Ponto-Caspian Species Hypania invalida (Grube, 1860) (Polychaeta, Ampharetidae) in the Inland Waters of Europe: Modern Distribution and the Paleorefugium Hypothesis

The Cebala Borj-Touil irrigation perimeter in the low valley of the Medjerda River is marked by a shallow saline groundwater rise. The seasonal water salinity shows a high spatial and temporal variation. This study introduces a novel methodological approach dealing with the data scarcity problem in a complex deltaic area, using only available data and numerical models. The numerical model FEFLOW was used to simulate the shallow groundwater flow and salt transfer. Several simulations were run to explore future trends of groundwater salinity under different climate change (CC) conditions. The results show a significant increase in water salinity under all the climatic scenarios. A 15% decrease in precipitation leads to an average increase in salinity of 10–15 g/l. The significant rise in sea level also affects the salinization process. The intrusion of seawater results in concentrations of salinity between 16 and 20 g/l. In addition, the quality of irrigation water has a marked impact, contributing to a significant increase in salinity, reaching a maximum of 15 g/l. These concerning results are to be expected, as the coastal study area is characterized by a semi-arid climate and is increasingly influenced by anthropogenic factors, including irrigation practices and drainage deficiency.

Aim Hidden diversity within an invasive ‘species’ can mask both invasion pathways and confound management goals. We assessed taxonomic status and population structure of the monkey goby Neogobius fluviatilis across Eurasia, comparing genetic variation across its native and invasive ranges.Location Native populations were analysed within the Black and Caspian Sea basins, including major river drainages (Dnieper, Dniester, Danube, Don and Volga rivers), along with introduced locations within the upper Danube and Vistula river systems.Methods DNA sequences and 10 nuclear microsatellite loci were analysed to test genetic diversity and divergence patterns of native and introduced populations; phylogenetic analysis of mtDNA cytochrome b and nuclear RAG‐1 sequences assessed taxonomic status of Black and Caspian Sea lineages. Multivariate analysis of morphology was used to corroborate phylogenetic patterns. Population genetic structure within each basin was evaluated with mtDNA and microsatellite data using FST analogues and Bayesian assignment tests.Results Phylogenetic analysis of mitochondrial and nuclear sequences discerned a pronounced genetic break between monkey gobies in the Black and Caspian Seas, indicating a long‐term species‐level separation dating to c. 3 million years. This pronounced separation further was confirmed from morphological and population genetic divergence. Bayesian inference showed congruent patterns of population structure within the Black Sea basin. Introduced populations in the Danube and Vistula River basins traced to north‐west Black Sea origins, a genetic expansion pattern matching that of other introduced Ponto‐Caspian gobiids.Main conclusions Both genetic and morphological data strongly supported two species of monkey gobies that were formerly identified as subspecies: N. fluviatilis in the Black Sea basin, Don and Volga Rivers, and the Kumo‐Manych Depression, and Neogobius pallasi in the Caspian Sea and Volga River delta. Genetic origins of introduced N. fluviatilis populations indicated a common invasion pathway shared with other introduced Ponto‐Caspian fishes and invertebrates.

Freshwater from rivers influences Indian summer monsoon rainfall and tropical cyclones by stratifying the upper layer and warming the subsurface ocean in the Bay of Bengal (BoB). Here, we use in situ and satellite data with reanalysis to showcase how river water experiences a significant increase in salinity on sub‐seasonal timescales. This involves the trapping and homogenization of freshwater by a cyclonic eddy in the Bay. Using a specific example from 2015, river water is shown to enter an eddy along its attracting manifolds within a period of 2 weeks. This leads to the formation of a highly stratified subsurface layer within the eddy. When freshest, the eddy has the largest sea‐level anomaly, spins fastest, and supports strong lateral gradients in salinity. Subsequently, observations reveal a progressive increase in salinity inside the eddy within a month. In particular, salty water spirals in, and freshwater is pulled out across the eddy boundary. Lagrangian experiments elucidate this process, whereby horizontal chaotic mixing provides a mechanism for the rapid increase in surface salinity. A salinity budget also suggests that horizontal advection explains much of the change in mixed layer salinity. Further, the adjustment of this freshwater eddy triggers submesoscale dynamics which appear to be an integral part of the process of salinity homogenization. This pathway is distinct from vertical diffusive mixing and is likely to be important for the evolution of salinity in the BoB.

