RESULTS OF NEW STUDIES OF EARLY NEOLITHIC LAYERS AT RAKUSHECHNYY YAR (ROSTOV REGION)

Ракушечный Яр - уникальный стратифицированный памятник VII/VI тыс. до н. э. - раннего Средневековья - характеризуется сложной стратиграфией и палеорельефом, наличием погребенных почв и культурных слоев. Планомерные раскопки памятника проводились в 1960-1970 гг. и возобновлены в 2008 г. В результате комплексных археологических и геологических исследований выявлены особенности культурных слоев, позволившие выстроить микрохронологию этого памятника, где отдельные слои формировались за очень короткое время. Ракушечный Яр представляет свидетельства разновременного и последовательного заселения человеком прибрежной зоны. Раскопанные части стоянок, возможно, были специализированными местами использования водных ресурсов. Ранненеолитическое поселение в непосредственной близости от озера, возникшего примерно в сер. VIII тыс. до н. э., появилось около 5600 л. до н. э. В рамках отдельных горизонтов отмечены платформы и/или кучи раковин Unio и Viviparus, перекрытые тонкими (1-3 см) прослойками песка и суглинка и мощным слоем белого стерильного аллювиального песка. Такая последовательность отложений могла возникнуть в прибрежной озерной зоне во время трансгрессий и регрессий. Датировки отдельных слоев указывают на узкий хронологический интервал их сложения, что позволяет предполагать высокий уровень минеральных отложений в озерной котловине. По всей видимости, накопление (около 2 м) ранненеолитических слоев происходило в течение нескольких десятилетий. В статье будут рассмотрены особенности образования культурных и литологических слоев для временного среза раннего неолита. Rakushechnyy Yar is a unique stratified site dating to 7000-6000 BC characterized by complex stratigraphy, presence of buried soils and occupation layers. Consistent excavations of the site were first carried out in 1960-1970 and were then resumed in 2008. Comprehensive geoarchaeological studies helped examine specific traits of its occupation layers providing insight into microchronology of the site where some layers were formed during a very short period of time. Rakushechnyy Yar contains evidence of consistent human occupation of the littoral area in different periods of time. Most likely, the excavated sections of the sites were specialized places where water resources were used. The Early Eneolithic settlement near the lake that had been formed around mid-8th mill. BC appeared around 5600 BC. Platforms and/or bunches of Unio and Viviparus shells overlain with thin (1-3 cm) sand and loam layers and a thick layer of white sterile alluvial sand were recorded in some horizons. This sequence of deposits could occur in the littoral lacustrine area during transgressions and regressions. Dating of several layers point to a narrow chronological interval of their formation suggesting a high level of minerogenetic deposits in the lake basin. Apparently, it took several decades of these minerogenetic deposits of the Early Neolithic layers (around 2 m thick) to form.

Os carcharhiniformes (cCondrichthyes, Neoselachii) da Bacia de Alvalade (Portugal)

The uppermost Miocene, Esbarrondadoiro Formation (Alvalade basin, Portugal) yielded more than 10 thousandSelachian teeth at Santa Margarida, Esbarrondadoiro and Vale de Zebro outcrops. Forty-five taxa were identifiedbelonging to the orders Hexanchiformes, Squaliformes, Lamniformes, Carcharhiniformes, Torpediniformes and Myliobatiformes. The Carcharhiniformes make up about 40% of the selachian fauna that has been identified in the studiedarea. The different distribution of the Carcharhiniformes (as well as that of the other orders) by the three sitespoints out to distinct environments in the corresponding areas: Esbarrondadoiro indicates relatively deeper, ratherstill waters; Santa Margarida represents a very littoral area and rough waters; while Vale de Zebro was a (probablyinner) part of a gulf with muddy bottoms. At the Alvalade Basin localities there are several “temperate” elements that still are present in Portuguese waters. However the high frequence of Carcharhinus, a genus that is scarce at present off Portugal, indicates waters somewhatwarmer than today’s but less warm than during Tortonian times. This is corroborated by the large number of Dasyatisspecies and the rarity of Raja. We may conclude that moderately warm (less warm than during Tortonian, but warmerthan today’s) waters predominated in the Alvalade Basin close by the end of Miocene. The scarcity of pelagic forms and especially of the larger pelagic predators points out to a quite narrow gulf and not to an open Atlantic front. The faunal differences between the Tortonian near Lisbon and the Messinian of the Alvalade Basin also indicate a rather confined gulf.

