68 research outputs found

    Impact of coastal engineering on the water quality of the Ria Formosa Lagoon, Portugal

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    The Ria Formosa is a coastal lagoon in southern Portugal. It is a Ramsar and Natura 2000 site and supports important resources such as fisheries, aquaculture and tourism. Human impacts on the Ria Formosa include urbanization, intensive agriculture, aquaculture, and coastal engineering. In this rare, long-term study of a coastal lagoon, the effects of changes in coastal zone management are documented. Data from studies over 12 years are compared to follow the impact of coastal engineering on the water quality of the lagoon. The studies are: • Prior to the opening of the INDIA inlet • Following the opening of the inlet (prior to the operation of the sewage treatment plant) • After the start of the sewage treatment plant operation Recent modifications to the lagoon appear to have improved the water quality of the western lagoon with respect to dissolved oxygen percentage saturation

    Using remote sensing as a support to the implementation of the European Marine Strategy Framework Directive in SW Portugal

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    The exclusive economic zones (EEZ) of coastal countries are coming under increasing pressure from various economic sectors such as fishing, aquaculture, shipping and energy production. In Europe, there is a policy to expand the maritime economic sector without damaging the environment by ensuring that these activities comply with legally binding Directives, such as the Marine Strategy Framework Directive (MSFD). However, monitoring an extensive maritime area is a logistical and economic challenge. Remote sensing is considered one of the most cost effective, methods for providing the spatial and temporal environmental data that will be necessary for the effective implementation of the MSFD. However, there is still a concern about the uncertainties associated with remote sensed products. This study has tested how a specific satellite product can contribute to the monitoring of a MSFD Descriptor for "good environmental status" (GES). The results show that the quality of the remote sensing product Algal Pigment Index 1 (API 1) from the MEdium Resolution Imaging Spectrometer (MERIS) sensor of the European Space Agency for ocean colour products can be effectively validated with in situ data from three stations off the SW Iberian Peninsula. The validation results show good agreement between the MERIS API 1 and the in situ data for the two more offshore stations, with a higher coefficient of determination (R-2) of 0.79, and with lower uncertainties for the average relative percentage difference (RPD) of 24.6% and 27.9% and a root mean square error (RMSE) of 0.40 and 0.38 for Stations B and C, respectively. Near to the coast, Station A has the lowest R-2 of 0.63 and the highest uncertainties with an RPD of 112.9% and a RMSE of 1.00. It is also the station most affected by adjacency effects from the land: when the Improved Contrast between Ocean and Land processor (ICOL) is applied the R-2 increases to 0.77 and there is a 30% reduction in the uncertainties estimated by RPD. The MERIS API 1 product decreases from inshore to offshore, with higher values occurring mainly between early spring and the end of the summer, and with lower values during winter. By using the satellite images for API 1, it is possible to detect and track the development of algal blooms in coastal and marine waters, demonstrating the usefulness of remote sensing for supporting the implementation of the MSFD with respect to Descriptor 5: Eutrophication. It is probable that remote sensing will also prove to be useful for monitoring other Descriptors of the MSFD.EU (European Space Agency) [308392, 21464/08/1-0, 607325]; Portuguese FCT [FRH/BD/78354/2011, SFRH/BD/78356/2011]; Horizon 2020 AquaSpace [633476]info:eu-repo/semantics/publishedVersio

    The application of remote sensing for monitoring the Ria Formosa: the sentinel missions

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    The Ria Formosa (RF) coastal lagoon (Figure 10.1) is composed of a group of two peninsulas, five barrier islands that are separated by 6 inlets, which enable the exchange of water, sediments, nutrients and other chemicals between the lagoon and the ocean. The RF incorporates important habitats, such as salt marshes, dunes, lagoon marshes and intertidal zones. The RF supports a wide range of human activities, including economic sectors such as fisheries and aquaculture, tourism, ecotourism, navigation and port activities, salt and sediment extraction (Newton et al., 2014). Essentially, these economic activities depend on the ecosystem services of the lagoon including food provisioning (mainly shellfish and fish), hydrological balance, climate regulation, flood protection, water purification, oxygen production, primary and secondary production, recreation and ecotourism (Newton et al., 2018). Due to its environmental importance, the RF has been a Natural Park since 1987 and is part of the Natura 2000 network. The wetland area is specifically protected under the Ramsar convention.info:eu-repo/semantics/publishedVersio