Freshwater from rivers influences Indian summer monsoon rainfall and tropical cyclones by stratifying the upper layer and warming the subsurface ocean in the Bay of Bengal. Here, we use {\it in situ} and satellite data with reanalysis to showcase how river water experiences a significant increase in salinity on sub-seasonal timescales. This involves the trapping and homogenization of freshwater by a cyclonic eddy in the Bay. Using a specific example from 2015, river water is shown to enter an eddy along its attracting manifolds within a period of two weeks. This leads to the formation of a highly stratified subsurface layer within the eddy. When freshest, the eddy has the largest sea-level anomaly, spins fastest, and supports strong lateral gradients in salinity. Subsequently, observations reveal a progressive increase in salinity inside the eddy within a month. In particular, salty water spirals in, and freshwater is pulled out across the eddy boundary. Lagrangian experiments elucidate this process, whereby horizontal chaotic mixing provides a mechanism for the rapid increase in surface salinity. A salinity budget also suggests that horizontal advection explains much of the change in mixed layer salinity. Further, the adjustment of this freshwater eddy triggers submesoscale dynamics which appear to be an integral part of the process of salinity homogenization. This pathway is distinct from vertical diffusive mixing and is likely to be important for the evolution of salinity in the Bay of Bengal.

The political downfall of the Western Roman empire in 467 at first did not bring about many changes in the economic life of Western and Southern Europe. This changed when in the seventh century the advancing Arabs had occupied the eastern, southern and western shores of the Mediterranean. Their advance brought to a virtual halt the old trade relations between Western Europe and the Near East. The little trade that remained in Western Europe was terminated not much later by the predatory raids of the Vikings and by the invasions of the Huns and the Hungarians which cut off the old trade routes between the Baltic Sea and the Black Sea and those in the Danube valley. Northwestern and Central Europe were consequently more or less cordoned off and trade came almost entirely to a standstill: only via Italy, which had remained a part of the still extant Eastern Roman empire, were commercial relations with the East maintained. From the eighth century onward agriculture occupied the most important place in economic life. The significance of the countryside increased while the cities fell into decline. It is understandable that this more or less isolated society, which relied so heavily on agriculture and which was almost continuously in a state of war, showed little concern for science. Only the Church and the royal Chancelleries could provide people who were able to read and write, and consequently it was mainly servants of the Church who had access to the written legacy of previous centuries.

Temperate grasslands belong to the most diverse plant communities of Central Europe. However, there is still a lack of information about glacial refugia and migration processes of herbaceous grassland and especially steppe species in Central Europe. Therefore, we analyzed the survival and postglacial immigration of Scorzonera purpurea to Central Europe. We investigated 348 individuals from 37 populations in Europe using amplified fragment length polymorphisms and chloroplast microsatellite analyses. Our study revealed two major genetic groups along the European distribution range consisting of western populations on the one hand and closely related central and (south)eastern populations on the other hand. Genetic variation was highest within populations from the Pannonian basin and decreased toward Western and Central Europe. Our study gives evidence for the long-term survival of S. purpurea in Western Europe and the postglacial immigration from the southeastern parts of Europe, maybe by domestic livestock of migrating farmers during the Neolithic age to Central Europe. Immigration presumably followed two routes from Pannonia along the river Danube into Southern Germany and from Pannonia along the northern border of the Carpathians to Northern Germany. In Central Germany, the different genetic lineages may have met and formed contact zones. Our data show that steppe species may both have survived in and immigrated to Western and Central Europe. Further and more detailed studies on other steppe species are, therefore, needed to investigate the origin of these rare and often endangered species more generally.

