覆盖作物及耕作方法对土壤丝状真菌生物量的影响

以日本国立大学法人茨城大学农学部田间科学教育研究中心附属农场为研究对象,在不同季节(2004年5月、10月和2005年5月、10月)对农田采取旋耕、梨耕和免耕处理,并在每一耕作处理区分别种植黑麦(Secale cereale L .)、毛野豌豆(Vicia villosa Roth)和杂草(休闲处理对照区),来研究覆盖作物及耕作方法对土壤中真菌生物量的影响效果.结果表明,在免耕处理区,覆盖黑麦、毛野豌豆和杂草的土壤表层(0～10 cm)中,其真菌的牛物量均分别高于相应覆盖物的深层土壤(10～30 cm)中真菌的生物量,并且覆盖黑麦的土壤表层中真菌的生物量比覆盖毛野豌豆的高很多,在2004年5月和10月测得的土壤表层中,覆盖黑麦的真菌生物量分别是覆盖毛野豌豆的1.2和1.8倍,在2005年5月和10月,分别是1.6和1.2倍.对旋耕和梨耕处理区,在不同深度的土层和覆盖物的条件下,真菌生物量均没有明显变化.从上述结果,不同的耕作方式和覆盖不同的作物都会影响土壤中真菌的生物量,并且,免耕和覆盖黑麦相结合,对土壤表层中的真菌生物量影响最为显著.另外,在不同的土壤层之间,表层中的真菌生物量要高于深层土壤.     

等离子体烟气脱硫脱硝工业试验装置

介绍等离子体烟气脱硫脱硝技术原理及发展现状,等离子体烟气脱硫硝工业试验装置的工艺流程、技术参数及了调节系统、加速器辐照处理系统、脉冲电晕放电处理系统等。     

A rapid method for screening of the Stockholm Convention POPs in small amounts of human plasma using SPE and HRGC/HRMS

A rapid analytical screening method allowing simultaneous analysis of 23 persistent organic pollutants (POPs) in human plasma was developed. Sample preparation based on solid-phase extraction (SPE) with additional clean-up using small multilayer silica gel columns. SPE was performed using a custom made polystyrene-divinylbenzene sorbent for the extraction of chlorinated and brominated POPs. Special efforts to reduce sample volume and improve speed and efficiency of the analytical procedure were made. Determination of 16 polychlorinated biphenyls (PCBs), 5 organochlorine (OC) pesticides, octachlorinated dibenzo-p-dioxin (OCDD) and polybrominated diphenyl ether (BDE #47) in 0.5 mL human plasma was performed by using high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). Recovery of POPs ranged between 46% and 110%, and reproducibility was below 25% relative standard deviation (RSD) for all target compounds, except for trans-nonachlor and OCDD, which were present only at low levels. Limits of detection (LOD) were for the PCBs between 0.8 and 117.7 pg mL⁻¹ plasma and for the OC pesticides between 5.9 and 89.1 pg mL⁻¹ plasma. The LOD for OCDD and BDE #47 were 1.4 pg mL⁻¹ plasma, and 9.2 pg mL⁻¹ plasma, respectively. The presented method was successfully applied to 1016 human plasma samples from an epidemiological study on cardiovascular disease.     

阴阳树脂比例对电去离子处理镍废水的影响

采用一级两段的混床EDI膜堆,模拟了Ni2+电镀废水为处理对象,考察了膜反应器在树脂比例的膜堆废水出水水质的影响。实验结果表明,在处理原水进水流量为20L/h、含Ni2+约52mg/L的NiSO4溶液时,随着阴/阳树脂比例的增加,膜堆废水内部水解离加剧,发生沉淀现象,废水出水pH值增高;当阴/阳树脂比例为2:3时处理效果最佳,废水中Ni2+离子的浓度降至0.6mg/L,去除率达到97.9%,不发生结垢现象。     

一项福及子孙荫及后代的工程——“水专项”

5月,因太湖蓝藻再次暴发,饮用水安全再次告急,环境保护部再次组织专家遣往太湖等重点流域考察、把脉。其实蓝藻事件历来已久,随着气温高升和污染加重,近两年蓝藻暴发程度、面积都超于往年,各重大水域危矣!国家16个科技重大专项之一“水专项”专治水问题,是一项福及子孙荫及后代的工程,因为水是生命之源,文明之根。     

周生贤在全国环境监测工作会议上指出 加强建设先进环境监测预警体系为推进环保历史性转变提供保障

2月28日-29日,国家环保总局在京召开全国环境监测工作会议.环保总局局长周生贤出席会议并讲话.他说,加强环境监测,是加快推进历史性转变的重要保障,是实现"十一五"污染减排目标的必然要求,是提升环境管理能力的迫切需要,是深化国际环境合作的有效手段.要进一步明确新时期环境监测工作的目标和任务,加快建设先进的环境监测预警体系,全力推进环境保护历史性转变.     

Black carbon-dominated PCDD/Fs sorption to soils at a former wood impregnation site

The influence of black carbon (BC) on the sorption of 17 native polychlorinated-p-dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was studied in five soil samples from a sawmill site where wood used to be impregnated with chlorophenol preservatives. The presence of BC caused measured total organic carbon (TOC)-water distribution ratios (K(TOC)) to be a median factor of 51 (interquartile range 18-68, n=85) higher than modeled amorphous organic carbon (AOC)-water distribution ratios (K(AOC)). K(TOC) was a factor of 73+/-27 above K(AOC) for PCDFs (n=10) and a factor of 20+/-13 (n=7) for PCDDs. The reason for this difference is probably that attaining a planar configuration after sorption to BC is less thermodynamically favorable for PCDDs than for PCDFs. BC-water distribution ratios were calculated from K(TOC), K(AOC) and BC contents, and ranged from 10(9.9) (2,3,7,8-Tetra-CDD) to 10(11.5) l kg(-1) (Octa-CDF). More than 90% of the PCDD/Fs in the soil was calculated to be BC-sorbed. Dissolved organic carbon (DOC)-water distribution ratios were measured to be in the same order of magnitude as K(AOC). This study shows that strong sorption to BC should be included when assessing ecotoxicological risk or modeling transport to groundwater of PCDD/Fs in soil.