50 research outputs found

    Nonlinear Bihari Type Integral Inequalities with Maxima

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    Some new nonlinear integral inequalities that involve the maximum of the unknown scalar function of one variable are solved. The considered inequalities are generalizations of the classical nonlinear integral inequality of Bihari. The importance of these integral inequalities is defined by their wide applications in qualitative investigations of differential equations with "maxima" and it is illustrated by some direct applications

    Uspostavljanje popisa morskih invazivnih vrsta u ESENIAS području: sadašnja situacija i buduća očekivanja

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    In this study we present a list of invasive/potential invasive alien species in the East and South European Network for Invasive Alien Species (ESENIAS) countries with marine borders. The species were classified according to the existing literature and experts’ judgment, as established, casual, invasive and expected. Finally, factsheets were compiled for ten species of high importance based on their expanding/invading character. Of the 160 species comprising the list, 149 were already present in the ESENIAS countries, while eleven were invasive species either present in the Mediterranean or in other European Seas, likely to be recorded in the ESENIAS countries. The majority of the species were of Red Sea/IndoPacific origin (97 species; 60.6%). Italy, Turkey and Greece were the countries with the highest representation of species (159, 152 and 139 species respectively), due to their extended coastline and the number of scholars working on marine invasive species. The highest number of established species was recorded in Turkey (116 species), whereas in Italy and Greece the most numerous species were the “expected” ones (85 and 48 species, respectively). The eastern Adriatic Sea countries (i.e. Albania, Croatia, Montenegro and Slovenia) had generally low numbers of species in this list, many of which are still “expected” to arrive from the neighbouring countries of Greece and Italy. Finally, the most frequently potential pathway was transfer stowaways (ship ballast water: 41 cases; ship hull fouling: 55), whereas unaided spread of Lessepsian immigrants followed (95 cases). This list is intended to serve as an early warning system that through horizon scanning process would assist ESENIAS countries to prioritise invasive alien species, their pathways and the areas of higher likelihood to appear, in order to take management measures.U ovom radu predstavljamo popis invazivnih i potencijalno invazivnih vrsta na istoku i jugu Europske mreže za invazivne vrste (ESENIAS) u zemljama s morskim granicama. Vrste su klasificirane prema postojećoj literaturi i procjeni stručnjaka, pa su tako utvrđene grupe povremenih, invazivnih i očekivanih vrsta. Podaci su dati za deset vrsta čija se važnost temelji na njihovom širenju i invazivnom karakteru. Od 160 vrsta koje sadrži popis, 148 je već bilo prisutno u ESENIAS zemljama, dok je 9 invazivnih vrsta bilo prisutno u Sredozemnom ili u drugim europskim morima, a vjerojatno je da će se zabilježiti i u zemljama udruženim u ESENIAS. Većina vrsta je bile iz Crvenog mora / indopacifičkog podrijetla (97 vrsta, 60,6%). Italija, Turska i Grčka su zemlje s najvišom zastupljenošću vrsta (159, 152 i 139), zbog njihove proširene obale i broja znanstvenika koji rade na morskim invazivnim vrstama. Najveći broj utvrđenih vrsta zabilježen je u Turskoj (116 vrsta), dok su u Italiji i Grčkoj najbrojnije vrste bile “očekivane” (85 i 48 vrsta, respektivno). Istočne zemlje Jadranskog mora (npr. Albanija, Hrvatska, Crna Gora i Slovenija) imale su općenito nizak broj vrsta na ovom popisu, od kojih mnoge još “očekujemo” da pristignu iz susjednih zemalja: Grčke i Italije. Konačno, najčešće su potencijalni putovi bili „transferni putnici“ (balastna voda broda: 41 slučaj, obraštaj brodskog trupa: 55), dok je slijedilo i širenje lesepsijskih migranata (95 slučajeva). Ovaj popis je namijenjen da služi kao sustav ranog upozorenja koji bi kroz proces skeniranja pomogao državama ESENIAS da daju prioritet invazivnim stranim vrstama, njihovim putovima i područjima veće vjerojatnosti pojavljivanja, kako bi se poduzele potrebne mjere upravljanja

    A basin-wide Black Sea Mnemiopsis leidyi database

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    A specific marine biological data management tool, the Black Sea Mnemiopsis leidyi database system was created within the European Commission 6th framework Black Sea SCENE project for the Black Sea region and is now being supported by the Permanent Secretariat of the Black Sea Commission. The core team of scientists studying M. leidyi in the Black Sea was brought together and all their available M. leidyi data and metadata were loaded into the common database. This works on the Internet and has a simple user interface. It gives Black Sea scientists the option to load all their corresponding data on the database and to use it as an effective tool to work both with M. leidyi and, in future, with other gelatinous organisms’ data, including another invasive ctenophore Beroe ovata. All loaded metadata and historical data are available to the entire scientific community. More recent data are available to the team members and with some restrictions to other scientists.JRC.H.5-Land Resources Managemen

    Marine Strategy Framework Directive - Descriptor 2, Non-Indigenous Species, Delivering solid recommendations for setting threshold values for non-indigenous species pressure on European seas

