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The risk assessment of water environments provides important references for water environment risk management. In this paper, the water environment risk of the upper rivers of the Baiyangdian Lake is assessed, considering both cumulative and sudden environmental risk. For the cumulative environmental risk assessment of the rivers, the characteristics of pollution transmissibility and accumulation in rivers was considered firstly. Furthermore, suggestions for the control of water environment pollution in the Baiyangdian Basin are given. The results indicate that the cumulative water environment risks of the Xiaoyi River—Dingzhou County, Xiaoyi River—Anguo County, Xiaoyi River—Boye County, and Xiaoyi River—Li County are high. The amount of fertilizer applied per unit of cultivated area, water quality, rate of water quality above the standard in water function zoning, and the ratio of environmental investment to gross domestic product (GDP) are important factors influencing the cumulative water environment risk. For sudden water environment assessments, the Xiaoyi River—Boye County is high. In the future, reducing the intensity of fertilizer application, strengthening the water quality control of the rivers, as well as upgrading the industry, should be carried out to protect the water environment in the Baiyangdian Basin. [ABSTRACT FROM AUTHOR]

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• We investigated the effects of windbreaks on PM emissions from agricultural soil erosion. • There is little impact of windbreak on PM 1 and PM 2.5 reduction. • PM 10 concentrations can be reduced significantly by windbreaks. • The settling velocity of particles has an impact on the effects of windbreaks. Wind erosion from agricultural fields contributes substantial amounts of particulate matter (PM) in the form of dust to the atmosphere, with significant impacts on air quality and human health. Vegetation barriers affect particle transport via altering air flow, yet the impact of windbreaks on PM concentrations from agricultural soil erosion is still unknown. This study describes brief campaigns to explore the effects of windbreaks on PM concentrations in Zhangbei County, Heibei Province, China. Measurements were made in arable lands with windbreaks, of which the dominant tree species was Populus , following dust events from April to May, when the trees were without leaves. We selected windbreaks with different structures and measured PM concentrations at the windward and the leeward sides of the windbreaks, using high time-resolution measurements. The effects of windbreaks were quantified by calculating the PM concentration ratios in front of and behind the windbreaks. During dust events, the average value of maximum PM 10 emissions was 109.87 μg/m3, which was above the threshold established by the World Health Organization (WHO) for air quality. The PM 10 emissions increased with air temperature and wind speed. The highest PM 10 emission was observed at a relative air humidity of 20%. PM 1 and PM 2.5 concentrations were not lower behind the windbreak than in front of the windbreak in most of the events, while PM 10 concentrations could be reduced by an average of 27%. A significant increase in PM 2.5 /PM 10 by 56.86% behind the windbreak indicates the high efficiency of the windbreak to reduce PM 10 levels. Simply planting trees can, in some cases, increase downwind PM concentrations. Vegetation configuration and avoiding locating residential areas in the immediate lee of windbreaks should be considered when planning windbreaks. [ABSTRACT FROM AUTHOR]

China has built four stations in Antarctica so far, and Zhongshan Station is the largest station among them. Continuous power supply for manned stations mainly relies on fuel. With the gradual increase in energy demand at the station and cost of fuel traffic from China to Zhongshan station in Antarctica, reducing fuel consumption and increasing green energy utilization are urgent problems. This research considers a standalone renewable energy system. The polar environments and renewable energy distribution of area of Zhongshan station are analyzed. The physical model, operation principle, and mathematical modeling of the proposed power system were designed. Low-temperature performance and state of charge (SOC) estimation method of the lead–acid battery were comprehensively tested and evaluated. A temperature control strategy was adopted to prevent the battery from low-temperature loss of the battery capacity. Energy management strategy of the power system was proposed by designing maximum power point tracking (MPPT) control strategies for wind turbine and PV array. The whole power system is broadly composed of a power generator (wind turbine and PV array), an uploading circuit, a three-phase rectifier bridge, an interleaved Buck circuit, a DC/DC conversion circuit, a switch circuit, a power supply circuit, an amplifier, a driver circuit, a voltage and current monitoring, a load, battery units and a control system. A case study in Antarctica was applied and can examine the technical feasibility of the proposed system. The results of the case study reveal that the scheme of standalone renewable energy system can satisfy the power demands of Zhongshan Station in normal operation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The appropriate parameters of the SaltMod model were calibrated and validated. • The appropriate water management strategies were proposed. • Irrigation and drainage measures played a significant role in controlling salinity. • Results indicate that the proposed model is useful for soil salinity modeling. Abstract Soil salinity is considered the most serious factor that limits food security and sustainable development of irrigated agriculture productivity, especially in arid and semi-arid regions. Irrigation and drainage management play a critical role in soil water dynamics, soil desalinization, and crop growth and yield. This study was conducted to determine the changes caused by salinization on cultivated lands and salt wastelands in the long term given the present irrigation and drainage practices and under the different water management scenarios. Moreover, this study was aimed at developing appropriate management strategies to decrease the salt accumulation based on long-term simulation results. A SaltMod model was calibrated and validated using data from 2010 to 2016. Leaching efficiencies of F lr = 0.85 and F lx = 0.65 in the root and transition zones and natural drainage of 0.10 m/year were determined, thereby providing the optimal match between the observed and simulated values. Prediction results showed that the salinity of the cultivated land would exhibit slight decrease in the next 10 years under the current irrigation and drainage conditions. The proposed irrigation schemes were analyzed to improve the soil desalination effect in the long-term. Results indicated that autumn irrigation water was increased by approximately 10%–20%, and summer irrigation water was decreased by approximately 15% in the prospective 10 years (2016–2026) based on the present irrigation conditions. Furthermore, the soil salinity will decrease by approximately 1.06%–10.92%, and the total irrigation water will decrease by approximately 50–295 m3/ha, thereby possibly contributing to improved water saving and soil desalination. [ABSTRACT FROM AUTHOR]