Leg 10 interstitial water analyses provide new indications of the distribution of rock salt beneath the floor of the Gulf of Mexico, both confirming areas previously indicated to be underlain by salt bodies and extending evidence of salt distribution to seismically featureless areas in the Sigsbee Knolls trend and Isthmian Embayment. The criterion for presence of salt at depth is a consistent increase in interstitial salinity and chlorinity with depth. Site 86, on the northern margin of the Yucatan Platform, provided no evidence of salt at depth. Thus, our data tend to rule out the suggestion of Antoine and Bryant (1969) that the Sigsbee Knolls salt was squeezed out from beneath the Yucatan Scarp. Cores from Sites 90 and 91, in the central Sigsbee Deep, were not obtained from a great enough depth to yield definite evidence for the presence of buried salt. INTRODUCTION Materials cored at Leg 10 sites consist largely of rapidly deposited Tertiary marly sediments. One of the chief areas of interest in the Gulf of Mexico is the documented presence of salt at depth, both under the northern margin of the gulf (Uchupi and Emery, 1968; Murray, 1966; Paine and Meyerhoff, 1970; Lehner, 1969) and in the Sigsbee Knolls area (Burk et al., 1969, and references cited therein). Study of pore fluids in DSDP Leg 1 cores (Manheim and Sayles, 1970, and references cited therein) extended the previous study of pore fluids from the northern margin of the gulf (Manheim and BischofF, 1969) and demonstrated that diffusion of salt establishes a characteristic salinity and chlorinity gradient in sediments that lie above rock salt. Where enough geologic time has elapsed, the presence of salt more than 3 km below the lowest penetrated horizon can be established by pore fluid studies. This happened in the case of Site 3, where the hole bottomed at 620 meters, while seismic basement was estimated to be 4000 meters below the sea floor (J.L. Worzel, oral communication). The age of the presumed salt layer is Jurassic, correlative with the Louann and Salinas salt of the northern gulf provinces and Isthmian Salt Embayment, respectively. Of the twelve sites of Leg 10 from which core material was obtained, five showed evidence of increase in intersti1 Contribution No. 2919 of the Woods Hole Oceanographic Institution. Publication approved by the Director, U.S.G.S. tial salinity and chlorinity, while four showed no significant increase in salinity with depth. Three sites (90, 91, and 97) showed slight increases in chlorinity and salinity, but not sufficiently large to permit any conclusions about the presence of salt at depth. Analytical methods follow those employed in previous leg reports by the Woods Hole group. The major and minor element pore water data are given in Tables 1 and 2 respectively. We should point out that there is a possibility of loss of alkalinity and calcium during transport of samples to this laboratory owing to precipitation of calcium carbonate in the heat-sealed plastic pipes used to store pore fluid squeezed on board ship. This may account for some erratically low values of calcium in the upper parts of the sediment column, although other elements are not appreciably affected. Another factor to be considered is an increase in potassium values and decrease in magnesium values for samples that were seqeezed on board ship at a presumably higher than in situ temperature. Based on the results of Sayles et al. (in press) for sediments from the Caribbean Sea, the expected change in concentration would be up to +0.05 g/kg for K and —0.07 g/kg for Mg on warming from 4° to 23° C. Warming of the samples before squeezing has also been shown to substantially increase silica concentration in interstitial water (Fanning and Pilson, 1971; Sayles et al., in press), and the values shown in Table 2 are therefore likely to be too high. Special laboratory difficulties (in Leg 10 samples) probably account for the poorer than usual agreement between cation and anion sums (Table 1). We do not however, believe that the artifacts discussed above materially affect the major trends in ionic composition.

