Identification and ranking of the risky organic contaminants in the source water of the Danjiangkou reservoir

The Danjiangkou reservoir was selected to provide the source water for the middle routes of the South to North Water Transfer Project, which has provoked many environmental concerns. To date, investigations of water contamination of the source water of the Danjiangkou reservoir with organic micro-pollutants have been limited. This study was conducted to identify and rank organic contaminants that pose risks in the Danjiangkou reservoir. To this end, the Chemical Hazard Evaluation and Manage- ment Strategies （CHEMS-1） approach was adapted to integrate the deconvolution technology of qualitative identifying contaminants for site-specific environmental matrices. The samples were screened for the presence of 1093 contaminants using deconvolution technologies and the hazard values of the identified contaminants were calculated using the adapted CHEMS-1 approach accord- ing to their hazardous properties and occurrence in source water. The results showed that 46 contaminants from 1093 targets were present in Danjiangkou water, 23 of which appeared at frequencies higher than 50%, and 15 of which were identified as priorities. Over half （53%） of the high- ranked contaminants were polycyclic aromatic hydrocar- bons （PAHs）, with chrysene ranked highest on the list. Health risk assessment of the top-ranked PAHs was conducted and revealed that cancer risks of PAHs detected in the source water of Danjiangkou to different populations ranged from 10-7 to 104, indicating a low cancer risk to consumers. The results of this study indicated that the adapted CHEMS-1 approach was feasible for site-specific screening of organic contaminants to identify and rank potential priority pollutants.     

三峡工程对洞庭湖水力梯度及其湿地植物生长的影响

水力梯度是制约洞庭湖湿地植物生长的主要因素.通过分析三峡水库运行前后洞庭湖水力梯度的变化来研究其对洞庭湖湿地植物的影响,能为该区植物多样性及退化生态系统的恢复提供科学依据.研究表明,三峡工程的运行不同程度上降低了洞庭湖的水力梯度,且枯水期的影响大于丰水期.其中东洞庭湖受其影响最为明显,特别是在4月和10月,洞庭湖其他地段水力梯度变化较为平稳.三峡工程对洞庭湖湿地植物的影响是枯水期大于丰水期,除了4月和5月对洞庭湖湿地植物的生长产生不利的影响外,其他月份有着有利的影响或影响不大.     

Investigation of stakeholders' awareness and adoption of Inherently Safer Design (ISD) principles in South African utility industry projects

The paper examines the level of awareness of stakeholders in adopting Inherently Safer Design (ISD) principles in the Project Life Cycle Management (PLCM) of South African Energy utility projects. It seeks to understand whether stakeholders in the latter stages of the Project Life Cycle are competent to make design change decisions on these projects. ISD principles are essentially useful for reducing risks and as such, safety experts have acknowledged it as an excellent approach in the design process. However, there are no known efforts to date that attempt to integrate ISD concepts into PLCM. This paper seeks to fill this gap. This study, through the review of extant literature establishes that ISD principles can be used in project procurement, and adopts a quantitative survey approach in obtaining information from stakeholders in the South African utility industry. Findings reveal that the principles of inherent safety are permeating into the management of South African utility projects but the level of awareness and its adoption are below optimal levels. It also emerged that there is a divergent awareness of ISD strategies amongst PLCM stakeholders and that the design engineers are better informed about the ISD approach of eliminating risks and hazards in the industrial systems studied than other stakeholders. The findings also indicate that the level of awareness of stakeholders of ISD principles is greater within earlier project phases. Based on these findings, the paper concludes that the hazards witnessed within the project execution and finalization phases could be as a result of the low levels of awareness, divergent views and lower use of ISD strategies by PLCM stakeholders. It is suggested that the level of awareness of the principles, concepts, basics and benefits of integrating ISD into PLCM be raised amongst stakeholders functioning within utility industry project procurement in South Africa and that design changes be limited to the earlier phases of utility project procurement.     

退耕还林工程对四川盆周低山丘陵区生态系统服务价值的影响——以洪雅县为例

退耕还林工程是我国实施的重点林业生态工程。以四川盆周低山丘陵区退耕还林工程重点示范县洪雅县为研究对象,基于遥感和地理信息系统技术,参照中国陆地生态系统单位面积生态系统服务价值当量表,结合研究区粮食平均产量和收购价格,分析了退耕还林前(1994-1999年)、后(1999-2007年)的生态系统服务价值变化,探讨了退耕还林工程对生态系统服务价值的影响。结果表明:退耕还林工程在一定程度上使土地利用程度呈减弱趋势,土地利用处于衰退阶段;退耕前,生态系统服务价值变化不明显;退耕后,生态系统服务价值发生显著变化,总生态系统服务价值增加2.90×10⁸元,可能是由于退耕还林使耕地生态系统服务价值降低,林地生态系统服务价值增加;各项生态功能服务价值中,食物生产功能价值下降,其它各项功能价值上升,以水源涵养功能上升最大,水源涵养价值增加0.78×10⁸元;敏感性分析表明,研究区生态系统服务价值对生态系统服务价值系数变化缺乏弹性,研究结果具有稳定性。     

