长江口溢油数值模拟及对水源地影响

首先建立了一套基于非结构网格的长江口-杭州湾二维垂向平均潮流数学模型,又基于最新的实测资料重点对南支水域流速、流向和水位进行验证,充分证实了模型的可靠性。在潮流模型可靠的基础上为MIKE21 SA(溢油模块)提供水动力基础数据,建立了一套基于欧拉 拉格朗日体系的“油粒子”追踪技术,综合考虑油膜扩展、输移和风化过程的长江口溢油行为与归宿预测模型。并对长江口夏季和冬季大潮溢油事故发生后取水口油膜厚度的变化及油膜运动路径进行了模拟预测。研究表明：油膜在长江口受到往复流形式的涨落潮交替作用,油膜沿深槽向下游震荡漂移;〖JP2〗油膜在纵向上逐渐被拉伸,形成窄长的油带,覆盖面积逐渐增大;油膜的运动轨迹除了受到涨落潮流的主控外还易受风况和长江口水下地形等影响;夏季溢油对3个水库均有不同程度的影响,冬季溢油只威胁到陈行水库的取水;夏季油膜蒸发量大于冬季     

Chemical treatment of oil spills

Chemical treatment methods have been used with varying degrees of success for mitigating the environmental effects resulting from oil spills. These methods include dispersing, herding, and gelling a floating oil slick; sinking the oil; burning the oil mass either on open waters or on the affected shoreline; and applying film-forming chemical agents to protect shorelines from oil than eludes offshore cleanup. The latest technical information on the applicability and effectiveness of these approaches for treating and controlling oil spills is presented.     

Simulation of the dispersion of nuclear contamination using an adaptive Eulerian grid model

Application of an Eulerian model using layered adaptive unstructured grids coupled to a meso-scale meteorological model is presented for modelling the dispersion of nuclear contamination following the accidental release from a single but strong source to the atmosphere. The model automatically places a finer resolution grid, adaptively in time, in regions were high spatial numerical error is expected. The high-resolution grid region follows the movement of the contaminated air over time. Using this method, grid resolutions of the order of 6 km can be achieved in a computationally effective way. The concept is illustrated by the simulation of hypothetical nuclear accidents at the Paks NPP, in Central Hungary. The paper demonstrates that the adaptive model can achieve accuracy comparable to that of a high-resolution Eulerian model using significantly less grid points and computer simulation time.     

钉螺的水力输送

血吸虫病是中国和其它许多国家的一种地方性流行病,钉螺是血吸虫唯一的中国宿主,钉螺运移是血吸虫病蔓延的主要原因。研究钉螺在河道中的输移规律,对控制血吸虫病流行十分重要。野外观测和实验研究表明、钉螺输移、尤其是大量钉螺的远距离输移,是借助于水流完成的,河流中钉螺的水力输送主要是以悬移质和移质的形式,以及被漂的挟带。     

The Amoco Cadiz oil spill. Distribution and evolution of hydrocarbon concentrations in seawater and marine sediments

The shipwreck of the Amoco Cadiz supertanker on the rocks of the Brittany Coast of France (March, 1978) was one of the most disastrous oil spills ever recorded. The crude oils discharged in the marine environment were light petroleums. The distribution and the evolution of the oil pollution in the marine environment was examined. Chemical studies were limited to an overall estimate of the oil content to assess the importance and the extent of the pollution at the surface, in the water column, and in the sediment. UV fluorescence spectroscopy was used to detect oil in the seawater samples and IR spectrophotometry was used to analyze the sediment samples. Hydrocarbon concentrations in seawater ranged from 0.5 μ/1 to more than 100 μg/1. The oil spill has affected a very large section of the western English Channel. The diffusion of the hydrocarbons into the water column was observed. The evolution of the seawater pollution was followed, and the half-life of hydrocarbons in subsurface water was found to be between 11 and 28 days in different areas. One month after the disaster, the marine sediments were contaminated in the areas reached by the drifting slicks. The highest accumulation of petroleum in the sediments was located in the sheltered coastal environments. The natural decontamination process was found to be related to the nature of the sediment and the energy level of the geographic zone.     

Atmospheric transport patterns and possible consequences for the European North after a nuclear accident

The main purpose of this study is to examine possible impacts and consequences of a hypothetical accident at the Kola nuclear plant in north-west Russia on different geographical regions: Scandinavia, central Europe, European FSU and Taymyr. The period studied is 1991-1996. An isentropic trajectory model has been used to calculate forward trajectories that originated over the nuclear accident region. Atmospheric transport patterns were identified using the isentropic trajectories and a cluster analysis technique. From the trajectory model results, a number of cases were chosen for examination in detail using more complete transport models. For this purpose, the models MATHEW/ADPIC, DERMA and a newly developed FOA Random Displacement Model have been used to simulate the radionuclide transport and contamination in the case of a nuclear accident and their results have been compared with those of the trajectory modelling. Estimation of the long-term consequences for populations after an accident has been performed for several specific dates by empirical models and correlation between fallout and doses to humans on the basis of the Chernobyl accident exposures in Scandinavia.     

