黄海和东海海域溶解氧的分布特征

根据黄河和东海海区四个季度的调查资料，描述了溶解氧的时空分布和变化规律。黄、东海溶解氧分布的基本特征是北高南低，西高东低，随着水温的变化，不同季节这一差别有所不同。黄、东海溶解氧平均值分别为495．4和420．3μmol/L，测定范围分别为90．2－681．9和133－9－692．8μmol/L。以长江口以东H断面为例，描述了夏季溶解氧的断面分布特征，在20－30m水层出现一氧跃层，30m以下垂直分布比较均匀。文中还深入研究了东海陆架区黑潮水溶解氧的分布特征和变化规律。     

辽东湾海冰漂移的动力要素分析

利用辽东海JZ20－2海域冰期气象、水文和海冰的实测资料和海冰数值模拟结果，对海冰漂移过程中风和流的拖曳力、海冰内力、科氏力和海面倾斜力要素的基本特征进行了分析；采用海冰热力－动力模式对1999年2月3日6：50至2月5日6：50间辽东湾海冰进行了48h数值模拟，对并JZ20-2海域的海冰动力要素进行了对比分析。发现海冰内力、风和流的拖曳力为同一量级，海面倾斜力和科氏力明显较小，其均值的比例关系依次为14．7：18．8：32．6：1．5：1．0；海冰各动力要素相互影响，共同决定了海冰的漂移速度和运动轨迹。     

固定化细胞技术在废水处理中的应用

固定化细胞处理废水是近年发展起来的废水处理新技术,其优点是:①能在生物处理装置内维持高浓度的生物量,提高处理负荷,减少处理装置容积;②污泥产量低,固定化活性污泥的剩余污泥产量仅为普通活性污泥法的1/4—1/5;③可选择性地固定优势菌种,提高难降解有机物的降解效率;④抗有毒物毒性能力强,在废水处理中显示出极大潜力。本文主要介绍国内外有关固定化细胞技术及其在废水处理中的应用研究和发展前景。     

安徽铜陵地面塌陷现象初析

铜陵市区内,近来发生了大面积地陷与地裂,造成严重灾害,引起了各界广泛的关注。本文着重探讨这种灾害的发生原因及其防灾对策。     

活性炭吸附烟气脱硫技术的工业性试验

宜宾发电总厂进行了活性炭吸附烟气脱硫技术 10× 10 4 m3 /h烟气量工业性试验。试验结果表明 ,该技术脱硫率达 70 %以上 ,运行简便 ,适用性广 ,副产品可综合利用 ,具有显著的经济效益和较好的应用前景     

可持续发展视角下的城镇化与都市化抉择——基于国际生态足迹面板数据实证研究

在人口众多、人均资源匮乏、生态环境脆弱的中国,都市化与中小城镇化何种城市化模式更符合可持续发展的要求,存在争议。通过对中国、美国、加拿大、英国、法国、日本、意大利、澳大利亚、韩国、巴西、印度、墨西哥、南非等发达国家与主要发展中国家的生态足迹、生态承载力、城镇人口比重等宏观面板数据的计量分析,揭示城市化客观规律,并与中国实际结合。研究表明:其一,百万以上人口城市的都市化更符合生态资源的可持续性。其显著降低人均生态足迹与生态环境压力,并倾向于增加人均生态承载力。如此促进生态资源的供给,削减生态资源的人均需求而有利于可持续发展。其二,百万以下人口城市的中小城镇化显著增加生态足迹与生态环境压力。其布局结构松散,倾向于占用大量生态环境资源,减少生态承载力供给;而低效、分散、粗放的生产生活方式也增加生态足迹,总体不利可持续发展。其三,人均固定资本存量、人均储蓄、政府购买都对可持续发展具有潜在的促进作用。最后,建议中国推行都市化战略,充分发挥大都市的规模经济效应,提高生态环境资源的利用效率;适度限制城镇化,避免中小城镇遍地开花对资源环境造成显著危害;学习国际优秀城市化经验及相关配套制度,并与中国结合;注重技术创新,发挥高新科技及资本带来的生产方式改进与效率提升。     

Effects of fenvalerate concentrations and its chiral isomers on bacterial community structure in the sediment environment of aquaculture ponds

To investigate the effect of chiral pesticide fenvalerate (FV) on the micro-ecological environment of aquaculture pond sediment, we used an indoor static experiment to observe the effects of FV added at different concentrations with different chiral isomers on the changes in the sediment bacterial community. The 16S rDNA high-throughput sequencing technique was used to conduct sequencing and analysis of the bacterial community structure as well as changes in aquaculture pond sediments after 4 weeks of cultivation. The results showed that the microbial alpha diversity indices (Sobs and Shannon indices) of the treated groups were significantly lower than those of the control group after 4 weeks (P < 0.05), and the values in the high-concentration group were significantly lower than those of the low-concentration group (P < 0.05). In terms of bacterial group composition, the proportion of abundance of Proteobacteria and Acidobacteria in the treated groups were greater than in the control group after 4 weeks, while the proportion of abundance of Bacteroidetes and Verrucomicrobia were lower. In the high-concentration FV treatment group, the proportion of abundance of Bacteroidetes, Acidobacteria, Chloroflexi, Nitrospinae, unclassified_k_norank, Ignavibacteriae, and Nitrospirae were significantly different from those of the other groups (P < 0.05). Principal coordinate analysis (PCoA) and ANONISIM/Adonis analysis showed that the cis-enantiomer had a stronger effect on the bacterial community as the concentration of FV increased. In addition, the linear discriminant analysis effect size (LEfSe) and linear discriminant analysis (LDA) results revealed differences in the level of enrichment of bacterial groups caused by FV at different concentrations and isomer levels. Collectively, this study showed that FV residue has a pronounced effect on bacterial communities in sediment, which becomes more significant with increasing exposure concentration. The effects of the cis- and trans-enantiomers of FV on the sediment environment are different; the cis-enantiomer has a stronger effect on the bacterial community.

     

Antibiotic accumulation,growth performance,intestinal diversification,and function of Nile tilapia (Oreochromis niloticus) feed by diets supplemented with different doses of sulfamethoxazole

Environmental Science and Pollution Research - To comprehensively investigate the effects of exposure to legal doses of sulfamethoxazole (SMZ) in Nile tilapia (Oreochromis niloticus), fishes were...