大空间中庭内热分层环境下环境温度对烟气上升高度的影响

根据稳定线性热分层环境下羽流积分控制方程,分析了温度因素对羽流中性浮力点高度和羽流最大上升高度的影响,在大空间实验室开展了一系列实验,采集环境温度,计算竖向温度梯度,利用摄像机拍摄并记录烟气层上升高度,通过实验数据对理论分析结果进行了验证。     

不同氧化还原环境对煤矸石污染物质释放的影响

为评价不同氧化还原环境对煤矸石污染物质释放的影响,设置处理1(充氧饱和的曝气去离子水,Eh=229mV)、处理2(煮沸30min的去离子水,Eh=250mV)两种氧化环境及处理3(添加富含有机质的过滤养殖废水,Eh=14mV)一种还原环境的水溶液做浸提剂,对煤矸石进行0～9d的连续振荡浸提试验.结果表明:在浸提初期(0～1d内),煤矸石表面已形成的氧化产物迅速溶出,使得两种氧化环境和还原环境下的煤矸石浸出液pH都迅速降低,EC、Eh及多种溶出离子浓度迅速升高,但还原环境下煤矸石浸出液中Cu、F-浓度变化不显著,且还原环境下浸出液中其他离子虽有上升但显著低于氧化环境下.随浸提时间延长(1～9d),两种氧化环境下煤矸石浸出液pH继续降低,浸出液中Fe、Mn、Cu、Zn和SO2-4、F-多种污染物质溶出数量明显增加并呈现典型的持续氧化产酸过程;而还原环境下煤矸石浸出液的pH随时间延长降低不明显,Fe、Mn、Zn等污染物质溶出数量显著低于两种氧化环境下,Cu和SO2-4的释放也受到明显抑制.说明还原环境能有效抑制煤矸石氧化产酸及多种污染物质的溶出,且显著低于氧化环境.因此,在煤矸石堆场投加有机质形成还原(厌氧)环境可进行矸石污染的原位控制及治理.     

Sediment Quality Assessment in the Gulf of Gdańsk (Baltic Sea) Using Complementary Lines of Evidence

Sediments from Polish coastal environments were classified by a quality assessment approach that took into account trace metal and organic micropollutant concentrations, grain-size distribution, and organic carbon content. Generally, no benthic organisms were found at sites where sediments were classified as heavily polluted. However, areas characterized by a moderate contamination showed a variable composition of the benthic community and changing bioaccumulation patterns; therefore, no single species found in the Gulf of Gdańsk could be considered representative of the whole benthic environment. Although sediment monitoring must be considered a suitable tool to detect hot-spot pollution areas in coastal and inland waters, it should be complemented by bioaccumulation measurements to evaluate the actual risk posed by contaminants to benthic organisms. This “biological information” allows a better appreciation of the real benthic infaunal community exposure to chemicals and can usefully complement the existing sediment quality guidelines.     

实施环境-水文-生态-经济协同管理战略,保护和修复长江湖泊群生态环境

长江中下游浅水湖泊群具有十分重要的生态服务功能。然而,该湖群正面临江湖阻隔和富营养化等严重威胁。近年来,湖泊生态环境的保护和修复越来越受到重视,但治理效果不甚明显。其根本原因是:对由流域诸多胁迫导致的湖泊问题缺乏系统全面的认识,导致头痛医头、脚痛医脚。为此,本文提出应对长江湖群实施环境-水文-生态-经济协同管理战略,即在湖泊及其流域实施环境工程以控制入湖污染,实施生态水文工程以恢复自然水文体制,实施生态修复工程以增强生物自净能力,制定水环境经济制度以建立湖泊保护修复的激励和约束机制,构建生态健康评价体系以实施适应性管理,前提是责任主体明确。     

The Application of the Ecological Footprint: A case of passenger transport in Merseyside

The release of carbon dioxide from the burning of fossil fuels is believed to be responsible for climate change. In the UK, road transport emits 22% of the total output of carbon dioxide. This study applies the ecological footprint to Merseyside to ascertain the global environmental impact of passenger transport (expressed in hectares). Results show that car travel has a footprint of 704 000 hectares, which is 87% of the total footprint. It is demonstrated in scenarios that Policy initiatives involving the Local Transport Plan will cause the footprint to increase. It is also shown that individual behaviour could be influenced when highlighting the impacts of different modes of transport along the same route. By using the ecological footprint in educational programmes, the effect can be shown of carbon emissions and land appropriation on the 'school run'; these issues could be promoted alongside others such as health, safety, congestion, global equity and fairness.     