A process-based model for the partitioning of soluble, suspended particulate and bed sediment fractions of plutonium and caesium in the eastern Irish Sea

A dynamic model of plutonium behaviour in the marine environment has been developed, representing the oxidation state distribution and partitioning of plutonium between the soluble, colloidal, suspended particulate and seabed sediment fractions. With simple re-parameterisation, this model can also be applied to (137)Cs. The model, which is calibrated and validated against field data, has been used to predict concentrations of Pu(alpha) and (137)Cs in both water and seabed sediments from the vicinity of the Sellafield Ltd. reprocessing plant in Cumbria, UK. The model predicts that sediment reworking and transport are the key environmental processes as the Sellafield Pu(alpha) and (137)Cs discharge continues to decline. Inventory calculations generated by the model are consistent with previous estimations. For a hypothetical post-discharge scenario, the concentrations of these radionuclides in both seawater and surface sediments are predicted to decrease sharply, concurrent with a downward vertical migration of the activity retained in sediments.     

A modeling analysis of the sustainability of ecotourism in Belize

Over the past two decades, ecotourism has emerged as an important conservation strategy, especially in the Tropics where a diversity of species and habitats are threatened by traditional forms of development. However, questions remain about the sustainability of ecotourism in terms of distributions of income to local people and degradation of ecosystems visited by the ecotourists. In this study, a computer simulation model was used to study the possible long-term patterns of ecotourism at the country scale for Belize, Central America. The model includes state variables for natural ecosystems and tourism infrastructure with a submodel for global oil supply. It was simulated over a 100-year period as an EXCEL spreadsheet with a time step of 1?year. In all of the simulations, a decline over time in income from ecotourists was found due to increases in the price of oil and due to environmental impacts by tourism. Conservation efforts can slow the declines, but ultimately, the system is shown to be unsustainable. The results are discussed in the context of long-term conservation potential in Belize.     

Environmental movement in Lebanon

The paper reviews and assesses the evolution of the environmental movement in both the public and the private sector in Lebanon. It studies the public sector involvement in the environmental movement by reviewing the commitments made by the government to the local, regional and international communities. The paper presents a summary of all the decisions, decrees, and laws pertaining to environmental protection that the Lebanese government has instituted over time, as well as all the conventions and agreements that the country has ratified and/or signed. Compared to the Arab world in the Middle East and North Africa, Lebanon is relatively more active and integrated in the world community. Using the total number of established environmental organizations and the level of reported activities aimed at spreading environmental awareness and educating people as indicators of private sector involvement in the environmental movement, the paper concludes that the post war era is characterized by a significant increase in the number of established organizations. It also concludes that there is a co-movement between economic and environmental variables. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

基于WebGIS三峡干流水质模拟平台研究

三峡蓄水成库后仍属于典型的河道型水库,其总体水流、水质运动特性符合一维水流水质运动规律。针对三峡库区总体水流、水质运动特性,采用一维水流水质模型对三峡库区水流和水质进行了模拟。以该模型为核心,利用Web Services技术开发并在互联网上发布了模型服务,在此基础上采用成熟的WebGIS和富客户端Flex等技术构建了适用于三峡库区的干流水质模拟平台;能够实现包括各计算断面流速、流量、水位以及污染物浓度时空过程在内的三峡库区干流流速场和浓度场的数值模拟。以库区干流清溪场至十里铺断面内的江段作为模拟实例,利用该平台模拟计算江段内水流和水质状况,并以水文水质同步观测数据对模拟结果进行验证,结果表明其具有较好的模拟效果;为三峡库区污染物总体输移扩散特性研究提供了有利工具,同时也为国家和地方政府进行库区水环境决策提供了技术支持     

Divergence in stakeholder perception of sustainable remediation

The modern society is increasingly demanding sustainable practices in engineering fields. In the specific case of engineering practices for restoring contaminated land, there is an ongoing sustainable remediation movement which has rapidly drawn attention from both the industry and governments. It is well recognized that decision making in contaminated land remediation depends on the interaction of a variety of stakeholders. However, there is still no consensus as for how various stakeholders perceive sustainable practices in remediation, and how stakeholders interact in decision making that may lead to sustainable practices. The present study proposes a hypothetical model depicting the mediating effect of stakeholder perception in decision making. Using empirical experiences, questionnaire survey, and qualitative interview results, the present study found that there is divergent perception by various stakeholders regarding how sustainable behavior is adopted and how it is affected by stakeholder influence. The divergent view was attributed to varying organizational objectives, information access, and self-perception. Moreover, it found that incorporating sustainability into real engineering practice is transdisciplinary and requires transdisciplinary processes that can help various stakeholders to reach consensus.     

