Особенности микробиологического состава вод реки Раздольной (южное Приморье)

Произведена оценка численности и ее сезонной изменчивости для различных индикаторных групп микроорганизмов в поверхностных водах р. Раздольной. Результаты исследования показали, что они подвержены высокому комплексному органическому, техногенному и микробиологическому загрязнению. В поверхностных водах р. Раздольной были выявлены эколого-трофические группы микроорганизмов, которые принимали участие в очищении вод реки. Однако из-за постоянного притока сточных вод бактерии не успевали перерабатывать поступающее органическое вещество, что указывает на неспособность данной экосистемы к полному самоочищению. Согласно классификатору качества вод, воды р. Раздольной по микробиологическим показателям отнесены к грязным в летний сезон, к загрязненным в весенний и осенний периоды и к чистым в зимний сезон

Seasonal hydrological and hydrochemical surveys in the Voevoda Bay (Amur Bay, Japan Sea)

Hydrological and hydrochemical surveys were conducted in the Voevoda Bay in May, August, and October, 2011 and February, 2012, in total 140 stations. Free water exchange of the bay with the Amur Bay is observed, with exception of its inner bights Kruglaya and Melkovodnaya. The water exchange is maintained by anticyclonic circulation with the inflow along the southern coast and outflow along the northern coast of the Voyevoda Bay. However, the opposite cyclonic circulation is observed in the Melkovodanaya Bight because of its coastal line patterns and fresh water discharge by the river. Dissolved oxygen content and partial pressure of CO2 in the bay waters are determined mostly by intensive processes of production and destruction of organic matter. There are three main groups of primary producers there, as diatom algae, sea grass Zostera marina , and periphyton. Specific chemical regime is formed in the Melkovodnaya Bight, in particular in winter when primary production depends on the ice cover and is driven by variations of photosynthetically active radiation passed through the ice. Seasonal variability of production-destruction processes intensity is discussed on the data of chemical parameters changes

Gold in Ferromanganese Deposits from the NW Pacific

Ferromanganese crusts from four different areas of the North-West Pacific Ocean—the Detroit (northern part of the Imperial Ridge) guyot, the Zubov (Marshall Islands) guyot, the “Gummi Bear” seamount (an intraplate volcano near the Krusenstern FZ), and Belyaevsky volcano (the Sea of Japan)—were studied. Samples from the Detroit and Zubov guyots and the “Gummi Bear” seamount have similar chemical and mineral compositions of hydrogenetic cobalt-rich ferromanganese crusts. Crust from the Sea of Japan seems to reflect a hydrothermal influence. The gold content in most samples from the Detroit guyot was 68 ppb and from the Zubov guyot varied from 180 to 1390 ppb, which is higher than the average for the Pacific crusts (55 ppb). Gold content in two other samples was less than 10 ppb. Based on the electron microscopic studies, aggregation of gold particles with a size of 680 μm were identified in the Detroit guyot crust. The sizes of the Au particles are up to 10–15 μm, which has not been previously noted. Gold particles similar in morphology and size were also found in the Zubov guyot crust, which is located far from the Detroit guyot. The largest particle of gold (≈60 μm), represented by electrum, was found in the clay substrate from the “Gummi Bear” seamount. The lamellar, rudaceous morphology of the gold particles from the Detroit and Zubov guyots reflects their in situ formation, in contrast to the agglutinated, rounded with traces of dragging gold grain found in the substrate of the sample from the “Gummi Bear” seamount. Three-component (Ag-Au-Cu) gold particles were found in the hydrothermal crust from the Belyaevsky underwater volcano. Grains similar in composition were also found in Co-rich crust. The research results show that the gold was probably added to by hydrothermal fluid in the already-formed hydrogenetic ferromanganese crusts during rejuvenated volcanic stages. Biogeochemical processes may have played a major role in the formation of submicron solid-phase gold particles

The influence of hydrothermal activity during the origin of Co-rich manganese crusts of the N-W Pacific

