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981.
982.
983.
Jiang JG 《Environmental pollution (Barking, Essex : 1987)》2006,139(2):306-317
We developed a new biotic index of species pollution value (SPV) and community pollution value (CPV) based on the correlation of protozoan communities with chemical water quality to assess freshwater pollution. Five hundred and twenty-three species of protozoa SPV were established based on the data of River Hangjiang and Lake Donghu. The present research was conducted in order to further consummate the biotic index. Protozoa of the water system in Changde City were collected from 16 stations using the PFU method and the water chemical parameters of the stations were analyzed. The results showed that CPV calculated from SPV had a close correlation with the degree of water pollution (p < 0.00001), which indicated that the method is reliable. By combining the data of River Hangjiang, Lake Donghu and Changde City, the final form of SPV was accomplished and the SPV list increased to 757. The ultimate water standard evaluated by CPV calculated from SPV was proposed. 相似文献
984.
Metal contamination in sediments of the western Bohai Bay and adjacent estuaries, China 总被引:5,自引:0,他引:5
Feng H Jiang H Gao W Weinstein MP Zhang Q Zhang W Yu L Yuan D Tao J 《Journal of environmental management》2011,92(4):1185-1197
Twelve sediment cores were collected in July 2007 in open waters of western Bohai Bay, the Port of Tianjin, and the adjacent estuaries of the Haihe and Yongding Rivers. While overall concentrations of trace metals at incremental depths in these cores met the Marine Sediment Quality (GB18668-2002) criteria of China, the magnitude of both metal enrichment factors (EF) and geoaccumulation indices (I(geo)) suggested that pollution with Ag, Cd, Cr, Cu and Zn was occurring in the estuaries and Port. Risk analysis also suggested that Ag and Ni concentrations were sufficiently elevated as to cause adverse biological effects in the study area. Although metal concentrations in western Bohai Bay were of less concern, a positive relationship between EF values and excess (210)Pb activity for several metals suggested that their concentrations were increasing over time. 相似文献
985.
为了探索水体中Cr(Ⅵ)对脊尾白虾(Exopalaemon carinicauda)的毒性效应,通过Cr(Ⅵ)的暴露(15 d)和清水恢复实验(15d),研究了Cr(Ⅵ)对脊尾白虾肝胰脏的SOD活性、MDA及MTs含量的影响.结果表明,通过15 d的暴露,5 mg·L-1(高浓度)、0.5 mg· L-1(低浓度)实验组肝胰脏的SOD均显著高于对照组水平(p<0.05),15 d的清水恢复后,两个浓度实验组均能够恢复到对照组水平(p>0.05).MDA在暴露阶段呈现持续上升的趋势,且在15 d后两个浓度实验组MDA的含量均显著高于对照组水平(p<0.05),15 d的清水恢复后,5mg·L-1实验组的MDA含量依然显著高于对照组水平(p<0.05),0.5mg·L-1实验组的MDA含量基本恢复到对照组水平(p>0.05).通过15 d的暴露,两个浓度实验组MTs的含量均显著高于对照组水平(p<0.05),15 d的清水恢复后,两个浓度实验组MTs的含量均能够恢复到对照组水平(p>0.05). 相似文献
986.
Chaojie Jiang Lifen Liu John C. Crittenden 《Frontiers of Environmental Science & Engineering》2016,10(4):15
In this study, a new water treatment system that couples (photo-) electrochemical catalysis (PEC or EC) in a microbial fuel cell (MFC) was configured using a stainless-steel (SS) cathode coated with Fe0/TiO2. We examined the destruction of methylene blue (MB) and tetracycline. Fe0/TiO2 was prepared using a chemical reduction-deposition method and coated onto an SS wire mesh (500 mesh) using a sol technique. The anode generates electricity using microbes (bio-anode). Connected via wire and ohmic resistance, the system requires a short reaction time and operates at a low cost by effectively removing 94% MB (initial concentration 20 mg?L–1) and 83% TOC/TOC0 under visible light illumination (50 W; 1.99 mW?cm–2 for 120 min, MFC-PEC). The removal was similar even without light irradiation (MFC-EC). The E Eo of the MFC-PEC system was approximately 0.675 kWh?m–3?order–1, whereas that of the MFC-EC system was zero. The system was able to remove 70% COD in tetracycline solution (initial tetracycline concentration 100 mg?L–1) after 120 min of visible light illumination; without light, the removal was 15% lower. The destruction of MB and tetracycline in both traditional photocatalysis and photoelectrocatalysis systems was notably low. The electron spinresonance spectroscopy (ESR) study demonstrated that ?OH was formed under visible light, and ?O 2 – was formed without light. The bio-electricity-activated O2 and ROS (reactive oxidizing species) generation by Fe0/TiO2 effectively degraded the pollutants. This cathodic degradation improved the electricity generation by accepting and consuming more electrons from the bio-anode.
相似文献
987.
988.
