Microbially Mediated Redox Cycling at the Oxic–Anoxic Boundary in Sediments: Comparison of Animal and Plants Habitats

Microorganisms are responsible for the bulk of transformations that occur in surficial sediments. They are most active at redox boundaries where they can benefit from access to various oxidants and reductants generated during redox cycling events. To illustrate the dynamics of microbially mediated processes, especially those involving sulfur and metal cycles, processes were compared in habitats either bioturbated by a capitellid worm or inhabited by a salt marsh grass. The presence of macrofauna and macroflora greatly altered the three-dimensional array of redox gradients in sediments, but the type and form of reductants and oxidants provided varied greatly; clastic sedimentary infauna subducted solid phase organic material and iron oxides, whereas plant roots released dissolved organic matter and oxygen. These differences resulted in a bioturbated system that exhibited a rapid sulfur cycle (residence time of minutes), but a slower iron cycle (days), whereas vegetation caused a slow sulfur cycle and rapid iron cycle. Alteration of sediments by higher life forms also greatly affected the composition and relative abundances of sedimentary bacteria, even on short time scales. Although redox cycling at interfaces can be somewhat predictable, variations in response to biological and physical perturbations demonstrated wide differences in the dynamics of redox-mediated processes.     

Dissolved Oxygen and Nutrient Fluxes Across the Sediment–Water Interface of the Neckar River,Germany: In Situ Measurements and Simulations

A benthic in situ flume and a 1D biogeochemical sediment model to evaluate solute fluxes across the sediment–water interface have been developed. The flume was successfully used to determine oxygen and nutrient fluxes at various locations of the Neckar River in Germany. The experimental results were linked with vertical pore water concentration profiles and independently verified with the model. By combining experimental and model results we assessed the influence of dissolved oxygen concentrations in the water column and the availability of degradable organic matter on sediment oxygen demand. The results and the derived relations can be used to parameterize the sediment module of large scale water quality models, allowing one to assess the influence of sediment–water interactions on various aspects of river water quality. Moreover, the biogeochemical sediment model can help to improve the general understanding of the processes governing solute concentrations and fluxes in sediments and across their interfaces.     

巨灾债券与政府灾害救助

发生概率小而损失巨大的巨灾无疑对国民经济有着重要的影响。我国幅员辽阔，尽管每年灾害的性质和发生地点不同，但是损失总量和政府救灾的支付总量却是一个稳定的大数，然而依然不能满足救灾与恢复生产的需要。借鉴经济发达国家保险业的巨灾债券，首次提出在政府救灾中引入市场机制——发行政府巨灾债券。这对于投资者是收益高的风险投资，对于政府可以减轻公共财政负担，而对于受灾地区则可以获得更多的资金支援，加快恢复生产，保证经济增长的稳定性。     

国家地震紧急救援训练基地可控地震废墟设计(Ⅰ)--结构地震破坏模式

我国是一个地震多发的国家，地震灾害给我国造成了巨大的经济损失和严重的生命伤亡。专业化的震后紧急搜索救援能够最大限度地减少人民生命财产的损失，是防震减灾体系不可或缺的组成部分。通过大量的地震灾害实例，并借鉴地震灾害评估方法和建筑物抗震设计，对危害人类生命财产的建筑物震害的特征按照结构类型进行了详细说明，通过对这些地震中常见震害的了解和认识，为国家地震紧急救援训练基地的规划设计和相应搜索救援训练科目的设置提供依据。     

大庆油田分布式防震减灾信息和辅助决策系统——系统框架研究

简要论述了国内外防震减灾信息和辅助决策系统的发展状况。以大庆油田防震减灾信息和辅助决策系统为基础，详细探讨了分布式防震减灾系统的框架研究，包括ArcIMS的应用、系统框架的二次开发、数据库的远程连接和调用和系统框架的集成等。同时阐述了分布式网络GIS已经成为防震减灾信息和辅助决策系统建设的一个重要发展方向和它的应用价值。     

Environmental concern, attitude toward frugality, and ease of behavior as determinants of pro-environmental behavior intentions

This study investigates relations between environmental concern, attitude toward frugality, perceived ease of behavior, and stated intentions to engage in four different types of pro-environmental behavior, i.e., reductions in electricity and gas use, garbage, and automobile use, using data from 341 Japanese respondents. Environmental concern, attitude toward frugality and perceived ease of implementation were considered possible determinants. A structural equation analysis indicated that perceived ease of implementation had effects for all of the pro-environmental behaviors. It also indicated that environmental concern had a positive effect solely for garbage reduction, while attitude toward frugality had positive effects for gas and electricity reduction. For automobile use reduction, neither environmental concern nor attitude toward frugality had significant effects. The relationship between attitude toward frugality and mottainai, that is a Japanese concept indicating respect for resources, is then discussed, and it is suggested that educating people to have not only a high level of environmental concern but also a positive attitude toward frugality would be an effective means of promoting pro-environmental behavior.     

WILLINGNESS TO PAY FOR FLOOD RISK REDUCTION AND ITS DETERMINANTS IN JAPAN1

ABSTRACT: This study aimed to clarify public preferences for flood control measures in Japan, willingness to pay (WTP), and the main factors involved in WTP by applying the contingent valuation method. Findings showed that most residents surveyed expected some flood control measures, and revealed a diversity of interest in river management. WTP levels for different measures ranged from a mean of ¥2,887 to ¥4,861 and from a median of ¥1,000 to ¥2,000. However, WTP for additional flood risk reduction beyond initial levels was found to be zero. This was considered to be because WTP for flood risk reduction must be determined within a multi‐risk context. WTP for flood control measures may increase with per capita income, individual preparedness, and/or experience with flooding, but may decrease with distance from a river, acceptability of flood risk, and provision of environmental information. Furthermore, perception of flood risk may increase WTP, while perception of other risks may decrease it. Methods of dealing with environmental risk that were proposed in the survey may have affected WTP levels.     

基于计算机网络技术的天津市防震减灾技术系统

随着计算机的普及和网络技术的不断成熟,建立以计算机网络为依托的防震减灾地震快速响应系统已成为可能。“九五”期间,天津市地震局就计算机网络技术在防震减灾技术系统建设中的应用方面进行了尝试。通过计算机通信网络的建立,将地震监测预报、震后快速速报、早期趋势判定等工作环节有机地联系起来,在实际中发挥了重要作用。     

泥石流的运动机理和减阻

野外调查研究发现,存在着两种具有不同动力学特征和机理的泥石流,粘滞性泥石流和两相泥石流,粘滞性泥石流由卵石、沙和粘土构成,难以区分固相和液相,为典型的非牛顿体,具有间歇性流动,“铺床现象”,高达60％的减阻和显著超高等流动特点,粘滞性泥石流的阻力远小于流变参数所代表的阻力,传统的利用本构方程研究阻力的方法不能解决问题,研究表明,其30％的减阻是由于铺床作用,另外20％－30％,是由于流动混合物充气所致,两相泥石流主要由粗颗粒物质构成,两相之间有明显的相对流动,显示较大的阻力和发生“石街”现象。粘滞性泥石流沟谷的中值坡度为0．16,两相泥石流阻力大,因而河谷的平均坡度较大（0．19－0．27）。