A Study of Annoyance Caused by Low-Frequency Noise During Mental Work

This article presents the results of an analysis of annoyance caused by low-frequency noise (including infrasonic noise) that occurs at work stations located in offices. The tests covered measurements of acoustic parameters specific for this type of noise and a survey conducted in the working environment and in laboratory conditions at a model of a work station.     

Tamarisk and river-channel management

Tamarisk (Tamarix chinensis, Lour.) an artificially introduced tree, has become a most common species in many riparian vegetation communities along the rivers of the western United States. On the Salt and Gila rivers of central Arizona, the plant first appeared in the early 1890s, and by 1940 it grew in dense thickets that posed serious flood-control problems by substantially reducing the capacities of major channels. Since 1940 its distribution and density in central Arizona have fluctuated in response to combined natural processes and human management. Groundwater levels, channel waters, floods, irrigation return waters, sewage effluent, and sedimentation behind retention and diversion works are major control mechanisms on the growth of tamarisk; on a regional scale of analysis, groundwater levels are the most significant under present conditions.     

茂兰喀斯特原生林不同地球化学环境的植物物种多样性

中国西南岩溶区是中国生物多样性分布中心之一。该区生态系统不断退化,生物多样性大量丧失,不同喀斯特地球化学背景下植被恢复的速度与成林性质存在明显差异。我们在最有代表性之一的贵州茂兰喀斯特森林保护区选取纯灰岩和纯白云岩两种岩性的喀斯特环境,对其元素地球化学特征及其中原生性植物群落的相异性和物种多样性进行了对比,结果发现:①不同岩性区域多样性:乔木层和灌木层为纯灰岩区>纯白云岩区,草本层为纯白云岩区>纯灰岩区,总体上纯灰岩区的高于纯白云岩区的;②各样地间的相似性系数都很低,相同岩性类型内的明显高于不同岩性类型之间的相似度;物种周转率高,且白云岩区高于石灰岩区,种类组成差异明显;③喀斯特区可溶岩地球化学背景通过喀斯特作用导致特殊的地形条件与元素地球化学特征,并引起局部小生境的分异从而影响植物群落特征。     

Soil loss as a measure of carrying capacity in recreation environments

This article describes three applications of the Universal Soil Loss Equation for further defining differences between natural environments in terms of their suitabilities for recreation use. Physical capacity limits based upon vulnerability to erosion and loss of soil productivity are discussed. Examples include: (a) applications to site planning and comparison of existing campsites; (b) use of the methodology for setting limits of acceptable change; and (c) characterization of third-order or larger watersheds that compare ecological land type interpretations with those based upon application of the equation.     

Trace elements in sediments in a city with agricultural development

The objective of this study was to determine the concentrations of trace elements in sediment samples taken from impermeable urban areas of a city with predominantly agroindustrial development characteristics. For this, samples were taken every month from paved streets in the city of Toledo, Paraná State (PR), Brazil. Thus, trace element levels were obtained through analysis performed by optical emission spectrometry with inductively coupled plasma. Levels of total organic carbon were also obtained through the dry combustion method. When compared to local background levels, the trace element levels were shown to be enriched in the following percentage proportions: barium (Ba) (45.4%), copper (Cu) (48.6%), chromium (Cr) (37.2%), manganese (Mn) (81.6%), nickel (Ni) (0%), lead (Pb) (40%), zinc (Zn) (283.7%), magnesium (Mg) (34.3%), and sodium (Na) (250.2%), whereas the carbon (C) percentages were around 1%. The most significant enrichment factors occurred for Ba, Cr, Pb, Zn, Mg, and Na. The highest rates occurred in geoaccumulation where the sediments were enriched by zinc. According to the principal guidelines, the concentrations obtained for cadmium (Cd), Cr, Cu, Ni, and Zn can cause adverse environmental impacts.