Distribution and ecotoxicological significance of trace element contamination in a ~150 yr record of sediments in Lake Chaohu, Eastern China

This paper presents the concentrations, vertical profiles and possible sources of selected major and trace elements in a sediment core covering ～150 years of sedimentation in Lake Chaohu, eastern China. Element concentrations were measured by portable X-ray Fluorescence Spectroscopy (XRF) and were used to evaluate possible environmental consequences of the recent industrialization in China. Statistical analyses identify four groups: (1) organic carbon (OC), total nitrogen (TN), Pb, Zn, and As associated with the use of chemical fertilizers and pesticides; (2) Mn, Cr, Ni and Cu from industrial and mining activities; (3) Fe, Rb, K, Co, Ti and Ca influenced by post-depositional processes and land exploitation; and (4) Zr and Sr from the soil. The vertical profiles of elements placed in the first two groups show distinct increases in concentrations above depths of 20 cm (~1978), coincident with the timing of industrialization in China, and the anthropogenic-derived fluxes are higher than the lithogenic-derived fluxes over the last three decades. With the exception of Zr and Sr, association of the measured metals with organic carbon and nitrogen suggests that organic matter may act as a carrier phase. The geoaccumulation index (I(geo)) reveals increased contamination from elements in the first two groups in recent years. Element concentrations, compared with the Effects Range-Low (ERL) and Effects Range-Median (ERM) levels set by NOAA, suggest that adverse biological effects from Ni contamination are very likely.     

Surfactant-assisted adsorption of uranyl ions in aqueous solution on TiO2/polythiophene nanocomposite

In this work, hexadecyltrimethylammonium-bromide (HTAB)-modified polythiophene (PTh)/TiO₂ nanocomposite (HTAB/PTh/TiO₂) was applied to remove uranyl ions (UO₂²⁺). FT-IR, XRD, ζ potential, TGA, SEM, and XPS were utilized to obtain the chemical and physical properties of HTAB/PTh/TiO₂. The effects of HTAB content, preparation temperature, and adsorption conditions on UO₂²⁺ removal were investigated comprehensively. And the UO₂²⁺ adsorption process on HTAB/PTh/TiO₂ was fitted to the Sips model with a saturated adsorption capacity of 234.74 mg/g, which was 6 times over TiO₂. The results suggested that the surfactant of HTAB can significantly improve the adsorption ability of TiO₂ for UO₂²⁺ ions. This work provides a strategy of surfactant modification for enhancing the separation and recovery ability of adsorbent toward UO₂²⁺ in the radioactive wastewater.

     

Life cycle and economic assessment of enhanced ecological floating beds applied water purification

Environmental Science and Pollution Research - The ecological floating beds (EFB) are widely used in water quality restoration because of its low cost, high efficiency, and green characteristics....     

Antibiotic and antiparasitic residues in surface water of urban rivers in the Red River Delta (Hanoi,Vietnam): concentrations,profiles, source estimation,and risk assessment

Environmental Science and Pollution Research - Antibiotic residues and antimicrobial resistance in surface water are issues of global concern, especially in developing countries. In this study, the...     

The relationship between maternal perfluoroalkylated substances exposure and low birth weight of offspring: a systematic review and meta-analysis

Environmental Science and Pollution Research - Some studies have shown that maternal perfluoroalkylated substances (PFAS) exposure may be associated with low birth weight (LBW) of offspring. We...     

Correlation between PM concentrations and aerosol optical depth in eastern China

Using one year of Aerosol Optical Depth (AOD) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite and particular matter (PM) contents measured at eleven sites located mostly in the eastern China in 2007, the relationship between columnar AOD and hourly and daily average (DA) PM were established. The peak AOD observed from MODIS was generally consistent with the surface PM measurements in eastern China, where Zhengzhou had the maximum annual mean PM₁₀ of 182.1 μg m^?3, while Longfengshan had the minimum annual mean of 38.1 μg m^?3. Ground level observations indicated that PM concentration varies widely across different regions, which was mainly due to the difference in weather conditions and anthropogenic emissions. The coarse particles accounted for the main air pollution in Zhengzhou and Benxi whiles the fine particles, however, were the main constituents in other sites. Results showed that MODIS AOD (averaged over the box of 5 × 5 and 3 × 3 pixels) had a better positive correlation with the coincident hourly average (HA) PM concentration than with DA due to diurnal variation in PM mass measurements. After correcting AOD for relative humidity (RH), the correlation did not improve significantly, suggesting that the RH was not the main factor affecting the correlation of PM with AOD. The statistical regression analysis between MODIS AOD and PM mass suggested that the satellite-derived AOD is a useful tool for mapping PM distribution over large spatial domains.     