引滦工程上游浮游植物及其水质评价

对引滦入津工程沿线上游水域进行浮游植物种类区系组成、现存量(密度、生物量)及分布等内容进行了调查研究,并结合历史资料和国内相似水体研究结果的分析,对调查水域进行了水生态环境质量评价。结果表明,调查水域整体上可初步划定为中营养型,水质状况尚好。但下游的潘家口和大黑汀水库网箱养鱼的发展一定程度上影响了局部水域,由此引起的水体富营养化趋势应引起足够的重视。      

Efforts to Reduce Mortality to Hydroelectric Turbine-Passed Fish: Locating and Quantifying Damaging Shear Stresses

Severe fluid forces are believed to be a source of injury and mortality to fish that pass through hydroelectric turbines. A process is described by which laboratory bioassays, computational fluid dynamics models, and field studies can be integrated to evaluate the significance of fluid shear stresses that occur in a turbine. Areas containing potentially lethal shear stresses were identified near the stay vanes and wicket gates, runner, and in the draft tube of a large Kaplan turbine. However, under typical operating conditions, computational models estimated that these dangerous areas comprise less than 2% of the flow path through the modeled turbine. The predicted volumes of the damaging shear stress zones did not correlate well with observed fish mortality at a field installation of this turbine, which ranged from less than 1% to nearly 12%. Possible reasons for the poor correlation are discussed. Computational modeling is necessary to develop an understanding of the role of particular fish injury mechanisms, to compare their effects with those of other sources of injury, and to minimize the trial and error previously needed to mitigate those effects. The process we describe is being used to modify the design of hydroelectric turbines to improve fish passage survival.     

秦岭生态补偿理论研究与实践进展

生态补偿是通过经济手段促进生态保护与受益地区利益共享的制度设计,是促进我国生态文明建设的重要举措。秦岭是我国重点生态功能区,国家重要的生态安全屏障。生态补偿作为协调秦岭地区生态环境保护和社会经济发展的制度安排,有助于推动该区生态环境的保护与可持续利用,对实现秦岭地区社会经济可持续发展、促进人与自然和谐共生具有重要意义。本文系统梳理了秦岭生态补偿相关理论研究与实践,主要包括秦岭在区域调水、森林生态效益、生物多样性保护、矿产资源开发等方面的生态补偿研究,以及秦岭生态补偿相关政策法规制定、南水北调、退耕还林（草）以及生态移民搬迁等具体生态保护工程补偿实践,并从补偿对象、补偿标准、公众参与、补偿方式几个角度探讨了秦岭生态补偿存在的问题,提出了秦岭生态补偿研究的建议与对策。     

南水北调中线工程水源区蒸散发计算方法比较及影响因素分析

以南水北调中线工程水源区为研究区域,采用1961~2007年9个气象站点气象观测数据和黄家港水文站实测径流资料,以FAO彭曼蒙特斯公式和水文模拟法为标准分别对多种潜在蒸散发计算方法和实际蒸散发计算方法进行比较研究,并分析了陆面蒸散发的影响因素。研究表明：南水北调中线工程水源区存在“蒸发悖论”现象,Priestley Taylor公式计算结果偏大,但与FAO 彭曼蒙特斯公式存在良好的相关关系,在气象资料较少时可以考虑建立相关方程进行推求。傅抱璞公式与水文模拟法计算结果较为接近,相关关系最优。潜在蒸散发与平均温度、气温日较差、实际水汽压、降雨量、风速、净太阳辐射、日照时数呈正相关,而实际蒸散发与平均温度、气温日较差、实际水汽压、降雨量、净太阳辐射、日照时数呈正相关,与风速呈负相关。净太阳辐射是影响陆面蒸散发的核心因素     

长江新滩滑坡的历史分析，趋势预测与启示

从对新滩滑坡的历史回顾分析入手,得出新滩滑坡具有时空上的周期性和继承性规律。着重阐述了１９８５年６月１２日新滩滑坡的形成过程,分析了其机理和形成原因,并由此得出对三峡库区滑坡灾害在治理上的重要启示。