试论原油罐区环境影响评价中的工程分析 ──以长庆石化分公司原油罐区建设项目为例

原油罐区环境影响评价中的工程分析必须深入、准确。文章总结了该类项目环境影响评价工作中工程分析的要点,并通过长庆石化分公司原油罐区工程实例加以实证说明,对该类项目环境影响评价工作有一定的指导作用。     

Factors affecting metal concentrations in the upper sediment layer of intertidal reedbeds along the river Scheldt

Factors that play a role in determining metal accumulation in sediments of 26 intertidal marshes which are mainly vegetated by reed plants (Phragmites australis) were assessed along the Scheldt estuary (Belgium and The Netherlands). In the upper 20 cm sediment layer, several physico-chemical properties (clay, silt and sand content, organic matter, carbonate and chloride content, pH and conductivity) and aqua regia extractable metals (Cd, Cr, Cu, Ni, Pb, Zn) were determined. The sediments were significantly contaminated with trace metals. The Cd concentrations often exceeded the Flemish soil remediation thresholds for nature areas, whereas Cr, Cu and Zn levels indicated moderate contamination. Pb concentrations occasionally were high, whereas Ni concentrations leaned towards background values. Organic matter was the single most important predictor variable for total metal contents in regression models, except for Cr. Additional significant predictor variables were clay or chloride content, depending on the metal. Observed metal concentrations at sites within a range of a few km from specific point-sources of metals (e.g. shipyards, industrial areas with metallurgic activities, affluents, major motorways) were somewhat higher than predicted by the models, whereas they were lower than predicted at sites which are regularly subjected to flooding by water of high salinity. The ratio between observed and predicted concentrations seems to be a valuable tool for the identification of areas which are specifically impacted by point sources.     

Influence of flooding and metal immobilising soil amendments on availability of metals for willows and earthworms in calcareous dredged sediment-derived soils

Soil amendments previously shown to be effective in reducing metal bioavailability and/or mobility in calcareous metal-polluted soils were tested on a calcareous dredged sediment-derived soil with 26 mg Cd/kg dry soil, 2200 mg Cr/kg dry soil, 220 mg Pb/kg dry soil, and 3000 mg Zn/kg dry soil. The amendments were 5% modified aluminosilicate (AS), 10% w/w lignin, 1% w/w diammonium phosphate (DAP, (NH₄)₂HPO₄), 1% w/w MnO, and 5% w/w CaSO₄. In an additional treatment, the contaminated soil was submerged. Endpoints were metal uptake in Salix cinerea and Lumbricus terrestris, and effect on oxidation-reduction potential (ORP) in submerged soils. Results illustrated that the selected soil amendments were not effective in reducing ecological risk to vegetation or soil inhabiting invertebrates, as metal uptake in willows and earthworms did not significantly decrease following their application. Flooding the polluted soil resulted in metal uptake in S. cinerea comparable with concentrations for an uncontaminated soil.     

不适宜生长条件对混茵降解苯胺的影响

分别从台州和衢州某化工厂的好氧池中分离筛选得到2株苯胺降解菌TZl和JH1,经16SrDNA测序鉴定为Comamonassp．TZ1和Pseudomonassp．JH1,均具有较强的苯胺降解能力,培养24h后,可使初始浓度为800mg／L的苯胺去除率达到96．4％～98．4％。在此基础上,按体积比l：1将2株菌液进行混合构建了混合菌体系,进而对比考察了苯胺初始浓度、pH、盐度和重金属等环境因子对单一菌和混合菌生长量及降解苯胺效果的影响,重点探讨混合菌对不适宜生长环境的适应性及其对苯胺的降解特性。通过单一菌和混合菌对比实验发现,在适宜苯胺初始浓度、pH和盐度条件下,混合菌的生长量略高于单一菌;在不适宜生长的高浓度苯胺、pH和盐度条件下,混合菌也表现出了更强的适应性和苯胺矿化能力。Zn2＋和Cr6＋耐受实验则表明,对于Cr6＋混合菌表现出了更强的耐受能力,而对于zn2＋并没有表现出更强的耐受能力。     

Combination of multispectral remote sensing, variable rate technology and environmental modeling for citrus pest management

The Lower Rio Grande Valley (LRGV) of south Texas is an agriculturally rich area supporting intensive production of vegetables, fruits, grain sorghum, and cotton. Modern agricultural practices involve the combined use of irrigation with the application of large amounts of agrochemicals to maximize crop yields. Intensive agricultural activities in past decades might have caused potential contamination of soil, surface water, and groundwater due to leaching of pesticides in the vadose zone. In an effort to promote precision farming in citrus production, this paper aims at developing an airborne multispectral technique for identifying tree health problems in a citrus grove that can be combined with variable rate technology (VRT) for required pesticide application and environmental modeling for assessment of pollution prevention. An unsupervised linear unmixing method was applied to classify the image for the grove and quantify the symptom severity for appropriate infection control. The PRZM-3 model was used to estimate environmental impacts that contribute to nonpoint source pollution with and without the use of multispectral remote sensing and VRT. Research findings using site-specific environmental assessment clearly indicate that combination of remote sensing and VRT may result in benefit to the environment by reducing the nonpoint source pollution by 92.15%. Overall, this study demonstrates the potential of precision farming for citrus production in the nexus of industrial ecology and agricultural sustainability.     