Seasonal freeze-thaw processes affect soil water migration and distribution, especially in semi-arid agricultural areas. These processes play an important role in mitigating harsh environmental conditions and wind erosion. Soil water content (SWC) and soil temperature (ST) were monitored at different depths (0–2 m) and investigated under freeze-thaw conditions from November 2018 to May 2019 in a semi-arid agro-pastoral region of northern China. The initial SWC was the main factor that affected the freeze-thaw process. During the freeze-thaw process, differences in soil thermal conductivity caused the soil to thaw faster than the freezing process, and the upper soil layer (0–60 cm) was significantly affected by temperature changes. Changes in the potential energy of water and pore pressure gradient caused the migration of soil water to the upper layer, which led to a slight decrease in SWC in each layer before ST dropped to the freezing point. The vertical migration distance of soil water exceeded 70 cm, and the SWC above a depth of 100 cm increased significantly, as water was mainly obtained from the soil layer below a depth of 200 cm. Soil compaction was reduced when affected by freeze-thaw processes and the soil particles were more fragmented, leading to wind erosion and dust events. Our results partially explain the occurrence of wind erosion in spring and provide a scientific basis for predicting soil water status and appropriate farmland management strategies. • Soil water content and soil temperature dynamic were quantified in farmland area. • Vertical migration distance of soil water exceeded 70 cm. • The initial SWC was the main factor that affected the freeze-thaw process. • Seasonal freeze-thaw processes will increase soil erodibility. [ABSTRACT FROM AUTHOR]

• Shelter forests mortality and its relationship with precipitation and soil water content was quantified. • Lower mortality of poplar (<32%) above 230 mm (precipitation) and an SWC > 16.56%. • A threshold response was evident when precipitation was 60% of normal. • Wind speed, low temperature, and stand density had effects on the mortality of shelter forests. Shelter forests in the agricultural field are critical ecological barriers against harsh environmental conditions and agricultural soil erosion in northern China; however, shelter forests have been extensively degraded in the past decades. It is unknown how patterns of mortality of shelter forests relate to highly variable spatial precipitation and soil water content (SWC). Here, we explore the relationships of precipitation and SWC with the mortality of Populus simonii Carr (poplar) shelter forests in the semi-arid Bashang Plateau, northern China. Mortality of poplar shelter forests and its relationship with precipitation and SWC are spatially quantified in an area with an uneven distribution of precipitation by combining standard field plot measurements, precipitation, and SWC spatial distribution grid data. The mortality patterns of poplar shelter forests revealed threshold responses to precipitation and SWC, with lower mortality (<32%) above 230 mm (precipitation) and an SWC > 16.56%. Results indicate that a threshold response is evident when precipitation is 60% of the average precipitation. In addition, our results show that wind speed, low temperature, and stand density also had significant effects on the mortality of poplar shelter forests. Our results show how precipitation and SWC patterns within a region influence the mortality of poplar shelter forests. Moreover, this study reveals other factors influencing stand structure and landscape heterogeneity, which have been largely overlooked in previous studies. [ABSTRACT FROM AUTHOR]

The transcription factor nuclear factor erythroid 2-like 2 (NFE2L2) is essential for preventing type 2 diabetes mellitus (T2DM)-induced complications in animal models. This case and control study assessed genetic variants of NFE2L2 for associations with T2DM and its complications in Han Chinese volunteers. T2DM patients with (n = 214) or without (n = 236) complications, or healthy controls (n = 359), were genotyped for six NFE2L2 single nucleotide polymorphisms (SNPs: rs2364723, rs13001694, rs10497511, rs1806649, rs1962142 and rs6726395) with TaqMan Pre-Designed SNP Genotyping and Sequence System. Serum levels of heme oxygenase-1 (HMOX1) were determined through enzyme-linked immunosorbent assay. Informative data were obtained for 341 cases and 266 controls. Between T2DM patients and controls, the genotypic and allelic frequencies and haplotypes of the SNPs were similar. However, there was a significant difference in genotypic and allelic frequencies of rs2364723, rs10497511, rs1962142 and rs6726395 between T2DM patients with and without complications, including peripheral neuropathy, nephropathy, retinopathy, foot ulcers and microangiopathy. Furthermore, HMOX1 levels were significantly higher in T2DM patients with complications than in controls. Multiple logistic regression analysis, however, showed that only rs2364723 significantly reduced levels of serum HMOX1 in T2DM patients for the GG genotype carriers compared with participants with CG+CC genotype. The data suggest that although NFE2L2 rs2364723, rs10497511, rs1962142 and rs6726395 were not associated with T2DM risk, they were significantly associated with complications of T2DM. In addition, only for rs2364723 higher serum HMOX1 levels were found in the T2DM patients with CG+CC than those with GG genotype., (© 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)