Speciation of Cu and Zn during composting of pig manure amended with rock phosphate

Pig manure usually contains a large amount of metals, especially Cu and Zn, which may limit its land application. Rock phosphate has been shown to be effective for immobilizing toxic metals in toxic metals contaminated soils. The aim of this study work was to investigate the effect of rock phosphate on the speciation of Cu and Zn during co-composting of pig manure with rice straw. The results showed that composting process and rock phosphate addition significantly affected the changes of metal species. During co-composting, the exchangeable and reducible fractions of Cu were transformed to organic and residue fractions, thus the bioavailable Cu fractions were decreased. The rock phosphate addition enhanced the metal transformation depending on the level of rock phosphate amendment. Zinc was found in the exchangeable and reducible fractions in the compost. The bioavailable Zn fraction changed a little during the composting process. The composting process converted the exchangeable Zn fraction into reducible fraction. Addition of an appropriate amount (5.0%) of rock phosphate could advance the conversion. Rock phosphate could reduce metal availability through adsorption and complexation of the metal ions on inorganic components. The increase in pH and organic matter degradation could be responsible for the reduction in exchangeable and bioavailable Cu fractions and exchangeable Zn fraction in rock phosphate amended compost.     

Enhanced removal of arsenic from a highly laden industrial effluent using a combined coprecipitation/nano-adsorption process

Effective arsenic removal from highly laden industrial wastewater is an important but challenging task. Here, a combined coprecipitation/nano-adsorption process, with ferric chloride and calcium chloride as coprecipitation agents and polymer-based nanocomposite as selective adsorbent, has been validated for arsenic removal from tungsten-smelting wastewater. On the basis of operating optimization, a binary FeCl₃ (520 mg/L)–CaCl₂ (300 mg/L) coprecipitation agent could remove more than 93 % arsenic from the wastewater. The resulting precipitate has proved environmental safety based on leaching toxicity test. Fixed-bed column packed with zirconium or ferric-oxide-loaded nanocomposite was employed for further elimination of arsenic in coprecipitated effluent, resulting in a significant decrease of arsenic (from 0.96 to less than 0.5 mg/L). The working capacity of zirconium-loaded nanocomposite was 220 bed volumes per run, much higher than that of ferric-loaded nanocomposite (40 bed volumes per run). The exhausted zirconium-loaded nanocomposite could be efficiently in situ regenerated with a binary NaOH–NaCl solution for reuse without any significant capacity loss. The results validated the combinational coprecipitation/nano-adsorption process to be a potential alternative for effective arsenic removal from highly laden industrial effluent.     

影响省级环境监测中心站职工积极性因素的调查

调查结果表明,在二十项调查内容中,省环境监测站职工普遍对工作条件类指标（单位的领导水平、良好的工作环境、和睦的人际关系、领导重视和单位的前途）寄予很高的期望。对经济类指标（福利待遇和稳定的经济收入）反映强烈。此外,对能够体现知识分子能力和水平的职称晋级问题也有较高的要求     

园艺生产中环境保护问题

园艺花卉产业的发展与其它农业生产一样，面临着各种环境问题，突出表现在化肥、农药对环境的污染、野生花卉种质资源和生产多样性的破坏以及对生物安全的威胁等。实现园艺花卉业可持续发展，应立足生态农业，提高科学技术水平和管理水平，保护野生花卉种质资源。同时，作者提出了野生花卉资源收集、保护、繁育等方面开发国际使用的设想。     

Chlorobenzenes and organochlorinated pesticides in vegetable soils from an industrial site, China

Organochlorinated compounds are ubiquitous contaminants in the environment, especially in industrial sites. The objective of the work was to investigate whether a vegetable field near an industrial site is safe for vegetable production. The residues of chlorobenzenes (CBs), hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in a vegetable field which was near a chemical plant in China were characterized. Point estimate quotient was used for ecological risk assessment of the investigated site. The results showed that all CBs except monochlorobenzene (MCB) were detected in soils. The total concentrations of ∑CBs ranged from 71.06 to 716.57 ng/g, with a mean concentration of 434.93 ng/g. The main components of CBs in soil samples were dichlorobenzenes (DCBs), trichlorobenzenes (TCBs) and tetrachlorobenzenes (TeCBs), while for single congeners, 1,2,4-TCB had the highest concentration, which ranged from 13.21 to 210.35 ng/g with a mean concentration of 111.89 ng/g. Residues of hexachlorobenzene (HCB) in soil samples ranged from 0.9 to 11.79 ng/g, significantly lower than ∑DCB, ∑TCB and ∑TeCB. Concentrations of ∑HCHs and ∑DDTs in soils ranged from 11.32 to 55.24 ng/g and from 195.63 to 465.58 ng/g, respectively, of which the main components were αup-HCH and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE). Ecological risk assessment for the investigated site showed that the most potential risks were from TCBs and TeCBs, based on the hazard quotients. The higher residues of CBs and DDTs compared to the target values and the higher than 1 hazard quotients indicated that this area is not safe for vegetable production and thus soil remediation is needed.     