Leg 10 interstitial water analyses provide new indications of the distribution of rock salt beneath the floor of the Gulf of Mexico, both confirming areas previously indicated to be underlain by salt bodies and extending evidence of salt distribution to seismically featureless areas in the Sigsbee Knolls trend and Isthmian Embayment. The criterion for presence of salt at depth is a consistent increase in interstitial salinity and chlorinity with depth. Site 86, on the northern margin of the Yucatan Platform, provided no evidence of salt at depth. Thus, our data tend to rule out the suggestion of Antoine and Bryant (1969) that the Sigsbee Knolls salt was squeezed out from beneath the Yucatan Scarp. Cores from Sites 90 and 91, in the central Sigsbee Deep, were not obtained from a great enough depth to yield definite evidence for the presence of buried salt. INTRODUCTION Materials cored at Leg 10 sites consist largely of rapidly deposited Tertiary marly sediments. One of the chief areas of interest in the Gulf of Mexico is the documented presence of salt at depth, both under the northern margin of the gulf (Uchupi and Emery, 1968; Murray, 1966; Paine and Meyerhoff, 1970; Lehner, 1969) and in the Sigsbee Knolls area (Burk et al., 1969, and references cited therein). Study of pore fluids in DSDP Leg 1 cores (Manheim and Sayles, 1970, and references cited therein) extended the previous study of pore fluids from the northern margin of the gulf (Manheim and BischofF, 1969) and demonstrated that diffusion of salt establishes a characteristic salinity and chlorinity gradient in sediments that lie above rock salt. Where enough geologic time has elapsed, the presence of salt more than 3 km below the lowest penetrated horizon can be established by pore fluid studies. This happened in the case of Site 3, where the hole bottomed at 620 meters, while seismic basement was estimated to be 4000 meters below the sea floor (J.L. Worzel, oral communication). The age of the presumed salt layer is Jurassic, correlative with the Louann and Salinas salt of the northern gulf provinces and Isthmian Salt Embayment, respectively. Of the twelve sites of Leg 10 from which core material was obtained, five showed evidence of increase in intersti1 Contribution No. 2919 of the Woods Hole Oceanographic Institution. Publication approved by the Director, U.S.G.S. tial salinity and chlorinity, while four showed no significant increase in salinity with depth. Three sites (90, 91, and 97) showed slight increases in chlorinity and salinity, but not sufficiently large to permit any conclusions about the presence of salt at depth. Analytical methods follow those employed in previous leg reports by the Woods Hole group. The major and minor element pore water data are given in Tables 1 and 2 respectively. We should point out that there is a possibility of loss of alkalinity and calcium during transport of samples to this laboratory owing to precipitation of calcium carbonate in the heat-sealed plastic pipes used to store pore fluid squeezed on board ship. This may account for some erratically low values of calcium in the upper parts of the sediment column, although other elements are not appreciably affected. Another factor to be considered is an increase in potassium values and decrease in magnesium values for samples that were seqeezed on board ship at a presumably higher than in situ temperature. Based on the results of Sayles et al. (in press) for sediments from the Caribbean Sea, the expected change in concentration would be up to +0.05 g/kg for K and —0.07 g/kg for Mg on warming from 4° to 23° C. Warming of the samples before squeezing has also been shown to substantially increase silica concentration in interstitial water (Fanning and Pilson, 1971; Sayles et al., in press), and the values shown in Table 2 are therefore likely to be too high. Special laboratory difficulties (in Leg 10 samples) probably account for the poorer than usual agreement between cation and anion sums (Table 1). We do not however, believe that the artifacts discussed above materially affect the major trends in ionic composition.

Changes in salinity in groundwater and surface water in the Arkansas River valley of southeastern Colorado are primarily related to irrigation practices. A solute transport model was applied to an 11‐mile reach of the valley to compute salinity changes in response to spatially and temporally varying stresses. The model was calibrated in 1973 using detailed field measurements made during 1971 and 1972. In 1973 the calibrated model was used to predict that a gradual long‐term increase in groundwater salinity of about 2–3% per year would occur if the observed irrigation practices continued. The study area was resampled during the winter of 1982 to help evaluate if any long‐term changes in salinity are actually occurring. Nonparametric and parametric statistical tests were used to help assess the significance of observed changes in groundwater salinity. These tests indicate that a statistically significant increase in salinity occurred between the winters of 1971 and 1972 (the model calibration period). However, a comparison of the winter 1972 and winter 1982 data indicates that no significant net change in salinity has occurred during this 10‐year period. An analysis of the few available historical data (1895, 1923, 1959–1961, and 1964) supports the hypothesis that groundwater salinity in this irrigated area has reached a long‐term dynamic equilibrium in response to irrigation practices. The model predictions of long‐term salinity increases were invalid probably because the calibration period occurred during a short‐term annual trend of increasing salinity in the river (and hence in leaky irrigation canals and in applied irrigation water), which was not representative of the long‐term trend.

