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1.
随着溴系阻燃剂在世界范围内被禁止,其主要替代物有机磷酸酯(OPEs)在近年来的生产和使用量均呈现快速增长.但作为塑料添加剂,OPEs与材料间无化学键束缚,极易在产品生命周期中释放进入环境.目前,OPEs作为一类新兴污染物,已在全球各地的污水、自来水及其它各类环境介质和人体中广泛检出,包括极地地区,表现出长距离迁移能力,因此,其环境污染和毒性迅速受到国内外的广泛关注,但目前对其环境行为和潜在风险尚不完全清楚.本文对近15年来发表的相关文献进行了检索,综述了OPEs在各类环境介质和人体中的污染特征和现状、迁移转化行为、毒性和分析方法的研究进展.结果表明:OPEs在全球环境中普遍存在,可通过室内灰尘接触、呼吸、食物链传递等途径被生物体和人体吸收,并表现出内分泌干扰、神经毒性、生殖发育毒性等多种毒性效应;OPEs在生物体/人体中可被转化为低取代的二酯、单酯等代谢产物,但目前对其代谢转化途径尚不明确.鉴于OPEs生产使用历史悠久,用途广泛且用量巨大,污水处理去除效率有限,其环境行为过程和机理以及由此导致的潜在生态和健康风险值得引起持续关注.此外,OPEs种类繁多,化合物之间性质差异较大(lg K...  相似文献   

2.
氯代多环芳烃(Chlorinated polycyclic aromatic hydrocarbons,Cl-PAHs)作为多环芳烃的氯代衍生物,具有类似二英的致癌、致畸、致突变毒性,并且广泛存在于环境介质中,对生态环境和人类健康具有一定的潜在威胁.本文介绍了Cl-PAHs在不同环境介质中的分析方法、污染现状、迁移转化及其毒性效应,最后对其未来研究方向进行了展望.在今后,应该加强污泥和沉积物等复杂环境基质中Cl-PAHs的分析方法研究;系统研究ClPAHs在环境介质中的污染现状和迁移转化行为,并开展Cl-PAHs的环境风险和人体健康风险研究.  相似文献   

3.
有机磷酸酯阻燃剂的环境暴露与迁移转化研究进展   总被引:3,自引:0,他引:3  
有机磷酸酯(organophosphate esters,OPEs)是目前被广泛使用的阻燃剂添加成份,其具有神经、生殖、基因等生物毒性,且具有致癌性。作为新一类污染物,有机磷酸酯在环境中越来越多的释放引起了环境研究者的关注。文章综述了OPEs在水体、土壤、空气和生物体中的暴露浓度,并介绍了OPEs在环境中的各种迁移转化途径。目前针对OPEs的环境暴露研究仍十分有限,需要更全面调查其在多环境介质中的暴露状况以综合评价其生态风险。OPEs的多种迁移途径已得到证实,但相关物理化学转化和生物转化机制研究尚不完整。最后对OPEs的进一步研究提出了展望,以期促进我国OPEs的生态风险研究。  相似文献   

4.
有机磷酸酯(organophosphate esters, OPEs)的大量应用使其在多种环境介质以及生物体内被不断检出,其对生态环境和生物体的威胁越来越引起人们的关注。随着经济和社会的发展,我国的生态环境尤其是近岸海洋遭受到了大量有害物质的污染,这将对生态及养殖环境健康和水产品安全产生不利影响。本文对有机磷酸酯在我国近海养殖区域水生生态系统(海水、沉积物及生物)中的残留状况、生物富集特征、毒理信息、迁移转化、生态风险以及健康风险进行了总结和分析。我国近海养殖区域已普遍遭受到OPEs不同程度的污染,OPEs的生物毒性效应以及生物富集作用也被证实,但考虑到生态环境的复杂性和多样性,以及生物体内存在的多种生物化学反应,OPEs在环境及生物中的赋存状况和污染特征,以及生物富集和迁移转化的相关影响因素和机制仍值得关注。本文最后对目前OPEs的相关研究存在的问题和不足进行了分析并提出了研究展望,以期对OPEs的综合研究提供参考和见解。  相似文献   

5.
有机磷酸酯(organophosphate esters,OPEs)是使用最为广泛的有机磷阻燃剂,并兼具增塑剂、消泡剂和萃取剂等功能,被广泛用于电子产品、建筑材料和塑料材料等中,导致其在环境介质中普遍存在,对生态系统和人体健康构成巨大威胁.作为一种新型环境污染物,OPEs的人群暴露特征和生物毒性成为环境健康领域的研究热...  相似文献   

