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.     

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。     

Environmental justice for the governance of aquatic environments

Environmental justice sheds light on the distributive and procedural aspects of planning and decision-making. We examined the challenges arising from the perspective of environmental justice on multi-level and participatory environmental governance by exploring the governance of aquatic environments in the Helsinki Metropolitan Area. We found three main challenges and potential responses to them. First, even though most of Helsinki’s shoreline is free and/or accessible by road and accordingly used actively by people for recreational purposes, many parts of the shoreline are perceived as inaccessible, reflecting a need to combine factual and perceived accessibility of aquatic environments in detail during the planning processes and to discuss reasons for possible discrepancies between these two. Second, there was a remarkable seasonal variation in the use of aquatic environments, so more attention should be paid to social-demographic factors explaining the distribution of the use of urban nature. Third, it seems to be difficult to capture the variety of perceptions of people and to integrate them into planning and decision-making processes even on a local scale, and this challenge is likely even more pronounced on higher levels of planning and governance. Thus, better integration of regional and local-scale planning procedures should be encouraged. Building on these observations, we conclude that integration of procedural and distributive environmental justice into the practices of the governance of aquatic environments could remarkably decrease unwanted trade-offs and potential conflicts in their use and management.     

有机污染物多介质环境的稳态非平衡模型

在稳态平衡模型的基础上，研究了有机污染物在多介质环境的稳态非平衡模型，并针对ＤＤＴ、１，２，４，－ＴＣＢ、ＨＣＢ、ＰＣＢ和ＤＭＰ５种化合物进行了计算。结果表明，该模型只须通过污染物在水中的浓度以及该化合物的各种物理化学性质和环境参数就可计算环境各相中污染物的浓度、逸度和质量分布，从而预测污染物在多介质环境中的归趋。     

莱州湾盐度变化现状及其对海洋环境与生态的影响

依据莱州湾生态监控区2004年5、8月份两个航次的盐度监测资料,结合近40a污染监测网莱州湾海域的监测资料和历年黄河入海径流量等有关资料,研究分析了近年莱州湾盐度变化状况及主要影响因素。研究发现近40 a莱州湾盐度变化趋势总体上呈上升态势,莱州湾盐度值与以前相比有明显升高。黄河径流量锐减和断流是引起莱州湾盐度升高的主要原因。莱州湾盐度升高,对莱州湾海洋生态环境的影响是多方面的,对湾内产卵场、育幼场和海洋生物群落结构都有一定的影响。     

前沟藻(Amphidinium hoefleri)和角刺藻(Chaetoceros gracilis)二甲基硫生产的实验研究

用实验室模拟的方法着重研究硅藻的角刺藻（Ｃｈａｅｔｏｃｅｒｏｓｇｒａｃｉｌｉｓ）和浮游甲藻的前沟藻（Ａｍｐｈｉｄｉｎｉｕｍｈｏｅｆｌｅｒｉ）生长过程中ＤＭＳ的生产及不同氮营养条件下对前沟藻ＤＭＳ生产的影响．结果表明：（１）前沟藻和角刺藻都可以生产二甲基硫（ＤＭＳ），但２者ＤＭＳ生产能力有很大差别，前沟藻ＤＭＳ平均生产率大约是角刺藻的１００倍．（２）不同生理阶段的ＤＭＳ产量不同．对数增长期的前沟藻细胞释放ＤＭＳ的能力最强，其ＤＭＳ速率是指数增长期的３倍．静止期和衰老期的前沟藻细胞ＤＭＳ的生产能力下降．（３）低氮条件对前沟藻细胞ＤＭＳ有促进作用．其中低浓度组（０．５ｍｇ／ＬＮａＮＯ３）ＤＭＳ产率是高浓度组（５０ｍｇ／Ｌ）的４倍．     

基于PSR的重庆市“一小时经济圈”生态环境评价研究

随着重庆市经济快速的发展,土地与生态环境的矛盾也越加尖锐。利用层次分析法,选择PSR（压力、状态、响应）指标模型对重庆市“一小时经济圈”2000和2006年的生态环境质量进行定量评价。结果发现：2000和2006年,整体上渝西地区的潼南、铜梁、大足、壁山、永川以及荣昌等区县生态环境都处于一个较差的水平,而涪陵均处于较高的水平。两年间研究区域生态质量均以优、良为主,所占面积比例分别为6096%和6256%;从2000年到2006年,研究区生态环境质量整体呈一个明显下降的趋势,显著变差的面积比例达到3171%,而显著变好的区域面积比例仅有524%;研究区生态环境下降区域面积比例达到5972%,而生态环境上升区域面积则仅有2702%,生态环境质量变化区域具有明显的空间差异性,显著变差区域基本分布于渝西南地区,即成渝交通干线辐射区域及主城大部分地区.     