    Monitoring of oxygen condition in the Ria Formosa coastal lagoon, Portugal

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    Dissolved oxygen (DO) is one of the most important environmental variables of water quality, especially for marine life. Consequently, oxygen is one of the Chemical Quality Elements required for the implementation of European Union Water Framework Directive. This study uses the example of the Ria Formosa, a meso-tidal lagoon on the south coast of Portugal to demonstrate how monitoring of water quality for coastal waters must be well designed to identify symptoms of episodic hypoxia. New data from the western end of the Ria Formosa were compared to values in a database of historical data and in the published literature to identify long-term trends. The dissolved oxygen concentration values in the database and in the literature were generally higher than those found in this study, where episodic hypoxia was observed during the summer. Analysis of the database showed that the discrepancy was probably related with the time and the sites where the samples had been collected, rather than a long-term trend. The most problematic situations were within the inner lagoon near the city of Faro, where episodic hypoxia (<2 mg dm3 DO) occurred regularly in the early morning. These results emphasise the need for a balanced sampling strategy for oxygen monitoring which includes all periods of the day and night, as well as a representative range of sites throughout the lagoon. Such a strategy would provide adequate data to apply management measures to reduce the risk of more persistent hypoxia that would impact on the ecological, important natural resource. economic and leisure uses of this Important natural resource

    Role of microbes in the Ria Formosa lagoon

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    With the development of epifluorescence microscopy and sensitive radioisotope techniques, high abundance and activity of microorganisms was observed in marine waters since 1970s and 1980s. These observations resulted in a new concept of rapid turn-over and recycling of organic matter through a ‘microbial loop’ (Azam et al., 1983; Azam, 1998). Figure 5.1 illustrates fluxes of material through the marine microbial loop. Main processes are C fixation by photosynthetic microorganisms (prokaryotic and eukaryotic) with exudation losses of Dissolved Organic Matter (DOM), which is incorporated by heterotrophic bacteria. Phagotrophic protists in turn graze both autotrophs and bacteria producing ‘sloppy feeding’ loss of DOM, which returns to the loop. DOM is remineralized by all microorganisms into Dissolved Inorganic Nutrients (DIN), which are taken up by autotrophic and heterotrophic microorganisms.EU contract EVK3-CT1999-00002info:eu-repo/semantics/publishedVersio

    An Analysis of the Global Applicability of Ostrom’s Design Principles to Diagnose the Functionality of Common-Pool Resource Institutions

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    There are a number of gaps in reviews relating Ostrom’s design principles (DPs) to common-pool resource (CPR) institutions. These include the geographical distribution of CPRs, the performance of young CPRs relative to the DPs, and the relationship between robustness and success in adherence to the DPs. to This research aims to: (i) explicitly analyze the geographical distribution of the case studies that have used the DPs, (ii) explore the relationship between the DPs and young CPR institutions, (iii) examine the relationship between robustness and success of CPR institutions based on the DPs, and (iv) identify additional factors contributing to the performance of CPR institutions. In relation to Ostrom’s DPs, the CPRs under review involve management only by the community, co-management between the community and the state, and co-management between the community and non-governmental organizations. The results show that: DPs have been applied in all the inhabited continents; the expression of the DPs is affected by the geographical settings; the DPs do not conclusively diagnose the functionality of young and viable CPR institutions, whereas they may do so for either the short-lived (failed) or the long-lasting institutions; the relationship between robustness and success appears weak; and there are additional factors that contribute to the outcomes of CPR managemen

    MERIS phytoplankton time series products from the SW Iberian Peninsula (Sagres) using seasonal-trend decomposition based on loess

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    The European Space Agency has acquired 10 years of data on the temporal and spatial distribution of phytoplankton biomass from the MEdium Resolution Imaging Spectrometer (MERIS) sensor for ocean color. The phytoplankton biomass was estimated with the MERIS product Algal Pigment Index 1 (API 1). Seasonal-Trend decomposition of time series based on Loess (STL) identified the temporal variability of the dynamical features in the MERIS products for water leaving reflectance ((w)()) and API 1. The advantages of STL is that it can identify seasonal components changing over time, it is responsive to nonlinear trends, and it is robust in the presence of outliers. One of the novelties in this study is the development and the implementation of an automatic procedure, stl.fit(), that searches the best data modeling by varying the values of the smoothing parameters, and by selecting the model with the lowest error measure. This procedure was applied to 10 years of monthly time series from Sagres in the Southwestern Iberian Peninsula at three Stations, 2, 10 and 18 km from the shore. Decomposing the MERIS products into seasonal, trend and irregular components with stl.fit(), the (w)() indicated dominance of the seasonal and irregular components while API 1 was mainly dominated by the seasonal component, with an increasing effect from inshore to offshore. A comparison of the seasonal components between the (w)() and the API 1 product, showed that the variations decrease along this time period due to the changes in phytoplankton functional types. Furthermore, inter-annual seasonal variation for API 1 showed the influence of upwelling events and in which month of the year these occur at each of the three Sagres stations. The stl.fit() is a good tool for any remote sensing study of time series, particularly those addressing inter-annual variations. This procedure will be made available in R software

