Sustainable Management of Electronic Waste (e-Waste)

Electronic waste or e-waste is one of the fastest growing areas of the international waste stream and is increasing at a much higher rate than all other waste streams. Fast growing electronics industries arising from the demands of information and communication technologies around the world coupled with the rapid product obsolescence and lack of end-of-life management options, have all led to the unsustainable management of the waste stream. Computers are manufactured from over 1,000 materials, many of which are toxic, and they contribute significantly to the e-waste stream, which is estimated to be ca. 20 to 50 million tonnes annually. Design for environment cleaner production, extended producer responsibility, standards and labeling, product stewardship, recycling and remanufacturing are some of the practices adopted by various countries around the world to deal with the e-waste stream. An overview of these practices is presented and the manner in which they contribute to the sustainable management of e-waste is discussed.     

Barometric pumping effects on soil gas studies for geological and environmental characterization

Data from two free soil gas sampling programs are evaluated for the effects of barometric pumping over time on measured soil gas volumes. One program collected data from the trapped atmosphere immediately above two hazardous waste landfill areas. Of these areas, one had extremely high soil gas emanations, whereas the other had a more modest soil gas release. The second experimental program involved the collection of free soil gas samples on a rough grid with an approximate spacing of 1.6 km over a 720-sq-km area. This reconnaissance effort was designed to establish regional soil gas background values and to establish the utility of this method as a geological mapping tool in the Atlantic Coastal Plain. Methane, ethane, propane, and hydrogen data are used for this study. The data suggest that there is a predictable change in soil gas volume with a given change in barometric pressure. The rate of change is greater with large soil gas volumes in permeable soils versus lower soil gas volumes in impermeable soils; however, a simple linear relationship seems to generate a predictable curve with a margin of error of approximately 50%. Furthermore, the results of this study indicate that barometric pumping effects should be strongly considered during soil gas screening efforts at hazardous waste sites as well as in regional studies for hydrocarbon source potential mapping.     

Relationship of photosynthetic carbon fixation with environmental changes in the Jiulong River estuary of the South China Sea, with special reference to the effects of solar UV radiation

Phytoplankton cells in estuary waters usually experience drastic changes in chemical and physical environments due to mixing of fresh and seawaters. In order to see their photosynthetic performance in such dynamic waters, we measured the photosynthetic carbon fixation by natural phytoplankton assemblages in the Jiulong River estuary of the South China Sea during April 24-26 and July 24-26 of 2008, and investigated its relationship with environmental changes in the presence or the absence of UV radiation. Phytoplankton biomass (Chl a) decreased sharply from the river-mouth to seawards (17.3-2.1 μg L⁻¹), with the dominant species changed from chlorophytes to diatoms. The photosynthetic rate based on Chl a at noon time under PAR-alone increased from 1.9 μg C (μg Chl a)⁻¹ L⁻¹ in low salinity zone (SSS < 10) to 12.4 μg C (μg Chl a)⁻¹ L⁻¹ in turbidity front (SSS within 10-20), and then decreased to 2.1 μg C (μg Chl a)⁻¹ L⁻¹ in mixohaline zone (SSS > 20); accordingly, the carbon fixation per volume of seawater increased from 12.8 to 149 μg C L⁻¹ h⁻¹, and decreased to 14.3 μg C L⁻¹ h⁻¹. Solar UVR caused the inhibition of carbon fixation in surface water of all the investigated zones, by 39% in turbidity area and 7-10% in freshwater or mixohaline zones. In the turbidity zone, higher availability of CO₂ could have enhanced the photosynthetic performance; while osmotic stress might be responsible for the higher sensitivity of phytoplankton assemblages to solar UV radiation.     

Spatial analysis of anthropogenic impact on karst geomorphology (Slovenia)

The objective of this contribution is analyzing, visualizing, interpreting and discussing the impacts of anthropogenic influences on karst geomorphology through various geomorphologically based environmental indicators. The primary data sources are digital terrain models (DTMs) as continuous surface data, supported by aerial photographs, satellite images, topographic maps and databases of natural and anthropogenic features. The sources are supplemented by written information about surface changes and in situ inspections. Spatial analyses as quantitative methods in combination with enhanced visualizations as qualitative methods performed in a geographical information system (GIS) on different data sets are introduced as an important methodology. This enables explaining many anthropogenic influences on the terrain surface (landform), which were not perceived before by classical surveying techniques and verifications.     

