10 research outputs found

    Temporal variation of surface chlorophyll a in the Romanian near-shore waters

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    Chlorophyll a (Chl a) dynamics in the near-shore waters of the NW Black Sea was investigated between 2002 and 2010 in the Mamaia Bay (north of Constanta, Romania) in relation to some physical-chemical parameters. Chl a ranged from values below detection limit (0.17 μg.l–1) to 76.13 μg.l–1, and showed large temporal variability (CV = 142.3%), strongly related to the Danube’s discharges, meteorological conditions, and anthropogenic pressures. Seasonally, Chl a showed a winter/early spring maximum, sometimes followed by a stronger one in April/early May, closely linked to the Danube’s higher discharges in spring. After significantly lower concentrations in late spring/early summer, Chl a exhibited its strongest maximum in summer (July-August), followed by another one in autumn (late September–October). Interannual variation of Chl a seems to be controlled by the hydrometeorological conditions in summer. Thus, the highest annual Chl a means were observed in 2006 (8.56 ± 8.35 μg.l–1) and 2010 (9.20 ± 11.72 μg.l -1), when, also, the summer Chl a concentrations were maximal due to the large riverine discharges. The lowest annual Chl a mean was observed in 2004 (4.57 ± 9.81μg.l–1), closely linked to minimal summer Chl a resulted from a strong P limitation during summertime

    An exposure-effect approach for evaluating ecosystem-wide risks from human activities

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    Ecosystem-based management (EBM) is promoted as the solution for sustainable use. An ecosystem-wide assessment methodology is therefore required. In this paper, we present an approach to assess the risk to ecosystem components from human activities common to marine and coastal ecosystems. We build on: (i) a linkage framework that describes how human activities can impact the ecosystem through pressures, and (ii) a qualitative expert judgement assessment of impact chains describing the exposure and sensitivity of ecological components to those activities. Using case study examples applied at European regional sea scale, we evaluate the risk of an adverse ecological impact from current human activities to a suite of ecological components and, once impacted, the time required for recovery to pre-impact conditions should those activities subside. Grouping impact chains by sectors, pressure type, or ecological components enabled impact risks and recovery times to be identified, supporting resource managers in their efforts to prioritize threats for management, identify most at-risk components, and generate time frames for ecosystem recovery

    Application of a data-interpolating variational analysis (DIVA) tool to physical and biogeochemical measurements covering the Black Sea

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    peer reviewedThe European project SESAME (Southern European Seas: Assessing and Modelling Ecosystem changes) is dedicated to the assessment of ecological changes in the Mediterranean and Black seas during these last decades. This assessment will be done by combining statistical analysis of available data and the development of a 3D hydrodynamical-biogeochemical model. Data available since 1960 for the Black Sea from the databases MEDAR and NATO have been completed with data provided by SESAME partners. These data sets have been analyzed using DIVA, a geostatistical analysis tool developed by the GHER laboratory of the University of Liège. The DIVA analysis relies on a finite element resolution, taking into account coastlines, sub-basins, and advection by ocean currents. DIVA analysis generates spatially interpolated fields for biogeochemical and physical variables. Outputs consist in sets of analysis as well as error fields, and colorimetric scaled maps related to several depth layers. Biogeochemical variables considered consist in measures of chlorophyll, inorganic nutrients concentration, and phytoplankton abundances; physical variables consist in temperature and salinity. These treatments of the Black sea data sets offer an overview of the global pattern of the Black sea biogeochemical structure, and its evolution through the time periods concerned by the project. The interpolated fields generated by the DIVA tool will be used to validate the outputs of the 3D hydrodynamical-biogeochemical model developed for the north-western shelf of the Black sea in the framework of SESAME

    Body size dependency of natural variability in marine ecosystems: insights on defining monitoring plans for MSFD