Purpose. The growth of surface water salinity in urban landscapes due to both anthropogenic factors and gradual global climate change is studied. The influence of various factors is analyzed, according to the data that have been published in recent years. Methodology. Statistics on the state of surface waters, acidity of precipitation and the quality of drinking water in Ukraine show that in the southern and south-eastern regions the situation is becoming threatening. As Kharkiv region is one of the three leaders in the demands for drinking and technical water among the regions of Ukraine, the analysis of water sources in the Kharkiv region is carried out. Results. The results of measurements of chemical parameters of water samples from different parts of the river system Kharkiv-Lopan-Uda in Kharkiv: at the entrance of each river into the city, at industrial sites, at the mouth and at the exit of the river Uda from the city. It is shown that in recent years there has been a steady increase in the total concentration of salts. The rivers Kharkiv, Lopan and Udy at the entrance to the territory of Kharkiv have a fairly low content of sulfates, chlorides, magnesium and calcium, but after the passage of industrial areas to the city center there is a significant increase in salinity and water hardness. Our own data are in good agreement with the results of water quality tests by other laboratories. Thus, in the context of global climate change, the salt content in the river system Kharkiv-Lopan-Uda increases, which significantly affects the system of groundwater and drinking water. Originality. In the research the detailed data on concentrations of the ions Cl-, SO42-, Са++, Mg++ in 12 locations along the three rivers (Kharkiv, Lopan, Udy) of the complex river sys- tem in different seasons (spring, summer, autumn) have been studied and compared to similar data from open sources. The statistical dependencies of the relative concentrations during the last 40 years have been analyzed. Practical meaning. It is determined that the concentrations of some ions demonstrate the monotones growth during the last years, while others varies non-monotonously. Therefore, the influence of different natural and antropogenic factors on global gradual increase in the river water salinity can be quantified by a complex index weighted over a set of concentrations. Conclusions. The results of the literature and measurement data analysis confirmed that with increasing anthropogenic factors and global climate change, the level of surface and groundwater in the urban area of Kharkiv region will decrease and their quality will deteriorate due to increased salinity, calcification and levels of a number of pollutants, which requires further detailed study of this complex problem, permanent data monitoring and systematization in the open access sources of information, which can be processed both by statistical methods and with the help of new system dynamic approaches for the dynamical systems with the ability to control and stabilize the system.

Red mud is highly alkaline (pH 13), saline and can contain elevated concentrations of several potentially toxic elements (e.g. Al, As, Mo and V). Release of up to 1 million m(3) of bauxite residue (red mud) suspension from the Ajka repository, western Hungary, caused large-scale contamination of downstream rivers and floodplains. There is now concern about the potential leaching of toxic metal(loid)s from the red mud as some have enhanced solubility at high pH. This study investigated the impact of red mud addition to three different Hungarian soils with respect to trace element solubility and soil geochemistry. The effectiveness of gypsum amendment for the rehabilitation of red mud-contaminated soils was also examined. Red mud addition to soils caused a pH increase, proportional to red mud addition, of up to 4 pH units (e.g. pH 7→11). Increasing red mud addition also led to significant increases in salinity, dissolved organic carbon and aqueous trace element concentrations. However, the response was highly soil specific and one of the soils tested buffered pH to around pH 8.5 even with the highest red mud loading tested (33% w/w); experiments using this soil also had much lower aqueous Al, As and V concentrations. Gypsum addition to soil/red mud mixtures, even at relatively low concentrations (1% w/w), was sufficient to buffer experimental pH to 7.5-8.5. This effect was attributed to the reaction of Ca(2+) supplied by the gypsum with OH(-) and carbonate from the red mud to precipitate calcite. The lowered pH enhanced trace element sorption and largely inhibited the release of Al, As and V. Mo concentrations, however, were largely unaffected by gypsum induced pH buffering due to the greater solubility of Mo (as molybdate) at circumneutral pH. Gypsum addition also leads to significantly higher porewater salinities, and column experiments demonstrated that this increase in total dissolved solids persisted even after 25 pore volume replacements. Gypsum addition could therefore provide a cheaper alternative to recovery (dig and dump) for the treatment of red mud-affected soils. The observed inhibition of trace metal release within red mud-affected soils was relatively insensitive to either the percentage of red mud or gypsum present, making the treatment easy to apply. However, there is risk that over-application of gypsum could lead to detrimental long-term increases in soil salinity.

