Real-time PCR assay for detection and relative quantification of <Emphasis Type="Italic">Liocarcinus </Emphasis><Emphasis Type="Italic">depurator</Emphasis> larvae from plankton samples

Accurate species identification of decapod crustacean larvae is required to understand their population distributions, life cycle dynamics and interactions with their habitats. Analysis of plankton samples using morphological taxonomic methods and microscopy is time-consuming, requires highly skilled and trained operatives and may often be inaccurate. As complementary tools to classical identification methods, recent work has focused on the development of molecular approaches and shows their feasibility for species-specific identification. This study has developed real-time PCR assays utilising species-specific Taqman^® probes designed in the cytochrome oxidase I (COI) gene of Liocarcinus depurator, Necora puber, Carcinus maenas and Cancer pagurus. Our study then employed the probe and primers designed for L. depurator to obtain accurate identification and relative abundance estimates of L. depurator larvae in plankton samples collected between March 2005 and October 2006. Ranges of larval abundances were derived from a standard curve created from plankton samples spiked with a known number of larvae reared in the laboratory. Inhibition of the PCR reaction was shown to be an important factor and our results suggested that 0.1 ng of DNA as template provided accurate identification and avoided inhibition. Real-time PCR was shown to provide accurate species identification on unsorted plankton samples and could be suitable for the estimation of larval abundances in the plankton, although more work must be done to improve the accuracy of those estimations.     

上海郊区表层土壤中DDT残留特征

为掌握上海市北部郊区农田表层土壤有机氯农药残留状况,在上海市宝山区的农田分布区域布设采样点,采集表层土壤样品,用美国EPA方法分析了土壤中DDT及其4种衍生物的残留量.结果表明,上海市宝山区农田土壤中平均DDT总残留量为0.057 mg·kg-1,DDT的4种衍生物p,p'-DDE,p,p'-DDD,p,p'-DDT,o,p'-DDT的平均残留量分别为0.032、0.007、0.018、0.000 mg·kg-1.该研究中大部分区域土壤DDT总残留量低于国家土壤环境质量二级标准限值,没有形成土壤DDT污染;但在DDT残留量最高的地块,土壤DDT总残留量达0.694 mg·kg-1,超过了国家土壤环境质量二级标准限值,形成了一定范围的土壤DDT污染.在所有采样点中,有4个点位的p,p′-DDT/p,p′-DDE比值大于1,且其DDT总残留量也较高,说明这几块区域村在禁用期间又被新施加了DDT的可能.该研究可为有针对性地开展区域土壤环境保护和污染防治提供重要参考依据.     

城市绿地对小气候影响的研究进展

城市绿地对小气候的生态作用是研究城市绿地的重要问题.综述了国内外有关城市绿地对温度、湿度作用的研究报导,总结了城市绿地对温度、湿度影响的时空变化规律.目前城市绿地与温、湿度的关系多为定性研究,定量研究的技术与手段的局限使得定量研究还存在一定困难;城市绿地在美学、休憩等方面的潜在作用还无法定量研究;关于城市绿地群落结构与特性对小气候影响机制的研究还很少,这些都将是今后研究的重要方向.     

医疗废物无害化处置工艺设计

采取AB型热解两次焚烧(3T控制)和烟气净化处理新技术进行医疗废物无害化处置工艺设计,运行结果表明:该工艺技术能有效地处理医疗废物,具有无二次污染和社会、经济、环境效益好等优点,值得在实践中进一步推广应用。     

中国流通业CO2排放的因素分解和脱钩分析

参照IPCC清单中的方法估算了2000~2012年中国流通业CO2排放量;运用LMDI方法分解分析了研究期间流通业CO2排放变化的影响因素;并基于DPSIR框架构建流通业脱钩努力指数模型测度了流通业CO2排放脱钩效应.结果表明:2000~2012年间,流通业CO2排放量增长明显,期间累计排放总量为692482.37万t;产业规模效应是CO2排放增量的主要因素,能源强度效应是CO2排放减量的主要因素,分别引起CO2排放量增加了67435.72万t和减少了12358.67万t,能源结构和排放因子效应对CO2排放影响有限,分别引起CO2排放量增加了519.89万t和减少了2590.94万t;流通业CO2排放脱钩状态呈“弱脱钩—未脱钩—弱脱钩—未脱钩”的变化特征,脱钩努力指数值呈“ ”型变化趋势;目前能源强度是决定流通业CO2排放脱钩状态的关键因素,但随着能源强度的下降幅度越来越小,未来更需要通过调整能源结构和降低排放因子来实现流通业CO2排放脱钩.     

