Wind and Wave Data Analysis for the Aegean Sea - Preliminary Results

In this paper, a statistical analysis on wind and wave buoy measurements and wind and wave model forecasts obtained during a two-year period (1999-2001) is presented with reference to four characteristic near-shore sites of the Aegean Sea. The measurements are a main product of the "POSEIDON" system aiming at the monitoring and forecasting of the state of the Greek seas, operated by the National Centre for Marine Research (NCMR). Although the two-year period is rather short for a thorough analysis of the local wind and wave climate, yet the obtained results, presented herein for the first time, reveal some interesting features of the corresponding wave and wind characteristics. Comparisons between the measurements and the forecast results are also performed at the locations under consideration. It is found that (i) wind speeds obtained from the POSEIDON weather forecasting system are, in general, in agreement with the measurements, except for high wind speeds which are systematically underestimated, (ii) the WAM model can successfully follow the monthly and over year trend of the evolution of wind and wave characteristics, but face significant problems for efficient sea-state forecasting. Finally, the overall pattern of the wind/wave climate for the entire Aegean Sea as obtained from the models is presented by means of the spatial distribution of the mean annual wind and sea-state intensity.     

基于GIS技术的地质灾害风险分析系统研究

地质灾害的社会经济属性决定了对其规律的研究应有别于传统的工程地质学研究 ,从社会属性方面来分析地质灾害具有更大的社会经济效益。地质灾害的危险性和受威胁对象的易损性是控制地质灾害风险评价的基本条件 ,对这两者的分析评价称作地质灾害危险性评价和社会经济易损性评价。GIS技术支持下的地质灾害风险分析代表着地质灾害研究领域的一个重要发展方向。经过多年研究 ,作者开发出了基于商业GIS软件的区域地质灾害风险分析系统 (RiskAnly)。本文介绍了该系统的设计思路、基本结构和工作过程 ,并利用此系统对我国全国范围的滑坡灾害进行了危险性分析、区域社会经济易损性分析和最终的风险评估。     

Landslide risk assessment and management: an overview

Landslides can result in enormous casualties and huge economic losses in mountainous regions. In order to mitigate landslide hazard effectively, new methodologies are required to develop a better understanding of landslide hazard and to make rational decisions on the allocation of funds for management of landslide risk. Recent advances in risk analysis and risk assessment are beginning to provide systematic and rigorous processes to enhance slope management. In recent years, risk analysis and assessment has become an important tool in addressing uncertainty inherent in landslide hazards.This article reviews recent advances in landslide risk assessment and management, and discusses the applicability of a variety of approaches to assessing landslide risk. Firstly, a framework for landslide risk assessment and management by which landslide risk can be reduced is proposed. This is followed by a critical review of the current state of research on assessing the probability of landsliding, runout behavior, and vulnerability. Effective management strategies for reducing economic and social losses due to landslides are described. Problems in landslide risk assessment and management are also examined.     

吉林省发展绿色食品的农业生态环境优势分析

发展绿色食品生产是吉林省实施“生态省”建设工程的主导产业之一，本文按照绿色食品产地环境质量标准要求，客观评价了吉林省发展绿色食品的产地环境条件，得出吉林省具有发展绿色食品生产的显著农业生态环境优势。基于吉林省良好的农业生态环境质量，结合区域自然条件和资源优势，将全省分为东部山区、中部松辽平原区、西部松嫩平原区和大、中城市郊区四种区域类型，并分别提出了其发展绿色食品生产的宏观策略。     

河流水质风险评价的灰色-随机风险率方法

提出了量化影响河流水质的随机不确定性与灰色不确定性的水质超标灰色－随机风险率概念，建立了水质超标灰色－随机风险率评价模型。在水质单项参数评价模型中，将河流污染物浓度变量的分布处理成灰色概率分布，将污染物浓度超过水质类别标准值的风险率处理成灰色概率，即水质超标灰色－随机风险率。在水质综合评价模型中，河流水环境系统被考虑为担任某一使用可能的可靠性系统，而任意一种水质参数超标意味着河流水体使用功能不能得到应有的保证，也即表明水体综合评价超标，最后借鉴系统可靠性分析的理论和方法计算水质综合超标率。该方法应用于黄河花园口断面重金属污染风险评价。     

Fire Severity,Water Repellency Characteristics and Hydrogeomorphological Changes Following the Christmas 2001 Sydney Forest Fires