Despite not having been fully recognized, the cryptic northern refugia of temperate forest vegetation in Central and Western Europe are one of the most important in the Holocene history of the vegetation on the subcontinent. We have studied a forest grass Bromus benekenii in 39 populations in Central, Western and Southern Europe with the use of PCR-ISSR fingerprinting. The indices of genetic population diversity, multivariate, and Bayesian analyses, supplemented with species distribution modelling have enabled at least three putative cryptic northern refugial areas to be recognized: in Western Europe—the Central and Rhenish Massifs, in Central Europe—the Bohemia–Moravia region and in the Eastern/Western Carpathians. Central Poland is the regional genetic melting-pot where several migratory routes might have met. Southern Poland had a different postglacial history and was under the influence of an Eastern/Western Carpathian cryptic refugium. More forest species should be checked in a west–east gradient in Europe to corroborate the hypothesis on the Western European glacial refugia.

Territories and economies of hunter–gatherer groups during the last glacial maximum in Europe

The Yalgorup lakes, a groundwater-fed system in south-western Australia recognized as a Ramsar wetland, hold significant scientific and conservation value due to the presence of a unique range of lake systems, resident waterfowl and, on the eastern shore of Lake Clifton, the presence of the only thrombolite reef in the southern hemisphere. Recent concern over changing physico-chemical conditions in the lakes, particularly an increase in salinity, prompted this study: the current status of the inherent thrombolite community is unknown. Salinity, total phosphorous (TP), phosphate, total nitrogen (TN), nitrate, chlorophyll-a and relative abundance of the thrombolite microflora were measured in Lake Clifton to analyse changing conditions in this lake and to determine the effect of these water parameters on the thrombolite community. Comparisons with historical data revealed a significant increase in salinity since 1985 and a possible increase in phosphorus concentrations in the lake in the recent decade, although historical nutrient data are rather sparse. The increased salinity may be due to concentration of lake water through a combination of high evaporation, long-term reduction in rainfall and increased groundwater abstraction. Comparison of the composition of the thrombolite community with historical data indicates a large reduction in relative abundance of Scytonema sp. and other filamentous cyanobacterial species, which are believed to be fundamental for the thrombolite structure. It is concluded the changing physico-chemical environment of the Yalgorup Lakes may have led to the decline in important genera in the thrombolite community; however, the mechanisms underlying this change remain unknown.

This study is devoted to the investigation of Azygia (Digenea: Azygiidae) species diversity using classical morphological, recent molecular tools (28S rRNA and cox1 mtDNA for genetic-based inference) and robust statistical techniques (Principal component analysis, PCA). The analysis revealed that the genus Azygia included four valid species: A. lucii, A. longa, A. hwangtsiyui, and A. sibirica n. sp. The distribution of the type species A. lucii was confirmed in the largest Russian rivers: the Volga and the Ob. The worms isolated from Perccottus glenii were determined as the Chinese species A. hwangtsiyui, according to the genetic data for the cox1 mtDNA gene, at 1.32–1.56%. The new species, Azygia sibirica n. sp, was described from Esox lucius in the Ob River and differentiated from the type species A. lucii by the smaller ovary, testes and prostatic sac, wider body, very narrow pharyngeal lumen and form of anterior margin of ovary. In addition, multivariate analysis and three methods for species delimitation (ABGD, GMYC, bPTP) showed the subdivision of A. lucii and A. sibirica n. sp. into two separate groups, one from the Volga River and another from the Ob River, respectively. To conclude, A. lucii infects Esox lucius in the western (European part of Russia, the Volga River basin), and northern (Western Siberia, the Ob River basin) parts of Russia; A. sibirica n. sp. has also been found to infect Esox lucius in the Ob River, while A. hwangtsiyui infects Perccottus glenii in the South of the Russian Far East (the Artymovka River basin).