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    Assessing ‘natural’ variability of structural and functional components of ecosystems is a main target of MSFD, responding to the need of disentangling biological responses to anthropogenic stresses from those on which human impact is minimal. The scale and the extent of ecosystem components variability are main determinants of ecological patterns and process. Moreover, variability within ecosystems depends on both internal ecosystem dynamics and larger scale drivers and processes. Here we focus specifically on natural variability of biotic ecosystem components and ecosystem processes, which are either descriptors or parameters of relevance in the MSFD monitoring scheme. Metabolic theories have highlighted how the individual body size can be considered as a main, intrinsic driver of variation in populations and communities functional properties. Indeed, individual energetic and behaviour show body size dependent variation according to an x/4 rule. Cascading deterministic effects of individual level size-dependencies have been demonstrated on both population and community levels as well as on functional properties. In the presentation: i. We develop a conceptual analysis of the implication of body size dependencies of individual energetic and behaviour on scale and extent of natural variability in the individual, population and community parameters considered in the MSFD; ii. We present an example of phytoplankton parameter assessments with changing temporal scales of assessment in order to account for the natural variability of cell densities in the phytoplankton guilds; and iii. We infer from implications of biological parameter size dependencies on MSFD monitoring plan accounting for natural variability and derive operational proposals for adaptive monitoring plans

    Spatial and temporal extent of monitoring water column and seabed habitats indicators, based on their scales of natural variation

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    The Marine Framework Strategy Directive (MFSD, 2008/56/EC) aims for clean, healthy and productive marine ecosystems within all the EU Members states. The MFSD promotes an holistic, ecosystem based approach to marine conservation and monitoring (Art. 13) Monitoring strategies should: 1) focus on the potential of scale dependence in the observed dynamics and 2) be able to integrate the effect of mediating factors operating at different scale levels. However, present knowledge on spatial and temporal fluctuations in marine ecosystems is scarce. The boundaries of natural variation of several important marine ecosystem processes are still undefined. A major source of complexity is the fact that ecosystem processes are occurred across different spatial as well as temporal scales. The present knowledge gap results in uncertainty on the selection of measured parameters and the definition of sampling frequency and sites. Hereby, we discuss theoretical and applied issues related to definition of optimal cross-scale monitoring strategies. Literature data and existing databases were analyzed, to define the connectivity across nested scales of principal D1 (Biodiversity), D5 (Eutrophication), D6 (Seabed habitat integrity) MFSD descriptors. We conclude that present monitoring strategy does not completely fulfil the scaling issues due to lack of theoretical knowledge on cross-scale processes and poor coordination across monitoring operators. A stronger cooperation among member states and regional environmental agencies is needed to implement efficient cross-scale environmental monitoring. This research was developed by partners of the Integrated Regional monitoring Implementation Strategy in the South European Seas (IRIS-SES, http://iris-ses.eu) Project, a pilot project on new knowledge for an integrated management of human activities in the sea (PP/ENV D2/SEA 2012), funded by the European Union

    Implementation of Marine Framework Directive for descriptors D1, D5, D6: milestones to cope monitoring plans with natural variability. Spatial and temporal extent of monitoring water column and seabed habitats indicators, based on their scales of natural variation

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    A major source of complexity in marine ecosystem monitoring is represented by the fact that ecosystem processes occurring across different spatial and temporal scales. The implementation of the monitoring strategies applied in accordance to Marine Framework Strategy Directive (MFSD, 2008/56/EC) is a step-by-step process, which should be focus on the potential of scale dependence in the observed dynamics and should be able to integrate the effect of mediating factors operating at different scale levels. Nevertheless, the correct definition of monitoring efforts for each indicator needs to reach a well-defined knowledge on the actual assessment of the “object” of monitoring including ranges of natural variability in terms of spatial and temporal natural fluctuations. Unluckily natural fluctuations are not yet well defined in marine environments for all of the MSFD indicators. For these reasons the achievement of MSFD goals could be severely affected by the lack of knowledge which led to the lack of clear and rationale criteria on the basis of which to align and cope the scale of the assessment with the ecosystem natural fluctuations. Hereby we address the design of monitoring programmes concerning water column and seabed habitats integrity indicators (Descriptors D1, D5, D6) by discussing spatial and temporal extent of monitoring based on their scales of natural variation. The multiple layer approach developed on mesoscales could allow reducing mistakes due to sampling and methodological limits and could allow reducing problems ranging within the comprehension of mechanisms to the anticipation of consequences. The opportune mesoscale is dependent on the indicator considered and range within 0.5 – 100 km for the spatial scale and from 0.2 to 12 months for the temporal scale

