Quantitative characteristics of zooplankton in the rivers of the Upper Amur Basin, exposed to the effects of placer gold mining

Research conducted in June and September 2020 showed that the species composition of rotifers and lower crustaceans in 17 water courses of the Upper Amur Basin, exposed to the effects of placer gold mining, included 43 species. Most of the water courses were researched for the first time. Based on the environmental and geographic assessment, the prevalent species were widespread and eurytopic. Most parts of the rivers were characterised by low quantitative characteristics (0.01–3.77 × 103 ind. m-3 and 0.06–54.64 mg m-3), which was explained by the hygrological conditions and long-term effects of mining in the river beds. A better productivity (up to 39 × 103 ind. m-3 and 228 mg m-3) was registered in the areas of former excavations in the river beds, with slower water exchange and better conditions for the development of zooplankton.

Sandy soils of forest landscapes of the Amur-Zeya Plain

Historically, soils of the Cambisol group have been recognized as zonal soils of the Upper Amur Basin Region. However, the wide distribution in the territory of the Amur-Zeya Plain of forest soils of light granulometric composition that were formed on loose sedimentary deposits makes it possible to identify an area of Arenosols and Podzols, for the first time described within the study area. The common features in the researched soils are a well-structured thin humus horizon and quartzfeldsparic mineralogical composition causing low intensity of the processes of weathering and metamorphism of mineral substance. The initial stages of biochemical weathering of mineral matter are diagnosed in soils of the Humic Arenosol subgroup. The most intensive processes of weathering and metamorphism of mineral matter are diagnosed in the middle horizons of the Rubic Arenosol group, which is associated with the formation of seasonal frost and the associated cycles of freezing-thawing of the soil profile. In the soils of the Entic Podzol subgroup, the process of iron illuviation is diagnosed, with formation of the maximum accumulation in the lower part of the soil profile at the boundary with the soil-forming rock. Keywords: FOREST SOILS, NEOGENIC SANDS, SOIL MORPHOLOGY, THE UPPER AMUR BASIN REGION

Deglacial records of terrigenous organic matter accumulation off the Yukon and Amur rivers using lignin phenols and long-chain n-alkanes as biomarkers

<p>Anthropogenic climate change has profound impacts on Arctic temperatures, with consequences for Arctic ecosystems and landscapes, and the stability of organic-rich permafrost deposits. When mobilized, these permafrost deposits might release vast amounts of greenhouse gases. We use periods of past rapid warming in the high latitudes as analogues to study the ecological changes and effects on permafrost stability under climate change. We used marine sediment cores from the Bering and Okhotsk Sea continental margins, off the mouths of the Yukon and Amur rivers, to study two types of terrigenous biomarkers, which trace different terrestrial organic carbon (OC) components and transport pathways, and cover the early deglaciation to the early Holocene. The Yukon basin remains within the permafrost-affected region today, whereas the Amur basin changed from being subject to complete permafrost cover during the last glacial to permafrost-free conditions today. </p><p>Vascular plant-derived lignin phenols were analyzed and compared to published n-alkane content data. The carbon- and sediment-normalized contents of the vanillyl phenols (V), syringyl phenols (S), and cinnamyl phenols (C) phenols (Λ8 and Σ8) reflect the content of lignin dominantly transported by river runoff. The C/V and S/V ratios serve to distinguish between woody and non-woody tissues of angiosperms and gymnosperms. The acid to aldehyde ratios of V and S phenols ((Ad/Al)<sub>V</sub> and (Ad/Al)<sub>S</sub>) indicate the degree of lignin degradation. In addition, the ratio of 3,5-dihydroxybenzoic acid to V (3,5Bd/V) likely reflects the wetland extent, while lignin reflects primarily transportation into the marine sediment via surface runoff. In contrast, the n-alkane contents represent primarily terrigenous organic matter eroded from deeper deposits and a second marker for wetland extent via the Paq index. Lignin and n-alkane mass accumulation rates (MAR) can thus be used to reconstruct the mobilization of different carbon pools and the relative timing of the processes leading to their export to the ocean.</p><p>The MAR of biomarkers and the wetland indicators 3,5 Bd/V and Paq start to increase in the Bering Sea sediment during the early deglaciation (19-14.6 ka BP), while no obvious change in lignin MAR in the Okhotsk Sea occurred during this time. We observe distinct peaks of mass accumulation rates, wetland indices and indicators for degradation of lignin (Ad/Al) in both sediment cores during the warm Bølling-Allerød (12.9-14.6 ka BP) and Pre-Boreal (9-11.5 ka BP) intervals, and during the Younger Dryas cold spell (11.5-12.9 ka BP). In contrast, in the Okhotsk Sea, the ratios of S/V and C/V did not change before the Preboreal. </p><p>Our biomarker data suggest that the permafrost in the Yukon basin may have started to be remobilized by inland warming leading to wetland development in the early deglaciation, while the onset of permafrost degradation in the Amur basin occurred during the Preboreal.</p>

Notes on the genus Zaranga Moore with description of a new species in the Zaranga pannosa species group (Lepidoptera: Notodontidae)

The Zaranga pannosa species group of the genus Zaranga Moore, 1884 is reviewed and a new species, Zaranga koreana sp. nov. from Korea, is described based on morphology and genetic data. An updated checklist, key, and ecological and distributional notes to the species are provided. Diagnoses and description are given for the described species. A new locality to Zaranga tukuringra Streltzov et Yakovlev, 2007, is given and this species is considered as narrow local endemic of north-west Amur basin, distributed on the huge distance from other Zapanga species.

