Grandidierella japonica (Amphipoda: Aoridae): a non-indigenous species in a Po delta lagoon of the northern Adriatic (Mediterranean Sea)

The introduction and spread of non-indigenous species is one of the main threats to biodiversity of aquatic ecosystems and it is becoming an increasing problem for the international scientific community. Aquaculture and related activities are recognized as one of the most important drivers of non-indigenous species in the Mediterranean. Grandidierella japonica Stephensen, 1938 is an aorid amphipod species native of Japan. This species had previously only been reported a few times outside the Pacific region, in particular from coastal waters of England and French Atlantic coasts. A population of the non-indigenous amphipod G. japonica, has been detected in the Sacca di Goro, a Po delta lagoon of the northern Adriatic Sea (Italy), representing the first record of this species in the Mediterranean Sea. Adults of both sexes and juveniles were collected in muddy sediments reaching high densities. We examined 24 specimens: 8 adult males, 12 females, and 4 undifferentiated juveniles. Our specimens displayed a variability in the position of teeth of male gnathopod 1. Likely vectors for this introduction are the commercial shellfish transplants, mainly oyster farming. The finding of a reproducing population of G. japonica suggests that the species has become well established in the Sacca di Goro. This finding also seems to be particularly relevant for the improvement on the knowledge of Mediterranean biodiversity and threats

Management and Exploitation of Macroalgal Biomass as a Tool for the Recovery of Transitional Water Systems

Aquatic angiosperms favor the development of ecosystems services, the welfare of marine organisms and people. Generally, the presence of angiosperms in transitional water systems (TWS) are indicators of good ecosystem status. Presently, these environments are densely populated and often are so highly degraded that angiosperms have almost disappeared, replaced by tionitrophilic macroalgae responsible of anoxic events that deteriorate the environment furtherly. Although this trend is hardly reversible because the anthropogenic impact is increasing and the restoring of damaged environments within a reasonable time is difficult, recent studies have shown that by managing the harvesting of the natural algal species of commercial interest a progressive environmental recovery is achievable. Biomass-harvesting can contribute both to the removal of high amounts of nutrients and the generation of economic revenues for a sustainable, self-financed environmental restoration. In fact, unlike clam-farming which destroys the seabed and re-suspends large amounts of sediments, the proper management of the macroalgal biomass, can favor the nutrient abatement and the recolonization of aquatic angiosperms which help restore the conditions necessary for the conservation of the benthic and fish fauna and birds, and produce valuable economic resources

Benthic studies in LTER sites: the use of taxonomy surrogates in the detection of long-term changes in lagoonal benthic assemblages

In benthic studies, the identification of organisms at the species level is known to be the best source for ecological and biological information even if time-consuming and expensive. However, taxonomic sufficiency (TS) has been proposed as a short-cut method for quantifying changes in biological assemblages in environmental monitoring. In this paper, we set out to determine whether and how the taxonomic complexity of a benthic assemblage influences the results of TS at two different long-term ecological research (LTER) sites in the Po delta region (north-eastern Italy). Specifically, we investigated whether TS can be used to detect natural and human-driven patterns of variation in benthic assemblages from lagoonal soft bottoms. The first benthic dataset was collected from 1996 to 2015 in a “choked” lagoon, the Valli di Comacchio, a lagoon characterised by long water residence times and heavy eutrophication, while the second was collected from 2004 to 2010 in a “leaky” lagoon, the Sacca di Goro, a coastal area with human pressure limited to aquaculture. Univariate and multivariate statistical analyses were used to assess differences in the taxonomic structure of benthic assemblages and to test TS on the two different datasets. TS seemed to work from species to family level at both sites, despite a higher natural variability of environmental conditions combined with multiple anthropogenic stressors. Therefore, TS at the family level may represent effective taxonomic surrogates across a range of environmental contexts in lagoon environments. Since the structure of the community and the magnitude of changes could influence the efficiency of taxonomic surrogates and data transformations in long-term monitoring, we also suggest periodic analyses at finer taxonomic levels in order to check the efficiency of the application of taxonomic substitutes in routine monitoring programmes in lagoon systems

Long-term changes of the trophic status in transitional ecosystems of the northern Adriatic Sea, key parameters and future expectations: The lagoon of Venice as a study case.