Soil water repellency can enhance overland flow and erosion and may be altered by fire. The Christmas 2001 bushfires near Sydney allowed investigation of the relationship between fire severity, water repellency and hydrogeomorphological changes. For two sub-catchments with differences in fire severities in Nattai National Park, south-west of Sydney, this paper considers: (1) the links between fire severity based on SPOT image analysis and ground observation of fire severity and repellency; (2) the textural and organic/minerogenic characteristics of eroded sediment; and (3) erodibility, erosion and deposition of soils in both catchments. Ground surveys show that image analysis reflects well the degree of vegetation consumption by fire, but cannot adequately predict the degree of ground litter consumption, associated soil heating and repellency effects. Fire had varying effects on repellency, leaving it unchanged, destroying it or enhancing it, depending on the soil temperature reached. The main post-fire hydrogeomorphological changes have been widespread erosion and colluvial and alluvial deposition of topsoil in foot-slope locations and river systems, but only localised redistribution of the highly erodible, repellent sandy subsurface layer. The fire did not trigger major geomorphological change in the study area, but fires probably cause important topsoil and nutrient depletion and may also affect water quality.     

面波群速度频散计算中滤波的数值实验研究

面波群速度计算中容易出现长周期部分时间域分辨率低的问题，因此，如何提高时间域的分辨率很重要。本文将引入等误差滤波的方法就改进群速度计算中滤波效果进行数值试验。结果表明，采用等误差滤波能明显提高群速度长周期部分的分辨率，对准确地测定长周期部分的群速度有重要意义。     

The BEAM-project: prediction and assessment of mixture toxicities in the aquatic environment

Freshwater and marine ecosystems are exposed to various multi-component mixtures of pollutants. Nevertheless, most ecotoxicological research and chemicals regulation focus on hazard and exposure assessment of individual substances only, the problem of chemical mixtures in the environment is ignored to a large extent. In contrast, the assessment of combination effects has a long tradition in pharmacology, where mixtures of chemicals are specifically designed to develop new products, e.g. human and veterinary drugs or agricultural and non-agricultural pesticides. In this area, two concepts are frequently used and are thought to describe fundamental relationships between single substance and mixture effects: Independent Action (Response Addition) and Concentration Addition. The question, to what extent these concepts may also be applied in an ecotoxicological and regulatory context may be considered a research topic of major importance, as the concepts would allow to make use of already existing single substance toxicity data for the predictive assessment of mixture toxicities. Two critical knowledge gaps are identified: (a) There is a lack of environmental realism, as a huge part of our current knowledge about the applicability of the concepts is restricted to artificial situations with respect to mixture composition or biological effect assessment. (b) The knowledge on what exactly is needed for using the concepts as tools for the predictive mixture toxicity assessment is insufficient. Both gaps seriously hamper the necessary, scientifically sound consideration of mixture toxicities in a regulatory context.In this paper, the two concepts will be briefly introduced, the necessity of considering the toxicities of chemical mixtures in the environment will be demonstrated and the applicability of Independent Action and Concentration Addition as tools for the prediction and assessment of mixture toxicities will be discussed. An overview of the specific aims and approaches of the BEAM project to fill in the identified knowledge gaps is given and first results are outlined.     

A Simplified Analytical Procedure for the Determination of Organically Bound Halogens in Salt‐containing Water Samples

A method was developed for the determination of organic halogens in water samples with the aim of minimizing matrix effects and simplifying the sample preparation technique commonly used. The method is based on the adsorption of organic halogens in modified hydrophilic divinylbenzene polymer columns and their elution with methanol. The adsorbent used enables rapid adsorption and desorption due to comparatively high operating flow rates and minimized solvent amounts. Furthermore, no additional reconcentration steps are needed. The methanol extract obtained is combusted with a standard EOX (extractable organic halogen) analyzer and the concentration of organically bound halogens is determined by microcoulometric analysis. The matrix effects are considerably reduced compared to the standard procedure (EN 1485) commonly used. A detection limit of 13 μg/L was established.     

西南三江地区矿产资源遥感综合预测方法

详细阐述了矿产资源遥感综合预测方法的工作程序、控矿要素的数字化分析与遥感找矿模型的建立,以及遥感矿产的综合分析评价方法与应用等,并以西南三江中段遥感综合预测成果佐证了矿产资源遥感综合预测方法在矿产资源预测中能使野外调查工作更具预见性和目的性,从而大大缩短了矿产资源调查的工作周期。