上地幔的性质

<正> 地表出现的每件事,包括如此多种多样的现象:山脉的造成、洋盆的形成、火山活动以及沉积作用的有规律的交替(伴随着动、植物种群的兴衰),都是发生在上地幔内部的事件的一种反应。地震波的速度对上地幔内部物质的密度有一定的影响;对大洋中喷出的火山岩的主要元素、微量元素及同位素化学进行的研究,可以得出上地幔的各部分的化学特征的间接     

环境决策支持系统的设计技术及发展趋势

简要论述了环境决策支持系统(EDSS)的发展历程,提出了EDSS开发技术的六大构成部分:应用平台的选择;系统的开发方式的选择;系统的开发工具的选择;系统的组成结构的建立;系统的基本功能的设计;系统的开放接口的设计。对系统设计的关键技术进行了分析,依据EDSS的应用现状,指出EDSS的发展趋势,对实际应用具有一定的指导意义和实用价值。     

序

<正> 人类继续在地球上的生存与发展遇到了严峻的挑战。人口的增长、矿产资源和化石燃料的逐步耗竭、土壤资源的侵蚀与退化、沙漠化的蔓延、地下水的枯竭、森林的破坏、酸雨的威胁、自然灾害的发生频度与严重性的增大、CO_2和温室气体的增加、大气臭氧层的变化、环境的污染、生态平衡脆弱性的增长和破坏……地球的生命支持系统面临崩溃的前景,地球的持续可居住性已成为全人类共同的忧虑。     

正确处理资源开发与生态保护的关系

这些年来,我国的经济在飞速提升,各行各业都取得了不错的发展。就我国多年的发展情况来看,在进行经济发展的时候就必定要对现有的资源进行开采,资源的开采必然会影响开采的地区的生态环境。可以说,资源开采促进着经济的发展,但是对于资源的开采需要掌握好一个度,过度的资源开采会严重的破坏当地的生态环境,为以后的生活和经济发展带来巨大的危害,甚至使得经济出现倒退的情况。正确的处理好资源开发和生态环境保护的关系是当前乃至以后经济发展的重中之重,合理的对现有的资源进行开发,在保证经济良好的发展的同时还可以对当地的生态环境起到一定的保护的作用,倘若因为资源过度开发导致当地的生态环境遭到破坏,可能会影响经济的发展,甚至出现使得经济倒退的情况。因为,正确处理资源开发与生态保护的关系就显得尤为重要了。本文主要对正确处理资源开发与生态保护的关系进行分析介绍。     

用您的绿色思维和行动构筑新世纪

永恒的爱波光粼粼的湖水是明亮的眼睛,宽阔的大海是我们的胸怀,清新的空气是我们的呼吸,绿色的大地代表我们永恒的爱。     

生活垃圾填埋场的现代化运营管理探究

随着社会的不断发展和人们生活水平的日益提高,生活垃圾的产量也是以惊人的速度在增多,并且,之前采用的简单填埋生活垃圾的做法造成了比较严重的环境污染,已经不能满足环境保护所做出的要求。本文主要着重突出城镇小型的生活垃圾填埋场所拥有的现代化的运营管理的具体情况,并通过生活中真实的案例来分析具体的运营策略及方法,希望对相类似的城镇的生活垃圾填埋场的管理有所帮助。     

空气污染对气候变化的影响与反馈

由于社会的不断的发展和科技的不断的提升,工业生产也得到了很大的发展,但是也正是由于工业的发展和人们不重视植被的保护,导致大量的污染物排放在空气中,从而导致了很严重的空气污染问题,并且现在的地方都出现的极端的天气,就目前的相关的调查来看,气候的变化和空气污染有很大的关系,基于此本文对于空气污染对气候变化的影响与反馈进行了相关的分析,希望可以通过下面的一些分析,让人们意识到空气对污染对于人类的生存环境的危害,从而增强人们的环境的保护意识,保护我们共同的地球家园。     

污水处理厂污水处理工艺改造设计研究

近年来,我国对于生态环境的治理工作十分的重视。在人们的日常生活中,污水是污染环境的一项十分严重的因素,所以加大对污水的治理的研究力度是当前我国环境保护的重要内容。下面我们针对目前普遍的污水处理工艺进行研究分析,然后分析研究出污水处理厂的污水处理工艺所存在的不足,然后针对存在的不足提出合理化的建议,有利于污水处理厂的污水处理工艺的升级换代,这对保护环境,提高人们的生活质量具有重要的价值。     