    The marine plastic litter issue: a social-economic analysis

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    The issue of marine plastic litter pollution is multifaceted, cross-sectoral, and ongoing in the absence of appropriate management measures. This study analysed the issue of marine plastic litter pollution in the context of the Descriptor 10 of the Marine Strategy Framework Directive and Good Environmental Status of the oceans and seas. The Driver-Pressure-State-Impact-Response (DPSIR) framework was used to assess the causes, e ects, and management measures to changes in the marine environment resulting from marine plastics pollution. We noted that less than 10 peer-reviewed publications have applied the Driver-Pressure-State-Impact-Response (DPSIR) model to the issue of marine plastics pollution. Some basic needs such as food security, movement of goods and services, and shelter are also some of the major drivers of marine plastic pollution. The use of plastics is linked to multiple economic sectors (fisheries, agriculture, transport, packaging, construction) and other human activities. A significant amount of the resulting pressures came from the economic sectors for packaging and construction. State changes occurred at the environmental (contamination and bioaccumulation), ecosystem (ingestion of plastics, ghost fishing) and ecosystem service levels (supply of sea food, salt and cultural benefits), with possible loss of jobs and income being some of the observed impacts on human welfare. Responses as management measures, which are tailored to meet each component of the DPSIR framework, were identified. These included policies, regulations, technological advancement and behavioural change. The research acknowledges the issue of marine plastics pollution as a global environmental problem and recommends a trans-disciplinary approach, involving all types of stakeholders. Future research and analysis applying the DPSIR framework will be useful to provide the information necessary for the e ective, adaptive management of litter pollution by marine plastics.PLASTICSEA- Impact of Microplastics in the Ocean, Sea Salt and Aquaculture FA-06-2017-0046; FCT: UI/MAR/00350/2020:info:eu-repo/semantics/publishedVersio

    Evaluation of eutrophication in the Ria Formosa coastal lagoon, Portugal

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    The Ria Formosa is a shallow mesotidal lagoon on the south coast of Portugal, with natural biogeochemical cycles essentially regulated by tidal exchanges at the seawater boundaries and at the sediment interface. Existing data on nutrients in the water column and the sediment, together with chlorophyll a and oxygen saturation in the water column,compared using different models for assessing eutrophication. The European Environmental Agency criteria are based on the comparison of nutrient concentrations which indicate that the situation in the Ria Formosa is ‘‘poor’’ to ‘‘bad’’. In contrast, the United States Estuarine Eutrophication Assessment is based on symptoms, including high chlorophyll a and low oxygen saturation, which indicate that the Ria Formosa is near pristine. Despite these contradictions, a preliminary assessment by Driving forces, Pressures, State, Impact, Reponses(DPSIR) of eutrophication demonstrate the potential for episodic eutrophic conditions from treated and untreated domestic effluent as well as from non-point source agricultural run off. Sediments are also an important source of nutrients in the lagoon, but their contribution to potential eutrophic conditions is unknown

    Social-environmental analysis for the management of coastal lagoons in North Africa

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    This study provides an overview of 11 lagoons in North Africa, from the Atlantic to the Eastern Mediterranean. Lagoons are complex, transitional, coastal zones providing valuable ecosystem services that contribute to the welfare of the human population. The main economic sectors in the lagoons included fishing, shellfish harvesting, and salt and sand extraction, as well as maritime transport. Economic sectors in the areas around the lagoons and in the watershed included agriculture, tourism, recreation, industrial, and urban development. Changes were also identified in land use from reclamation, changes in hydrology, changes in sedimentology from damming, inlet modifications, and coastal engineering. The human activities in and around the lagoons exert multiple pressures on these ecosystems and result in changes in the environment, affecting salinity, dissolved oxygen, and erosion; changes in the ecology, such as loss of biodiversity; and changes in the delivery of valuable ecosystem services. Loss of ecosystem services such as coastal protection and seafood affect human populations that live around the lagoons and depend on them for their livelihood. Adaptive management frameworks for social–ecological systems provide options that support decision makers with sciencebased knowledge to deliver sustainable development for ecosystems. The framework used to support the decision makers for environmental management of these 11 lagoons is Drivers–Activities–Pressures–State Change–Impact (on Welfare)–Responses (as Measures).info:eu-repo/semantics/publishedVersio
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