Influence of thermally activated paper sludge on the behaviour of blended cements subjected to saline and non-saline environments

Background, aim and scope  One of the problems to affect Portland cement matrices is low resistance to aggressive agents, due principally to the presence of a high content of portlandite in the hydrated cements. Pozzolanic materials have played an important role in the improving the durability of cement-based materials for decades. This work studies the behaviour of cement mortar matrices blended with 10% calcined paper sludge (source for metakaolinite) and exposed to different environmental conditions (saline and non-saline environments) after 6 and 12 months of exposure. Materials and methods  Two cements were studied: an ordinary Portland cement (CEM 1, 42.5R), acting as reference cement, and a blended cement formulated by mixing 90% (by mass) of CEM 1, 42.5R with 10% (by mass) of paper sludge calcined at 700°C for 2 h. The specimens were exposed 1 year to saline and non-saline environments. All the mineralogy samples were studied through X-ray diffraction and scanning electron microscopy (SEM) equipped with an energy dispersive X-ray analyser. The in-depth study on ionic mobility was performed on samples subjected to natural exposure (coast and tableland) for 6 and 12 months. Results  Portland cement was composed of quartz, calcite, calcium hydroxide and tobermorite gels. The pozzolanic cement (10% calcined paper sludge) is of the same composition but a high calcite concentration and barium carbonate. SEM analysis from coastline show deposits of variable composition. The deposits are identified on the surface of different mineral components. The minerals from tableland are much fractured, i.e. calcite and feldspars. Inside the fractures, the deposits and the ions are located and trapped superficially. Discussion  SEM analysis of control cement Portland and 10% calcined paper sludge shows deposits on quartz and calcite with a very high concentration of Pb, Zn, Cl and barium sulphate. A very porous aspect is due to the presence of the different aggregate types. This porous configuration permits retention of the ion environment. The pozzolanic cement in environments subject to the saline mist favours the retention and transport of ions observed. Something similar also happens with the increase in exposure to outdoor weather. Non-saline samples show temperature changes (ice or thaw cycles). Barium retention is kept on the surface in fracture lines by the gelification processes. In general, it may be inferred that an increase in exposure time increases the diffusion of ions towards test piece interiors. The chemical composition profiles show that the ions present different penetration speeds. Conclusions  The results indicate the better vulnerability of pozzolanic cements from calcined paper sludge in saline and non-saline environments. The cements with a 10% addition of calcined paper sludge favour retention and transport of ion has been observed. Recommendations and perspectives  Today, projects are centred on a new recycling line for industrial waste of this kind, with special attention on its incorporation in cement manufacture as a pozzolanic material, setting the most appropriate activation conditions of the mineralogical compound in this waste (kaolinite and metakaolinite) and taking them as a starting point for this project. The use of pozzolanic cement with 10% addition of calcined paper sludge is a system which favours ionic retention.     

The psychological benefits of indoor plants: A critical review of the experimental literature

People have been bringing plants into residential and other indoor settings for centuries, but little is known about their psychological effects. In the present article, we critically review the experimental literature on the psychological benefits of indoor plants. We focus on benefits gained through passive interactions with indoor plants rather than on the effects of guided interactions with plants in horticultural therapy or the indirect effect of indoor plants as air purifiers or humidifiers. The reviewed experiments addressed a variety of outcomes, including emotional states, pain perception, creativity, task-performance, and indices of autonomic arousal. Some findings recur, such as enhanced pain management with plants present, but in general the results appear to be quite mixed. Sources of this heterogeneity include diversity in experimental manipulations, settings, samples, exposure durations, and measures. After addressing some overarching theoretical issues, we close with recommendations for further research with regard to experimental design, measurement, analysis, and reporting.     

The desirability of views of city skylines after dark

Three studies used digital color photographs to compare responses to natural scenes, skylines after dark, and skylines during the day (seven of each). Study 1 had 59 respondents rate the pleasantness of each scene. They gave similar ratings to Night Skylines and Natural Scenes, and rated each as more pleasant than the Day Skylines. Study 2 had 56 other participants choose from each of seven sets of each kind of scene the one they would most like to have as a framed print in their home or office, and to report the reasons. Participants chose Night Skylines most often, followed by Natural Scenes and then Day Skylines. While participants most often picked attractive as a reason for their choice, those who chose Night Skylines also picked exciting as the reason, and those who picked Natural Scenes also picked relaxing or peaceful as a reason. Study 3 obtained ratings of selected formal features of each scene. The 23 judges rated the Natural scenes as more natural, orderly, open, and curvilinear, less complex, and as having smoother transitions than either Day or Night Skylines; and they judged the Night Skylines as higher in complexity but lower in order than Day Skylines. The results suggest that preferences in relation to the scene categories may well depend on a mix of their formal characteristics and their content.