The determination of the trophic status of transitional ecosystems from the physico-chemical and biological point of view is one of the requirements of the European Water Framework Directive (WFD 2000/60/EC). In Italy, its determination is implemented by the Regional Agencies for Environmental Protection (ARPAs) that have activated multi-annual monitoring programs. However, as the availability of funds is increasingly scarce, the number of environmental parameters to detect environmental changes should be conveniently managed. The high number of environmental parameters, nutrient and macrophyte datasets available for the LTER-Italia site “Venice lagoon” can be an useful tool to analyze the trophic changes over recent years and to foresee environmental evolutions. Nutrient data on a spatial basis have been available since 1948, whereas macroalgal maps date back to 1980. The aim of this paper is to highlight the changes of the trophic status of the lagoon since the middle of the 20th century by considering the concentrations of nutrients in the surface sediments and in the water column, the variation of some physico-chemical parameters and the biomass of macroalgae and also to foresee the way it will possibly evolve. In fact, after many anthropogenic impacts that in the second half of the 20th century affected the lagoon, starting fromthe year 2010, the ecological status is progressively improving. Nutrients show a significant reduction both in the water column and in surface sediments, and the macrophytes are represented by species of higher ecological value while the opportunistic species such as the Ulvaceae are in strong regression

Trends of Nitrogen and Phosphorus in Surface Sediments of the Lagoons of the Northern Adriatic Sea

The analysis of nutrient concentrations in surface sediments is a reliable tool for assessing the trophic status of a water body. Nitrogen and phosphorus concentrations are strongly related to the sediment characteristics but are mainly driven by anthropogenic impacts. The results of the determination of total nitrogen and total inorganic and organic phosphorus in surface sediments of the lagoons and ponds of the northwestern Adriatic Sea (Marano-Grado, Venice, Po Delta, Comacchio Valleys, Pialassa della Baiona) show the merit of this approach. Indeed, when previous data are available, the ratio between the actual and background values can provide useful information on the trophic changes that have occurred in the most recent times, and the results can also explain the conditions present in less studied environments. In this context, numerous studies performed in the Venice lagoon since the second half of the 20th century during different environmental scenarios provide mean concentration ranges and propose the main causes of changes. The results of single datasets available for the other lagoons fall into scenarios that occurred in the Venice lagoon. At present, the most eutrophic basins are Pialassa della Baiona, the Po Delta lagoons and ponds and the Comacchio valleys due to industrial effluents, fish farming and clam harvesting, respectively, whereas the Venice lagoon is now experiencing environmental recovery

Hazardous effects of silver nanoparticles for primary producers in transitional water systems: The case of the seaweed Ulva rigida C. Agardh

Abstract The acute toxicity of citrate capped silver nanoparticles (AgNP) and silver nitrate was evaluated on the marine macroalga Ulva rigida C. Agardh (1823). Silver bioaccumulation, ultrastructural chloroplast damages verified by TEM microscopy, inhibition of primary production, neutral lipid production and oxidative stress were observed after 24 h of exposure to AgNP. The toxic effects of silver nitrate in artificial seawater started from a concentration of 0.05 ppm and was more toxic than AgNP that produced effects from a concentration of 0.1 ppm. However only AgNP induced lipid peroxidation in U. rigida. The addition of natural organic and inorganic ligands, represented by transparent exopolymer particles (TEP) and clay, drastically reduced AgNP acute toxicity in a ratio AgNP:ligand of 1:100 and 1:200, respectively. The findings suggest a marked toxicity of Ag on marine macroalgae which however should be mitigated by the high natural ligand concentrations of the transitional environments