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    Marine Non-Indigenous Species (NIS) are animals and plants introduced accidently or deliberately into the European seas, originating from other seas of the globe. About 800 marine non-indigenous species (NIS) currently occur in the European Union national marine waters, several of which have negative impacts on marine ecosystem services and biodiversity. Under the Marine Strategy Framework Directive (MSFD) Descriptor 2 (D2), EU Member States (MSs) need to consider NIS in their marine management strategies. The Descriptor D2 includes one primary criterion (D2C1: new NIS introductions), and two secondary criteria (D2C2 and D2C3). The D2 implementation is characterized by a number of issues and uncertainties which can be applicable to the Descriptor level (e.g. geographical unit of assessment, assessment period, phytoplanktonic, parasitic, oligohaline NIS, etc.), to the primary criterion D2C1 level (e.g. threshold values, cryptogenic, questionable species, etc), and to the secondary criteria D2C2 and D2C3. The current report tackles these issues and provides practical recommendations aiming at a smoother and more efficient implementation of D2 and its criteria at EU level. They constitute a solid operational output which can result in more comparable D2 assessments among MSs and MSFD regions/subregions. When it comes to the policy-side, the current report calls for a number of different categories of NIS to be reported in D2 assessments, pointing the need for the species to be labelled/categorised appropriately in the MSFD reporting by the MSs. These suggestions are proposed to be communicated to the MSFD Working Group of Good Environmental Status (GES) and subsequently to the Marine Strategy Coordination Group (MSCG) of MSFD. Moreover, they can serve as an input for revising the Art. 8 Guidelines

    A MSFD complementary approach for the assessment of pressures, knowledge and data gaps in Southern European Seas : the PERSEUS experience

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    PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also independently performed. The comparison between meta-analysis results and IAs shows similarities for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification of additional research themes targeting research topics that are requested to the achievement of GES. 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license.peer-reviewe

    Ocean current connectivity propelling the secondary spread of a marine invasive comb jelly across western Eurasia

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    Publication history: Accepted - 15 February 2018; Published - 16 May 2018.Aim: Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further distribution after the initial establishment of non-native species remain largely unresolved, especially in marine systems. Ocean currents can be a major driver governing range occupancy, but this has not been accounted for in most invasion ecology studies so far. We investigate how well initial establishment areas are interconnected to later occupancy regions to test for the potential role of ocean currents driving secondary spread dynamics in order to infer invasion corridors and the source–sink dynamics of a non-native holoplanktonic biological probe species on a continental scale. Location: Western Eurasia. Time period: 1980s–2016. Major taxa studied: ‘Comb jelly’ Mnemiopsis leidyi. Methods: Based on 12,400 geo-referenced occurrence data, we reconstruct the invasion history of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the temporal and spatial spread dynamics with large-scale connectivity patterns via ocean currents. Additionally, genetic markers are used to test the predicted connectivity between subpopulations. Results: Ocean currents can explain secondary spread dynamics, matching observed range expansions and the timing of first occurrence of our holoplanktonic non-native biological probe species, leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year-round populations in highly interconnected regions can re-seed genotypes over large distances after local extinctions. Main conclusions: Although the release of ballast water from container ships may contribute to the dispersal of non-native species, our results highlight the importance of ocean currents driving secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for secondary spread dynamics on a continental scale. Invasion risk assessments should consider large-scale connectivity patterns and the potential source regions of non-native marine species.Danish Council for Independent Research; Grant/Award Number: DFF-1325-00102B; FP7 People: Marie-Curie Actions, Grant/Award Number: MOBILEX, DFF - 1325-00025; EU, BONUS, BMBF, Grant/ Award Number: 03F0682; Excellence Cluster “Future Ocean”, Grant/Award Number: CP153

    Non-indigenous species refined national baseline inventories: A synthesis in the context of the European Union's Marine Strategy Framework Directive

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    Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions.Henn Ojaveer and Maiju Lehtiniemi wish to acknowledge the project COMPLETE (Completing management options in the Baltic Sea region to reduce risk of invasive species introduction by shipping), co-financed by the European Union's funding Programme Interreg Baltic Sea Region (European Regional Development Fund). João Canning-Clode was supported by a starting grant in the framework of the 2014 FCT Investigator Programme (IF/01606/2014/CP1230/CT0001) and wish to acknowledge the support of Fundação para a Ciência e Tecnologia (FCT), through the strategic project UID/MAR/04292/2019 granted to MARE

    Non-indigenous species refined national baseline inventories : A synthesis in the context of the European Union's Marine Strategy Framework Directive

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    Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions. Highlights • Refined MSFD baseline inventories of non-indigenous species (NIS) are set in EU. • The inventories are given per EU Member State (MS) and MSFD subregion up to 2012. • The NIS lists provide a basis for reporting new NIS introductions in EU after 2012. • Our work constitutes a milestone for the MSFD Descriptor 2 implementation

    Marine biodiversity and ecosystem function relationships: The potential for practical monitoring applications

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    Abundance of mesozooplankton in the western part of the Black Sea during the 2001 National Monitoring Programme of the Bulgarian Institute of Oceanography

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    The dataset is based on samples collected in the autumn of 2001 in the Western Black Sea in front of Bulgaria coast. The whole dataset is composed of 42 samples (from 19 stations of National Monitoring Grid) with data of mesozooplankton species composition abundance and biomass. Samples were collected in the layers 0-10, 0-20, 0-50, 10-25, 25-50, 50-100 and from bottom up to the surface at depths depending on water column stratification and the thermocline depth. Zooplankton samples were collected with vertical closing Juday net,diameter - 36cm, mesh size 150 µm. Tows were performed from surface down to bottom meters depths in discrete layers. Samples were preserved by a 4% formaldehyde sea water buffered solution. Sampling volume was estimated by multiplying the mouth area with the wire length. Mesozooplankton abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Kremena Stefanova using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972). Taxon-specific abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Copepods and Cladoceras were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Kremena Stefanova using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972)
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