环境水力学研究中的预报模型的研究现状

主要介绍目前世界上环境水力学研究中,湍流模式下,预报模型的发展、现状及种类。并简单分析了模型的原理以及模型的适用性与非适用性,来说明实际工程中对瑞流模式研究的重要性和可行性。     

华北地区人类文化遗址的地球化学环境演变

在地球演化历史上,第四纪是人类诞生、发展和壮大的时代,它所形成的地质产物中记录了丰富的生态环境信息。河北省境内第四纪岩石地层(泥河湾组、赤城组、马兰组、迁安组)的风化指数CIA,Fe2O3/FeO,Fe/Mn等地球化学参数可作为年均气温、年均降雨量等气候因子的近似代用指标;华北地区人类文化遗址所在地水系沉积物中Hg,Sn和Au等元素含量随人类文明的演进而阶段性增高。这一结果表明,人类为了适应不断变化的自然地理环境(寒冷、干旱),不得不进行技术创新,从而产生了农业耕作、工业革命及现代信息产业等文明进步成果,但与此同时,却也导致了地质环境的人为污染,甚至可能引发全球温室效应。     

哈拉湖岩芯XRF扫描元素统计分析及其环境意义

青藏高原东北缘高山湖泊哈拉湖是位于季风与西风影响的交汇带的封闭深水湖泊,是区域环境和气候变化的良好记录载体。目前对该湖的研究还较少,缺乏对沉积物中元素环境意义的系统认识。通过高分辨率XRF岩芯扫描,用相关、聚类和因子分析的方法对哈拉湖沉积岩芯地球化学元素进行分析。结果显示Ti、K、Si、Al、Fe、Mn等元素变化一致,相关性高,归为同一类,即径流输入的陆源碎屑组分,反映了流域水文状况如径流量的变化。Sr、Zr元素相关性高,为赋存在粗颗粒沉积物中的元素,根据哈拉湖实际,应为冬季湖泊冰面风力搬运,反映了湖区冬季风力强度的变化。Ca元素既与径流输入元素总体变化一致,也与Sr、Zr元素显著相关,且在第一和第二主成分(径流和风力)上的载荷相当,表明哈拉湖沉积物中的碳酸盐既有粗颗粒的外源碎屑,也有湖泊自生的组分,这在利用碳酸盐进行地球化学研究时应重视,注意去除外源碎屑碳酸盐的影响。可溶元素S和Cl可能反映了入湖水量与蒸发对比情况,与湖泊盐度有关。     

Exploitation or 'Wise Use' of the Coongie Lakes,South Australia: Issues arising from a petroleum exploration proposal

The exploitation of natural resources within areas that are valued for their environmental qualities raises competing emotions. This paper considers a proposal to undertake petroleum exploration in an area of recognised environmental value, namely, the Coongie Lakes of far north-east South Australia. In development cases such as this, the level of inquiry needs to address environmental, social, cultural and economic issues from a range of interest groups; therefore, the process of assessment is a crucial factor in minimising conflict and meeting the wishes of the stakeholders. In the example of Coongie Lakes, the chosen method failed. This paper discusses the perspectives of the major stakeholders, the process of assessment undertaken, and the criticisms directed at this process. The apparent inadequacies of the assessment process undertaken are then highlighted, and an alternative assessment procedure suggested.     

我国砷中毒病区的环境特征研究

我国饮水型砷中毒的流行屡见报道,台湾嘉南,新疆奎屯,内蒙古河套及山西大同等地是我国几个有代表性的病区。病区多为河湖相和滨海相沉积,粘土,粘土质淤泥和有机淤泥层发育,为富含有要质的还原环境,地下水中的含量一般为０．２－０．６ｍｇ／Ｌ。有时还有氟,腐殖酸,甲基胂酸和某些烷烃类等的有害有机化合物。