Water Exchanges and Phosphorus Flux between a Reservoir and Eutrophic Littoral Zone

HighlightsConvective currents led to hydraulic flux and transport of P between bottom and surface waters of the littoral zone.Hydraulic flux was primarily into the bottom of the cove and out of the cove along the surface.Eutrophic littoral areas are a significant source of P to the photic zone of reservoirs, supporting algal growth.Abstract. Eutrophication of surface waters is defined by excessive algal growth, with consequences for drinking water treatment. The sources of phosphorus (P) in southern U.S. reservoirs that fuel peak algal productivity in late summer are still not fully understood. One potential source is reservoir littoral zones, which have been described as the most productive zone of a waterbody. A shallow cove named Granny Hollow in Beaver Lake, northwest Arkansas, was selected as an isolated and semi-controlled location to measure and model sources of P and its transport in a littoral area for the month of July 2018. Hydraulic and P fluxes between the reservoir and littoral area were quantified through field measurements and a 3D lake model. In quantifying hydraulic flux for the month of July, the model indicated that water tended to move into the cove along the bottom and out along the top, with a net hydraulic flux out of the cove of -723,000 m3. Peak surface velocity in the cove averaged 2.09 cm s-1 for the month of July, while peak bottom velocity was 1.29 cm s-1. Diurnally, water movement switched directions, moving out of the cove along the surface during differential heating and into the cove along the surface during differential cooling due to thermoconvective flow. During differential heating, the water velocity and hydraulic flux to the main reservoir channel along the surface of the cove were greater than the velocity and flux in the opposite direction during differential cooling. The sources of P within the cove during July included P released from bottom sediments within the cove and littoral zone and transport of P from the reservoir channel to the cove. Transport of P from the main reservoir into the cove was a result of thermoconvective flow. During differential heating, bottom waters from the main reservoir channel were transported to the surface within the littoral zone by thermoconvective currents flowing upslope from deeper to shallower waters. This resulted in P exchange between the reservoir and littoral area and is significant because it represents movement of P from the bottom of the reservoir upward into the photic zone, where it can be used for algal productivity. During July 2018, it was estimated that 13.3 kg of P were transported from the bottom of the cove to the surface by convective currents and subsequently out of the cove. This study shows that eutrophic coves represent a significant source of P to the reservoir and more importantly to the photic zone, supporting algal growth. Keywords: 3D reservoir model, Eutrophication, Internal loading, Thermoconvective flow.

UUVs support to naval operations

The article analyzes the environmental conditions present in the Black Sea basin and, in this view, the opportunity of employment of unmanned underwater platforms, especially in the contested littoral area. The introductory part of the article is presented up to date UUVs platforms in use with their capabilities and limitations. Then, the paper identifies the shortfalls and opportunities to engage unmanned platforms to operate independently or paired with other undersea, surface, unmanned aerial platforms, or fixed arrays. The closing section analyzes the types of payloads, missions, and capabilities of actual vehicles, and some ways ahead are underlined, especially regarding future sensors, weapons, navigation, and underwater communications capabilities.

Komunitas Fitoplankton di Daerah Litoral Danau Maninjau dan Sungai Ranggeh, Kabupaten Agam Kaitannya dengan Kandungan Nutrien

<p><strong>Phytoplankton Community Relationship with Nutrient Content in the Littoral Areas of Lake Maninjau and Ranggeh River, Agam Regency.</strong><strong> </strong>Phytoplankton in Lake Maninjau is a food source for fish and plankton-eating fish such as Bada fish (<em>Rasbora</em> sp.), Lake Maninjau endemic fish that have high economic value. Nutrients such as nitrogen and phosphorus would be the limiting factors for phytoplankton growth. This observation aims to determine the composition and abundance of phytoplankton to nutrient content in the littoral areas of Maninjau Lake and Ranggeh River. The observations were conducted on April, July, August, September, October, and November 2018 at several observation stations. The results show that there were phytoplankton groups, ie. Chlorophyta (53 species), Bacillariophyta (35 species), Cyanophyta (six species), Euglenophyta (five species), and Dinophyta (two species). The phytoplankton abundance in Maninjau littoral region ranged from 0.07 x 10⁶ - 5.8 x 10⁶individual.L^-1, while in Ranggeh River ranges from 0.0016 x 10⁶ - 2.1 x 10⁶individual.L^-1. In July 2018, the most abundant species was <em>Microcystis aeruginosa</em> (Cyanophyta), in August and September were <em>Synedra ulna</em> (Bacillaryophyta) while in October and November were <em>Cylindrospermopsis raciborskii</em> (Cyanophyta). Based on the diversity index, evenness index and dominance index, the phytoplankton community in the littoral area of Maninjau Lake was unstable compared to Ranggeh River. Principal component analysis showed that the abundance of Cyanophyta in the Maninjau littoral area was influenced by the concentration of phosphorus.</p>