State of the art in high sea-state oil pollution response capabilities

This paper describes the state-of-the-art approaches to dealing with the two major types of open-water pollution incidents encountered in bad weather — a tanker stranding where the oil is still contained within the tanks, and an actual spillage from a damaged tanker or fixed source.In the stranding case, the cargo off-loading approach is compared with cargo jettisoning (pumping part of the cargo overboard) and stabilization approaches.In the spillage case, the basic approaches that are feasible are skimming and the use of dispersants. The advantages of each are discussed. Systems including large containment barriers are estimated to be less effective than direct-acting skimmers because of the operational control problems in high sea states. Effective direct-acting skimmers are not in wide-spread use at present, although several systems are under development. Dispersant systems are estimated to have the highest sea-state operating capability, particularly aircraft-application systems, which could be effective in conditions up to where a slick is rapidly dispersed through natural wave turbulence.     

能源价格变动对中国节能降耗的影响效应

在分析我国能源比价扭曲对能耗强度影响效应的基础上,建立了Bayesian时变动态回归模型,测算了能源价格变动对能耗的影响效果及变动趋势。主要结论为:①能源比价关系的调整比单种能源价格的国际接轨更为重要。相比国际市场的能源比价结构,中国能源商品价格结构的扭曲度提高了中国的能耗强度,促进了第二产业的增长。②能源价格的变动对单位GDP能耗的影响效应具有显著的时变特征。在电力、煤炭、石油三种能源中,电力价格的变动对能耗强度的影响最大。电力价格变化对单位GDP能耗的影响边际效应在逐年下降,但节能的效果仍很显著。煤电价格联动制约及"从量计征"的资源税偏低使得煤炭价格的上涨反而加大了能耗强度,且1996年以来煤炭价格的提高对单位GDP能耗上升的影响效应还在不断加强,原油价格的提高对单位GDP能耗的影响在不同的时间段有不同的作用,但相对煤炭及电力价格来说,石油价格的影响效应最小。2002年以前石油价格的上升对能耗的上升起助推作用,2003年后石油价格的上升对能耗的上升起降低作用且强度逐年加大。     

Collection efficiency of electrostatic precipitators by numerical simulation

A numerical simulation code has been developed to analyze the coupled electro-aerodynamic phenomena within an electrostatic precipitator operated in both the positive and negative corona modes. The space charge and current densities, as well as the static and space charge components of the electric field, are first obtained using the known cross-sections for ionization and negative ion formation. Data includes the effects of fluid flow. The above quantities (except the static field) are then corrected in a subsequent iteration for the presence of dust particles of known size distribution, charges predominantly by the field charging mechanism. The precipitator collection efficiency is calculated from the trajectories of the charged dust particles. For theory comparison, the collection efficiencies of model precipitators were measured by light-scattering techniques using oil drops as test particles. The variation of efficiency with wire-to-wire spacing will be discussed as a case study.     

Achieving sustainability in manufacturing via organisational and operational learning

The contribution contained in this paper focuses on providing a possible framework or approach in respect of how manufacturing companies can economically introduce environmentally friendly practices to their production operations, whilst at the same time encouraging organisational and operational learning with the aim of eventual evolution of the firm into an eco-efficient concern. A key premise associated with the approach advocated is economical organisational and operational learning over time, thus providing a sequential movement of the company through various stages of cultural change and technological capability to eventually achieve eco-efficiency in its production activities. At each stage in the process, it is suggested that a balance must be maintained between on the one hand, a reduction in operational economics consistent with on the other hand, an improvement in the environmental sustainability of company activities. To that end, some previously suggested monitoring metrics are examined in the text for their efficacy and economic rapport via hypothetical examples of how they might be applied in practice to monitor movement towards industrial–environmental sustainability.     

