太湖湿地生态系统服务功能价值评估

随着生物资源价值估算方法的日益成熟,生态系统的服务评估成为生态系统研究的热点。运用市场价值、影子工程、碳税法等方法对太湖湿地生态系统的物质生产功能、环境调节功能和文化社会功能等直接与间接价值进行评估。结果表明：太湖湿地生态系统具有巨大和多重服务价值,总价值为112.39×10⁸元。其中,生态环境调节与维护功能价值最大,占总服务价值的48.98%;其次是物质生产与供给功能,占29.1%;文化社会功能最小,占21.91%。通过对9项子功能进行评估得出,调蓄洪水的功能价值最大,约占26.23%,供水功能其次,约占24.56%,气候调节功能,约占18.23%,科研教育价值约占13.16%,植被资源生产功能价值最小,约占0.09%。此项研究首次定量评估了太湖湿地生态系统的服务功能价值,研究成果对于认识太湖湿地的价值,有针对性地保护太湖湿地具有现实意义。     

The ecological effects of trichloroacetic acid in the environment

Trichloroacetic acid (TCAA) is a member of the family of compounds known as chloroacetic acids, which includes mono-, di- and trichloroacetic acid. The significant property these compounds share is that they are all phytotoxic. TCAA once was widely used as a potent herbicide. However, long after TCAA's use as a herbicide was discontinued, its presence is still detected in the environment in various compartments. Methods for quantifying TCAA in aqueous and solid samples are summarized. Concentrations in various environmental compartments are presented, with a discussion of the possible formation of TCAA through natural processes. Concentrations of TCAA found to be toxic to aquatic and terrestrial organisms in laboratory and field studies were compiled and used to estimate risk quotients for soil and surface waters. TCAA levels in most water bodies not directly affected by point sources appear to be well below toxicity levels for the most sensitive aquatic organisms. Given the phytotoxicity of TCAA, aquatic plants and phytoplankton would be the aquatic species to monitor for potential effects. Given the concentrations of TCAA measured in various soils, there appears to be a risk to terrestrial organisms. Soil uptake of TCAA by plants has been shown to be rapid. Also, combined uptake of TCAA from soil and directly from the atmosphere has been shown. Therefore, risk quotients derived from soil exposure may underestimate the risk TCAA poses to plants. Moreover, TCE and TCA have been shown to be taken up by plants and converted to TCAA, thus leading to an additional exposure route. Mono- and di-chloroacetic acids can co-occur with TCAA in the atmosphere and soil and are more phytotoxic than TCAA. The cumulative effects of TCAA and compounds with similar toxic effects found in air and soil must be considered in subsequent terrestrial ecosystem risk assessments.     

昆山市生态系统服务价值变化研究

在Constanza的生态系统服务价值理论的基础上,计算了1994－2002年昆山市生态系统服务价值的变化。建设用地对耕地和水域面积的占用,引起了昆山市的生态系统服务价值逐渐下降： 9年间生态系统服务价值（ESV）总量下降了8.9%,人均占有量（Ave(ESV)）下降了13.0%。各种土地利用方式的生态系统服务价值的弹性系数都小于1。水域面积的变化则对生态系统服务价值变化起到放大作用。耕地面积的变化主要是影响昆山市的粮食安全问题,而水域的变化则在更大程度上影响生态系统服务功能方面。     

东北农牧交错带典型区土地利用变化及其生态效应

东北农牧交错带是典型的生态环境脆弱区，具有敏感性强、退化趋势明显等生态脆弱性特征。本文利用1986、2002年两期TM/ETM影像，揭示了吉林西部16年来土地利用／覆被的时空变化规律，并依据Costanza R．等人对全球生态系统服务价值的评估方法。分析了土地利用变化对区域生态系统服务价值的影响。结果表明：16年来，吉林西部土地利用／覆被发生了剧烈变化。耕地、盐碱地面积大幅度增加，草地、水域和湿地的面积大幅度减少，区域生态系统服务功能出现明显的衰退。生态系统服务价值显著地减少。吉林西部生态系统服务价值由1986年的767．1亿元／a下降到2002年的624．1亿元／a，减少幅度达18．6％，年均递减速率达1．6％。16年来该区域生态环境恶化和以经济利益为目的的土地利用结构调整，给区域生态系统服务功能和可持续发展能力带来巨大负面影响。     

