A case study of sewage discharge in the shallow coastal area of the Northern Adriatic Sea (Gulf of Trieste)

A case study was carried out in 2000 in the shallow coastal area of the Northern Adriatic Sea (Gulf of Trieste) where untreated domestic sewage and industrial wastes are discharged at rate of 5500 m³·day^?1. The sewage plume above the outfall was followed using faecal coliforms (FC) and overturning length scale (l_T). The latter was rejected as a marker as the discharge conditions prohibit following the turbulence of sewage water. Intermittent sewage discharge is reflected in the minimal effect of eutrophication. Increase of phytoplankton biomass is thus only minor compared with the unpolluted area regardless of elevated concentrations of sewage‐derived nutrients (confirmed by correlation coefficients between FC and NH₄⁺, TP, PO₄^3?: 0.78, 0.71 and 0.67, respectively). Deteriorated trophic status, determined by the TRIX index, was observed only in the surface layer (average TRIX: 5.67). High FC content well above the regulation limit (up to 2.6 × 10⁵ FC·100 ml^?1) represents, therefore, the major negative impact of the improperly treated waste for the risk to human health.     

Visibility of Prominences Using the He <Emphasis Type="SmallCaps">i</Emphasis> D<Subscript>3</Subscript> Line Filter on the PROBA-3/ASPIICS Coronagraph

We determine the optimal width and shape of the narrow-band filter centered on the He?i D₃ line for prominence and coronal mass ejection (CME) observations with the ASPIICS (Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun) coronagraph onboard the PROBA-3 (Project for On-board Autonomy) satellite, to be launched in 2020. We analyze He?i D₃ line intensities for three representative non-local thermal equilibrium prominence models at temperatures 8, 30, and 100 kK computed with a radiative transfer code and the prominence visible-light (VL) emission due to Thomson scattering on the prominence electrons. We compute various useful relations at prominence line-of-sight velocities of 0, 100, and 300 km?s^?1 for 20 Å wide flat filter and three Gaussian filters with a full-width at half-maximum (FWHM) equal to 5, 10, and 20 Å to show the relative brightness contribution of the He?i D₃ line and the prominence VL to the visibility in a given narrow-band filter. We also discuss possible signal contamination by Na?i D₁ and D₂ lines, which otherwise may be useful to detect comets. Our results mainly show that i) an optimal narrow-band filter should be flat or somewhere between flat and Gaussian with an FWHM of 20 Å in order to detect fast-moving prominence structures, ii) the maximum emission in the He?i D₃ line is at 30 kK and the minimal at 100 kK, and iii) the ratio of emission in the He?i D₃ line to the VL emission can provide a useful diagnostic for the temperature of prominence structures. This ratio is up to 10 for hot prominence structures, up to 100 for cool structures, and up to 1000 for warm structures.     

Mesozooplankton spatial distribution and community structure in the South Adriatic Sea during two winters (2015, 2016)

Whereas the data on mesozooplankton in the epipelagic offshore Mediterranean Sea are extensive, less information is available about plankton in the deeper layers. The present study aims to describe the vertical and horizontal structure and distribution of mesozooplankton species and their associations down to 1,200 m in the water of the Southern Adriatic Sea. Zooplankton were sampled using a Nansen net of 200‐μm mesh size during two cruises in the winters of 2015 and 2016, extending from the coast to the open sea. In total, 203 zooplankton taxa were identified. The community was dominated by copepods, representing between 67% and 91% of the total abundance. The highest total densities were recorded in the upper layers where a high proportion (up to 36%) of appendicularians was also observed in the first sampled year. Five groups of samples were determined based on their community structure. In 2015 communities were distinct between the 0 and 50 m layer and the underlying one (50–100 m), whereas in 2016 epipelagic waters were inhabited by a more uniform mesozooplankton community. The mesopelagic and deep‐water fauna, especially copepods, showed a relatively stable composition in both sampling years Overall, our study confirms the oligotrophic character of the Southern Adriatic, with occasional density outbreaks of appendicularians under favourable conditions.     

Quantitative morphometric analysis of the Jama River profile in a tectonically active margin (Northwestern Ecuador)

The longitudinal profile of a river channel can be described in function of mathematical expressions. The logarithmic fit is the most used method to describe the relative equilibrium of a channel elevation profile. Rivers showing zones of high channel gradient and convex-upward profiles can be evaluated in function of the offset distance with respect to the logarithmic curve. The Jama River profile has been constructed using differential GPS data for the downstream reach and 4-m-grid DEM data base for the remaining headward profile. The resulting longitudinal profile shows a prominent knickpoint of about 80 m in elevation characterized by sharp local convexity. The offset distance in vertical direction from the logarithmic plot is interpreted as the successive accumulation of multiple uplift episodes associated with the Jama Fault System activity. The horizontal offset is suggested to represent the remaining retreated distance for the upstream propagation of the Jama knickpoint. The highly resistant Cretaceous rocks outcropping along the Jama knickpoint reach acts as an inflection point between two subprofiles that show well-fitted logarithmic curves, thereby representing a temporary partitioned equilibrium along the Jama River profile.     

IGR J17445-2747—Yet another X-ray burster in the galactic bulge

The discovery of a type I X-ray burst from the faint unidentified transient source IGR J17445-2747 in the Galactic bulge by the JEM-X telescope onboard the INTEGRAL observatory is reported. Type I bursts are believed to be associated with thermonuclear explosions of accreted matter on the surface of a neutron star with a weak magnetic field in a low-mass X-ray binary. Thus, this observation allows the nature of this source to be established.     