6.
有机磷酸酯(organophosphate esters,OPEs)在各类环境介质中被频繁检出,且对生态系统和人体健康存在潜在危害,其环境归趋已成为环境科学领域的热点问题.植物作为陆生食物链的重要环节,也是污染物的重要存储体之一,关于植物体吸收、积累OPEs及其在植物体内迁移转化的研究,对明确OPEs的环境行为、评价其生态风险以及科学使用和管理具有重要意义.本文就近年来关于OPEs在植物体内归趋的研究进行汇总,综述了植物吸收OPEs的主要方式、积累以及OPEs在植物体内的迁移与转化行为及其影响因素,并展望了未来研究趋势和发展方向. OPEs主要通过被动扩散被根系吸收;辛醇-水分配系数(octanol-water partition coefficient,Kow)是影响植物吸收、积累和迁移OPEs的关键因素,植物根系对lg Kow值为3.5—9.5间的OPEs吸收速率更快;lg Kow<3的OPEs更易通过植物木质部和韧皮部进行运输. OPEs在植物中的吸收、积累和迁移还受植物根系的蛋白质、脂质含量以及蒸腾能力等生...  相似文献   

7.
有机磷酸酯(organopho sphate esters,OPEs)作为阻燃剂和增塑剂广泛应用于建筑材料和电子产品等材料,随着生产和使用量的增加,导致其普遍存在于各种环境介质中.作为一类新污染物,OPEs的环境行为及归趋引起了越来越多环境学者的关注.本文系统阐述了OPEs在环境中可能发生的物理、化学和生物过程.现有研究表明:(1)OPEs自身理化性质和结构(疏水性和π-π效应)是影响其迁移转化过程的重要因素;(2)复杂的介质环境(温度、pH值、溶解性有机质、氧化活性物种等)能够影响OPEs的大气传输/沉降、吸附/解吸、水解、光解、生物富集和植物吸收等过程;(3)OPEs在迁移转化中能生成二酯或单酯类产物(化学键断裂)、羟基化产物、甲氧基化产物以及其他小分子化合物等.针对目前的研究现状建议未来可重点关注OPEs在小型生态系统中多介质中的迁移转化过程与机制以及在迁移转化过程中生成产物的理化特性与生物效应等.  相似文献   

8.
抗生素环境行为及其环境效应研究进展   总被引:7,自引:0,他引:7  
抗生素作为一类抗菌性药物广泛用于预防和治疗人类和动物疾病,并且在畜牧和水产养殖业中用于促进动物的生长.进入人和动物体内的抗生素不能被生物体完全吸收,大部分以原药或代谢物的形式经由尿液和粪便排出体外进入环境中.抗生素是环境中一类新型污染物,由于其使用量大和诱导产生抗生素耐药菌株,对人类健康和生态环境构成威胁,近年来受到日益广泛的关注.抗生素诱导产生的抗性基因(ARGs)也已经被定义为环境中一类新型污染物.本文介绍了抗生素的使用现状、环境来源以及不同环境介质中抗生素的分析方法和污染现状,并且对其吸附降解行为、毒性效应以及ARGs进行了讨论,最后指出了目前研究中存在的问题,并对未来研究进行了展望.在今后,应该更加系统地研究环境中抗生素的污染现状及其迁移转化等行为;开展低剂量长期慢性毒性和复合毒性效应研究;加强对环境中ARGs的污染现状和环境行为研究.  相似文献   

9.
作为最主要的三大传统溴系阻燃剂(BFRs),多溴联苯醚(PBDEs)、六溴环十二烷(HBCD)、四溴双酚A(TBBPA)具有半挥发性、环境持久性和远距离传输性,目前在全球各种环境介质、生物体内广泛存在.毒理学研究表明,PBDEs、HBCD、TBBPA均具有明显的生物毒性和致癌性,对生态环境和人体健康存在潜在危害.本文简要概述了PBDEs、HBCD、TBBPA的使用现状,综述了全球范围内非生物体(灰尘、水体、土壤、沉积物、污泥)和生命体内(植物、动物、人体)等3种传统BFRs的污染水平、特征、暴露途径和毒性,并讨论了当前存在问题,最后对PBDEs、HBCD、TBBPA的未来研究进行了初步展望.  相似文献   