洞庭湖演变趋势分析

洞庭湖的演变制约湖区的资源开发与环境整治。根据洞庭湖的湖底淤积与湖泊水面缩小的速率，分别论述了目平涌，南洞庭湖和东洞庭湖的自然演变趋势。结合三峡工程对洞庭湖的影响。分析了建坝后洞庭湖泊水面的变化及河流入湖三角洲的发育。     

密云水库水质现状及发展趋势

１９９６－１９９７年对密云水库区水体和流域内水环境初步调查表明,库区水体的营养程度为中营养型;浮游藻类的群落结构为绿藻－硅藻型;湖泊的营养特征为浮游植物响应型,水质尚好,但水 ＴＮ,ＴＰ含量已分别达到１．２１ｍｇ·Ｌ＾－１和０．０２５ｍｇ·Ｌ＾－１,浮游藻类细胞密度已达到３４１７Ｃｅｌｌｓ·ｍｌ＾－１,水质有明显的向富营养化发展的趋势,对库区水体营养盐类的原因作了分析,并提出了保护水资源的措施。     

Occurrence of perfluoroalkyl substances in matched human serum, urine, hair and nail

The purpose of this study was to determine perfluoroalkyl substances(PFASs) in human serum, urine, hair and nail from general populations, and to investigate the possibility for human urine, hair and nail used as the biomonitoring sample for PFASs exposure. We detected the concentrations of PFHx A, PFOA, PFNA, PFDA, PFUn DA, PFDo A, PFHx S and PFOS in 39 matched human serum, urine, hair and nail samples from Shenzhen in China. The detection frequency and the median level of PFOS were all higher than that of the other PFASs in four matrices. The median concentration of PFOS in serum, urine, hair, and nail were 9.24 ng/mL, 13.96 ng/L, 0.58 ng/g and 0.63 ng/g, respectively. The results of spearman correlation test indicated that nail was an ideal matrix for biomonitoring PFOS rather than human urine and hair in general populations for the non-invasive sampling.     

中国经济持续发展水平的能值分析

在对现行可持续发展水平度量方法进行简要评述的基础上,提出了以能值分析(EMA)为理论支撑的区域性可持续发展评价指数。作为案例研究,计算了中国1978～1998年经济系统的可持续发展指数(ESI)。中国经济系统的ESI从高到低的变化历程表明,以经济系统能值流来衡量,中国经济发展的可持续性处于下降态势,表征为前期下降剧烈,目前趋于平缓。具体表现为对资源特别是能源的过度消耗以及对环境的持续强大压力。     

Optimized coagulation pretreatment alleviates ultrafiltration membrane fouling: The role of floc properties and slow-mixing speed on mechanisms of chitosan-assisted coagulation

To alleviate ultrafiltration(UF) membrane fouling, the pre-coagulation of poly-aluminum chloride(PACl) with the aid of chitosan(CTS) was conducted for synthetic humic acid–kaolin water treatment. Pre-coagulation of three molecular weights(MW) CTSs(50–190 kDa(CTSL), 190–310 kDa(CTSM) and 310–375 kDa(CTSH)) was optimized with slow-mixing speeds of 30, 60 and 90 r/min, respectively. The removal efficiency and floc properties as well as membrane fouling were analyzed, and were compared to results obtained by conventional coagulation with PACl. Results showed that variations in floc properties could be ascribed to the coagulation mechanisms of CTS_L/CTS_M/CTS_H at different slow-mixing speeds, resulting in reduced UF membrane fouling. Specifically, at the low speed of 30 r/min, all three CTS types produced flocs with similar properties, while CTSLresulted in the lowest removal efficiency and aggravated irreversible fouling. At the appropriate speed of 60 r/min, CTSMgenerated the most compact flocs with the combined effects of bridging and path mechanisms. The compact cake layer formed could alleviate irreversible fouling,which was beneficial for prolonging the operation of the UF membrane. At the high speed of90 r/min, CTSHformed fragile flocs and aggravated irreversible membrane fouling. We considered membrane fouling to be affected by floc properties and the resultant removal efficiency, which was governed by the MW of the CTS used and the slow-mixing speed applied as well.