Biogeochemical transfer and dynamics of iodine in a soil–plant system

Radioactive iodide (¹²⁵I) is used as a tracer to investigate the fate and transport of iodine in soil under various leaching conditions as well as the dynamic transfer in a soil–plant (Chinese cabbage) system. Results show that both soils (the paddy soil and the sandy soil) exhibit strong retention capability, with the paddy soil being slightly stronger. Most iodine is retained by soils, especially in the top 10 cm, and the highest concentration occurs at the top most section of the soil columns. Leaching with 1–2 pore volume water does not change this pattern of vertical distributions. Early breakthrough and long tailing are two features observed in the leaching experiments. Because of the relatively low peak concentration, the early breakthrough is really not an environmental concern of contamination to groundwater. The long tailing implies that the retained iodine is undergoing slow but steady release and the soils can provide a low but stable level of mobile iodine after a short period. The enrichment factors of ¹²⁵I in different plant tissues are ranked as: root > stem > petiole > leaf, and the ¹²⁵I distribution in the young leaves is obviously higher than that in the old ones. The concentrations of ¹²⁵I in soil and Chinese cabbage can be simulated with a dual-chamber model very well. The biogeochemical behaviors of iodine in the soil-cabbage system show that cultivating iodized cabbage is an environmentally friendly and effective technique to eliminate iodine deficiency disorders (IDD). Planting vegetables such as cabbage on the ¹²⁹I-contaminated soil could be a good remediation technique worthy of consideration.     

原子吸收法测定土壤中铜锌铅镉

通过对几种消解体系的对比 ,选择出铅、镉最佳的消解方法为硝酸 氢氟酸 双氧水体系 ;铜锌最佳的消解方法为硝酸 氢氟酸 高氯酸体系。不同方法既能达到全量分析的要求 ,又能使基体干扰降到最小。通过对标准样品的多次测定 ,测定值均在其保证值范围内 ,铅镉相对标准偏差为 2 2 %～ 7 2 % ,加标回收率在 83%～ 116 %之间 ;铜锌相对标准偏差为 2 6 %～ 4 5 % ,加标回收率在 92 %～ 10 3%之间。     

城市富营养化河道复合酶-原位生物修复技术研究

研究了复合酶类生物激活物质对河道中微生物的作用机理,通过测定河道中微生物的生化呼吸线、细菌数、脱氢酶、纤维素酶、脲酶和磷酸酶的酶活性来表征生物激活物质对河道自净过程的促进作用。研究结果表明,复合酶污水净化剂对微生物活性具有激活作用,累积耗氧量明显增加,酶激活率达到14％～136％,有效增强了水体的自净能力。复合酶原位生物修复技术在上海、北京和福州等多条受严重污染的富营养化河道的工程应用表明,复合酶污水净化剂在不同的地域条件下均可发挥良好的作用,具有安全、高效和适用性广等特点。     

受污染景观水体的生物修复

应用生物刺激剂BIOE1对受污染的人工景观池水进行生物修复试验。现场试验的结果表明,生物刺激剂BIOE1能有效地对受污染的景观池水进行生物修复,处理后的池水清澈,水体中的溶解氧浓度显著提高,CODCr、氨氮、总磷和浊度的去除率分别为68%、93%、75%和83%。所用生物刺激剂不含外来微生物,对人体和鱼类无毒性。     

水相中CCl4和CHCl3的紫外光解机理

利用瞬态吸收光谱技术研究水体污染物CCl₄和CHCl₃在紫外光照条件下的转化和归宿,表明在248nm激光作用下,CCl₄解离为CCl₃和Cl自由基;CHCl₃在此条件下不解离,但加入少量的苯后即发生明显解离,产生CHCl₂和Cl自由基.在有氧条件下,光解产生的CCl₃和CHCl₂自由基均与O₂反应分别生成CCl₃O₂和CHCl₂O₂;在无氧条件下,CCl₃和CHCl₂则发生偶合反应分别生成C₂Cl₆和C₂H₂Cl₄.本研究还得出了一些微观速率常数.