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1.
The novel coronavirus, SARS-CoV-2, which has caused millions of death globally is recognized to be unstable and recalcitrant in the environment, especially in the way it has been evolving to form new and highly transmissible variants. Of particular concerns are human-environment interactions and the handling and reusing the environmental materials, such as effluents, sludge, or biosolids laden with the SARS-CoV-2 without adequate treatments, thereby suggesting potential transmission and health risks. This study assesses the prevalence of SARS-CoV-2 RNA in effluents, sludge, and biosolids. Further, we evaluate the environmental, ecological, and health risks of reusing these environmental materials by wastewater/sludge workers and farmers. A systematic review of literature from the Scopus database resulted in a total of 21 articles (11 for effluents, 8 for sludge, and 2 for biosolids) that met the criteria for meta-analysis, which are then subdivided into 30 meta-analyzed studies. The prevalence of SAR-CoV-2 RNA in effluent and sludge based on random-effect models are 27.51 and 1012.25, respectively, with a 95% CI between 6.14 and 48.89 for the effluent, and 104.78 and 1019.71 for the sludge. However, the prevalence of SARS-CoV-2 RNA in the biosolids based on the fixed-effect model is 30.59, with a 95% CI between 10.10 and 51.08. The prevalence of SARS-CoV-2 RNA in environmental materials indicates the inefficiency in some of the treatment systems currently deployed to inactivate and remove the novel virus, which could be a potential health risk concern to vulnerable wastewater workers in particular, and the environmental and ecological issues for the population at large. This timely review portends the associated risks in handling and reusing environmental materials without proper and adequate treatments.  相似文献   

2.
The survival of Vibrio cholerae -the pathogen agent of cholera- in aquatic environments is linked to both abiotic and biotic ecological factors, which are likely to be influenced by global climate changes and the resulting rise in sea level. Yet little attention has been paid to the possible impacts of these predicted global environmental changes on water-borne diseases such as cholera. The probable ecological mechanisms to explain why cholera may increase if predicted global warming and sea level rise do occur have, as yet, not been addressed. The objective of this paper is to argue the hypothesis that the survival of Vibrio cholerae in aquatic environments may be favoured by global warming and flooding of low-lying coastal areas due to rising sea level. Those changes may enhance primary and secondary transmission of cholera in developing nations, particularly among populations settled in low-lying coastal areas of tropical regions. Primary transmission is also likely to increase in developed nations, mainly among populations living in low-lying coastal areas of subtropical and temperate regions, where new foci of hypoendemic cholera may appear. Nevertheless, if current high levels of hygienic standards in developed nations are relaxed, secondary transmission of cholera may also increase. The prediction and assessment of the potential impact of global climate change on cholera epidemic and endemic potential and its geographical distribution should consider the role of the aquatic reservoirs of Vibrio cholerae in the transmission and endemicity of cholera. The geographical distribution of cholera depends not only on social and cultural factors, but also on ecological variables. On the other hand, global climate changes may cause different impacts in different ecosystems and geographical landscapes. Hence it would be useful to calculate and map future cholera incidence rates for areas defined by natural boundaries, such as ecosystems and geographical landscapes, in search of space-time associations between cholera incidence rates and environmental changes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

3.
大气颗粒物,尤其是细颗粒物PM2.5,是有毒和有害物质的载体,对人体健康具有重要的影响,同时大气颗粒物具有吸湿性、光学吸收和散射能力以及云凝结核活性等,对环境和气候变化具有重要的作用,大气颗粒物进一步的长距离输送还会对区域和全球地球化学循环产生重要影响.总结了当前大气颗粒物的物理化学特征研究进展,分析了离线和在线分析技术在大气颗粒物主要组分检测中的应用,阐述了大气颗粒物源解析技术的应用现状,以及由于大气颗粒物污染对环境、气候、人体健康和地球化学循环等产生的影响,最后展望未来大气颗粒物研究的重点问题.   相似文献   

4.
刘世荣  孙振亚 《矿物学报》1995,15(3):276-280
本文利用EPMA和AEM对预先富集的碳质体中的微细粒金的赋存状态进行了研究,结果表明金均以偏小的高成色金胶粒被非晶态的碳质体吸附、包裹乃至碳质与之形成碳壳。由研究结果认为:①碳质中金可能析出于胶体凝聚作用;②应该注意有机质以机械方式搬运金粒的可能性;③碳质包裹金粒及在金粒表面形成碳壳是碳质体与金紧密结合的表现形式。  相似文献   