土地利用和生态系统服务功能变化研究——以三峡库区大宁河流域为例

将土地利用类型分类为耕地、有林地(森林地)、灌木林地、草地、迹地、水体、建设用地和未利用地8类.以遥感数据为数据源,通过自动分类和人工解译相结合的方法获取了以上土地利用类型,并对三峡库区大宁河流域的土地利用变化过程和驱动力做了分析.以Costanza等人的全球生态系统服务价值的估测结果为基础,对各种地类生态服务功能价值重新赋值,进而估算近30年大宁河流域的生态服务价值,分析了其变化过程.结果表明:近30年,大宁河流域土地利用总的变化趋势是林、灌、草地经历了不断破坏和缓慢恢复的过程,耕地面积经历了先增后减,建设用地不断扩展.经济发展、人口增长和国家政策是土地利用变化的主要原因.生态系统服务功能经历了一个先损害后恢复的过程,表现为生态服务价值从1973年到1995年不断减少,而1995年到2002年连续增加.     

Distribution and bioavailability of ceria nanoparticles in an aquatic ecosystem model

Along with the increasing utilization of engineered nanoparticles, there is a growing concern for the potential environmental and health effects of exposure to these newly designed materials. Understanding the behavior of nanoparticles in the environment is a basic need. The present study aims to investigate the distribution and fate of ceria nanoparticles in an aquatic system model which consists of sediments, water, hornworts, fish and snails, using a radiotracer technique. Concentrations of ceria in the samples at regular time intervals were measured. Ceria nanoparticles were readily removed from the water column and partitioned between different organisms. Both snail and fish have fast absorption and clearance abilities. Hornwort has the highest bioaccumulation factors. At the end of the experiment, sediments accumulated most of the nanoparticles with a recovery of 75.7 ± 27.3% of total ceria nanoparticles, suggesting that sediments are major sinks of ceria nanoparticles.     

职业卫生信息化网络平台研究

当前我国职业卫生监管工作存在薄弱环节、监管手段相对落后,难以满足我国职业病防治工作形势的需求。将信息化技术应用于职业卫生监管,可有效提高职业卫生监管工作的科学性和有效性。阐述了职业卫生信息化网络平台建设的必要性,提出了职业卫生信息化建设的整体框架,分析并论述了具体建设内容以及建设过程中应注意的几点问题。     

The many benefits of employee well‐being in organizational research

We undertake three objectives in this Incubator. We begin with a discussion of how well‐being has been considered in organizational research. Second, we provide an overview of the relationship between employee well‐being and such workplace outcomes as job performance, employee retention, and cardiovascular health. Third, we introduce exciting research directions. Copyright © 2012 John Wiley & Sons, Ltd.     

基于三角随机模拟和ArcGIS的河流水环境健康风险评价模型

基于河流水环境系统中随机性、模糊性等多种不确定性共存或交叉存在的特性,将三角模糊数与随机模拟方法相耦合,构建了三角随机模拟模型,并将其应用到湘江(长沙段)的健康风险评价中。通过将各参数浓度进行三角模糊化和随机模拟,结果表明,各断面污染物造成的健康风险的变化趋势,总体沿湘江上游至下游逐步降低,表现为昭山 > 猴子石 > 五一桥 > 橘子洲 > 乔口 > 三汊矶,且昭山、三汊矶断面和乔口断面均有恶化趋势。相对于常规的确定性方法,本模型能够得出评价区域健康风险的可能值区间及其相应的概率水平等定量信息,更加客观、全面地表征评价区域的风险状态及其空间分布差异,为决策者提供更多有用的信息。     

基于健康度分析的电网单元设备集可靠性评估研究

电网作为一类关键基础设施,能否安全稳定运行直接关系到社会的安全稳定以及经济发展。对电网进行可靠性评估,找到薄弱环节并给予增强稳固来提高电网整体抗扰性,降低电网风险,具有重要现实意义。在构建电网网络结构中节点单元的可靠性评估模型时,以设备可靠性模型为基础,将电网设备的健康度分析、老化度分析引入可靠性评估模型,一定程度上减少了可靠性评估模型中人为主观因素的影响;同时,将动态健康度预测和静态健康度总结进行综合,减少了各自评估的缺点,为可靠性评估提供了更为准确的变量信息,能够更为准确的区分不同设备的安全性程度。通过评估模型的构建和Q市电网算例的应用,表明该模型可以有效、快捷的衡量电网设备信息,为电网一线工作人员提供了较为方便的评估手段。