Responses of benthic macroinvertebrates to thin-layer disposal of dredged material in Mississippi Sound, USA

Benthic community responses to thin-layer disposal of dredged material were assessed at three sites in Mississippi Sound, USA. Community composition differed between disposal and reference sites (ANOSIM) for each disposal event. Oweniid sand worms, Amphinomid fire worms, and brittle stars (Ophiuriodea) contributed the most to community distinctions between disposal and reference sites (SIMPER), with higher abundances at the disposal sites. Total infaunal abundance was similar to pre-disposal and reference conditions within 3-10 months of thin-layer disposal. Distinctions in community composition between disposal and reference sites (nMDS) persisted throughout the 16-month study period, but were less pronounced at the site where sediment composition was unchanged by disposal. Size distributions of some taxa (e.g., gastropod and hemichordate) suggest adults recolonized the newly deposited sediments either through vertical migration or lateral immigration from adjacent areas. Thin-layer disposal offers a viable alternative to conventional open-water disposal practices and warrants further exploration for other areas with deeper bathymetries and different hydrodynamic regimes.     

洼地开采地下水的地质环境效应研究——以天津市黄港洼应急水源地为例

天津市是我国水资源缺乏、人均占有淡水资源最少的城市之一,也是我国地面沉降最为严重的地区之一。地面沉降现已成为天津市的主要地质灾害,并在一定程度上制约着天津城镇的可持续发展。天津市平原区洼地众多,这些洼地大部分是天津市的湿地分布区。在洼地内建设应急地下水水源地,既可以起到为城区供水,缓解城区的地面沉降,又可以改善洼地生态环境的作用。     

冰雪灾害条件下地质灾害应急抢险处置知识构成分析

知识库是冰雪灾害条件下地质灾害应急抢险决策支持系统的核心,知识库中的知识构成则是整个研究的基础。本文按照产生式规则法的知识表示方式,分别分析了冰雪灾害条件下地质灾害应急抢险处置知识的前提及结论部分的主要构成内容,并总结了应急抢险处置措施选择应该遵循的基本原则,另外还给出了根据知识构成抽取具体知识的范例,为冰雪灾害条件下地质灾害应急抢险知识库及决策支持系统的建立提供了基础性研究成果。     

Modeling and representation for earthquake emergency response knowledge: perspective for working with geo-ontology

Earthquake emergency response is one of the three earthquake disaster mitigation work systems in China, already achieving good results in some earthquake disaster mitigation situations. Earthquake emergency plans and emergency command systems are among the most important research and operations components of emergency response. These components commonly come with challenges, such as the pertinence of emergency commands and the operability of the countermeasures to be improved. The promise for solving this problem resides with applying knowledge that aids intelligence creation for decision-making. In this paper, we put forward a conceptual model of knowledge for earthquake disaster emergency response (EDER); compositions of EDER knowledge are introduced within architecture. A modeling method incorporating geo-ontology is used to build basic modeling primitives. Geo-ontology serves to represent geospatial characteristics of the EDER knowledge and addresses a need for semantic interoperability in the modeling process. A decision problem framework and a case study have been used as theoretical framework and an application test, respectively, to evaluate the EDER knowledge architecture and models. The EDER knowledge model provides a foundation for intelligent emergency response that helps solve knowledge problems to improve earthquake disaster response.     

Airborne near-real-time monitoring of assembly and parking areas in case of large-scale public events and natural disasters

A critical requirement for an effective and coordinated response by public entities tasked with management, security, and relief during large-scale public events or natural disasters is the availability of current situational information. However, today there is a lack of comprehensive operational systems allowing a near-real-time (NRT) collection, visualization, and provision of situational information for larger areas. In this study a methodological framework is proposed, which allows an NRT extraction and visualization of situational information based on aerial image acquisition. The framework combines digital image analysis using a generic supervised information extraction approach based on statistical modeling with a downstream web-based visualization component realized through an automatic update of web services. Even though being applicable for different scenarios, the workflow will be demonstrated for the specific use-case of a NRT monitoring of open spaces including assembly and parking areas. Compared to other approaches, image analysis results indicate a high robustness and a low demand for computational power sources (7 seconds per image). Due to a high degree of automation, the proposed workflow contributes to a NRT ‘end-to-end’ monitoring system, which was developed within the VABENE (German acronym for ‘traffic management under large-scale public events and disaster conditions’) project covering all parts from the acquisition of raw aerial imagery to the dissemination of information products to end-users.     

