空气微生物不同高度分布情况研究

空气微生物是城市生态系统重要的生物组成部分,空气中广泛分布的细菌、真菌孢子、放线菌和病毒等生物粒子不仅具有极其重要的生态功能,还与城市空气污染,城市环境质量和人体健康密切相关。从生态系统角度出发,着重论述了城市微生物气溶胶的粒谱范围、空气微生物浓度和组成在不同高度变化的相关规律。     

Secondary organic aerosols in Jinan, an urban site in North China: Significant anthropogenic contributions to heavy pollution

Secondary organic aerosols(SOAs) are an important component of particulates, but whether biogenic SOAs(BSOAs) or anthropogenic SOAs(ASOAs) are the dominant contributors to haze pollution remains poorly characterized. In this study, particulate samples were collected from September 2014 to August 2015 at an urban site in Jinan, which is the capital of Shandong Province and a typical city in the North China Plain. The PM2.5 samples were analyzed for BSOA(isoprene(SOAI) and monoterpenes(SOAM)) and ASOA(aromatic(SOAA)) tracers. The concentrations of the SOAAtracer(1.1 ± 1.0 ng/m3) were lowest, and those of SOAItracers(41.8 ± 86.2 ng/m3) were highest, with the concentrations of SOAMtracers(19.4 ± 9.9 ng/m3) being intermediate. The SOAItracers were more abundant in the summer and less abundant in the winter. Both SOAIand SOAMincreased with increasing ozone level but decreased with increasing NOx level. Correlation analysis revealed a good correlation between 2,3-dihydroxy-4-oxopentanoic acid and levoglucosan levels in three seasons. These results suggested that biomass burning activities occurring in the NCP can enhance the emissions of aromatics and should be controlled, especially in the autumn and winter. SOA tracers were classified according to pollution degree, and the results showed that as pollution increases, the contributions of SOAAincrease. These results indicate that reducing anthropogenic emissions is necessary to prevent SOA pollution, especially during heavy pollution episodes.     

韶关市3座供水水库蓝藻种群及微囊藻毒素的季节变化

为了解供水水库的蓝藻种群和微囊藻毒素的季节变化,于2012年1—12月对韶关的苍村、瀑布和花山3座供水水库进行了采样分析。结果表明,3座水库为中营养型水库,监测蓝藻共9属(种),优势种为鱼腥藻和微囊藻,蓝藻最高丰度为5.67×107L-1;降水导致营养盐物质带入水库和水体不稳定性是蓝藻种群和优势种在夏秋两季季节变化和占优势的主要影响因子。3座水库ρ(微囊藻毒素)为0.1~0.9μg/L,最高值接近世界卫生组织对饮用水中MC-LR的指导性限制值(1μg/L)标准。微囊藻与微囊藻毒素呈显著正相关性(R=0.871,P0.01),表明产微囊藻毒素的蓝藻主要为微囊藻,当水库发生微囊藻水华时有发生微囊藻毒素的风险。     

卧龙湖浮游动物丰度的季节变化及其与水环境因子的关系

为给卧龙湖(国家良好湖泊生态环境保护试点)生态保护工作提供依据,文章于2014年5~10月对卧龙湖的浮游动物群落结构和不同水环境因子开展了监测,以期明确两者之间的关系。结果表明:研究区浮游动物丰度高,均值达到128.2×10~3 ind/L,浮游动物丰度季节差异显著(P<0.05),夏季(196.2×10~3 ind/L)>春季(154.0×10~3 ind/L)>秋季(25.1×10~3 ind/L);通过克里格插值分析,发现研究区浮游动物季节分布的空间异质性高,春季浮游动物丰度呈现从湖岸带到湖心递减趋势,南部是浮游动物的主要聚集区,而在夏秋季节,浮游动物丰度的高值区域逐渐向东北湖区偏移;通过典范对应分析,研究区内浮游动物分布主要受浊度、温度、营养物质和污染物等因素的影响,同时夏秋季节浮游动物丰度的高值区域逐渐向东北湖区偏移可能与城北明渠在湖区东北部汇入有关。     

Brood sex ratio adjustment in collared flycatchers (<Emphasis Type="Italic">Ficedula albicollis</Emphasis>): results differ between populations