低功耗无线温湿度测量系统的设计开发研究

随着社会的发展,电气自动化技术的飞速发展,我国社会的工业有了较大的发展,单片机的使用在工业的发展中占据了重要的地位,不仅仅推动国家的进步和社会的经济发展,而且还推动我国重工业的发展,为我国社会的进步和发展做出突出贡献。本文针对凌阳公司的单片机16-SPE061A进行分析和讨论,设计研发一种低能耗的无线温湿度测量的系统,详细介绍了基站的设计和实现的过程。     

略论绿化意识在人类活动中的全方位渗透

随着人类环境意识的增强，绿化意识正向人类生活的各个领域渗透：政治经济的绿化－绿色和平组织的成立，农业生产的绿化－生态农业的兴起，工业的绿化－清洁生产的召唤，人类生活的绿化－绿色食品的发展，思维方式的绿化－绿色消费热潮方兴未艾。同时绿化意识的人类发出回归大自然、保持生态平衡的呼唤。     

Integrating mitigation and adaptation into climate and development policy: three research questions

The potential for developing synergies between climate change mitigation and adaptation has become a recent focus of both climate research and policy. Presumably the interest in synergies springs from the appeal of creating win–win situations by implementing a single climate policy option. However, institutional complexity, insufficient opportunities and uncertainty surrounding their efficiency and effectiveness present major challenges to the widespread development of synergies. There are also increasing calls for research to define the optimal mix of mitigation and adaptation. These calls are based on the misguided assumption that there is one single optimal mix of adaptation and mitigation options for all possible scenarios of climate and socio-economic change, notwithstanding uncertainty and irrespective of the diversity of values and preferences in society. In the face of current uncertainty, research is needed to provide guidance on how to develop a socially and economically justifiable mix of mitigation, adaptation and development policy, as well as on which elements would be part of such a mix. Moreover, research is needed to establish the conditions under which the process of mainstreaming can be most effective. Rather than actually developing and implementing specific mitigation and adaptation options, the objective of climate policy should be to facilitate such development and implementation as part of sectoral policies. Finally, analysis needs to focus on the optimal use and expected effectiveness of financial instruments, taking into account the mutual effects between these instruments on the one hand, and national and international sectoral investments and official development assistance on the other.     

Biochar: A review of its impact on pesticide behavior in soil environments and its potential applications

Biochar is produced from the pyrolysis of carbon-rich plant- and animal-residues under low oxygen and high temperature conditions and has been increasingly used for its positive role in soil compartmentalization through activities such as carbon sequestration and improving soil quality. Biochar is also considered a unique adsorbent due to its high specific surface area and highly carbonaceous nature. Therefore, soil amendments with small amounts of biochar could result in higher adsorption and, consequently, decrease the bioavailability of contaminants to microbial communities, plants, earthworms, and other organisms in the soil. However, the mechanisms affecting the environmental fate and behavior of organic contaminants, especially pesticides in biochar-amended soil, are not well understood. The purpose of this work is to review the role of biochar in primary processes, such as adsorption–desorption and leaching of pesticides. Biochar has demonstrable effects on the fate and effects of pesticides and has been shown to affect the degradation and bioavailability of pesticides for living organisms. Moreover, some key aspects of agricultural and environmental applications of biochar are highlighted.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

流动性视角下的国土空间安全及规划应对策略

人员、物资、能源资源等要素在不同层级空间的频繁流动,持续重构人类活动与自然环境关系,并对国土空间安全产生影响。从流动性视角进行国土空间安全探讨,提出在活动承载安全、资源与生态安全基础上,应考虑要素流动与人类活动、资源环境的耦合性及其潜在风险。流动性与国土空间安全的关系可以从“流”空间与场所空间耦合、“供—流—需”协调与资源配置安全、要素流与国土空间系统韧性三个方面来表征。以生态、水、粮食、经济、社会等安全塑造为目标,立足于各类要素流对人地关系系统影响的不确定性,以及自然灾害、突发公共安全事件等极端条件下的流动性风险,通过合理引导资源配置、科学布局国土空间要素等手段,实现人类活动、自然环境系统之间的自适应与良性反馈调节,形成安全韧性的国土空间格局与框架。在国土空间规划中,需要进行要素流与国土空间开发保护的耦合协调性分析评价,建立“形”与“流”结合的国土空间结构优化分析方法,增强不同空间的功能弹性以适应要素流动和活动集聚的不确定性,建立供需协同的国土空间支撑体系。研究对提升国土空间可持续发展水平以及保障人类生存安全具有重要意义。     