The distribution of cobalt, vanadium, cadmium and molybdenum in the mineral fractions of the Co-rich manganese crusts (CMC) from Zubov and Govorov Guyots is considered. It is shown that the concentrations of cobalt in the ferrous fraction, and vanadium, cadmium in the manganese fraction indicate the ability of the CMC to record the rejuvenated volcanism in the N-W Pacific

Mineral Phase-Element Associations Based on Sequential Leaching of Ferromanganese Crusts, Amerasia Basin Arctic Ocean

Ferromanganese (FeMn) crusts from Mendeleev Ridge, Chukchi Borderland, and Alpha Ridge, in the Amerasia Basin, Arctic Ocean, are similar based on morphology and chemical composition. The crusts are characterized by a two- to four-layered stratigraphy. The chemical composition of the Arctic crusts differs significantly from hydrogenetic crusts from elsewhere of global ocean by high mean Fe/Mn ratios, high As, Li, V, Sc, and Th concentrations, and high detrital contents. Here, we present element distributions through crust stratigraphic sections and element phase association using several complementary techniques such as SEM-EDS, LA-ICP-MS, and sequential leaching, a widely employed method of element phase association that dissolves mineral phases of different stability step-by-step: Exchangeable cations and Ca carbonates, Mn-oxides, Fe-hydroxides, and residual fraction. Sequential leaching shows that the Arctic crusts have higher contents of most elements characteristic of the aluminosilicate phase than do Pacific crusts. Elements have similar distributions between the hydrogenetic Mn and Fe phases in all the Arctic and Pacific crusts. The main host phases for the elements enriched in the Arctic crusts over Pacific crusts (Li, As, Th, and V) are the Mn-phase for Li and Fe-phase for As, Th, and V; those elements also have higher contents in the residual aluminosilicate phase. Thus, higher concentrations of Li, As, Th, and V likely occur in the dissolved and particulate phases in bottom waters where the Arctic crusts grow, which has been shown to be true for Sc, also highly enriched in the crusts. The phase distributions of elements within the crust layers is mostly consistent among the Arctic crusts, being somewhat different in element concentrations in the residual phase

