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Povzetek: Aurelia aurita s.l. is the most widespread scyphozoan jellyfish that recurrently appear “en mass” and forms large aggregations mainly in coastal waters, embayments and estuaries. Beside anthropogenic factors controlling jellyfish populations climate change may play an important role. The aim of this study was to assess whether climate-related factors in absence of other anthropogenically induced stressor influence medusae size. We investigated seasonal and interannual changes in the size of Aurelia in a “jelly lake” in the National Park of Mljet Island (Croatia) where minimal human impact on the environment makes the Veliko Jezero a natural mesocosm for understanding the impact of climate change on the Aurelia population. The observed changes suggest Aurelia medusa population response to changing environment, in particular to enhanced temperature, by reduced body sizes. Comparison of Aurelia population dynamics from different regions in the Mediterranean Sea revealed the unique feature of the Veliko Jezero population. Despite the similarity of the environmental windows of medusae occurrences in the Veliko Jezero and regions in the Mediterranean Sea, medusae in the Veliko Jezero are present all year round. It seems that the lake bathymetry enables medusae to vertically migrate to deeper and cooler water layer, avoiding the limiting temperatures developed in the upper layer during the summer. These conditions may prolong the Aurelia medusae life span and together with continuous strobilation support the stability of the Aurelia medusae population all year round.
Ključne besede: Mediterraneum, moon jellyfish, Adriatic Sea, South Adriatic Sea, marine lakes, Aurelia spp, climate-related factor, Mediterranean Sea, marine research, population dynamics
Objavljeno v DiRROS: 05.08.2024; Ogledov: 102; Prenosov: 57
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Povzetek: We examine the large-scale distribution patterns of the nano- and microphytoplankton collected from 145 oceanic stations, at 3 m depth, the 20% light level and the depth of the sub-surface chlorophyll maximum, during the Malaspina-2010 Expedition (December 2010-July 2011), which covered 15 biogeographical provinces across the Atlantic, Indian and Pacific oceans, between 35°N and 40°S. In general, the water column was stratified, the surface layers were nutrient-poor and the nano- and microplankton (hereafter phytoplankton, for simplicity, although it included also heterotrophic protists) community was dominated by dinoflagellates, other flagellates and coccolithophores, while the contribution of diatoms was only important in zones with shallow nutriclines such as the equatorial upwelling regions. We applied a principal component analysis to the correlation matrix among the abundances (after logarithmic transform) of the 76 most frequent taxa to synthesize the information contained in the phytoplankton data set. The main trends of variability identified consisted of: 1) A contrast between the community composition of the upper and the lower parts of the euphotic zone, expressed respectively by positive or negative scores of the first principal component, which was positively correlated with taxa such as the dinoflagellates Oxytoxum minutum and Scrippsiella spp., and the coccolithophores Discosphaera tubifera and Syracosphaera pulchra (HOL and HET), and negatively correlated with taxa like Ophia-ster hydroideus (coccolithophore) and several diatoms, 2) a general abundance gradient between phytoplankton-rich regions with high abundances of dinoflagellate, coccolitho-phore and ciliate taxa, and phytoplankton-poor regions (second principal component), 3) differences in dominant phytoplankton and ciliate taxa among the Atlantic, the Indian and the Pacific oceans (third principal component) and 4) the occurrence of a diatom-dominated assemblage (the fourth principal component assemblage), including several pennate taxa, Planktoniella sol, Hemiaulus hauckii and Pseudo-nitzschia spp., in the divergence regions.
Ključne besede: sea, phytoplankton, research programmes, ocean expeditions, Malaspina 2010, distribution, ocean sampling, Atlantic Ocean, Pacific, Indian Ocean
Objavljeno v DiRROS: 25.07.2024; Ogledov: 241; Prenosov: 191
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Povzetek: Planetary extinction of biodiversity underscores the need for taxonomy. Here, we scrutinizespider taxonomy over the last decade (2008–2018), compiling 2083 published accounts of newlydescribed species. We evaluated what type of data were used to delineate species, whether data weremade freely available, whether an explicit species hypothesis was stated, what types of media wereused, the sample sizes, and the degree to which species constructs were integrative. The findings wereport reveal that taxonomy remains largely descriptive, not integrative, and provides no explicitconceptual framework. Less than 4% of accounts explicitly stated a species concept and over one-thirdof all new species described were based on 1–2 specimens or only one sex. Only ~5% of studies madedata freely available, and only ~14% of all newly described species employed more than one line ofevidence, with molecular data used in ~6% of the studies. These same trends have been discovered inother animal groups, and therefore we find it logical that taxonomists face an uphill challenge whenjustifying the scientific rigor of their field and securing the needed resources. To move taxonomyforward, we make recommendations that, if implemented, will enhance its rigor, repeatability, andscientific standards.
Ključne besede: taxonomy, taxonomic crisis, species concepts, data management, monographic research
Objavljeno v DiRROS: 16.07.2024; Ogledov: 125; Prenosov: 61
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Povzetek: The challenges of achieving just, equitable and sustainable ocean futures require a new type of transdisciplinary and action-oriented science that integrates across disciplines and knowledge systems. Scientists and researchers in academia, industry or government, who contribute to knowledge creation, innovation, and policy development for the ocean, must be empowered with a fresh set of competences. This paper maps the knowledge, skills, and attitudes required to enable such a shift. The proposed skillset serves as a foundation for the design and operationalisation of modern training for ocean sustainability and is envisaged to be used by researchers both individually and in teams. It also highlights the potential for career diversification beyond the traditional ’blue jobs’ legitimated by existing sectors. To ensure the short-term practical implementation of the competence framework, self-awareness and self-reflection are encouraged among learners and teachers, along with pragmatic actions to overcome barriers to transdisciplinarity. For long-term impact, system interventions will be necessary to improve organisations’ readiness to absorb and valorise researchers trained in this new framework. This will require re-training the current pedagogical workforce as well as reframing existing knowledge systems and incentives.
Ključne besede: sustainable blue economy, sustainability science, marine sciences, transformative research, interdisciplinary sciences
Objavljeno v DiRROS: 07.05.2024; Ogledov: 261; Prenosov: 370
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Ključne besede: sports, kinesiology, children, teenagers, research, conferences, reports
Objavljeno v DiRROS: 17.04.2024; Ogledov: 331; Prenosov: 202
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