鲮（Cirrhinus molitorell）入侵长江水系的可能性探讨

鲮（Cirrhinus molitorella〗）是分布于我国华南地区的一种热带、亚热带鱼类，历史上未曾分布于长江水系。鲮食性广、性成熟时间短，繁殖量大，但不耐低温。2010年10月，对长江宜昌江段鱼类资源调查中发现了一种非长江水系土著种的野鲮亚科鱼类。基于鳞片、鳍条、口器、腮耙等特征鉴定为鲮（C. molitorella）。进一步结合鲮的生物学特征和长江水温及水生态环境状况对鲮的进入途径和成为入侵鱼类的可能性进行了初步的探讨，并对其成为入侵鱼类的危害和防治进行了初步讨论。     

Ce-PbO_2/C电极的制备及其去除水中酸性红B

采用电沉积法制备铈修饰的PbO2/C电极,通过SEM、XRD、XPS及循环伏安对PbO2/C、Ce-PbO2/C电极进行表征,结果表明,Ce-PbO2/C电极比PbO2/C颗粒细小,表面均匀致密,电化学氧化能力较强,修饰电极中Ce以CeO2的形态存在。以Ce-PbO2/C为工作电极,电解浓度为1 000 mg/L的高盐酸性红B模拟活性染料废水,考察了电压、pH、电解质浓度、极间距对脱色率、氨氮去除率及COD去除率的影响。确定适宜工艺条件为：初始酸性红B溶液浓度为1 000 mg/L,pH值为6,电压10 V,电解时间1 h,电极间距1.5 cm,该条件下脱色率、氨氮去除率和COD去除率分别为99.98%、97.23%和90.17%。通过UV-Vis及GC-MS初步分析了降解过程可能存在的中间产物及降解途径。     

脂肽类生物表面活性剂液体发酵条件的响应面优化

通过Plackett-Burman和Box-Behnken实验对解淀粉芽孢杆菌XZ-173液体发酵生产表面活性素进行了响应面优化研究。首先使用Plackett-Burman实验对影响表面活性素产量的17个因素进行显著性筛选,结果表明,MnSO4、CuSO4、温度和转速为显著性因素。再运用Box-Behnken实验对这4个显著因素的取值进一步优化,得到各因素优化后的数值分别为4.4 mg/L(MnSO4)、0.18 mg/L(CuSO4)、29℃(温度)和163 r/min(转速)。响应面分析结果表明:该菌株产生表面活性素的最佳培养基为:葡萄糖15 g/L,蛋白胨5 g/L,L-谷氨酸钠6 g/L,KH2PO40.8 g/L,MgSO40.4 g/L,KCl 0.4 g/L,酵母提取物3 g/L,L-苯丙氨酸2.5 mg/L,MnSO44.4 mg/L,CuSO40.18 mg/L,FeSO40.12 mg/L;最适培养条件:pH 7.5,温度29℃,转速163 r/min,接种量5%,装液量50 mL/250 mL,摇床培养36 h。在优化后的条件下,表面活性素实际产量为336 mg/L,实际实验结果与模型预测结果相一致。表面活性素采用HPLC技术分离,发现其在浓度仅为50 mg/L时EI24就可达到70%以上,反映了表面活性素优异的乳化活性以及广阔的应用前景。     

Preliminary Strategic Environmental Assessment of the Great Western Development Strategy: Safeguarding Ecological Security for a New Western China

The Great Western Development Strategy (GWDS) is a long term national campaign aimed at boosting development of the western area of China and narrowing the economic gap between the western and the eastern parts of China. The Strategic Environmental Assessment (SEA) procedure was employed to assess the environmental challenges brought about by the western development plans. These plans include five key developmental domains (KDDs): water resource exploitation and use, land utilization, energy generation, tourism development, and ecological restoration and conservation. A combination of methods involving matrix assessment, incorporation of expert judgment and trend analysis was employed to analyze and predict the environmental impacts upon eight selected environmental indicators: water resource availability, soil erosion, soil salinization, forest destruction, land desertification, biological diversity, water quality and air quality. Based on the overall results of the assessment, countermeasures for environmental challenges that emerged were raised as key recommendations to ensure ecological security during the implementation of the GWDS. This paper is intended to introduce a consensus-based process for evaluating the complex, long term pressures on the ecological security of large areas, such as western China, that focuses on the use of combined methods applied at the strategic level.     

苏州国际旅游节城市旅游效应研究与思考

现代节庆活动发展迅速,有效塑造了城市旅游形象,促进了城市旅游业的发展。以苏州国际旅游节为例,对历届苏州国际旅游节进行了初步梳理和分析,利用相关数据,对其产生的旅游经济效应、社会文化效应和环境效应进行了综合评价,认为苏州国际旅游节成功塑造了苏州的城市形象,刺激了苏州旅游业发展,有利于苏州旅游资源的有效整合。当前苏州国际旅游节在运营模式、主题创新和当地居民参与度等方面还存在一些问题,对此进行了思考并提出改进建议,以期更好地发挥苏州国际旅游节的整体旅游效应。     

Phytoavailability and geospeciation of cadmium in contaminated soil remediated by Rhodobacter sphaeroides