Recently, a number of studies have found adaptive brood sex ratio (BSR) manipulation in birds. The reason for such manipulations is thought to be the different reproductive value of male and female nestlings. Several studies have found that parental quality and food supply can affect BSR, however results are sometimes inconsistent between species and populations. We investigated BSR patterns in a Hungarian population of Collared Flycatchers (Ficedula albicollis) and compared the results with those obtained in a previous study of the same species in Sweden. We found two significant differences. First, the male forehead patch size, a heritable, sexually selected trait, affected the brood sex ratio in the Swedish population, but not in our Hungarian study population. This difference might be a consequence of the different information content of the forehead patch size in the two populations. Second, a seasonal shift in BSR (more sons late in the season) was observed in the Hungarian, but not in the Swedish population.Communicated by J. Graves     

大气中甲磺酸粒子的来源及其对环境的影响

讨论了大气中甲磺酸粒子的来源,分析了甲磺酸粒子的自然循环及其对酸雨形成和气候变化的影响。     

山东省东平湖浮游动物与富营养化防治

根据1994年对东平湖6个采样点枯水期，丰水期，平水期浮游动物的调查，共获轮虫，枝角类，桡足类和原生动物66属100种，查明其数量和分布以及季节变化状况，确定了指示轻污带，β-中污带和α－－中污带的15个种及其分布，根据浮游统计结果。结果：其它方法，肯定了东平湖为中营养型一富营养型湖泊，按照综合防治富营养化原则，作者提出放养鲢鳙及搭配比较，以减少湖中着生藻类和浮游动物，防治富营养化，发展水产养殖业和旅游业，实现了可持续发展。     

Atmospheric deposition of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in urban and suburban areas of Korea

Bulk atmospheric samples (wet and dry) were collected monthly throughout a year at urban and suburban areas of Korea to assess the deposition flux and seasonal variations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). The PCDDs/DFs deposition fluxes ranged from 1.0 to 3.7 ng TEQ/m²/year in the urban area and from 0.5 to 4.6 ng TEQ/m²/year in the suburban area. The deposition fluxes of PCDDs/DFs in this study were comparable to or lower than those previously reported at different locations. The atmospheric deposition fluxes of particles and PCDDs/DFs in winter tended to be higher than those in summer. However, monthly variations between particle and PCDDs/DFs deposition fluxes were small, and the correlation coefficients between the deposition fluxes of air particles and each homologue group of PCDDs/DFs varied according to the degree of chlorination of the homologue group. The deposition velocity of PCDDs/DFs in the urban area was estimated at 0.04 cm/s, which is a lower value than those found in other studies. The two most likely factors affecting the monthly variation of deposition fluxes are the ambient temperature and the amount of precipitation. In particular, the ambient temperature had an influence on the lower chlorinated homologues of PCDDs/DFs while precipitation had an influence on the higher chlorinated PCDDs/DFs. The PCDDs/DFs profiles in atmospheric deposition bulk samples showed a similar pattern at the urban and suburban sites. The possibility of the loading of PCDDs/DFs by Asian dust events could be partly confirmed by investigation of homologue profiles.     

论灾害防治指导思想的转变

在与灾害进行斗争的长期过程中，人类逐步形成了关于灾害防治的指导思想，其中既有正确的、科学的成分．也有错误的、不合理的成分。本文依据灾害本身的性质与规律，从灾害与自然生态──社会经济系统的相互关系原理出发，分析并重新认识当代社会人类进行灾害防治工作的指导思想．以图确立正确的灾害防治指导思想．为减灾防灾工作顺利而有效的展开奠定基础。     

A study of the relationship between regional ferrous scrap prices in the USA, 1958–2004

This paper discusses univariate and mulitvariate methods used to deal with seasonal data with special emphasis on periodic models. These models are examined within the context of three regional U.S. ferrous scrap prices. All these variables can be described as being periodically integrated. The periodic models identified will be of use in assessing the future profitability of electric arc steel making. These scrap prices are shown to be periodically cointegrated in three of the four quarters with rapid speeds of adjustment to these long run equilibria. The cointegration relations have implications for the location of minimills.