Sr and Nd isotopes in hydrogenetic ferromanganese crusts from the North Pacific

Актуальность исследования обусловлена необходимостью познания фундаментальной научной проблемы - железомарганцевый рудогенез Мирового океана. Помимо перспективного минерального сырья, морские железомарганцевые образования являются регистраторами условий седиментации в прошлом. Их формирование осуществляется при различных процессах, которые отражены в вещественном и изотопном составе. В настоящее время наименее изученным регионом Тихого океана является его северный сегмент. Цель: изучить изотопный состав Sr и Nd железомарганцевых корок северной Пацифики, формирующихся в условиях низкого терригенного потока. Методы: литолого-морфогенетический; рентгеноструктурный - определение минерального состава; масс- спектрометрический - определение химического и изотопного состава. Результаты. Исследованы железомарганцевые образования гайотов северной части Императорского хребта (Детройт, Сьюзей, Ханзей) и разломных зон Амлия, Рат и Стейлмейт, а также гайота Вулканолог (Магеллановы горы) в качестве сравнительного материала. На основании текстурно-структурных и минералого-геохимических особенностей изученные железомарганцевые образования отнесены к гидрогенным железомарганцевым коркам. Изотопный состав стронция изученных образцов находится в интервале от 0,70797 до 0,70919 (среднее 0,70885). При этом содержание стронция изменяется почти в три раза - от 660 до 1700 г/т. Зависимости изотопного состава от концентрации Sr не отмечается. Смещение величины отношения 87Sr/86Sr происходит к его значениям, характерным для вулканических пород, что является отражением высокого количества кварц-плагиоклазовой примеси в образце. Изотопный состав неодима в пересчете на εNd варьирует в интервале от -3,5 до -3,0, что соответствует современному значению глубинной воды северной Пацифики. Повышение значения εNd до -2,3 соответствует пробе с максимальной аллотигенной примесью. Минимальное значение величины εNd (-4,4) установлено в подошвенном слое железомарганцевой корки гайота Ханзей. Такое значение соответствует миоценовой глубинной воде северной Пацифики. Это является основанием полагать, что в миоцене на формирование вещественного состава железомарганцевых корок северной Пацифики оказывали влияние глубинные атлантические воды, поступающие через Панамский пролив. Прекращение их поставки в Тихий океан произошло, вероятно, пять млн лет назад.The relevance of the study is caused by the need to get knowledge of the fundamental scientific problem - the ferromanganese precipitation of the World Ocean. Marine ferromanganese deposits are records of sedimentation conditions in the past as well as promising mineral raw materials. Their formation is carried out under various processes, which are reflected in the bulk and isotopic composition of ferromanganese deposits. Currently, the least studied region of the Pacific Ocean is its northern segment. The main aim of the research is to study Sr and Nd isotopic composition of the ferromanganese crusts from the Norther Pacific, formed under low detrital influx. Methods: litho-morphology; x-ray diffraction - determination of the mineral composition; mass spectrometric - determination of the chemical and isotopic composition. Results. Ferromanganese deposits of the guyots of the northern part of the Imperial Range (Detroit, Suzei, Hanzei) and the Amliya, Rat and Stailmate fracture zones, as well as the Vulkanolog Guyot (Magellan Seamounts), as a comparative material, were studied. Based on the mineralogical and geochemical bulk compositions, the studied ferromanganese deposits are classified as hydrogenetic ferromanganese crusts. The strontium isotopic composition of the studied samples is in the range from 0,70797 to 0,70919 (average 0,70885), with most of the samples concentrated at 0,709. At the same time, the content of strontium changes almost three times from 660 to 1700 ppm. The dependence of the isotopic composition on the concentration is not observed. The displacement of 87Sr/86Sr occurs towards volcanic rocks, which reflects the high amount of quartz-plagioclase admixture in the sample. The isotopic composition of neodymium, in terms of εNd, varies in the range from -3,5 to -3,0, which corresponds to the modern deep seawater of the North Pacific. An increase in εNd to -2,3 corresponds to a sample with the maximum terrigenous admixture. The minimum value of εNd (-4,4) was found in the bottom layer of the ferromanganese crust from the Hanzei Guyot. This value corresponds to the Miocene North Pacific Deep water. This is a reason to believe that in the Miocene the formation of the bulk composition of the North Pacific ferromanganese crusts was under North Atlantic Deep Waters entering through the Panama Gateway. The end of North Atlantic Deep Waters delivery to the Pacific was finished about five million years ago

Extraction-atomic-absorption determination of gold in marine ferromanganese formations after its concentration with dibutyl sulphide in toluene