Alterations of organ histopathology and metallolhionein mRNA expression in silver barb, Puntius gonionotus during subchronic cadmium exposure

Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

污泥与煤混烧动力学及常规污染物排放分析

采用热重分析法研究了不同污泥掺烧比例及不同加热速率时污泥与煤的热失重特性.探讨了掺烧污泥对煤燃烧特性的影响,分析了掺入污泥对煤的燃烧变化规律,并进行了动力学分析.结果表明,加热速率增加时,样品的失重速率增大,开始失重温度及最终燃尽温度升高.掺烧时的TG曲线在400~600℃时有一个明显的失重阶段.失重速率峰值随着掺烧比的提高而升高,对应的温度降低.掺烧污泥后的混合样品的燃烧温度范围比单一燃煤时少20~100℃.非等温动力学模型分析可得,少量的污泥与煤掺烧时所需的活化能与煤较接近,对煤的正常燃烧影响不大.不同比例掺烧时产生的烟气中NOx、SO2、CO2生成量及减排规律因N、S、C含量不同而各有差异.热重分析及模型分析法可以为不同理化特性的煤与污泥掺烧提供初始理论依据.     

Contribution of additives Cu to its accumulation in pig feces： study in Beijing and Fuxin of China

Massive amounts of pig manure are produced by intensive pig farm in China, and the composition of pig manure has changed much due to the use of feed additives. However, little is known about the exact Cu （copper） feed as additives or present as contaminants in pig feed and the residues in feces. One hundred and thirty-seven feeds and one hundred and forty-two fecal samples from 48 pig farms were collected in Beijing and Fuxin cities in 1999 and 2005, respectively. The concentrations of Cu were in the range of 6.86-395.19 mg/kg in the feed samples, and the mean values were in the order of weaner〉 grower-finisher〉 sow＇s feeds. The high concentrations over EU recommendations implied that excessive levels of Cu are fed on many pig farms in Beijing and Fuxin. Cu was also present in high concentrations in feces, and concentrations were highly variable. Cu concentrations in the feces from grower-finisher and weaner pigs were significantly greater than feces of sows. The super-intensive and small-scale farms had higher levels of Cu in feces than the middle farms. Cu concentrations in pig feces were approximately 5-times greater than in pig feeds. Feed management in grower-finisher pigs on super-intensive and small-scale pig farms is needed to reduce high Cu concentrations in feces and risks to soil contamination while feces are land-applied.     

汽车排气尾流中微粒分布及其变化特性的研究

根据微粒核化、凝并及凝结模型对汽车排气尾流中微粒分布的变化特性进行了分析.结果表明,微粒的核化增加了排气尾流中超细微粒的数量;微粒的凝并和凝结将改变排气尾流中的微粒分布.在核化、凝并及凝结过程同时存在时,核化对微粒分布的影响相对较小,微粒分布的变化主要受凝并和凝结的作用.在排气管出口处,微粒的核化、凝并及凝结过程比较剧烈,微粒分布变化较大;随着距排气管出口距离的增加,微粒演变逐渐减弱.研究工作可以为汽车排放控制策略的确定以及汽车微粒对人体健康影响的研究提供依据.     

流域土壤基质与非点源磷污染物作用的3种模式及其环境意义

以华北地区典型农业流域为研究对象,针对流域不同空间分布和干扰程度下的土壤基质与污染径流中磷素的相互作用过程进行了模拟研究.研究发现,土壤基质与磷的作用过程呈3种模式,持留型、释放型及持留-释放转换型.持留型土壤基质对污染径流中磷酸盐具有较强的吸附作用,能有效持留径流中的磷素;释放型土壤基质则以解吸过程为主导,向径流中释放大量的磷素;持留-释放转换型土壤基质则呈动态性,当径流中磷酸盐含量较低时,解吸过程占优,以磷素释放为主,当径流中磷酸盐含量较高时,吸附过程占优,以磷素持留为主.结果表明,在自然环境及人类干扰的作用下,流域异质性景观下的土壤基质与非点源污染物的作用过程差异明显,其生态功能具有时空动态性.从非点源污染发生的角度来看,在空间上,土壤基质可成为污染物的汇或释放源;在时间上,同一区域存在源-汇功能的动态转化.因此,异质性景观中土壤基质与污染物作用过程动态机制的认识与判定,对于流域尺度上有效控制非点源污染十分关键.