城市老工业区整体搬迁规划环评的关键问题

城市老工业区搬迁规划环评具有层次多、涉及面广的特点。评价首先要分清规划的层次,理清3个层面规划内容,分析所涉及到的主要环境问题,按照规划、区域和项目环评3个层次分别开展评价工作。在规划层面上应重点解决好产业发展政策的符合性和选址合理性论证;区域环评层面重点进行区域布局、结构、基础设施的支撑能力和环境的承载力评价;项目层次重点弄清污染特征、污染源和污染控制措施,评价其环境影响。     

Managing the impact of climate change on the hydrology of the Gallocanta Basin,NE-Spain

The Gallocanta Basin represents an environment highly sensitive to climate change. Over the past 60 years, the Laguna de Gallocanta, an ephemeral lake situated in the closed Gallocanta basin, experienced a sequence of wet and dry phases. The lake and its surrounding wetlands are one of only a few bird sanctuaries left in NE-Spain for grey cranes on their annual migration from Scandinavia to northern Africa. Understanding the impact of climate change on basin hydrology is therefore of utmost importance for the appropriate management of the bird sanctuary. Changes in lake level are only weakly linked to annual rainfall, with reaction times between hours and months after rainfall. Both the total amount of rainfall over the reaction period, as well as individual extreme events, affect lake level. In this study the characteristics and frequencies of daily, event, monthly and bi-monthly rainfall over the past 60 years were analysed. The results revealed a clear link between increased frequencies of high magnitude rainfall and phases of water filling in the Laguna de Gallocanta. In the middle of the 20th century, the absolute amount of rainfall appears to have been more important for lake level, while more recently the frequency of high magnitude rainfall has emerged as the dominant variable.     

Learning about knowledge management for improving environmental impact assessment in a government agency: the Western Australian experience

How does knowledge management (KM) by a government agency responsible for environmental impact assessment (EIA) potentially contribute to better environmental assessment and management practice? Staff members at government agencies in charge of the EIA process are knowledge workers who perform judgement-oriented tasks highly reliant on individual expertise, but also grounded on the agency’s knowledge accumulated over the years. Part of an agency’s knowledge can be codified and stored in an organizational memory, but is subject to decay or loss if not properly managed. The EIA agency operating in Western Australia was used as a case study. Its KM initiatives were reviewed, knowledge repositories were identified and staff surveyed to gauge the utilisation and effectiveness of such repositories in enabling them to perform EIA tasks.     

Priority screening of toxic chemicals and industry sectors in the U.S. toxics release inventory: a comparison of the life cycle impact-based and risk-based assessment tools developed by U.S. EPA

Life Cycle Impact Assessment (LCIA) and Risk Assessment (RA) employ different approaches to evaluate toxic impact potential for their own general applications. LCIA is often used to evaluate toxicity potentials for corporate environmental management and RA is often used to evaluate a risk score for environmental policy in government. This study evaluates the cancer, non-cancer, and ecotoxicity potentials and risk scores of chemicals and industry sectors in the United States on the basis of the LCIA- and RA-based tools developed by U.S. EPA, and compares the priority screening of toxic chemicals and industry sectors identified with each method to examine whether the LCIA- and RA-based results lead to the same prioritization schemes. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) is applied as an LCIA-based screening approach with a focus on air and water emissions, and the Risk-Screening Environmental Indicator (RSEI) is applied in equivalent fashion as an RA-based screening approach. The U.S. Toxic Release Inventory is used as the dataset for this analysis, because of its general applicability to a comprehensive list of chemical substances and industry sectors. Overall, the TRACI and RSEI results do not agree with each other in part due to the unavailability of characterization factors and toxic scores for select substances, but primarily because of their different evaluation approaches. Therefore, TRACI and RSEI should be used together both to support a more comprehensive and robust approach to screening of chemicals for environmental management and policy and to highlight substances that are found to be of concern from both perspectives.     

Optimization of the recovery of plastics for recycling by density media separation cyclones

Material recovery processes are presented as the optimum option for recycling plastic wastes as a means of recovering hydrocarbon resources. There exist a large variety of automated material recovery processes for recycling of such wastes but each with significant limitations. Of these, the separation based on differences in densities is advocated as the optimum process either for producing recycled products or preparing wastes for subsequent recovery processing.Density separation processes based on cyclone type density media separation (DMS) is presented as an important, potential method for increasing plastics recycling process capacities. It is demonstrated to have the capacity to separate a significantly larger range of particle sizes than those presently processed industrially. The mathematical relationship for the prediction of quality of typical LARCODEMS type density media separations by particle size and density as expressed by the Ecart Probable is presented.A proposed device configuration is presented for density media separation to optimize the recovery and purity of both density fractions produced. It is also suggested that to be economically viable, a large scale of operation is required for industrial plastics recycling operations recovering and producing a number of different plastics with a purity to be used as a substitute for virgin material.     