МІКРОФІТОБЕНТОС ЯК БІОІНДИКАТОР ЗМІНИ ГІДРОМОРФОМЕТРИЧНИХ ПАРАМЕТРІВ ВОДНОГО ОБ’ЄКТУ МІСТА КИЄВА

A great number of water bodies within urban areas of Kyiv City are exposed to human impact. Hydrotechnical construction operations alter their morphometric and hydrological parameters, water bodies are contaminated with various inorganic and organic substances etc. Since human impact upon water bodies has diversified, bioindication is a well-established and effective method of assessing water bodies’ ecological status and measuring the rate of their ecosystems’ disturbance. Microphytobenthos is an important element of aquatic ecosystems and is widely used as a reliable biological indicator. While using microphytobenthos as an ecological community, it is required to evaluate the bioindication efficiency of its indicative structural elements, which respond distinctly to changes in anthropogenic factors on the whole and in the degree of human impact upon water bodies of different types. This paper considers the findings of studying microphytobenthos indicative structural element bioindication characteristics – ecological-morphological group of benthic filamentous blue-green algae and their role in forming the respective parameters among benthonts in the littoral area of Opechen Lower Lake, located within Kyiv City residential community. Large-scale hydrotechnical construction operations conducted in the lake in 2019 greatly affected its hydromorphometric parameters by reducing the shallow-water area and disturbing the bottom sediments stability, which resulted in increase of the human load. The objective of the study was to identify key characteristics of the microphytobenthos indicative structural element under conditions of the lake’s hydromorphometric parameters alteration. Benthic algae were sampled with the MB-TE microbenthometer within the littoral area at aquatic-vegetation-free sites located in the lake’s upper and lower sections. Algae sampling and laboratory processing of samples were performed in accordance with the methods generally accepted in hydrobiology. For diatoms identification permanent slides were made with using special high-resolution mounting media. Autochthonous components in microphytobenthos, the indicative ecological-morphological group of benthic filamentous blue-green algae were distinguished proceeding from algae’s association with particular biotopes. In addition to separate characteristics (species richness, number, biomass), a multimetric index was calculated for the benthonts’ indicative group as an arithmetic average of several characteristics. The degree of human impact upon the lake ecosystem was calculated according to the proven method, consisting in distinguishing the total number of the most obvious human factors with consideration taken of their different intensity. The findings of studying the key characteristics of phytomicrobenthos indicative structural element – benthic filamentous blue-green algae in 2018–2019 confirm their high bioindication efficiency and distinct response to hydromorphometric parameters alteration in Opechen Lower Lake. As a consequence of hydromorphometric alterations the share of these algae in the benthonts’ species richness, number and biomass has decreased by half, and the vegetation-period-average multimetric index has lowered by 1.7. This gives the evidence that the conditions for bottom algae vegetation have worsened.

Late Neolithic plant subsistence and farming activities on the southern margins of the Massif Central (France)

Seed and fruit remains from archaeological sites provide the most direct source of evidence on ancient crops and plant food resources. Earlier studies on late Neolithic sites (3500–2200 BC) in the Grands Causses and Hérault valley areas focused on cave and rock-shelter sites. Here, we discuss new and previously published archaeobotanical evidence from open-air settlements, which should be considered as more representative of the standard subsistence and farming economy. Patterns in the data have been analyzed through sample densities, diversity index, taxa ubiquities, and abundance by means of correspondence factor analysis. Contrary to what is assumed in other Western European regions for that period, the available dataset indicates that cereals were consumed and therefore probably cultivated on a regular basis in the Grands Causses and Hérault valley. The range of crops and collected wild fruits was the same in both areas but certain differences existed. As in other regions, einkorn played a significant role during the late Neolithic, but it was more common in the Hérault valley than in the Grands Causses plateaux. On the other hand, the collection of wild fruits seemed to be of more importance in the hinterland than in the littoral area. The more striking difference concerns crop processing activities and the use of glume wheat by-products. They are much more common in the Grands Causses samples.