MINERALIZATION OF SMALL RIVERS WATER IN THE AMUR REGION

The authors have considered mineralization of small rivers water in the Russian part of the Amur basin. The lowest values are observed in water of the rivers, draining intrusions; the highest ones – in the rivers of the areas with ore occurrences and deposits of polymetals, karst development and mineral water outlets. The maximum salinity is characteristic of the river waters in the urbanized territories.

Salt composition of the waters of the Bureya reservoir

Significance. Significance of the work lies in the need to study the salt composition of the Bureya reservoir water from the beginning of filling, which is important for predicting the water quality of reservoirs in the Amur basin that are to be designed. The objective is to evaluate content of main ions in the water of the Bureya reservoir, and to identify factors determining their spatial and temporal variability. Methods. Hydro/chemical observations in the Bureya reservoir were made from 2003 to 2008 at five plots covering the major part of the water area. Water samples were taken from the surface, middle, and near-bottom horizons in winter, summer, and fall. Water samples were taken from the surface in January, July 2019 in the landslide area and in July 2020 at eight sites in the water body between the landslide and the hydropower dam. Analytical work was carried out according to the methods accepted in hydrochemistry. Materials of the Amur Basin Water Administration for 2005-2019 were used in the work. Results. The content of the main ions in the water of the reservoir during the filling period and the following years was assessed. The dominance of calcium ion among cations and hydrocarbonate ion among anions in the salt composition of water was shown. It is established that the emergence of oxygen deficit in water due to the increased area of flooded forests and reduced water inflow caused the absence of sulfate ion in the reservoir water in autumn and winter 2005. It is shown that staged filling of the reservoir contributed to gradual smoothing of differences in the content of major ions and stabilization of the salt composition of water in the sixth year of filling. In current conditions the content of sodium and potassium ions and chloride ions in the water area of the reservoir is relatively evenly distributed, the highest values of concentrations of calcium and magnesium hydrogen carbonates are observed near the mouth of the Tyrma River. The effect of a large landslide on the content of major ions in the water in 2019-2020 is considered.

The Study of Non-Ferrous Metal Artifacts of the Early Iron Age and Medieval Cultures in the Western Amur Basin

В статье дана морфологическая и количественная характеристика, приведен элементный состав 23 предметов из бронзы, семи из серебра и одного из золота, относящихся к периоду от конца XI—X в. до н.э. до XIII—XV вв. Эти изделия (украшения и отдельные бытовые вещи) относятся курильской, талаканской культурам раннего железного века, михайловской, мохэской и центральноазиатским культурам раннего Средневековья, позднесредневековой культуре дючеров. Элементный анализ бронзовых предметов в Сибирском центре синхротронного и терагерцового излучения на станции локального и сканирующего рентгенофлуоресцентного элементного анализа Института ядерной физики СО РАН показал, что на протяжении примерно 2,5 тыс. лет для их изготовления использовалась в основном оловянно-свинцовая или свинцово-оловянная бронза. Наилучшая сходимость концентраций химических элементов для предметов талаканской и михайловской культур дополнительно свидетельствует о происхождении михайловской культуры от талаканской в результате эволюционного развития последней. Элементный состав серебряных и золотых изделий мохэ из Приамурья выполнен впервые. Он показал высокую пробу серебра и золота, используемых для изготовления ювелирных украшений в раннем Средневековье.

Prospects of freight traffic redirection from rail to water transport through the example of the Amur Basin and coal export transportation

The authors consider the prospects for the development of coal industry and its export potential. The facts of the development of mass transportation of coal by rail in the direction of port transport hubs are given. There is an acute problem of finding new supply channels. In these conditions, it is proposed to start the implementation of a large-scale project for the development of a multimodal transport scheme for the export of coal using river transport. During the 140-day navigation period along the rivers of the Amur Basin in the summer months, a large volume of export coal can be transported to the Far Eastern seaports. Three logistic schemes are proposed and a list of individual subprojects for the development of transport infrastructure for the needs of this project for the transportation of coal from Kuzbass, Krasnoyarsk Territory, Buryatia and Yakutia is given. It is proposed to organize transshipment from railway to river transport in three hubs: Sretensk, Dzhalinda and Verkhnezeisk. Each logistic scheme will be focused on a certain volume of transportation and has its own advantages and disadvantages. The authors invite the transport community to actively discuss this format of transportation due to the urgent need to find ways to develop cargo flows. Each of the three logistic schemes can be considered separately or in combination with others.