滤速对慢滤池深度处理生活污水的影响

为进一步提高再生水水质,将慢滤池用于污水二级处理出水的进一步处理。选取浊度、COD、色度和细菌总数4个指标,利用实验室小试装置,研究了0.1、0.3、0.5m/h这3种滤速下慢滤池的性能。结果表明,滤速由0.1m/h升高至0.3m/h时,慢滤池出水水质略有下降。而滤速由0.3m/h升高至0.5m/h时,慢滤池出水水质下降显著。滤速小于等于0.3m/h时,慢滤出水浊度、COD、色度和细菌总数平均为0.4NTU、25.9mg/L、14.9°、5×10^3CFU/mL。慢滤对这4个指标的平均去除率分别为78.6%、36.0%、34.0%、62.3%。为获得优良的水质,建议慢滤池用于污水深度处理时,滤速宜小于0.3m/h。但实际工程中,用户对再生水水质要求不高时,则可适当增大慢滤池滤速。     

Phosphorus Losses to Water from Lowland Rice Fields under Rice–Wheat Double Cropping System in the Tai Lake Region

To assess P losses to surface water by runoff during the rice season and by drainage flow during the winter wheat season, serial field trials were conducted in different types of paddy soils in the Tai Lake Region (TLR) during 2000 and 2001. Four P application rates were set as 0 (CK), 30, 150, and 300 kg P/hm² for flooded rice trials and 0 (CK), 20, 80, 160 kg P/hm² for winter wheat trials respectively. Field experiments were done in two locations with a plot size of 30 m² and four replications in a randomized complete block design. A simplified lysimeter was installed for each plot to collect all the runoff or drainage flow from each event. Total P (TP) losses to surface water during rice season by runoff flow from four treatments were 150 (CK), 220 (T30), 395 (T150), 670 (T300) g P/hm² in year 2000, and 298, 440, 1828, 3744 g P/hm² in year 2001 respectively in Wuxi station, here the soil is permeable paddy soil derived from loam clay deposit. While the losses were 102, 140, 210, 270 in year 2000, and 128, 165, 359, 589 g P/hm² in year 2001 respectively in Changshu station, here the soil is waterlogged paddy soil derived from silt loam deposit. During the winter wheat season, total P lost from the fields by drainage flow in the four treatments were 253 (CK), 382 (T20), 580 (T89), 818 (T160) g P/hm² in year 2000–2001, and 573.3, 709.4, 1123.2, 1552.4 g P/hm² in year 2001–2002 at the Wuxi station. While these were 395.6, 539.1, 1356.8, 1972.1 g P/hm² in year 2000–2001, and 811.5, 1184.6, 3001.2, 5333.1 g P/hm² in year 2001–2002 at the Changshu station. Results revealed that P fertilizer application rates significantly affected the TP concentrations and TP loads in runoff during the rice season, and by drainage flow during the winter wheat season. Both TP loads were significantly increased as the P application rate increases. The data indicate that TP losses to surface water were much higher during the winter wheat season than during the rice season in two tested sites. The data also reveal that the annual precipitation and evaporation rate affected the soil P losses to surface water significantly. Year 2000 was relatively dried with higher evaporation thus P losses to water by both runoff and drainage flow were less than in year 2001 which was a relatively wet year with lower evaporation. Results indicate that texture, structure of the soil profile, and field construction (with or without ridge and deep drains) affected soil P losses to surface water dramatically. Annual possible TP lost to water at the application rate of 50 kg P/hm² year tested in TLR were estimated from 97 to 185 tones P from permeable paddy soils and 109–218 tones P from waterlogged paddy soils. There was no significant difference of TP lost between the CK and the T50 treatments in both stations, which indicate that there is no more TP lost in field of normal P fertilizer application rate than in control field of no P fertilized. Much higher TP lost in runoff or drainage flow from those other P application rates treatments than from the T50 treatment, which suggest that P losses to surface water would be greatly increasing in the time when higher available P accumulation in plough layer soil in this region.     

水口山有色金属公司实施互保联保的经验

针对矿山安全生产现状，3年来在矿山职工中实施安全生产互保联保管理，有效地促进了矿山安全生产，并取得了良好的效果。     

污染因子相关分析判定地下水污染源

把相关分析用于地下水污染源的判定,在安阳市劳教所一带地下水污染事故中成功地判定了污染源