    Existing monitoring of Mediterranean sea: a gap analysis

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    The Marine Strategy Framework Directive (2008/56/EC) of the European Parliament and of the Council (17th June 2008) establishes a framework for community action in the field of marine environmental policy. A crucial issue will be to improve the existing marine monitoring programs to cover the MSFD requirements. The comparison and identification of gaps in the existent national monitoring is a first step to include new parameters and frequencies of observation according to all relevant Directives and specially to MSFD. Our report is a first, integrated, cross-state assessment of the present state of Mediterranean monitoring networks. Data on monitoring stations have been provided from all member states of IRIS-SES + Croatia and joint in a unique georeferenced dataset. We used the cross-classification to build contingency tables of the counts at each combination of factor levels. Distances from coastline, densities of sampling stations, spatial overlap across descriptors, were also reported. As main results, we observed a large heterogeneity across MS on the parameters measured for each descriptors, on the density of sampling stations and on the frequency of sampling. Larger gaps have been identified for the descriptors Mammals, Birds, Reptiles (D1, D4, D6), Litter (D10), Energy & Noise (D11). The outputs from this work will be included into a GIS planning tool (Activity 3) including many scales and levels on which the MSFD Directive has been built on, such as the characteristics level (e.g. biological features, physicochemical features), pressure and impact, indicator/threshold, spatial (location of monitoring stations) and temporal (frequency-periodicity) across regions-subregions-countries

    Pelagic habitats under the MSFD D1: scientific advice of policy relevance

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    Pelagic habitats are a policy priority below Descriptor 1 (Biodiversity) of the Marine Strategy Framework Directive (MSFD). They are addressed under the D1C6 criterion, stating “the condition of the habitat type, including its biotic and abiotic structure and its functions…, is not adversely affected due to anthropogenic pressures”. The evaluation of pelagic habitats status is challenged by the functional and structural characteristics of pelagic habitat diversity and processes. To date, pelagic habitats assessments are lacking in common criteria and methodologies that characterize the habitat while accounting for the effects of anthropogenic pressures to achieve the Good Environmental Status (GES). It is therefore necessary to prioritise communication between scientific and policy communities and frame pelagic research to agree on common methods and approaches at regional or EU scale. This is key for achieving harmonised and comparable pelagic assessments for the MSFD. This report summarizes the outcomes on the assessment workflow of pelagic habitats of the JRC “MSFD pelagic habitats” workshop (9th and 10th March 2021), and the need for coordinated evaluations of the scientific challenges of policy relevance. Recommendations on the MSFD implementation of D1C6, that were generated from the experts during the workshop, will be communicated to the MSFD policy groups and the EU Member States competent authorities to support future harmonised assessment of pelagic habitats.Publications Office of the European Unio

    Editorial. A supplement of Scires-it on the COCONET european project

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    The Supplement to vol. 6, 2016 of SCIRES-IT contains the result of CoCoNet (Towards COast to COast NETworks of marine protected areas, coupled with sea-based wind energy potential), a project of the EU Oceans of Tomorrow programme (http://www.coconet-fp7.eu). The European Union requires Open Access to the results of the projects resulting from its support to scientific advancement. This is in full accordance with the policy of SCIRES-IT, an eco-sustainable open–access journal, which joins the main principles of the Berlin Declaration on Open Access with the aims of the International Convention on Biological Diversity. CoCoNet tackled two problems that are closely linked with each other: the protection of the marine environment and clean energy production. Hence, the Supplement is divided into two parts that, together, form a unicum
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