Balancing durability and environmental impact in concrete combining low-grade recycled aggregates and mineral admixtures

This paper investigated the effect of various amounts of low-grade recycled aggregates in concrete containing mineral admixtures at three different water-binder ratios on mechanical and environmental performance. The balance between durability and environmental impact for a given strength level similar to normal-use concrete was also examined using analytic hierarchy process. Results showed that increasing the water-binder ratio and volume of recycled aggregates reduced compressive strength and increased air permeability and drying shrinkage relative to normal aggregates. However, compared to normal-use concrete similar or better performance could be achieved, which was attributed to improvement of low-grade recycled aggregate performance when combined with fly ash. Similarly, CO₂ emissions and volume of raw materials were lower than the normal-use concrete for all mixes. Concrete mixes with low air permeability and low CO₂ footprint had the best balance of durability and environmental impact, as decreasing raw material volume tended to more greatly reduce durability.     

Snorkelling and trampling in shallow-water fringing reefs: risk assessment and proposed management strategy

Shallow reefs (reef flats <1.5 m) in the northern Red Sea are impacted by growing tourism that includes swimmers, snorkellers and reef walkers but have largely been neglected in past studies. We selected a fringing reef along the lagoon of Dahab (Sinai, Egypt) as a model for a management strategy. Point-intercept line transects were used to determine substrate composition, coral community and condition, and the coral damage index (CDI) was applied. Approximately 84% of the coral colonies showed signs of damage such as breakage, partial mortality or algal overgrowth, especially affecting the most frequent coral genus Acropora. Questionnaires were used to determine the visitors' socio-economic background and personal attitudes regarding snorkelling, SCUBA-diving and interest in visiting a prospective snorkelling trail. Experiencing nature (97%) was by far the strongest motivation, and interest in further education about reef ecology and skill training was high. Less experienced snorkellers and divers--the target group for further education and skill training--were those most prepared to financially support such a trail. We therefore recommend a guided underwater snorkelling trail and restricting recreational use to a less sensitive 'ecotourism zone' while protecting the shallow reef flat. Artificial structures can complete the trail and offer the opportunity to snorkel over deeper areas at unfavourable tide or wind conditions. This approach provides a strategy for the management and conservation of shallow-water reefs, which are facing increasing human impact here and elsewhere.     

基于STIRPAT模型的环境压力空间差异分析——以能源消费为例

定量分析区域人文驱动力对环境的影响,对认识我国区域环境压力及其影响因素具有一定的科学意义.利用STIRPAT模型,以人口数量、富裕度为自变量,以能源消费总量为因变量,应用岭回归函数拟合得到环境压力模型.以研究结果为依据.利用Mapinfo7.0 软件分别绘制人口数量和富裕度对环境压力影响的空间差异图.结果显示,不同省份间人口数量和富裕度对环境压力影响存在显著差异.尽管各省份人口数量对环境压力都产生线性正效应影响,但影响强度有明显差异,最大者是最小者的8.079倍.富裕度对环境压力影响,有正效应或者负效应;有线性作用或者弹性作用.30个考察对象中,北京、上海、四川、新疆4个省市的富裕度二次项系数为负,这说明,在数据观测范围内以上4个省市的结果支持富裕度与环境压力间存在倒"U"型环境库兹涅茨曲线的观点;但这4个省市的环境压力并没有出现下降,这是由于各种人文驱动力影响的净效应决定了环境压力变化趋势.人口数量的增长对环境压力的上升存在较强正效应.因此,控制人口数量的速度对改善环境压力将起到关键作用.     

高温条件下高速碰撞试验技术研究

目的建立高温条件下结构的高速碰撞试验技术。方法基于理论和试验方法,研究影响试样加热/保温、碰靶速度和姿态的关键因素,利用次口径发射技术和电炉技术实现试样的加热、保温和加速。采用间接方法测试试样碰靶时的温度,联合应用次口径发射技术和靶体,控制试样的碰靶姿态,并利用高速摄影技术对其进行测试。通过薄壁圆柱筒的高温高速碰靶验证高温试验技术的有效性。结果建立了加热、加速和姿态控制一体化的高温高速碰撞试验技术,获得了不同尺寸薄壁圆柱筒不同姿态碰靶时的高温冲击动力学响应。正碰时,撞击端镦粗,尾端收缩,尾端的凹陷大于碰撞端的变形;侧碰时,圆筒呈马鞍状;角碰时的变形为楔形。随着圆筒的强度和刚度的降低,圆筒的变形增加,整体发生坍塌,出现大量的皱褶。结论建立的试验技术切实有效,可以用于高温条件下结构高速碰撞效应的研究。     

Impact of payments for environmental services and protected areas on local livelihoods and forest conservation in northern Cambodia

The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well‐being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households’ ability to expand and diversify their agriculture. The impacts of PES on household well‐being were related to the magnitude of the payments provided. The two higher paying market‐linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well‐being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people.