5.
生物地球化学循环是地球系统物质循环的核心,是维系地表生态系统稳定和人类社会可持续发展的重要基础。然而,气候变化以及人类的过度干扰可能会显著改变表层地球系统中的生物地球化学循环过程,尤其是脆弱的喀斯特生态系统。特殊的多孔隙关键带结构也加速了喀斯特地区物质循环及其对外界环境变化的响应,影响了不同尺度的物质循环和生物地球化学过程。本研究主要综述了宏观尺度(气候变化)、中尺度(人类活动)和微观尺度(微生物活动)的环境变化对喀斯特地区生物地球化学循环的影响。结果表明多要素变化导致喀斯特地区物质循环受到强烈影响,气候变化、人类活动和微生物活动及其耦合关系对喀斯特地区生物地球化学循环的调控作用具有重要意义。最后,本研究强调了现有研究的局限性并指出未来研究的挑战与方向,即未来应从系统研究(如地球关键带)的视角出发,将多尺度观测-分析与综合模型集成研究并举,从而构建多源多尺度耦合的过程和系统模型,进而为阐明喀斯特系统的演变规律和动力学机制、实现喀斯特地区的生态保护和高质量发展提供理论基础。   相似文献   

6.
Mudflats and associated mangroves are most important ecosystems of tropical coastal regions. Mangroves play a very important role in maintaining the environmental balance; thus in addition to mangrove reforestation and restoration, afforestation has also been practiced. We studied distribution of sediment components (sand, silt, clay) organic carbon (OC), heavy metals (Fe, Mn, Cu, Zn, Cr and Co) and pH in six cores collected from one of the largest mudflats of Mandovi estuary, west coast of India. The temporal distribution patterns of these proxies suggested that past changes in tidal energy conditions, fresh water inflow and anthropogenic activities over the last few decades, together helped in development of a middle tidal flat in this estuary. In cores collected from the mangroves, trapping and deposition of finer particles and organic matter were enhanced by a complex aerial mangrove root system in recent years. Mangroves were, therefore, suggested to enhance the buildup of mudflats in Mandovi estuary. Cores collected from mudflats also exhibited higher deposition of finer particles and organic matter (except MF2) in recent years, suggesting maturity and greater stability of the entire mudflat in recent years. Middle tidal flats (mudflats) of Mandovi estuary may, therefore, prove to be suitable substrates for mangrove proliferation in the near future. Finer sediments deposited mainly from mining activities in recent years exhibited lower pH and higher metal content. Organisms dwelling in these recently deposited sediments are, therefore, at higher risk of bioaccumulation and metal toxicity.  相似文献   

7.
现代冰川过程与全球环境气候演变   总被引:3,自引:0,他引:3  
文章从宏观和微观两个方面扼要阐述了现代冰川过程与全球变化之间的关系。南极冰盖和格陵兰冰盖冰川物质平衡值目前还没有确切结论,虽然它与全球海平面的升降密切相关。山地冰川末端进退变化和冰川物质平衡与全球升温对应较好。极地冰盖现代降水中的稳定同位素比率,主要阴、阳离子、生物有机酸、微粒、超痕量重金属元素、宇宙尘埃以及火山灰等杂质的含量,为认识地球现代环境气候状况提供了丰富的资料。极地冰盖冰芯的分析结果为重建过去气候环境提供了大信息量,高保真度和高分辨率的资料为预测未来气候环境奠定了坚实基础,具有其它任何载体无法取代的优越性。山地冰川的现代和过去气候环境记录,对研究全球和区域性气候环境状况与变迁意义重大  相似文献   

8.
The upper mantle, crust, hydrosphere and atmosphere of Earth are kept in a geophysical, geochemical and thermodynamical state far from astrophysical and planetary equilibrium. The system oscillates around a quasi-stable centre following laws governing dissipative or dynamic systems. The energy and materials necessary for such global pseudo-equilibria are fed in, stored and released on a geological time-scale by (a) the energy and electron channelling processes of photosynthesis, respiration and fermentation, (b) biologically controlled accumulation of energy and matter into crustal reservoirs and much later (c) release of the latter from crust and upper mantle into surface-related geotectonical and geochemical cycles. Phototrophic and chemorganotrophic bacterial microorganisms of microbial mats, potential stromatolites or microbialites are capable of anoxygenic and oxygenic photosynthesis, of aerobic and anaerobic respiration and of organic and inorganic fermentation, i.e. disproportioning of energy-rich molecules. In this way large amounts of photosynthate are transformed on a global scale into hydrocarbons and sulphides (sulphate serving as electron acceptor for anaerobic respiration or fermentation). Inorganic reduced compounds produced by the same processes of photosynthesis followed by respiration and fermentation are stored as sulphides of iron, lead, zinc, silver, gold etc. All the aforementioned microbial processes can transfer energies and matter at a global scale. Thus disparities of the Earth's crust and mantle from the geochemical equilibrium may not be caused solely by internal temperature, radioactivity and gravity gradients, but increasingly by life processes. The biogenic formation of energy-rich compounds on a global scale delivers huge amounts of energy and electrons to the crust, which are recycled through geological time. The quantities of energy involved appear in themselves to be sufficient to provide the driving force for geotectonic processes. Thus, a model of geophysiological equilibration of geochemical cycles and geotectonics is proposed in which the biota play the role of energy and matter transmitters for geodynamic processes. Living matter controls and transfers more than 10% of the Earth's mass in this system with turnover times of up to 500 million years. The transfer speed of each individual atom according to the model must have gradually decreased since the Precambrian, while the amounts of energy and matter stored and cycled have in turn increased, as also witnessed by the increase in the thickness of the crust. Earth as a bioplanet has come of age.  相似文献   