Актуальность исследования обусловлена необходимостью наработки методических решений по количественному определению содержания золота в железомарганцевых образованиях и других геологических объектах в связи с существующими здесь химико-аналитическими трудностями и недостаточным количеством стандартных образцов состава железомарганцевых образований с надежно аттестованным содержанием в них золота. Цель: проверка применимости методики экстракции золота с использованием нефтесульфидов (дибутилсульфида в толуоле) к определению золота в железомарганцевых образованиях с электротермическим атомно-абсорбционным окончанием, наряду с методикой извлечения золота его соосаждением с теллуром. Объекты: пробы железомарганцевых образований из различных районов северной части Тихого океана, а также российский стандартный образец состава с аттестованным содержанием золота ООПЕ 603 (СДО-6) и стандарт Геологической службы США NOD-A-1. Методы. Проведено концентрирование золота при его определении в железомарганцевых образованиях по методикам экстракции дибутилсульфидом в толуоле и соосаждением с теллуром и электротермическим атомно-абсорбционным анализом. Обработка полученных результатов проведена с применением методов математической статистики. Результаты. Методика экстракции золота с дибутилсульфидом в толуоле показала свое преимущество для целей анализа железомарганцевых образований, по сравнению с процедурой соосаждения с теллуром, в связи с ее высокой селективностью, позволяющей избавляться от влияния матричных компонентов, в первую очередь железа, формирующего мешающее наложение спектральных линий при атомно-абсорбционном определении золота. Методика экстракции золота с дибутилсульфидом была апробирована для анализа образцов железомарганцевых образований из различных районов северной части Тихого океана, а также стандартных образцов состава железомарганцевых образований - российском ООПЕ 603 (СДО-6) и американском стандарте NOD-A-1. Использование воздушносухой навески 2 г образца дало удовлетворительный результат при анализе стандартного образца СДО-6 с аттестованным содержанием золота 10±6 нг/г, но не позволило успешно проанализировать образец NOD-A-1, для которого были получены невоспроизводимые результаты. В этой связи для определения в данном стандарте золота рекомендуется использование еще больших навесок. Атомно-абсорбционное определение золота в изученных образцах железомарганцевых образований по предлагаемой методике показало результаты, отвечающие требованиям геохимического анализа, в том числе и по сравнению с ИСП-МС методом. Однако проведенное ранее электронно-микроскопическое исследование железомарганцевых корок северо-западной части Тихого океана выявило присутствие в них частиц самородного золота, что может, в свою очередь, вызывать методические сложности в процессе отбора представительной пробы и в процедуре подготовки образцов железомарганцевых образований к анализу.The relevance of the study is caused by the need to develop methodological solutions for the quantitative determination of gold content in ferromanganese formations and other geological objects due to the chemical and analytical difficulties that exist here and the insufficient number of certified reference materials of ferromanganese formations with a reliably certified gold content in them. The main aim is verification of the applicability of the gold extraction technique using petroleum sulfides (dibutyl sulfide in toluene) f or determining gold in ferromanganese formations with electrothermal atomic absorption termination, along with the gold extraction method by its co-precipitation with tellurium. Objects: samples of ferromanganese formations from various regions of the North Pacific Ocean, as well as the Russian certified reference materials with a certified gold content OOPE 603 (SDO-6) and the USGS standard NOD-A-1. Methods. Gold was concentrated during its determination in ferromanganese formations by the methods of extraction with dibutyl sulfide in toluene and co-precipitation with tellurium and electrothermal atomic absorption analysis. Processing of the obtained results was carried out using the methods of mathematical statistics. Results. The method of gold extraction with dibutyl sulfide in toluene has shown its advantage for the purposes of analysis of ferroma nganese formations in comparison with the procedure of co-precipitation with tellurium, due to its high selectivity, which makes it possible to get rid of the influence of matrix components, primarily iron, which forms an interfering superposition of spectral lines during atomic absorption determination of gold. The technique of gold extraction with dibutyl sulfide was tested for the analysis of ferromanganese formations samples from various regions of the North Pacific Ocean, as well as for the analysis of ferromanganese formations samples - the Russian OOPE 603 (SDO-6) and the American standard NOD-A-1. The use of an air-dry sample of 2 g of the sample gave a satisfactory result in the analysis of the standard sample SDO-6, with a certified gold content of 10±6 ng/g, but did not allow successful analysis of the NOD-A-1 sample, for which irreproducible results were obtained. In this regard, the use of even larger weights is recommended for defining gold in this standard. Atomic absorption determination of gold in the studied ferromanganese formations samples using the proposed method gave results that meet the requirements of geochemical analysis, including in comparison with the ICP-MS method. However, an earlier electron microscopic study of ferromanganese crusts in the northwestern part of the Pacific Ocean showed the presence of native gold particles in them, which, in its turn, can cause methodological difficulties in the process of taking a representative sample and d the procedure for preparing ferromanganese formations samples for analysis