10.
随着世界范围内对溴代阻燃剂的禁用,有机磷阻燃剂(OPFRs)被作为替代品广泛应用于建筑、纺织、化工、电子以及家装材料等行业,生产和使用量逐年上升.由于OPFRs在环境和生物体中普遍检出,且多种化合物具有致癌性、神经毒性和生殖毒性,对生态环境和人体健康造成潜在威胁,目前已成为国际上的一个研究热点.笔者重点综述了河流、湖泊和海洋等水体及沉积物中OPFRs污染现状,水生生物对OPFRs的生物富集和生物放大,以及OPFRs在水生生物体内和体外生物代谢的研究进展,并对目前该领域仍有待探讨的问题及研究趋势进行了展望.  相似文献   

11.
Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación  相似文献   

12.
A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.  相似文献   

13.
Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.  相似文献   

14.
Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.  相似文献   

15.
An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.  相似文献   

16.
Summary Two South American polyphagous leaf beetles,Diabrotica speciosa andCerotoma arcuata, selectively accumulated the bitter tasting compound 23,24-dihydrocucurbitacin D in their body after ingesting root tissues of cucurbit plants. Similarly, three Asian Cucurbitaceae-feeding specialists in the genusAulacophora were found to sequester the same compound. Cucurbitacin analogs were shown to deter feeding by a bird predator, indicating an allomonal role for these compounds in cucurbitacin-associated chrysomelid leaf beetles both of New and Old Worlds. The strong affinity to cucurbitacins, selective sequestration of the analogs and consequent protection from predators suggested an ecological adaptation mechanism developed in common among these two geographically isolated subtribes in the Luperini.  相似文献   

17.
Large, intact areas of tropical peatland are highly threatened at a global scale by the expansion of commercial agriculture and other forms of economic development. Conserving peatlands on a landscape scale, with their hydrology intact, is of international conservation importance to preserve their distinctive biodiversity and ecosystem services and maintain their resilience to future environmental change. We explored threats to and opportunities for conserving remaining intact tropical peatlands; thus, we excluded peatlands of Indonesia and Malaysia, where extensive deforestation, drainage, and conversion to plantations means conservation in this region can protect only small fragments of the original ecosystem. We focused on a case study, the Pastaza‐Marañón Foreland Basin (PMFB) in Peru, which is among the largest known intact tropical peatland landscapes in the world and is representative of peatland vulnerability. Maintenance of the hydrological conditions critical for carbon storage and ecosystem function of peatlands is, in the PMFB, primarily threatened by expansion of commercial agriculture linked to new transport infrastructure that is facilitating access to remote areas. There remain opportunities in the PMFB and elsewhere to develop alternative, more sustainable land‐use practices. Although some of the peatlands in the PMFB fall within existing legally protected areas, this protection does not include the most carbon‐dense (domed pole forest) areas. New carbon‐based conservation instruments (e.g., REDD+, Green Climate Fund), developing markets for sustainable peatland products, transferring land title to local communities, and expanding protected areas offer pathways to increased protection for intact tropical peatlands in Amazonia and elsewhere, such as those in New Guinea and Central Africa which remain, for the moment, broadly beyond the frontier of commercial development.  相似文献   

18.
Abstract: In East Africa fire and grazing by wild and domestic ungulates maintain savannas, and pastoralists historically set fires and herded livestock through the use of temporary corrals called bomas. In recent decades traditional pastoral practices have declined, and this may be affecting biodiversity. We investigated the effects of prescribed fires and bomas on savanna bird communities in East Africa during the first and second dry seasons of the year (respectively before and after the rains that mark the onset of breeding for most birds). We compared abundance, richness, and community composition on 9‐ha burned plots, recently abandoned bomas, and control plots in the undisturbed matrix habitat over a 3‐year period. Generally, recently burned areas and abandoned bomas attracted greater densities of birds and had different community assemblages than the surrounding matrix. The effects of disturbances were influenced by interactions between primary productivity, represented by the normalized difference vegetation index, and time. Bird densities were highest and a greater proportion of species was observed on burned plots in the months following the fires. Drought conditions equalized bird densities across treatments within 1 year, and individuals from a greater proportion of species were more commonly observed on abandoned bomas. Yearly fluctuations in abundance were less pronounced on bomas than on burns, which indicate that although fire may benefit birds in the short term, bomas may have a more‐lasting positive effect and provide resources during droughts. Several Palearctic migrants were attracted to burned plots regardless of rainfall, which indicates continued fire suppression may threaten their already‐declining populations. Most notably, the paucity of birds observed on the controls suggests that the current structure of the matrix developed as a result of fire suppression. Traditional pastoralism appears critical to the maintenance of avian diversity in these savannas.  相似文献   

19.
20.
How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.  相似文献   

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