9.
气候环境变化的湖泊沉积学响应   总被引:24,自引:0,他引:24  
湖泊沉积可作为气候和环境变化的信息库,它能提供时间分辨率高达百年至十年的气候变化信息。湖泊沉积能灵敏地反映与地球轨道力变化相关的气候效应,以及在此背景上叠加的非线性气候事件。湖泊沉积与其中的古生物组合、元素同位素组成是古气候环境的重要替代指标,为检验大气动力学气候模型和进一步改进模型,预测未来气候提供了依据。  相似文献   

10.
不锈钢产业是镍最大的消费领域,对全球镍消费趋势起决定性作用.近年来,电动汽车产业逐渐发展,动力电池对镍需求也逐渐得到重视,该领域的镍消费普遍被认为是最具发展潜力的镍消费领域.本文通过对镍需求的历史和现状进行分析,对未来不锈钢及电动汽车领域等重要部门的镍需求进行了展望,认为未来镍需求将由2019年243万t增长至2030年445万t,其中不锈钢领域仍为其第一大消费领域,电池领域上升为第二大消费领域;通过梳理全球镍资源情况及供应开发情况,认为由于受到疫情冲击,2020年镍矿供需形势紧张状态将有所缓解,但随着未来疫情好转,未来几年内镍仍将处于供需紧张状态;此外,通过梳理镍供应链条,本文认为市场对硫酸镍以及硫化镍矿需求未来有望持续增长,这对镍盐价格将形成有力支撑,对推动全球红土镍矿湿法产能建设也将形成一定促进作用.  相似文献   

11.
12.
矿物细颗粒物和微生物个体都是大气颗粒物(PM)重要组成部分,它们在形态、共生关系和空气动力学行为上均有高关联度.本文对可吸入颗粒物(IP)和可吸入矿物细颗粒(IMG)的颗粒特性、自由基和生物活性、IP和IMG与微生物相互作用效果的研究现状做了阐述,指出大气颗粒物与微生物的相互作用的重要性.提出今后应重点研究可吸入矿物细颗粒物的环境化学与微生物作用行为,研究IMG-微生物体系近尺寸作用体系中的尺寸效应、界膜作用等对矿物颗粒物表面形态、表面电性、表面基团及自由基等的影响,分泌蛋白质与相变、元素变价、溶解(络合)的关系以及由此引起的颗粒物活性和生物毒性的变化等.  相似文献   

13.
环境沉积学的兴起   总被引:1,自引:0,他引:1  
鲜本忠  姜在兴 《沉积学报》2005,23(4):677-682
面对生态、环境、灾害、全球变化等重大问题和环境科学、沉积学的发展,环境沉积学应运而生。环境沉积学的发展经历了萌芽和兴起2个阶段,直至20世纪90年代中后期,其研究始得以广泛关注。在前人研究的基础上,初步厘定了环境沉积学的概念和研究目的,指出其研究内容既包括沉积学中的环境问题,又包括环境科学中的沉积问题,4个研究方向分别为原生环境沉积学、污染物环境沉积学、生态环境沉积学和全球变化环境沉积学。环境沉积学以环境和灾害研究为己任,将在解决人类面临的环境污染、生态破坏、地质灾害、全球气候变化等重大问题的研究中发挥越来越重要的作用,是未来沉积学发展的重要方向之一。  相似文献   

14.
We monitored near-surface atmospheric fallout (15-cm above ground) and soil solution (at 15, 35 and 55 cm below ground) derived nanoparticles over an 8-month period by collecting the particles directly onto TEM grids in anthropogenically-influenced (vineyard) and pristine (native forest) sites in France. Particle clusters trapped on the grid were selected randomly and individual particles were binned into eight different groups (euhedral clays, weathered clays, salts, oxi-hydroxides, bacteria, non-living organic matter, aggregates and undetermined). Bacteria represent 9–23% of the collected nanoparticle area (ave. 9.4% and 18% for two atmospheric collection sites and ave. 23% for soil infiltration samples). Bacteria were most often associated with non-living organic matter and comprised a variety of morpho-types. Interestingly, 45% of all the bacteria analyzed by transmission electron microscopy and electron dispersive spectroscopy (TEM-EDX) showed the presence of intracellular grains significantly enriched in lead and phosphorus. Intracellular sequestration of Pb into polyphosphate bodies has been observed in the laboratory, but this is the first observation of this phenomenon in a natural environment. Furthermore, this suggests that microbial-bound Pb may be an important transport mechanism in subsurface environments.  相似文献   

15.
大气环境变化的泥炭地质档案   总被引:2,自引:0,他引:2       下载免费PDF全文
雨养泥炭沼泽是一种重要的泥炭沼泽类型,具有全球广泛分布的特点,其养分补给主要源于大气降水(包括雨、雪和空气尘埃).它是一个记录大气环境变化的积极的信息储备系统,记录有大气输入的海盐气溶胶、沙尘颗粒、酸沉降、重金属和有机污染物等信息.采用地质定年技术将泥炭深度剖面转化到年代坐标上,并结合泥炭生物地球化学指标检测分析,提取...  相似文献   

16.
The global issue of atmospheric variations and global warming caused by diverse anthropogenic behaviors is a global concern. There is apprehension about preserving an uncontaminated atmosphere and attaining optimal nuclear and geothermal energy utilization with agriculture sector development. In this regard, this paper investigates the influence of nuclear energy, geothermal energy, agriculture development, and urbanization on carbon emissions and ecological footprint from 1990Q1 to 2019Q4 in the case of China. The findings of unit root tests reveal that all variables are stationary at first integration order, and cointegration test findings confirm the presence of long-run relationships among series. The quantile autoregressive distributive lag (QARDL) method findings demonstrate that nuclear energy, geothermal energy, and urbanization statistically correlate with CO2 emissions and ecological footprint across all quantiles, indicating that these determinants have contributed to environmental degradation. Whereas agricultural development has a statistically significant and negative influence on the environment, implying that agriculture has a pollution-mitigation impact. Based on these empirical findings, several policy implications are presented to preserve environmental quality to achieve the 2030 Sustainable Development Goals (SDGs) target.  相似文献   

17.
土壤有机碳的主导影响因子及其研究进展   总被引:61,自引:0,他引:61  
土壤有机碳库是全球碳循环的重要组成部分,其积累和分解的变化直接影响全球的碳平衡。理解土壤有机碳蓄积过程对生物、物理和人为因素的响应,把握关键的控制因子是准确预测土壤有机碳在全球变化情景下对大气CO 2的源/汇方向及准确评估碳收支的关键。综述了土壤有机碳主导影响因子的研究进展,并针对陆地碳循环特点,提出未来土壤有机碳研究应加强土壤有机碳过程与状态的定量化、土壤有机碳分解对环境因子的敏感性、氮沉降对土壤有机碳的影响、土壤有机碳对气候变率的响应及其反馈作用,以及土壤有机碳动态的综合模拟 5个方面的研究,为准确评估陆地碳收支提供依据。  相似文献   

18.
数字地球及其在全球变化研究中的应用前景   总被引:4,自引:0,他引:4       下载免费PDF全文
孙枢  史培军 《第四纪研究》2000,20(3):213-219
本文介绍了对“数字地球”的不同学术理解和当前国内外数字地球发展重点领域或方向,展望了“数字地球”在全球变化研究中的应用前景,指出在第四纪环境演变研究中要重视广泛应用对地观测技术,建立数据库,进而阐明全球变化的区域响应过程,揭示区域和全球变化过程中人与自然在其中的作用程度,为可持续发展模式的建立提供科学依据。  相似文献   

19.
《Comptes Rendus Geoscience》2014,346(3-4):53-63
Natural organic matter (OM) is widespread in terrestrial ecosystems and it plays a major role in the global carbon cycle. Despite this high environmental importance, its characterization at the molecular level remains unsatisfactory, especially when the macromolecular OM is concerned. Such a characterization is challenging because of the diversity and heterogeneity of OM, but it is of prime importance to derive OM reactivity and, more generally, to model environmental processes in which natural OM is involved. This awareness led to a wealth of analytical developments, which are described in the present review. They include improvements of existing techniques, but also new approaches and concern spectroscopic tools along with chemical and thermal degradations.  相似文献   

20.
The organic content of a number of sediments from the Carboniferous of northern England have been examined as a function of their depositional environment. Extraction of the sediments yielded the soluble organic matter whilst microscopic examination of polished blocks of shales enabled the detection of particles of organic detritus. A relationship between the amount of extract and the quantity of terrestrial plant material in the sediments has been established. However, the yield of extract (mg/g org. C) is higher in the more marine environment than the nonmarine environment. The proportion of saturated hydrocarbons in the extract appears to be related to the amount of identifiable organic matter (coal macerals) in the sediment. The n-alkane distribution patterns have been compared with these obtained from coal macerals. The suggestion that the pristane to phytane ratios may reflect the source material of the organic matter has been examined.  相似文献   

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