Production patterns in the estuary of the Razdolnaya River in period of freezing

Light conditions and nutrients supply, as factors of primary production, are considered for the Razdolnaya River estuary in period of freezing (January-March). Water samples were collected at the water surface and at the bottom for measuring of salinity and concentrations of chlorophyll (Chl), phosphate, nitrite, nitrate, ammonium, and silicate. Profiles of water temperature, conductivity, Chl fluorescence, and turbidity were measured in situ by CTD-probe RBR XR-620; besides, vertical attenuation of PAR was measured at each station. The internal estuary (salinity 5 FTU) and high concentration of humine substances (up to 2 mgC/l) in the river waters. The ice cover lowered light intensity in the river water, too. In the zone close to the river bar with salinity 1-25 ‰, Chl concentration was 0.4-1.7 mg/m3 irrespective of salinity. DIN (dissolved inorganic nitrogen) and DISi (dissolved inorganic silicon) had conservative behaviour in this zone, the DISi : DIN ratio was ≈ 0.7-1.1.These features indicate an absence of significant production or destruction of organic matter in the internal estuary. However, intensive removal of dissolved inorganic phosphorus (DIP) (up to 80 %) was observed in this zone, that’s why the extraordinary high DIN : DIP ratio was observed under salinity 5-20 ‰ (up to 200 : 1, though the usual DIN : DIP ratio in the river water is close to Redfild ratio: DIN : DIP = (21-27) : 1). In the external estuary (salinity15-32 ‰), the water became more transparent ( kd = 0.5-0.3 m-1; zeu ≈ 9-15 m) and both chlorophyll concentration and dissolved oxygen content became higher (Chl up to 20 mg/m3, DO up to 500 mM/kg) as the result of high primary production, whereas nutrients concentrations became lower: DIP were completely removed and DIN and DISi retained 10-25 % of their initial values in the river water. The primary production value was evaluated by two ways: on the data of light intensity and on the data of nutrients removal. The light conditions in the internal estuary in February-March corresponded to the value 20-80 mgC/m2d which declines in 6-13 times and 50-100 times (close to zero) under the ice and under the ice with snow, respectively. In the external estuary, the light conditions in March corresponded to the value 300-600 mgC/m2d in the areas without ice and to the value lower in 6-13 times under the ice. The nutrients removal corresponded to the primary production value ≈ 200-400 mgC/m2d in the external estuary, irrespective of ice cover, that is close to the previous estimation by light conditions. So, the primary production in the Razdolnaya River estuary changes in winter in the range from 0 to 500 mgC/m2d, increasing seaward, the ice and snow are the factors of its limitation by light

Seasonal Hypoxia of Amursky Bay in the Japan Sea: Formation and Destruction

Based on detailed hydrological and hydrochemical surveys carried out in each of the four seasons of 2008, Amursky Bay in the north west quadrant of the Japan Sea was found to experience seasonal hypoxia. The primary process of hypoxia formation is a microbiological degradation of the ¡§excess¡¨ amount of diatoms under rather low photosynthetic active radiation in bottom layer and weak water dynamics. The microbiological decay of dead diatoms under light deficient conditions intensively consumes dissolved oxygen and produces phosphates, ammonium, silicates, and dissolved inorganic carbon. Existence of a phytoplankton ¡§excess¡¨ is caused by phytoplankton bloom resulting from nutrient pulses into Amursky Bay. There are two main sources of these nutrients: the waste waters of Vladivostok city and discharge from Razdolnaya River. The river delivers more than two times the amount of nutrients than the waste waters of Vladivostok. It is suggested that the phytoplankton ¡§excess¡¨ might be caused by an enhanced supply of nutrients delivered into the surface layer resulting from the increased discharge of the river on a short time scale. Our data suggest that hypoxia is seasonal, with a peak at the end of summer. The upwelling of the Japan Sea water in the beginning of the fall season and its advection across the shelf is the primary process by which the hypoxia is destroyed. During the winter, strong vertical mixing due to termohaline convection makes the water column uniform and brings more oxygen into the water along with high primary production under the ice. Thus, during the winter season, the ecosystem of Amursky Bay recovers completely