Inside and beyond the Petro-State frontiers: geography of environmental conflicts in Venezuela’s Bolivarian Revolution

Venezuela is well known for its century-old oil economy, which has significantly shaped its social fabrics, territories, and eco-systems. Since 1999, the Bolivarian Revolution has led to important transformations in the context of the ‘Socialism of the 21st century’ project, but the extractivist model has deepened. This situation has created or intensified several ecological distribution conflicts, which have been further exacerbated by an extraordinary national crisis unleashed in the period 2013–2016. In this paper, a geography of the 20 most emblematic and representative socio-environmental conflicts in the period of the Bolivarian Revolution is presented. From a comparative political ecology perspective, this article aims to understand how power relations are expressed through territorial configurations and spatial dynamics of resistance, and what are the implications for sustainability. It is argued that a remarkable new situation of environmental injustice is occurring in this period. Despite the ‘eco-socialist’ discourse raised, the current Petro-State has updated the traditional regime on eco-systems, territories, and human bodies primarily by resorting to the assimilation of socio-environmental conflicts through a strategic distribution policy of oil rents. However, it has maintained a pattern of ecological degradation and social marginalization as an outcome of its economic development model. The current context of crisis has fostered intense territorial disputes and conditions for the emergence of new social actors, practices, scenarios, and geographies linked to underground economies and criminal bands, which complicate an already concerning scenario of unsustainability. The current extractivist model is reaching a breaking point. New commodity frontiers have become a main area of dispute.     

气候变化对西苕溪流域未来洪水影响研究——Ⅱ.情景分析

研究表明VIC模型在西苕溪流域具有良好的适用性,特别是对汛期洪水的模拟。应用陆面水文模型VIC与区域气候模式PRECIS耦合,探讨了西苕溪流域未来洪水对气候变化的响应。结果表明：横塘村水文站月平均流量与月最大洪峰流量的关系较为密切,相关系数均在0.85以上,在一定程度上可以表征洪水的变化特征;基于PRECIS生成的气候情景,未来时期西苕溪流域洪水对气候变化的响应比较明显,尤其是汛期流量增加趋势较显著;结合P-Ⅲ型分布频率分析,西苕溪流域2021~2050年发生洪水极值事件的频率及量级都较基准期增大,且A2情景比B2情景相对更容易触发较大洪水,基准期50 a一遇洪水在未来两种情景下分别缩短为27 a一遇和32 a一遇,说明流域洪水对于气候变化的响应程度增大。     

Modelling and analysis of sustainable manufacturing system using a digraph-based approach

Abstract

Sustainable manufacturing practices have many benefits like cleaner production, resource efficiency along with economic benefits. Sustainable manufacturing practices focuses on four dimensions environment, economy, business and society. The effective deployment of sustainable concepts mostly depends on interaction of these sustainable dimensions. In this study, an attempt on assessment through modelling has been presented. Mostly two factors determine the sustainable performance of organisation: the performance of the criteria is identified under four dimensions (inheritance) and their interaction (interdependency) among each other. Thus, graph theory-based modelling has been done considering both inheritance and interdependency for computing Overall Organisation Sustainability (OOS) score. Finally, permanent scores for matrices obtained from experts’ team have been computed. OOS score for the organisation has been computed and is compared with the scores of hypothetical scenarios. Through the comparison with hypothetically generated practical best and worst-case scenario, insights have been derived.     

我国外来入侵动物的扩散风险分析及分级管理

外来入侵动物给我国的生物多样性、国民经济以及人类的健康带来了严重危害,正确分析外来入侵动物的扩散风险对控制其在国内的扩散有着极其重要的意义。采用层次分析法,建立了外来动物扩散的风险评估指标体系,并选取食人鲳〖WTBX〗（Pygocentrus nattereri）、桔小实蝇（Bactrocera dorsalis Hendel）〖WTBZ〗等几种典型的外来入侵动物作为评估对象,通过扩散风险计算模型评估出扩散风险的大小,设置阈值对不同入侵动物的扩散风险进行了分级,最终将外来入侵动物的风险分为4个等级：极高风险、高风险、中风险以及低风险,并针对不同风险等级不同扩散程度的外来动物提出了相应的分级管理对策,以期提高政府管理外来入侵动物扩散的效率     

Performance assessment studies of models for water flow and radionuclide transport in vegetated soils using lysimeter data

Increasingly the burial of nuclear waste in deep underground repositories is being regarded as a safe long-term solution for disposal. However, to support this safety assessment models of the associated risks are required. An important component of these models is the upward migration of radionuclides from a contaminated water table into arable and pasture crops. A five-year experiment to investigate the processes which control these transfers has been undertaken at Imperial College. Selected data from this experiment were made available to participants of the BIOMOVS II programme in order to allow them to perform blind hydrological and radionuclide transport simulations. The results show the importance of correctly characterising the soil hydrology and indicate that model conceptualisations derived from surface contamination studies may not adequately capture the various processes which influence the upward movement of radionuclides in the vadose zone. These include not only the water movement, but also chemical and biological processes. Finally, the difficulty and importance of a priori parameter selection is highlighted.