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Qinghai Lake is the largest inland saltwater lake in China, with a drainage area of 29,661 km 2 . This study sought to conduct an ecological and human health risk assessment of metals and heavy metals, including copper, as well as investigate their concentration, distribution, and source distribution. In terms of seasonal variation, the increases in Fe, Cr, As, Pb, and Hg were relatively large, and the spatial distribution of metals presented a three-level stepped distribution trend, gradually increasing from east to west. By further exploring the source and migration path of pollutants, our study found that the source of metals in the sediments of Qinghai Lake is mainly controlled by five rivers entering the lake. Enrichment factor (EF) calculations indicated that the metal accumulation or enrichment capacity of the three central points in Qinghai Lake Basin was strong. Interestingly, the enrichment capacity of Cu and Zn was the strongest among all metals but occurred at low and medium concentration levels, respectively. The Igeo and [Formula: see text] ecological risk assessment results indicated that the individual metals posed little to no ecological risks to the Qinghai Lake Basin. However, the multi-element environmental risk comprehensive index (RI) indicated that Hg (RI = 147.97) represented a slight ecological hazard, Mn (RI = 181.13) posed moderate ecological hazards, and Zn (RI = 386.66) posed strong ecological hazards. The human health risk assessment results showed that the heavy metals in the surface sediments of Qinghai Lake currently do not pose a threat to human health. This information may facilitate the implementation of more stringent monitoring programs in the aquatic ecosystem by the relevant regulatory authorities., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Making clear of the background values of different watersheds is an important mission for water resource management and assessment. The background values of the virgin forested watershed with less human activities sometimes have high COD values. In order to investigate this issue, this study take the Tangwang River watershed as a study case, analyzing the monitoring data of COD, BOD, and DO from the year of 2014 to 2018, and taking the water samples in the wet, normal, and dry season of 2019 to make clear the relationships between COD and DOM, the composition, and source of DOM. The non-degradation and terrigenous source DOM contributed to the most of COD values through the fitting analysis. The DOM in the Tangwang River mostly consisted of the humic-like acid and fulvic-like acid. Along with the river, the concentration of DOM had a little decrease, but the composition of DOM did not change obviously, so that the DOM coming from the virgin forest did not degrade in the river, and the river water only had the dilution effect with the tributaries fed in spatially. The organic matters in the virgin forest were easily washed away, so that the DOM concentration had an increase in the wet season temporally. The background COD values of the small virgin forested watershed were usually high as for the leaching effects of the organic matters from the forest, which was worthy noted when conducting the management project of this kind of watershed, in order to adjust measures to local conditions., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A bibliometric method was used to evaluate the global scientific publications about sulfur oxides and nitric oxides released by coal-fired flue gas and vehicle exhaust from 1995 to 2018 and to provide insights into the characteristics of the articles and tendencies that may exist in the publications. Performance of publications, research tendency, and hotspots were analyzed. The article number had an explosive growth in 2004 and, then, began to grow steadily. China had an absolutely advantage in publication quantities; however, America had a leading position considering publication cited times. The simultaneous removal of mercury, particulate matter, and CO 2 was a research hotpot in sulfur oxide and nitric oxide control process; oxidation, absorption, and catalytic reduction were the central control methods that had the most strength in relation with sulfur dioxide and nitric oxide. Considering the study of traditional flue gas pollutant control method (limestone-gypsum method, selective catalytic reduction, etc.) was perfection, it was speculated that adsorption by ionic liquid, electricity charging, advanced oxidation progress, and multi-pollutant removal, simultaneously, would be the new research orientation in flue gas pollutant control. One of the hot points of controlling the vehicle exhaust was the application of the "green energy" biodiesel; lots of keywords concerning human health suggested that quite a lot studies were focused on the health hazard brought by sulfur oxides and nitric oxide.

Electric power system involves different fields and disciplines which addressed the economic system, energy system, and environment system. Inner uncertainty of this compound system would be an inevitable problem. Therefore, an inexact multistage fuzzy-stochastic programming (IMFSP) was developed for regional electric power system management constrained by environmental quality. A model which concluded interval-parameter programming, multistage stochastic programming, and fuzzy probability distribution was built to reflect the uncertain information and dynamic variation in the case study, and the scenarios under different credibility degrees were considered. For all scenarios under consideration, corrective actions were allowed to be taken dynamically in accordance with the pre-regulated policies and the uncertainties in reality. The results suggest that the methodology is applicable to handle the uncertainty of regional electric power management systems and help the decision makers to establish an effective development plan.