individuals (juveniles) and protein content in immature individuals (juveniles). These results indicate that responses to fasting in M. slabberi may be dependent on individual development stages, an observation that is corroborated by the significant differences in the biochemical components observed between development stages for the months analysed. Reproduction was also found to influence patterns of variation in biochemical composition.Para evaluar los modelos de variación de la composición bioquímica de Mesopodopsis slabberi (Van Beneden, 1861) en un estuario templado, determinamos los contenidos en proteínas, hidratos de carbono, quitina y lípidos de individuos inmaduros (juveniles) recién cogidos, y de machos y hembras adultos, durante dos ciclos anuales. Los análisis estadísticos (anova) revelaron, para los meses analizados, diferencias significativas en las composiciones bioquímicas entre los meses y los estados de desarrollo. Todos los componentes bioquímicos mostraron diferencias significativas entre meses. Los factores ambientales y tróficos fueron los principales procesos que determinaron los modelos estacionales de variación en la composición bioquímica. Los resultados de los experimentos complementarios, realizados para determinar los efectos de la inanición sobre la composición bioquímica, pusieron de manifiesto que los procesos de inanición consumen, fundamentalmente, hidratos de carbono, y, también, que estos compuestos, junto con los lípidos, son los más afectados durante el periodo de vuelta a la alimentación. Nuestros descubrimientos indicaron también que todas las reservas corporales son casi completamente repuestas durante la vuelta a la alimentación, excepto los hidratos de carbono y los lípidos en las hembras adultas y en los inmaduros (juveniles), y el contenido en proteínas en los juveniles. Estos resultados indican que las respuestas al ayuno de M. slabberi podrían depender del estado de desarrollo individual, observación que es corroborada por las diferencias significativas observadas, en los componentes bioquímicos y para los meses analizados, entre los distintos estados de desarrollo. Se encontró también que la reproducción tenía influencia sobre los modelos de variación de la composición bioquímica.Instituto Español de Oceanografí

Descolonizando Tiempo, Espacio y Conocimiento: El pueblo Kamëntšá en la encrucijada del patrimonio cultural

The dissertation is focused on three interrelated aspects: 1) the development of a decolonial theoretical framework and collaborative research methodology with the Kamëntšá people centred on the respect for Kamëntšá ethics, principles and social norms, and the consequent reconstruction, revitalization and dignification of Kamëntšá knowledge, arts, spirituality and notions of time and space; 2) the history and colonization processes of the Kamëntšá people and Uaman Tabanok, its ancestral lands, with a specific emphasis on the work of the Capuchin missionaries, particularly their concept of enculturation and how it transformed and resignified Kamëntšá culture and religion using its own arts, narratives and rituals which were in harmony with Christianity; and 3) the concept of “cultural heritage” and the role of academic disciplines, research practices, government institutions and cultural policies in the perpetuation of colonialism through the appropriation, interpretation, control and resignification of the objects, monuments and cultures of Indigenous peoples, and their consequent contribution to maintaining inequality, racism and historical social injustices.Gerda Henkel Foundation Portuguese Foundation for Science and Technology (FCT) German Academic Exchange Service (DAAD) COLING Project - EU Horizon 2020 program under the Marie Skłodowska-Curie Grant Agreement No 778384Heritage of Indigenous People

Transition to Product Service Systems: methodology based on scenarios identification, modelling and evaluation

Part 4: Transition Towards Product-Service SystemsInternational audienceThe paper proposes a methodology to support the organisational shift towards product Services Systems. Its backbone is the evaluation of economic impact of such a shift. However, in order to efficiently accommodate organisational changes and include company specificities, other steps are required prior to evaluation. These are context analysis, scenarios identification and modelling. The novelty of the paper lies in (i) including organisational changes in the evaluation and (ii) managing the contextualization to company specificities

On the relevance of freshwater nematodes for ecological assessment in transitional waters

Nematoda is the most common group of organisms in the meiobenthic assemblages of freshwater and marine systems and, in Portugal, its distribution has been studied along the estuarine gradient of two estuaries. Nematodes are recognized as good indicators of anthropogenic impacts in aquatic ecosystems and, together with the taxonomic data, the inclusion of functional diversity can create a powerful tool, providing information on the functioning of ecosystems. Most estuarine studies do not encompass information to genus/species level of freshwater nematodes or reduce the information to family level, impoverishing thus information on diversity. The main aim of this study is to evaluate the information loss effect on the assessment of the ecological quality status of the upstream area of the Mondego estuary, caused by the non identification of freshwater nematodes– both taxonomic and functional approaches of nematode estuarine communities. Results show that nematodes assemblages reflected the salinity gradient, with increasing densities and diversity from oligohaline to euhaline areas. Freshwater nematodes contributed with a small percentage (3.5% of total density), but were very abundant in the upstream areas (0.5 – 47.4%). Without freshwater nematodes, the separation of salinity stretches was maintained (with lower distinction of the stretches) and the performance of the Index of Trophic Diversity and the Maturity Index revealed a worse condition of the ecological status of oligohaline and mesohaline stretches. This study shows that taxonomic and biologic characteristics of freshwater nematodes should be evaluated when assessing the ecological status of an estuary in order to correctly classify the uppermost sections of estuaries