高放废物地质处置北山预选区旧井和新场花岗岩填隙方解石同位素地球化学

为了探讨高放废物地质处置甘肃北山预选区旧井和新场预选地段的古地下流体来源、成因、化学演化历史以及水-岩相互作用,文章系统研究了该地段花岗岩填隙方解石的产出特征及其碳、氧、锶同位素的组成特征。测试结果表明,旧井和新场方解石的δ13 C组成均较稳定且为负值(分别为-11.6‰~-5.7‰和-9.9‰~-5.1‰);δ18 O分别为-0.7‰~19.7‰和10.9‰~21.9‰,旧井方解石具有更宽的δ18 O取值范围。87 Sr/86 Sr也略有差异,旧井为0.708584~0.718749,新场为0.708838~0.732967,二者随深度增加而呈明显的降低趋势。研究表明,北山预选区地下流体来源及成因较复杂,浅部地下水受大气降水的影响较大,深部流体则主要源于地下咸水,为低温流体蚀变成因。花岗岩裂隙中的水-岩反应强度总体较弱,地下水环境相对稳定。相比较而言,新场岩体深部的地球化学环境更稳定,更有利于高放废物的长期处置。     

微量污染物应急及在线监测技术在珠江流域水源地的应用

法国AQUAPOD Light分析仪和AQUAPOD case应急监测仪用于微量有毒有机物和常规水质参数的在线监测,可对未知有机污染物发出报警,是实用性很强的微量污染物在线监测技术手段。基于该系统已建立了17个珠江流域特征有毒污染物的在线监测模型,将其应用于珠江重点饮用水源地,并对数据模型进行了检验;系统还具备常规参数的监测能力,其对COD、TOC和硝酸盐类等污染物监测的数据经与实验室内测试结果相比较,数据误差分布的检验结果表明其准确度和精密度均较好。     

新疆地震应急基础数据的处理和建库

介绍了新疆地震应急基础数据库的构成、数据处理和建库及数据库在地震应急指挥技术系统中发挥的作用等。解决了多源数据的处理和整合、多种数据库之间的协同和关联、海量数据的集成等问题。     

楼宇内部路径规划算法研究及其应用综述

在人群密集的大型楼宇,构建基于楼宇内部空间三维拓扑结构的逃生疏散路径,是当前路径规划算法研究的难点和热点。本文对当前常见的路径规划算法进行优劣对照比较,并详细阐述其在楼宇内部逃生疏散场景应用的算法思想和主要特征,最后总结了楼宇内部路径规划算法研究的发展方向。     

Analysis of the FEBEX multi‐barrier system including thermoplasticity of unsaturated bentonite

Deep geological repository involving a multibarrier system constitutes one of the most promising options for isolating high‐level radioactive waste from the human environment. To certify the efficiency of waste isolation, it is essential to understand the behaviour of confining geomaterial under a variety of environmental conditions. To this end, results from a near‐to‐real experiment, the full‐scale engineered barriers in situ experiment, are studied by means of a thermo–hydro–mechanical finite element approach, including a consistent thermoplastic constitutive model for unsaturated soils. Laboratory tests are simulated to calibrate model parameters. The results of the numerical simulations are compared with sensor measurements and show the ability of the model to reproduce the main behavioural features of the system. The influence of the hysteretic and temperature‐dependent retention of water on the mechanical response is exhibited. Finally, those results are interpreted in the light of thermoplasticity of unsaturated soils, which reveals the highly coupled and non‐linear characters of the processes encountered. Copyright © 2011 John Wiley & Sons, Ltd.