Microplastic accumulation in benthic invertebrates in Terra Nova Bay (Ross Sea, Antarctica)

Microplastic contamination of the benthic invertebrate fauna in Terra Nova Bay (Ross Sea, Antarctica) was determined. Twelve macrobenthic species, characterized by different feeding strategies, were selected at 3 sampling sites at increasing distance from the Italian Scientific Base (Mario Zucchelli, Camp Icarus, Adelie Cove). The 83% of the analyzed macrobenthic species contained microplastics (0.01–3.29 items mg−1). The size of the particles, measured by Feret diameter, ranged from 33 to 1000 µm with the highest relative abundance between 50 and 100 µm. Filter-feeders and grazers displayed values of microplastic contamination from 3 to 5 times higher than omnivores and predators, leading to the hypothesis that there is no evident bioaccumulation through the food web. The prevalent polymers identified by micro-FTIR were nylon (86%) and polyethylene (5%); other polymers identified in Antarctic benthos were polytetrafluoroethylene, polyoxymethylene, phenolic resin, polypropylene, polystyrene resin and XT polymer. Keywords: Antarctica, Benthos, Microplastics, Food web, FTIR, Nile re

Morphological characterization of the antenna of Torymus sinensis (Hymenoptera: Torymidae) and a comparison within the superfamily Chalcidoidea

The parasitoid Torymus sinensis (Hymenoptera: Torymidae) has been successfully used in Italy since 2005 for biological control of the invasive cynipid Dryocosmus kuriphilus (Hymenoptera: Cynipidae), highly destructive for the economically relevant Castanea sativa (Fagales: Fagaceae). In order to investigate the morphological aspects related to sensorial behavior, a fine morphology study of the antennae and their sensilla was conducted by scanning electron microscopy on both sexes of T. sinensis. The antennae, composed of a scape, a pedicel and a flagellum with ten flagellomeres, had chaetic sensilla of six sub types, placoid sensilla of three subtypes, trichoid sensilla, sensilla with a roundish grooved tip, and coeloconic sensilla. The chaetic sensilla of the first three subtypes were found in the scape and in the pedicel, and those of the last three subtypes, together with trichoid, roundish grooved tip and coeloconic sensilla, were found only on flagellomeres. Sexual dimorphism was detected in the morphology of the proper pedicel and the flagellum, and in the presence and distribution of the sensilla and their subtypes. The morphological aspects of the antenna of T. sinensis and of its sensilla were compared with those found in the family Torymidae and in other families of the extremely diverse superfamily Chalcidoide

The Italian long-term ecosystem research (LTER-Italy) network: results, opportunities, and challenges for coastal transitional ecosystems

1 - The Long-Term Ecosystem Research (LTER) network, now a global reality, was founded on a combination of long-term ecological studies, short-term experiments, and comparisons among sites and eco-domains. 2 - The LTER-Italy network was officially established as a formal member of the LTER international network in 2006, following a wider on-going process in Europe; it currently consists of 22 sites representing the main ecosystem typologies of Italy. Four coastal transitional ecosystem sites are included in the LTER-Italy network: on the northern Peninsula, these include the Venice Lagoon and the lagoons of the Po River Delta, which are characterized by a temperate climate and the influence of tides; and in the southern sector, these include the coastal ecosystems of Sardinia and the Mar Piccolo of Taranto, which are characterized by a Mediterranean climate and the absence of sensible tides. 3 - In this paper, we present and discuss three main issues: the LTER-International and LTER-Europe context, emphasising the most practical issues and activities that must be addressed for the effective organization and maintenance of LTER networks; the history, structure, and perspectives of the national LTER-Italy network; and the opportunities, strengths, and weaknesses related to participation of the LTER-Italy network in the study of coastal transitional ecosystems

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy