石墨烯的环境行为及其对环境中污染物迁移归趋的影响

石墨烯是当前研究最热的碳纳米材料,具有独特的理化特性,在各领域具有广阔的应用前景.随着其生产和使用量的不断增大,石墨烯不可避免地会进入到环境中,从而给生态环境和人类健康带来风险.深入理解石墨烯在环境中的行为和归趋,探讨石墨烯对污染物环境行为的影响,对于科学客观评价石墨烯的环境风险具有十分重要的意义.本文对石墨烯的环境行为及其对污染物迁移归趋的影响进行了综述,主要介绍了石墨烯在水环境中的胶体特性和稳定性,以及在多孔介质中的迁移,重点探讨了石墨烯与重金属和有机物之间的相互作用,并从吸附机理、石墨烯与土壤组分之间的相互作用、石墨烯对污染物在环境中迁移及生物有效性的影响、石墨烯的定量方法等方面对该研究领域的前景和重点进行了展望,以期为该领域的深入研究提供借鉴并拓展新的思路.     

金属型纳米颗粒对植物的生态毒理效应研究进展

纳米技术的高速发展和人工纳米颗粒(NPs)的广泛应用带来的潜在环境风险已经引起国内外的广泛关注.金属型纳米颗粒(MB NPs)具有金属毒性和纳米毒性的双重效应,其生物毒性和生态风险已成为纳米毒理学的研究热点之一.植物作为生态系统中的重要组分,是NPs生物累积并进入食物链的潜在途径.本文论述了MB NPs在植物中的吸收、转运和累积过程,总结了MB NPs对植物的毒性效应及其机制,探讨了MB NPs植物毒性的影响因素,综合评述了近年来关于MB NPs对植物特别是农作物的生态毒理效应的研究进展,同时分析了目前研究中存在的问题,对今后的研究方向进行了展望.     

红树林湿地多环芳烃污染研究进展

多环芳烃（PAHs）是一类广泛存在于天然环境中的有机污染物,对生态环境和人类健康造成严重的潜在威胁。本文概述了红树林湿地中多环芳烃的来源和分布,其对红树植物的生理毒性效应、红树植物的生物修复作用和生物降解等方面的最新研究进展进行了总结,并对未来PAHs在红树林的研究趋势进行了展望分析。     

石墨烯健康风险研究现状及展望

石墨烯是一种新型的二维碳纳米材料,由于具有优异的电子、光学、机械等特性,已经被广泛应用于电子器件、复合材料、能源储存等领域.近年来,石墨烯在生物医药领域崭露头角,其在诸如生物传感器、细胞成像、药物输运、抗菌材料等方面的广泛应用,为生物医药技术带来了突破,也为人体健康带来了福音.然而,随着石墨烯以不同途径进入人们的生活,其对人体及其他生物体的安全构成潜在威胁,引发的健康风险正受到广泛关注.本文从石墨烯对生物体的影响及其同生物体的相互作用方面入手,综述了近年来石墨烯健康风险的研究进展,并且总结归纳了人体抵御石墨烯健康风险的途径及机制,最后指出了未来石墨烯健康风险方面的研究方向.     

水环境中药物和个人护理品(PPCPs)的污染现状及对藻类的毒性研究进展

药物和个人护理品(PPCPs)因持续排放到水环境且对水生态环境和人类健康造成潜在威胁而受到广泛关注.藻类作为水体重要的初级生产者,对水体的生态平衡和稳定起着重要的作用.本文围绕地表水PPCPs污染,介绍了不同国家和地区地表水体中PPCPs的浓度分布和污染特征,并从毒性效应、生物累积及潜在的生态风险等方面,综述了PPCPs对藻类的污染生态学研究进展,阐述PPCPs对藻类的毒性效应及机制,PPCPs在藻类中的生物累积,以及地表水体PPCPs的生态风险,为地表水体PPCPs的相关标准制定和修订,以及水体生态环境健康风险评价提供参考.     

土壤污染生态毒性效应评价研究进展

随着社会经济的高度发展,人类活动加剧,我国土壤污染问题突出,不仅威胁人体健康,同时也严重威胁动植物及微生物的安全,生态安全问题不容忽视。但是我国土壤污染风险管控目前主要关注人体健康,对生态系统的关注较少,缺乏土壤污染生态风险评估技术指南及基于生态风险的土壤环境质量基准及标准。准确评价土壤污染生态毒性效应,是制定土壤环境质量标准、实现生态风险评估及预警与管控的重要基础。针对土壤污染生态毒性效应评价问题,分别对土壤污染生态毒性效应特征、评价方法、评价终点、暴露-效应关系构建、生态毒性效应外推,以及群落水平与复合污染生态毒性效应评价等方面的关键问题展开了讨论,指出目前土壤污染生态毒性效应评价主要是基于单物种的急性毒性测试,利用个体和亚个体水平的指示物作为评价终点,缺乏针对群落及生态系统高水平评价终点的生态毒性效应评价方法,定量评价污染物尤其是复合污染物对土壤生物群落及生态系统的影响,是土壤污染生态毒性效应评价的关键问题和难点问题。建议今后重点开展以下3方面的工作1)群落及生态系统水平评价终点的筛选;2)土壤污染生态毒性效应环境影响因子识别及影响机制研究;3)土壤复合污染联合毒性效应定量评价及...     

重金属对植物种子萌发胁迫及缓解的机制

重金属元素一般为植物生长的非必需元素,具有较强的毒性,极易被植物吸收积累,降解困难,且能通过食物链危害人类健康。综述了近年来重金属对植物种子萌发过程中形态学指标、生理生化指标以及分子水平上的影响,主要包括重金属对植物种子萌发、幼苗生长、淀粉酶酯酶等水解酶活性、抗氧化酶活性、可溶性糖与脯氨酸含量及在细胞遗传毒性效应和蛋白基因表达水平上的影响,并总结了缓解植物重金属毒害的方法及治理措施,探讨了目前该领域研究中存在的问题,以及治理植物重金属毒害的研究方向,旨在为重金属污染研究与治理工作提供参考。     

外来植物的入侵机制及其生态风险评价

外来植物入侵已成为严重威胁生态系统健康发展的全球性问题,预防优于治理,对外来植物进行生态风险评价可有效地防御和降低入侵风险。本文基于生态风险评价理论,通过对外来植物入侵特性和过程的分析,探讨了外来植物入侵生态风险的评价方法。将评价程序分为风险源分析、风险受体评价、暴露与危害评价、风险综合评价和风险管理对策5部分,初步建立了风险源评价指标体系,以及度量生态损失和生态风险的指标和公式,进而得出外来植物入侵综合生态风险评价的方法。     

河流岸带湿地沉积物重金属分布对植被物种多样性和底栖动物群落特征的影响

河流岸带湿地栖息地完整性对河流水环境、水生态和水文的安全与健康具有重要意义,为探究河流岸带湿地表层沉积物重金属分布特征及其对植被和底栖动物的影响,对滦河干流上中下游河段表层沉积物、植物群落和底栖动物调查分析,采用生物毒性效应系数法和综合潜在生态风险指数法评价沉积物重金属污染特征,采用植被物种多样性指数和底栖动物完整性指数评价滦河植物和底栖动物群落特征,探究岸带湿地沉积物重金属空间分布与植被及底栖动物群落特征之间关系。结果表明,滦河表层沉积物总体呈清洁水平,但不同河段重金属空间分布差异较大,下游重金属生态危害系数和潜在生态风险指数高于上中游。湿地物种调查共识别维管束植物219种,大型无脊椎底栖动物105种,综合评价结果表明下游植物群落物种多样性和底栖动物群落完整性低于上中游。滦河下游岸带湿地沉积物重金属对生物群落具有生物毒性和潜在的生态风险,降低了植被物种多样性和底栖动物群落完整性。大型底栖动物完整性指数能够综合反映底栖动物群落结构特征变化,对河岸带湿地生态健康评价和监测具有重要意义。     

吲哚——种间及跨界信号分子新成员

吲哚作为一种典型的氮杂环芳烃化合物,在自然界中广泛存在。近年来,越来越多的研究表明吲哚具有一定的生物活性,是一种新型种间及跨界的信号分子。研究发现,吲哚不仅可以调节微生物的毒性、耐药性、生物膜形成以及群感效应等生理生化行为,调控植物生长发育和防御系统的形成过程,还能够影响动物的肠道炎症、细胞氧化压力及荷尔蒙分泌等生理健康。因此吲哚在微生物代谢、动物健康和植物生长等多个方面扮演了重要角色,具有重要的生物学及生态学双重意义。文中综述了吲哚从生物代谢到信号传递的研究历史,及其在微生物种内或种间以及微生物-动植物之间跨界的信号传导与调控作用的研究进展,旨在为揭示复杂环境中吲哚生物代谢及信号调控的生物学意义与生态学机制提供重要的理论指导。     