Temporal-spatial variability and fractal characteristics of soil nitrogen and phosphorus in Xinji District, Hebei Province, China 总被引:1,自引:0,他引:1
Rutai Gao Shuqing Liu Yigong Zhang Huizhuo Li Yuanfang Huang Xunfeng Xia Tiantian Jiang Hui Zhang 《Environmental monitoring and assessment》2011,174(1-4):229-240
Traditional statistics, geostatistics, fractal dimensions, and geographic information systems (GIS) were employed to study the temporal?Cspatial variability of soil total nitrogen (TN) and total phosphorus (TP) levels in Xinji District, Hebei Province area of the North China Plain from 1980 to 2007. The results indicate that nutrient levels follow normal or lognormal distributions. The TN content was 0.59 ±0.155 g kg???1 in 2007, an increase of 0.44 g kg???1 compared with that of 1980. In 2007, the TP content was 1.21 ±0.227 g kg???1, an increase of 0.01 g kg???1 from 1980. The geostatistical analysis showed that the distribution of these soil nutrients in the study area exhibits a trend and anisotropy. The range and [C 0/(C 0?+?C)] of TN and TP in 1980 were all less than in 2007. The ordinary kriging interpolation method was used to analyze the nutrient contents differences between 1980 and 2007. The results indicate that soil TN levels have increased over the 27-year period, and the area where the TN level had increased by at least 0.4 g kg???1 was about 61.7% of the district. The area where the TP content increased covered about 58.4% of the district. The variance analysis indicated that land-use type had a clear influence on the distribution and change in TN and TP content. Using the 3-D box-counting dimension method combined with GIS, the fractal dimension of soil nutrient spatial distribution over the two periods showed that in 27 years, the fractal dimension of TN increased from 1.95 to 2.02, and the fractal dimension of TP increased from 1.89 to 2.01, indicating that the complexity of the spatial distribution of all nutrient contents had increased. This study can provide a basis for accurate fertilizing and to enhance the conversion of soil characteristics under different spatial scales. 相似文献
989.
Shengliu Yuan Xiaoman Jiang Xinghui Xia Haixia Zhang Shaokui Zheng 《Chemosphere》2013,90(10):2520-2525
The liquid chromatography–electrospray ionization-tandem mass spectrometer (LC–MS/MS) method coupled with an automated solid-phase extraction procedure has been developed to identify 22 psychiatric pharmaceuticals, including seven anxiolytic-sedative-hypnotics, six antidepressants, and nine anti-schizophrenia drugs, in wastewater samples from two psychiatric hospital wastewater treatment plants (P-WWTPs) and three municipal wastewater treatment plants (M-WWTPs) in Beijing, China. Analyte recoveries from spiking experiments in the WWTP influent and effluent at three concentrations ranged from 70% to 110%, excluding sulpiride, ziprasidone, and olanzapine. Method detection limits for five, eight, and nine analytes in the WWTP influent and effluent were 20–80, 1–16, and <1 ng L?1, respectively. High psychiatric pharmaceutical concentrations (e.g., ~942 ng L?1oxazepam, 5552–12,782 ng L?1 clozapine, 2762–9832 ng L?1sulpiride, and 2030–4967 ng L?1quetiapine) were frequently observed in P-WWTP influent compared to M-WWTPs. Although P-WWTPs typically had higher removal rates, significantly higher concentrations of the target compounds were observed in the P-WWTP secondary effluent than in the M-WWTP influent (e.g., ~752 ng L?1oxazepam, ~8183 ng L?1 clozapine, ~10,833 ng L?1sulpiride, and ~1168 ng L?1quetiapine). Thus, the discharge control of psychiatric pharmaceuticals from psychiatric hospitals requires improvement. 相似文献
990.
Cong Zhong Zhongfang Yang Wei Jiang Tao Yu Qingye Hou Desheng Li Jianwu Wang 《Environmental science and pollution research international》2014,21(21):12305-12315
Industrialization and urbanization have led to a great deterioration of air quality and provoked some serious environmental concerns. One hundred and five samples of atmospheric deposition were analyzed for their concentrations of 13 trace elements (As, Cd, Cu, Fe, Al, Co, Cr, Hg, Mn, Mo, Pb, Se, and Zn) in Shanxi Basin, which includes six isolate basins. The input fluxes of the trace elements in atmospheric deposition were observed and evaluated. Geostatistical analysis (EF, PCA, and CA ) were conducted to determine the spatial distribution, possible sources, and enrichment degrees of trace elements in atmospheric deposition. Fe/Al and K/Al also contribute to identify the sources of atmospheric deposition. The distribution of trace elements in atmospheric deposition was proved to be geographically restricted. The results show that As, Cd, Pb, Zn, and Se mainly come from coal combustion. Fe, Cu, Mn, Hg, and Co originate mainly from interactions between local polluted soils and blowing dust from other places, while the main source of Al, Cr, and Mo are the soil parent materials without pollution. This work provides baseline information to develop policies to control and reduce trace elements, especially toxic elements, from atmospheric deposition. Some exploratory analytical methods applied in this work are also worth considering in similar researches. 相似文献