Meridional Motion and Reynolds Stress from Debrecen Photoheliographic Data

The Debrecen Photoheliographic Data catalogue is a continuation of the Greenwich Photoheliographic Results providing daily positions of sunspots and sunspot groups. We analyse the data for sunspot groups focussing on meridional motions and transfer of angular momentum towards the solar equator. Velocities are calculated with a daily shift method including an automatic iterative process of removing the outliers. Apart from the standard differential rotation profile, we find meridional motion directed towards the zone of solar activity. The difference in measured meridional flow in comparison to Doppler measurements and some other tracer measurements is interpreted as a consequence of different flow patterns inside and outside of active regions. We also find a statistically significant dependence of meridional motion on rotation velocity residuals confirming the transfer of angular momentum towards the equator. Analysis of horizontal Reynolds stress reveals that the transfer of angular momentum is stronger with increasing latitude up to about \(40^{\circ}\), where there is a possible maximum in absolute value.     

Chemical signature of intermediate water masses along western Portuguese margin

Although the circulation of intermediate water masses in the eastern North Atlantic remains poorly defined, the presence of fresher intermediate waters, the Sub-Artic (SAIW) and the Antarctic Intermediate Water (AAIW), as well the saline intermediate Mediterranean Water (MW), has been tracked using biogeochemical properties. Here we assess the hydrographic and chemical structures of intermediate waters along the western Portuguese margin by examining the vertical distributions and property-property plots of chemical tracers (oxygen and nutrients). AAIW was traced by low oxygen and high nutrients, while SAIW was recognized by low nutrients. The Mediterranean Water (MW) undercurrent is shown to spread towards the eastern flank of Gorringe bank. Concurrently, the fresher waters gained salt by direct incorporation of MW, while this water was enriched in nutrients on its way northward and westward owing, to a great extent, to the entrainment of an AAIW branch. The distributions of nutrients and apparent oxygen utilization are discussed in terms of regional ocean circulation. Our analysis suggests a circulation pattern of the various intermediate waters along the western Portuguese margin: MW extends all over the area, but its presence is more pronounced around cape St. Vincent; SAIW apparently moves southward, reaching the Gorringe bank region, and AAIW flows northward along the coast and around the bank.     

Evaluation of site conditions for the Ankara Basin of Turkey based on seismic site characterization of near-surface geologic materials

Regional site conditions relevant for seismic hazard studies can be derived from various geologic, seismologic, and geotechnical sources. In this study, site conditions are derived for the Ankara Basin in Turkey by merging in-situ seismic measurements of dynamic properties, geologic information, and some geotechnical boring information. Field seismic refraction surveys were performed at 259 sites in the project area to classify and characterize Plio–Pleistocene fluvial deposits and Quaternary alluvial and terrace deposits. The shear-wave velocity profiles of the near-surface geologic units are used to characterize site classes according to the International Building Code [International Code Council, ICC. International Building Code. Structural and fire- and life-safety provisions (seismic, wind, accessibility, egress, occupancy and roof codes), 2006. Whittier, CA.] and the Turkish Seismic Code [Ministry of Public Works and Settlement, 1998. Turkish Seismic Code, Specification for Structures to be Built in Disaster Areas, Ankara, Turkey], and to develop a regional model for the average shear-wave velocity in the top 30 m. The resulting maps of site class indicate that the classification system for the Turkish Seismic Code results in a significant portion of the Ankara Basin being classified as Z4, the softest site class. The International Building Code site classification system results in most of the Ankara Basin being classified as D, stiff soil. These differences are caused by the Turkish Seismic Code incorporating information from only the surface layer, while the International Building Code incorporates information from the top 30 m.     

Impoverishment of recent floodplain forest mollusc fauna in the lower Ohře River (Czech Republic) as a result of prehistoric human impact

Analyses of fossil mollusc successions have rarely been used to study the development of floodplain forests during the Holocene. The Oh?e River, located in a prehistorically settled chernozem area in the Czech Republic, is partly situated in Cretaceous marlstones, yielding sediments suitable for fossilization directly in floodplain deposits. We analysed five fossil mollusc successions situated in the lower stretch of the Oh?e River and compared the results with recent mollusc assemblages studied along the entire 256 km of the river. Fossil samples were composed mostly of open‐country species throughout the Holocene or the whole preserved succession. Only some samples also contained woodland assemblages, but these were always greatly impoverished, with a very low frequency of strictly woodland species. Although the natural‐looking appearance of the present‐day floodplain forests of the lower river stretch has resulted in its being declared a nature reserve, modern floodplain forest mollusc assemblages there are also impoverished. This reduction in the distribution of strictly woodland species compared with modern assemblages in the upper stretch of the river seems to be the result of an ancient human settlement and continuous disturbances of the floodplain forest development since the Neolithic. Thus, fully developed floodplain forest assemblages occur recently only in the upper non‐impacted stretch of the river. Based on the studied fossil successions we can conclude that the lower Oh?e River floodplain was probably a mosaic of open and disturbed forest habitats throughout the Holocene. This area is part of a central European landscape island, where forests probably never fully developed and open patches from the early Holocene continually developed into an agricultural landscape.