水中抗生素让人谈虎色变?

<正>央视新闻频道前不久曝光了鲁抗医药大量偷含排抗生素污水,浓度严重超标.一时间,关于饮用水安全问题,再次成为社会关注的焦点,引起公众对饮水健康的担忧.越来越多的微量抗生素在世界范围内的水环境中被发现,这些抗生素最终会通过饮用水和食物等渠道进入人体,对人类健康造成潜在威胁     

Relationships between soil and runoff phosphorus in small Alberta watersheds

Field-scale relationships between soil test phosphorus (STP) and flow-weighted mean concentrations (FWMCs) of dissolved reactive phosphorus (DRP) and total phosphorus (TP) in runoff are essential for modeling phosphorus losses, but are lacking. The objectives of this study were (i) to determine the relationships between soil phosphorus (STP and degree of phosphorus saturation (DPS)) and runoff phosphorus (TP and DRP) from field-sized catchments under spring snowmelt and summer rainfall conditions, and (ii) to determine whether a variety of depths and spatial representations of STP improved the prediction of phosphorus losses. Runoff was monitored from eight field-scale microwatersheds (2 to 248 ha) for 3 yr. Soil test phosphorus was determined for three layers (0 to 2.5 cm, 0 to 5 cm, and 0 to 15 cm) in spring and fall and the DPS was determined for the surface layer. Average STP (0 to 15 cm) ranged from 3 to 512 mg kg(-1), and DPS (0 to 2.5 cm) ranged from 5 to 91%. Seasonal FWMCs ranged from 0.01 to 7.4 mg L(-1) DRP and from 0.1 to 8.0 mg L(-1) TP. Strong linear relationships (r2=0.87 to 0.89) were found between the site mean STP and the FWMCs of DRP and TP. The relationships had similar extraction coefficients, intercepts, and predictive power among all three soil layers. Extraction coefficients (0.013 to 0.014) were similar to those reported for other Alberta studies, but were greater than those reported for rainfall simulation studies. The curvilinear DPS relationship showed similar predictive ability to STP. The field-scale STP relationships derived from natural conditions in this study should provide the basis for modeling phosphorus in Alberta.     

Wood carbon content of tree species in Eastern China: interspecific variability and the importance of the volatile fraction

Data on the mass density and carbon content of tree organs, and in particular stem wood, are essential for accurate assessments of forest carbon sequestration. However most available data, including that for East Asia, has neglected the volatile C fraction. Wood samples were collected and assayed for C content from 14 native tree species in Jilin Province, NE China. C content showed statistically significant variation among species, ranging from 48.4% to 51.0%. The volatile C fraction was non-negligible, averaging 2.2%, and showed high variation among species. As found in prior studies, wood C content was appreciably higher in conifer than hardwood (angiosperm) species (50.8+/-0.1% vs. 49.5+/-0.2%, respectively). Wood carbon density (gC/cm(3)) showed very high inter-specific variation, due mainly to differences in wood specific gravity. Our analyses, in conjunction with recently published data from North America, indicate a global mean value of 47.5+/-0.5% wood C content exclusive of volatile C; the widely used 50% figure corresponds more closely to total wood C inclusive of the volatile fraction. Failure to include volatile C or to use species- or higher-taxon-specific C content values in forest C assessments is likely to introduce biases on the order approximately 4-6%. In addition, the stocks and flows of the volatile C fraction in wood are in themselves an important and sorely neglected aspect of forest C processes likely to be strongly impacted by harvests and other management practices.     

环保领域四人获首届中国“杰出工程师奖”

10月16日,2014年度中国“杰出工程师奖”颁奖典礼在中央电视台隆重举行,由中国环境保护产业协会组织推荐的环保领域杰出工程师共有4人入选,其中廖志民同志获“杰出工程师奖”,张原、赵传军、范朝同志获“杰出工程师奖”鼓励奖。     

农村交通安全问题与对策

2021年9月份,我国一南一北接连发生两起农村交通安全事故,共造成27人死亡、3人受伤,分别是:9月4日,黑龙江勃利县一辆重型半挂车追尾一台拖拉机,致15人死亡1人受伤;9月5日,安徽省安庆市太湖县一辆运送除草农妇的皮卡车冲出道路,坠入深崖,事故造成12人死亡,2人受伤.这些事故再次暴露了我国农村交通安全存在的问题和短...     

除石油外：一种面向未来的生物质能源

如果有效的生物质能源系统以低的机会成本使用各种材料、仅需少量资金投入而且有建设弹性的话，它们就会抓住良好的商业成功的机会.这些能源系统的开发需要考虑更大的能源自主和总能源效率；农村和城市的发展趋势；在环境上更合理转化和使用技术的出现；以及实现最大可能碳回收的方法.对巴西发展乙醇燃料给予特别的关注.     

国家标准委征集2008年度公益性标准化科研项目

国家标准委征集2008年度公益性标准化科研项目 为促进搞好我国公益标准化工作,为国民经济和社会发展提供技术保障,国家标准委不久前以标委计函(2007)12号文发出通知,公开征集2008年重点在国家标准或国际标准层面的标准化公益性行业科研专项项目,要求其内容不得与国家科技计划及其他科技计划项目重复.申报项目必须坚持公益性、标准相关性、重点保障和自主创新原则.申报项目的重点领域是农产品、食品和消费品安全及检测方法,传统产业,高新技术和信息技术,服务领域,公共安全,资源节约和环境保护.在公共安全领域中,明确提出了要开展特种劳动防护用品及其安全材料标准的研究,充分反映出国家对PPE产业发展的重视.     

<中国环境科学>入网ChinaInfo(中国信息)网络资源系统<电子期刊>

为了实现科技期刊编辑、出版发行工作的电子化,推进科技信息交流的网络化进程,<中国环境科学>自1998年第1期入网"ChinaInfo(中国信息)网络资源系统<电子期刊>".凡在本刊发表的论文将由编辑部统一纳入ChinaInfo信息服务系统,进入因特网提供信息服务.