建设项目环境影响评价中环境风险防范问题研究

结合建设项目环境影响评价报告书审查的实际,指出报告书中关于环境风险防范方面存在的编制依据的有效性、工程分析的完整性、环境风险评价的规范性、公众参与的针对性、社会稳定风险评估的真实性、环境监理的适用性和竣工环境保护验收的指导性等问题。根据国家近期对环境风险防范方面的法律法规等规定及研究成果,提出相应的改进建议。     

湖州地震台观测资料在汶川8.0级地震中的映震效应综合研究

在湖州地震台现有的形变、测震、流体三大学科的观测资料基础上,对汶川8.0级地震中的映震效应综合研究,得出了水管倾斜仪、伸缩仪,这两套仪器的NS、EW两个分项,在同一个观测环境中,仪器记录的同一个地震,精度高的分量,振幅不一定大;钻孔应变仪和伸缩仪、水位、水温仪安装不同的地点,两个观测点直线距离大约五公里,从记录资料上看,两者反映地下介质变化是一致的;地形观测资料的映震效应初始时间基本和p波到时同步,流体观测资料的映震效应初始时间基本和S波到时同步。     

磺胺类抗生素复合污染降解菌的筛选及其降毒作用

磺胺类抗生素是环境中检测出率较高的一类污染物.微生物降解是一种相对安全、高效且成本低的污染物去除技术,而关于磺胺类抗生素复合污染降解菌对该类抗生素的去除及其降毒能力方面的研究较少.因此,以3种磺胺类抗生素:磺胺吡啶(SP)、磺胺氯哒嗪(SCP)和磺胺二甲嘧啶(SM2)为碳源,从土壤中筛选3种磺胺类抗生素复合污染的降解菌...     

Heavy metal contamination of road-deposited sediments in a medium size city of China

The aim of this paper is to determine and compare the environmental factors controlling vertical colonisation of periphyton on Sparganium erectum in a shallow eutrophic turbid lake, Manyas Lake, and an oligo-mesotrophic deep lake, Sapanca Lake, Turkey during the July 1997--November 1998. To investigate the effect of the environmental factors on periphyton colonization on S. erectum, the stem was cut above the rhizomes and subdivided into three equal sections. Multivariate statistical analyses have been applied to clarify relationships between environmental variables and periphyton colonization on S. erectum. Results indicated that physical disturbance and trophic level of the lakes influenced the colonization of the periphyton. Among the measured parameters, low light intensity, total suspended solids, temperature and water level fluctuation were observed as driving factors in Manyas Lake whereas nutrient deficiency was found as key factor in Sapanca Lake. The zonation of the periphyton, density, composition and dominant/subdominant taxa were significantly different in these lakes. However, Oedogonium sp., Mougeotia sp., Cylindrocapsa sp., Cladophora glomerata (Linn.), Aulacoseira italica (Ehr.) Simonsen, Melosira varians C. Agardh, Navicula tripunctata (O.F. Müller) Bory and Fragilaria ulna (Nitzsch) Lange-Bertalot were found as dominant species at all sections of S. erectum both in Manyas Lake and Sapanca Lake. It can be thought that these species have a broad range of tolerance to several physical, chemical and hydrologic disturbances. This is the first study to introduce how much the water quality and hydrologic drivers have affected vertical colonization of periphyton on S. erectum in two lakes with different mixing regimes.     

氟化氢对水稻和青菜产量的影响

利用开顶式熏气装置,对水稻和青菜进行长时间的HF暴露试验。通过在熏气过程中对叶片电导率、含氟量和脯氨酸的分析比较,以及在熏气结束后对水稻穗数、千粒重和青菜鲜重的生物量统计测定,讨论和评价了HF对该作物产量的影响。