Review of Potential Environmental and Health Risks of the Nanomaterial Graphene

Several future applications have been suggested for the nanomaterial graphene, and its production is increasing dramatically. This study is a review of risk-related information on graphene with the purpose of outlining potential environmental and health risks and guide future risk-related research. Available information is presented regarding emissions, environmental fate, and toxicity of graphene. The results from this study indicate that graphene could exert a considerable toxicity and that considerable emission of graphene from electronic devices and composites are possible in the future. It is also suggested that graphene is both persistent and hydrophobic. Although these results indicate that graphene may cause adverse environmental and health effects, the results foremost show that there are many risk-related knowledge gaps to be filled and that the emissions of graphene, the fate of graphene in the environment, and the toxicity of graphene should be further studied.     

Effect of Graphene on the Sunlight Absorption Rate of Silicon Thin Film Solar Cells

The electromagnetic property of graphene is studied by finite-difference time-domain (FDTD) method. As the graphene has excellent electrical conductivity and high transparency, it has certain advantages as a transparent electrode for solar cells. This paper designs a three-layer film structure composed of graphene, silicon, and silicon dioxide (SiO₂). Then, the effects of the chemical potential and the scattering rate of the graphene on the light absorption of the film are studied. The study found that the electromagnetic property of graphene is relatively stable, which is not easily influenced by the external environment. After changing its chemical potential, scattering rate, and other parameters, it is found that the film absorption rate is less affected unless the large range of chemical potential changes; it will lead to a decline in the absorption rate of light.

     

Will transgenic plants adversely affect the environment?

Transgenic insecticidal plants based onBacillus thuringiensis (Bt) endotoxins, on proteinase inhibitors and on lectins, and transgenic herbicide tolerant plants are widely used in modern agriculture. The results of the studies on likelihood and non-likelihood of adverse effects of transgenic plants on the environment including: (i) effects on nontarget species; (ii) invasiveness; (iii) potential for transgenes to ‘escape’ into the environment by horizontal gene transfer; and (iv) adverse effects on soil biota are reviewed. In general, it seems that large-scale implementation of transgenic insecticidal and herbicide tolerant plants do not display considerable negative effects on the environments and, moreover, at least some transgenic plants can improve the corresponding environments and human health because their production considerably reduces the load of chemical insecticides and herbicides.     

Multicellular behaviour and production of a wide variety of toxic substances support usage of Bacillus subtilis as a powerful biocontrol agent

Intensive cultivation of plants in the monoculture field system in order to feed the continuously growing human population creates a need for their protection from the variety of natural competitors such as: bacteria, fungi, insects as well as other plants. The increase in the use of chemical substances in the 20th century has brought many effective solutions for the agriculture. However, it was extremely difficult to obtain a substance, which would be directed solely against a specific plant pathogen and would not be harmful for the environment. In the late 1900's scientists began trying to use natural antagonisms between resident soil organism to protect plants. This phenomenon was named biocontrol. Biological control of plants by microorganisms is a very promising alternative to an extended use of pesticides, which are often expensive and accumulate in plants or soil, having adverse effects on humans. Nonpathogenic soil bacteria living in association with roots of higher plants enhance their adaptive potential and, moreover, they can be beneficial for their growth. Here, we present the current status of the use of Bacillus subtilis in biocontrol. This prevalent inhabitant of soil is widely recognized as a powerful biocontrol agent. Naturally present in the immediate vicinity of plant roots, B. subtilis is able to maintain stable contact with higher plants and promote their growth. In addition, due to its broad host range, its ability to form endospores and produce different biologically active compounds with a broad spectrum of activity, B. subtilis as well as other Bacilli are potentially useful as biocontrol agents.     

