Search

The studies of the applicability of simulated precipitation in hydrological calculations and forecasts are presented on the example of the Amur basin rivers. It is shown that the use of simulated precipitation has a positive effect on forecasting rainfall floods in case of a sparse observational network. There is an especially noticeable lack of hydrological and precipitation data on the catchments of the Amur right-bank tributaries located in China (the Songhua River and its tributaries), whose runoff is a significant contributor to the water balance of the Middle and Lower Amur. It is revealed that the catchment-averaged fluctuations in simulated 5-day total precipitation above and below a certain threshold are linked to the temporal variations in water levels at the outlets of the Amur partial catchments. [ABSTRACT FROM AUTHOR]

This study examined the age, growth, and maturation of 1,064 Coregonus ussuriensis individuals that were collected monthly from the middle section of the Amur River, China between 2016 and 2018. The fork length (FL) ranged from 14.9 to 49.1 cm for males and 21.5 to 58.8 cm for females, and the body weight (BW) ranged from 72.6 to 1,348.7 g for males and 107.9 to 2,854.9 g for females. The relationship of BW and FL was expressed as: BW? = 0.0324 × FL2.708; BW? = 0.014 × FL2.963. The sample ages ranged from 2 to 8 years for males and 2 to 9 years for females. We used the von Bertalanffy function based on otolith reading and observed FL data to simulate Coregonus ussuriensis growth, which has been suggested to be similar to that of other Salmonidae fishes. No significant difference in growth was determined between males and females. The monthly gonad somatic index (GSI) value ranged from 0.16% to 1.69% for males and from 0.73% to 16.15% for females, with a peak in November. Additionally, the reproductive staging suggested that the Coregonus ussuriensis spawning season was mainly in November and December. The size at maturity (FL50%) for males and females was 34.9 cm and 37.9 cm respectively, and the corresponding age (T50%) was 4.5 and 5.1, respectively. This study provides basic information for understanding the biological characteristics of Coregonus ussuriensis and should aid in the assessment and management of fishery resources. [ABSTRACT FROM AUTHOR]

GLDAS2.0 provides long‐term fine resolution gridded hydrometeorological data sets, which are necessary for water‐related studies, particularly in some transboundary rivers that are partially without observation. Yet, GLDAS2.0 has only been validated at limited locations, and few studies have been conducted to develop approaches to correct the GLDAS2.0 data for transboundary rivers. This work assessed the GLDAS2.0 data and developed approaches to correct their uncertainties for studies in large transboundary rivers in the Tibetan Plateau and Northeast China (NC). To achieve these goals, observational data from 1982 to 2010 and a water and energy budget‐based distributed hydrological model including biosphere after calibration and validation were employed. We find that the GLDAS2.0 data (except for wind speed) can reasonably replicate observed seasonal variations. However, its specific humidity and wind speed have large uncertainty, and precipitation has large uncertainty in summer. In NC, the trends of its precipitation, air temperature, downward longwave radiation, and wind speed are consistent with the observations. In the Yarlung Tsangpo, Lancang, and Nu Rivers, the trends of all GLDAS2.0 data reproduce the observation very well, that is, wetting, warming, and dimming trends. Validations show that the corrections are effective and the corrected forcing data can be successfully used in hydrological simulation with improved performance than the raw GLDAS2.0 data, which demonstrates the usefulness of the methodology and corrected forcing data to hydrometeorological studies in transboundary rivers in China as well as in other nearby regions/countries. Plain Language Summary: GLDAS2.0 provides long‐term hydrometeorological data sets, which are necessary for water‐related studies, particularly in some transboundary rivers that are partially without observation. This work assessed GLDAS2.0 data and developed approaches to correct their uncertainties for studies in large transboundary rivers in the Tibetan Plateau (TP) and Northeast China (NC). In NC, the trends of GLDAS2.0 precipitation, air temperature, downward longwave radiation, and wind speed are consistent with observations. In TP, the trends of all the GLDAS2.0 data reproduce observation very well. Validations show that the corrections are effective and the corrected data have improved performance than raw GLDAS2.0 data in hydrological simulation. Key Points: Specific humidity and wind speed have large uncertainty, and precipitation has large uncertainty in summerTrends of precipitation, air temperature, downward longwave radiation, and wind speed are consistent with observationEquations are developed to reduce forcing data uncertainty, and validations show that the equations are effective [ABSTRACT FROM AUTHOR]

The chemical composition of the bottom sediments of the Amur River has been analyzed using modern analytical techniques. It was found that their composition and distribution patterns are controlled by several sources. The most probable sources for the bottom sediments of the studied area are siliceous magmatic or metasedimentary rocks. [ABSTRACT FROM AUTHOR]

A wide range of trace elements contained in solution and suspension in surface waters in Amur River basin, which are subject to different anthropogenic load, has been considered. They have been found to vary widely because of their natural conditions, the impact of anthropogenic factors near cities (Khabarovsk, Komsomol'sk-on-Amur), and transboundary transport from the territory of China. Dissolved Mo, Br, and I are proposed as tracers of such transport. [ABSTRACT FROM AUTHOR]

The article discusses the largely informal and multiple exchanges between Russia and China. It focuses on the activities and treatment of Chinese workers in agriculture and construction, trans-border logging operations of Chinese wood product companies as well as the unregistered Chinese entrepreneurs in Russia. It further relates the similarities and differences on the regional and urban economies of both countries particularly in the cities of Heihe and Blagoveshchensk. It also offers information on the economic condition of Russians in Heilongjiang Province in terms of employment and entrepreneurship.

This paper compares the distributions of dissolved and particulate forms of Mn, Fe, Ni, Cu, Zn, Cd, and Pb in the estuaries of the largest rivers in East Asia: the Amur River and the Changjiang (Yangtze River). High suspended solid concentrations, elevated pH, and relatively low dissolved trace metal concentrations are characteristics of the Changjiang. Elevated dissolved Fe and Mn concentrations, neutral pH, and relatively low suspended solid concentrations are characteristics of the Amur River. The transfer of dissolved Fe to suspended forms is typical in the Amur River estuary, though Cd and Mn tend to mobilize to solution, and Cu and Ni are diluted in the estuarine system. Metal concentrations in suspended matter in the Amur River estuary are controlled by the ratio of terrigenous riverine material, enriched in Al and Fe, and marine biogenic particles, enriched in Cu, Mn, Cd, and in some cases Ni. The increase in dissolved forms of Mn, Fe, Ni, Cu, Cd, and Pb compared with river end-member is unique to the Changjiang estuary. Particle-solution interactions are not reflected in bulk suspended-solid metal concentrations in the Changjiang estuary due to the dominance of particulate forms of these metals. Cd is an exception in the Changjiang estuary, where the increase in dissolved Cd is of comparable magnitude to the decrease in particulate Cd. Despite runoff in the Amur River being lower than that in the Changjiang, the fluxes of dissolved Mn, Zn and Fe in the Amur River exceed those in the Changjiang. Dissolved Ni, and Cd fluxes are near equal in both estuaries, but dissolved Cu is lower in the Amur River estuary. The hydrological and physico-chemical river characteristics are dominated at the assessment of river influence on the adjoining coastal sea areas despite differences in estuarine processes., (Copyright © 2014 Elsevier B.V. All rights reserved.)