Microzooplankton composition in the winter sea ice of the Weddell Sea

Sympagic microzooplankton were studied during late winter in the northern Weddell Sea for diversity, abundance and carbon biomass. Ice cores were collected on an ice floe along three dive transects and seawater was taken from under the ice through the central dive hole from which all transects were connected. The areal and vertical microzooplankton distributions in the ice and water were compared. Abundance (max. 1300 ind. l-1) and biomass (max. 28.2 μg C l-1) were high in the ice cores and low in the water below the sea ice (max. 19 ind. l-1, 0.15 μg C l-1, respectively). The highest abundances were observed in the bottom 10 cm of the ice cores. The microzooplankton community within the sea ice comprised mainly aloricate ciliates, foraminifers and micrometazoans. In winter, microzooplankton represent an important fraction of the sympagic community in the Antarctic sea ice. They can potentially control microalgal production and contribute to particulate organic carbon concentrations when released into the water column during the ice melt in spring. Continued reduction of the sea ice may undermine the roles of microzooplankton, leading to a reduction or complete loss of diversity, abundance and biomass of these sympagic protists

Working Group “Blue”. Promotion of Low-INput Danube Agriculture in the Mura River Basin (LINDA)

Agriculture is one of the major sources of pollution of the surface water and groundwater of the Danube River Basin. Lying at the intersection of three countries – Hungary, Slovenia and Croatia, together with its transboundary groundwater body, the Mura River Basin represents a challenging pilot area with extensive agriculture. This project aims to reduce agricultural water pollution in the Mura River Basin by introducing low-input sustainable agriculture. The project will: (a) consolidate expert knowledge on low-input sustainable agricultural practices suitable for the Mura River Basin; (b) develop guidelines on the promotion of low-input agricultural practices and (c) promote their adoption by the legislatures of the three participating countries

Towards a Muon Collider

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work.Comment: 118 pages, 103 figure

Towards a muon collider

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work

Erratum: Towards a muon collider

The original online version of this article was revised: The additional reference [139] has been added. Tao Han’s ORICD ID has been incorrectly assigned to Chengcheng Han and Chengcheng Han’s ORCID ID to Tao Han. Yang Ma’s ORCID ID has been incorrectly assigned to Lianliang Ma, and Lianliang Ma’s ORCID ID to Yang Ma. The original article has been corrected

Towards a muon collider

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work

Long-term changes in abundance and diversity of tintinnids in the Gulf of Trieste (Northern Adriatic Sea)

Abundance and composition of the planktonic tintinnid ciliates were studied in the Gulf of Trieste (Northern Adriatic Sea, NE Mediterranean Sea) from July 1998 to July 2016. Tintinnids were collected biweekly-monthly from the LTER station C1 (200 m offshore, 17.5 m depth) at four depths (surface, 5 m, 10 m and 15 m). The maximum tintinnid abundance reached 4476 ind. L-1 at surface in February 2016. The tintinnid community comprised a maximum of 35 species and was dominated by the genera Stenosemella, Tintinnopsis, Codonellopsis, Salpingella and Eutintinnus. The most abundant species were Stenosemella nivalis, Tintinnopsis nana, Codonellopsis schabi, Salpingella rotundata and Eutintinnus apertus. We found a species-specific correlation with the abiotic factors considered, i.e., temperature and salinity. Temperature was positively correlated with S. rotundata and E. apertus and negatively with S. nivalis. Salinity was negatively correlated with the majority of the detected species. Agglutinated species presented winter maxima while hyaline species showed higher abundance in summer-autumn. Some key species were present over the whole period studied. Significant differences within the water column were not seen in the species composition, but were seen in the relative abundances of the same species at different depths. Stenosemella nivalis, S. ventricosa and Tintinnopsis beroidea can be considered as keystone species in the area and their possible loss can be seen as a signal of changes in the structure of the entire planktonic system

Pluridecadal Temporal Patterns of Tintinnids (Ciliophora, Spirotrichea) in Terra Nova Bay (Ross Sea, Antarctica)

During the next century, the Ross Sea is expected to reduce summer sea ice concentrations and consolidate the presence of shallower mixed layers. Those changes may have a potentially catastrophic effect on the zooplankton community. To investigate if Ross Sea’s past physical and biological condition changes have affected the tintinnids population, and to understand future tintinnids’ role in the plankton community, seawater samples collected in the Terra Nova Bay polynya area during eleven summer expeditions from 1988 to 2017 were analyzed. During this time period, tintinnids’ abundance ranged from 0 to a maximum of 4980 indL−1. The most representative species were Cymatocylis drygalskii, Codonellopsis gaussi and Laackmanniella naviculifaera. These species can be considered keystone species and they can be used to monitor the long-term evolution of the whole microzooplankton community in Terra Nova Bay polynya. The tintinnids’ abundance presented minimum values in 2001 after which there has been a significant increase in the most recent years. The increase in tintinnids’ abundance showed a positive correlation with the temperature, while salinity did not indicate any relationship. In particular, the majority of genera detected showed a significant temperature correlation, with the only exception of Amphorides genus, recorded for the first time in the study area. Our results provide new insights into the spatial distribution and structure of the Antarctic tintinnids community

Determination of metals in species of commercial interest from marine wetlands, coastal and offshore areas influenced by Po River outflows

The impact of heavy metal pollution on estuaries and coastal environments is a matter of major concern worldwide because of their persistency and tendency to bioaccumulate in the aquatic ecosystems, in addition to their toxicity [1]. These elements can derive from natural sources, influenced by bedrock geology of the drainage catchment and by weathering. However, along the Italian Northern Adriatic coast, anthropogenic pressure, in particular agriculture, industrial and municipal discharges, significantly increased the naturally occurring amounts of metals in the aquatic environment [2]. At the same time, Po delta and neighboring areas are traditionally exploited for fishery and mollusks farming, providing many species commonly used in Italian diet. In this context, the aim of this study is to evaluate the concentration of several metals (Hg, As, Cd, V, Cr, Mn, Fe, Ni, Cu, Zn, Ba, Pb) in five marine species of commercial interest collected in different environments influenced by Po River outflow. Farmed mollusks come from both wetland (Tapes philippinarum) and coastal areas (Chamelea gallina), while native mussels (Mytilus galloprovincialis) and fish species (Solea solea and Squalus acanthias) were caught offshore. All species were sampled twice between 2018 and 2019. Furthermore, the metal content was measured also in surface sediments, to assess the environmental contamination of farming and capture areas. The analytical determination was carried out by different atomic spectroscopy techniques, which were selected based on their analytical figure of merit. In detail, graphite furnace atomic absorption, cold vapor atomic absorption spectrometry (mercury analyzer), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and mass spectrometry (ICP-MS) were employed. Certified Reference Materials (CRMs) were employed for quality control purposes. The results highlighted a correlation between the environmental state of the sites and metals content in the selected samples. The metals distribution in sediments were compared with the lithogenic composition, to attempt to discriminate between natural and anthropic input sources. In addition, the concentrations found in the selected marine species were correlated with those in surface sediments, thus confirming the tendency to bioaccumulate of heavy metals. Finally, contamination levels of hazardous metals in sediments and biota were compared with Environmental Quality Standard (EQS) and threshold levels (TL) for human health