湿地植物的丛枝菌根（AM）

随着对湿地重要性认识的增加,湿地植物的丛枝菌根（arbuscular mycorrhiza,AM）结构研究受到了关注。研究表明,AM结构在多种湿地类型和湿地植被类型中存在,但AM形成受植被生长地水文状况的影响;从湿地植物上的AM真菌种类看,球囊霉属（Glomus）是湿地环境的常有属。同陆生植物相比,有关湿地植物AM结构的研究尽管已取得了一些进展,但还有很大差距,尤其在我国还几乎处于空白状态。鉴此,从形成AM的湿地植被类型、湿地环境中的AM真菌种类、AM对湿地植物生长的影响,以及影响湿地植物AM形成的因素等方面进行了详细阐述,并对今后的研究方向做了展望,以期为我国开展湿地植物AM结构研究提供参考。     

Plant growth forms: an ecological and evolutionary perspective

Trees, shrubs, lianas and herbs have widely different mechanical architectures, which can also vary phenotypically with the environment. This review investigates how environmental effects, particularly mechanical perturbation, can influence biomechanical development in self-supporting and climbing growth forms. The bifacial vascular cambium is discussed in terms of its significance to growth form variation, ecology and evolution among extant plants, and during its appearance and early evolution. A key aspect of this developmental innovation concerned its potential for architectural and mechanical variation in response to environmental effects as well as optimizing hydraulic supply before the appearance of laminate leaves. Growth form diversity and its importance to past and present ecosystems are discussed in relation to both evolutionary constraints and ecological factors such as climatic change and atmospheric CO2 concentrations. We discuss how widely ranging growth forms such as climbers show a large range of developmental and phenotypic variation that has much to offer in understanding how the environment can modify plant development, particularly in terms of the bifacial vascular cambium. The broad approach we propose would benefit a wide range of studies from research into wood development to long-term ecological censuses of today's potentially changing ecosystems.     

Isolation of Two Plasticizers,Bis(2-ethylhexyl) Terephthalate and Bis(2-ethylhexyl) Phthalate,from Capparis spinosa L. Leaves

Many plants have been known to be contaminated and accumulate plasticizers from the environment, including water sources, soil, and atmosphere. Plasticizers are used to confer elasticity and flexibility to various fiber and plastic products. Consumption of plasticizers can lead to many adverse effects on human health, including reproductive and developmental toxicity, endocrine disruption, and cancer. Herein, we report for the first time that two plasticizers, bis(2-ethylhexyl) terephthalate (DEHT) and bis(2-ethylhexyl) phthalate (DEHP), have been isolated from the leaves of Capparis spinosa L. (the caper bush), a plant that is widely used in food seasonings and traditional medicine. 297 mg/kg of DEHT and 48 mg/kg of DEHP were isolated from dried and grounded C. spinosa L. leaves using column chromatography and semi-preparative high-performance liquid chromatography. Our study adds to the increase in the detection of plasticizers in our food and medicinal plants and to the alarming concern about their potential adverse effects on human health.     

Differential indirect effects of two plant viruses on an invasive and an indigenous whitefly vector: implications for competitive displacement

The role of vector–begomovirus–plant interactions in the widespread invasion by some members of the whitefly species complex Bemisia tabaci is poorly understood. The invasive B biotype of B. tabaci entered China in the late 1990s and had become the predominant or only biotype of the whitefly in many regions of the country by 2005–2006. Meanwhile epidemics of begomoviruses have been observed in many crops including tomato for which Tomato yellow leaf curl China virus (TYLCCNV) and Tomato yellow leaf curl virus (TYLCV) have been identified as two major disease-causing agents. Here, we conducted laboratory experiments to compare the performance of the invasive B and indigenous ZHJ1 whitefly biotypes on uninfected, TYLCCNV-infected and TYLCV-infected plants of tomato cv. Hezuo903, a cultivar that has been widely cultivated in many regions of China. The infection of tomato plants by either of the viruses had no or only marginal effects on the development, survival and fecundity of the B biotype. In contrast, survival and fecundity of the ZHJ1 biotype were significantly reduced on virus-infected plants compared to those on uninfected plants. Populations of the B biotype on uninfected and TYLCCNV-infected plants increased at similar rates, whereas population increase of the ZHJ1 biotype on TYLCCNV-infected plants was affected adversely. These asymmetric responses to virus infection of tomato plants between the B and ZHJ1 biotypes are likely to offer advantages to the B biotype in its invasion and displacement of the indigenous biotype.     

水生维管植物克隆繁殖方式的多样性

克隆繁殖是植物界的一种重要的繁殖方式 ,具有很大的多样性 ,特别是水生维管植物更是如此。通过对水生维管植物克隆繁殖方式的进行深入分析 ,不仅揭示了克隆繁殖在水生维管植物适应环境中的意义 ,而且也阐明了克隆繁殖方式作为水生维管植物的生存对策之一 ,在水生维管植物的生态和演化以及进化过程中的重要作用。