A microorganism was isolated from oil field injection water and identified as Rhodobacter sphaeroides. It was used for the remediation of simulated cadmium-contaminated soil. The phytoavailability of Cd was investigated through wheat seedling method to determine the efficiency of remediation. It was found that after remediation, the accumulation of Cd in wheat roots and leaves decreased by 67% and 53%, respectively. The Cd speciation in soil was determined with Tessier extraction procedure. It was found that the total Cd content in soil did not change during the experiments, but the geo-speciation of Cd changed remarkably. Among the five fractions, the concentration of exchangeable phases decreased by 27-46% and that of the phases bound to Fe-Mn oxides increased by 22-44%. The decrease of Cd accumulation in wheat showed significant positive correlation with the decrease of exchangeable phases. It could be concluded that the remediation of R. sphaeroides was carried out through the conversion of Cd to more stable forms. The decrease of sulfate concentration in supernatant indicated that the R. sphaeroides consumed sulfate.     

Migration of natural estrogens around a concentrated dairy-feeding operation

Concentrated animal feeding operations have been recognized as one of the most important contributors of natural estrogens which show significant endocrine-disrupting properties in aquatic environments. In this study, the concentrations of 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), estrone (E1), and estriol (E3) in several matrices, including soils (surface and deep), sediments (surface and deep), and groundwaters, around a typical dairy farm were surveyed using gas chromatography/mass spectrometry. Of the two farmlands, surface and subsurface sediments in waste lagoon and along effluent drainage drench, the concentrations of 17α-E2, 17β-E2, and E1 ranged from below detection limit to the highest level of 6.60 μg/kg, except that E3 was not detectable. Three estrogens of 17α-E2, 17β-E2, and E1 with the concentrations of 3.18-31.61 ng/L were observed in two groundwater samples. The results clearly demonstrated the vertical migration and horizontal transport of estrogens in the investigated area. Within 750-m distance, it was observed the attenuation of 17α-E2, 17β-E2, and E1 along the effluent route and the horizontal migration of estrogens was less than 1,350 m in this survey.     

给水曝气生物滤池内置粉末活性炭复合净水效果的研究

在给水曝气生物滤池内置粉末活性炭,对比分析其对各工艺单元水质净化效果的影响,确定给水曝气生物滤池内置粉末活性炭的作用与最佳投加量,研究表明,给水曝气生物滤池将活性炭截留在滤池内,大幅度提高了粉末活性炭利用率,部分未饱和粉末活性炭通过反冲洗排入后续常规处理系统,作为生物载体仍能够进一步发挥生物强化作用。当粉末活性炭的投加量为8 mg/L时,砂滤出水氨氮、CODMn、浊度和色度均值分别为：0.02 mg/L,1.82 mg/L0,.46 NTU和6度,去除率分别达到99.6%、71.2%、99.1%和80.6%,出水指标达到《生活饮用水卫生标准（》GB5749-2006）和《饮用净水水质标准（》CJ94-2005）规定的标准。与常规工艺相比,投加量降低了20%～60%。     

河道沉积物中磷的分布、吸附及释放规律研究

为科学评价磷在河道沉积物中的环境行为,在模拟条件下研究了上海市进木港和苏州河沉积物中磷的分布形态、吸附特征及释放规律.结果表明:(1)2种沉积物中碎屑钙磷(De-P)浓度最高,闭蓄态磷(Oc-P)次之,其他形态磷浓度相对较低,而活性磷中以铁磷(Fe-P)为主；(2)2种沉积物对磷的吸附均符合线性方程,在4.0h时基本达...     

Identification of cadmium-excluding welsh onion (Allium fistulosum L.) cultivars and their mechanisms of low cadmium accumulation

Purpose

Screening out cadmium (Cd) excluding cultivars of a crop in agricultural production is an effective way to prohibit Cd entering into food chain.

Methods

A judging criterion for Cd-excluding cultivars based on food safety was suggested and used in the identification of Cd-excluding welsh onion (Allium fistulosum L.) cultivars. A pot culture experiment was carried out to screen out Cd-excluding cultivars, of which the results were confirmed by plot experiments. The relevant factors of Cd accumulation in the pseudostem were analyzed and used in the correlation analysis aiming to study the low Cd accumulation mechanisms.

Results

The concentration of Cd in the pseudostem of welsh onions was 0.08?C0.20, 0.18?C0.41, and 0.26?C0.61?mg/kg fresh weight (FW) under three treatments (1.0, 2.5, and 5.0?mg/kg), respectively. The significant (p? ₃ ^? ?CN, and eight other elements in the tested welsh onion cultivars. Two cultivars were identified as Cd-excluding cultivars, mainly because the accumulation of Cd in their pseudostem was only 0.041?±?0.003 and 0.046?±?0.002?mg/kg FW, and 0.054?±?0.001 and 0.066?±?0.011?mg/kg FW, when growing in plots with Cd concentration of 0.49 and 0.99?mg/kg, respectively.

Conclusions

Ribentiegancongwang and Wuyeqi could be identified as Cd-excluding cultivars. Low bioaccumulation factor of the roots was the main mechanism of Cd-excluding welsh onion cultivars.