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791.
792.
目前关于原油对淡水水生脊椎动物内分泌信号的潜在影响的认知有限。本文以非洲爪蟾(爪蟾属,X. laevis)蝌蚪和莫桑比克罗非鱼幼鱼(口孵非鲫属,O. mossambicus)为研究对象,选择风化原油和未风化提炼后的原油这2种原油的水溶性组分(WAFs)进行暴露实验,选择出可作为内分泌信号改变的生物标志物的基因,对其表达进行了研究。此外,将X. laevis蝌蚪暴露于靠近地下石油库的地表水中,对上述基因表达做了定量分析。利用重组酵母对原油、原油水溶性组分和地表水的(抗)雌激素和(抗)雄激素性进行了评价。在X. laevis对2种原油WAFs的响应中,甲状腺激素受体β表达均显著下调,而另一种与甲状腺相关的基因,2型脱碘酶,在O. mossambicus暴露于高浓度的原油WAF时被上调。此外,这2种WAFs都改变了与脂肪生成相关的过氧化物酶体增殖物激活受体γ在X. laevis中的表达。原油和WAFs在体外表现出抗雌激素和抗雄性激素的活性。然而,O. mossambicus雄激素受体2作为唯一一个代表生殖系统的基因,受到WAF暴露的影响显著。在地表水样品中发现了雌激素、抗雌激素和抗雄激素的作用;但是,在暴露于地表水的X. laevis中没有观察到任何基因表达的明显变化。在所用的2种模式生物以及2种原油中,响应各不相同。尽管如此,这些数据提供了证据证明原油污染可能会因内分泌信号转变对淡水鱼和两栖动物的健康造成不利影响。
精选自Truter, J. C., van Wyk, J. H., Oberholster, P. J., Botha, A.-M. and Mokwena, L. M. (2017), An evaluation of the endocrine disruptive potential of crude oil water accommodated fractions and crude oil contaminated surface water to freshwater organisms using in vitroand in vivo approaches. Environmental Toxicology and Chemistry, 36: 1330–1342. doi: 10.1002/etc.3665
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3665/full 相似文献
793.
Environment, Development and Sustainability - The Ganga-Padma moribund deltaic zone contains plenty of small seasonal wetlands. In this paper we mapped the temporal hydrological dynamics of... 相似文献
794.
Karki Sikha Burton Paul Mackey Brendan Alston-Knox Clair 《Environment, Development and Sustainability》2021,23(10):14642-14665
Environment, Development and Sustainability - Like other low-income countries in Asia and Africa, Nepal still suffers from food insecurity with a large proportion of food-insecure households being... 相似文献
795.
JamesDMcCurry PaulZavitsanos 《环境化学》2004,23(1):113-116
利用气-质和液相/电喷雾-质谱联用仪对商用杀菌剂进行了分析.其中,气-质联用可用于分析杀菌剂中的挥发性化合物,但是对于活性化合物,如嗪氨灵,却不能分析.电喷雾/液质联用可以分析嗪氨灵和不挥发的表面活性剂及污染物.本文介绍了气-质和液相/电喷雾-质谱联用仪用于分析商用杀菌剂,结果表明,两种技术具有互补性. 相似文献
796.
Carol C. House J. Jeffery Goebel Hans T. Schreuder Paul H. Geissler William R. Williams Anthony R. Olsen 《Environmental monitoring and assessment》1998,51(1-2):451-463
A demonstration project in Oregon examined the feasibility of combining Federal environmental monitoring surveys. An integrated approach should remove duplication of effort and reduce the possibility of providing apparently conflicting information to policy makers and the public. Data collection teams made photo interpretation measurements and on-site soil/vegetation/animal observations at locations that were selected from the Forest Inventory and Analysis (FIA), National Forest System (NFS) Region 6, and National Resource Inventory (NRI) surveys in a six-county area in Northern Oregon. The project demonstrated the feasibility of conducting a combined FIA/NFS/NRI survey and suggests an approach that will preserve the utility of the critical historical information from these surveys. We suggest a framework for estimating the extent of forest and range land that explains FIA/NRI differences and provides a common basis for both surveys. We suggest indicator and protocol criteria that will allow consistent national and regional estimates over all vegetation types, and stress the importance of including measurement repeatability in the design of the combined survey. 相似文献
797.
Wayne R. Davis Andrew F.J. Draxler John F. Paul Joseph J. Vitaliano 《Environmental monitoring and assessment》1998,51(1-2):259-268
It is proposed that the common measures of benthic community condition can be augmented with a vertical EH profile taken through the benthic bioturbation zone. Sediment EH, an electrochemical measure of oxidized and reduced compounds in sediment porewater, measures the integrative consequences of all metabolic and transport processes of the benthic community. Biota, especially microbiota, metabolize carbon using a variety of electron acceptors, including O2, SO4 and some nitrogen and metal compounds. Motile benthic macrofauna ingest and transport particles, ventilate deep burrows and anoxic sediment with overlying seawater while sedentary suspension-feeding fauna deposit suspended organic matter onto the sediment surface. Collectively, these metabolic and behavioral processes advect particles and seawater between bottom water and deep sediment and define the overall structure of porewater chemistry. That structure creates a full spectrum of biogeochemical conditions of solubility, reactivity, and microbial metabolism which remineralizes excess organic carbon and most organic contaminants, defines solubility of trace metals, and pushes the vertical EH profile toward oxidizing conditions. It is proposed that a standard EH probe inserted downward through the bioturbation zone will provide a general measure of this resulting porewater chemistry and thus the impact of feeding, irrigation, and metabolism of the total macro, meio, and microbenthic community. If such a measure can be validated it will permit extended measurement of community function and reduced efforts in measuring community structure. 相似文献
798.
The National Biomonitoring Specimen Bank (NBSB), established in 1979 at the NIST Neutron Research Facility, Gaithersburg, Maryland, was specifically designed to store environmental specimens over long periods of time (50-100 years). This bank contains specimens (e.g., human livers, marine sediments, fish tissues, mussels, oysters, human diet samples, and marine mammal tissues) collected as part of several monitoring and research programs supported by U.S. Federal agencies. In 2002, NIST completed the construction of a second environmental specimen bank facility specifically designed for supporting monitoring and research on marine environmental health issues. This facility, the Marine Environmental Specimen Bank (Marine ESB) is located at the Hollings Marine Laboratory in Charleston, South Carolina, in partnership with a U.S. Federal resource agency, two universities, and a State of South Carolina resource agency. The Marine ESB provides a resource of research specimens that are used to address questions regarding temporal and geographic trends in environmental contamination, genetic separation of populations of animals, and the health status of various types of marine animals. Specimens banked include marine mammal tissues, bird tissues, mussels, and oysters. Plans are underway to establish protocols and initiate banking procedures for other types of marine organisms and environmental materials as part of an expanded effort to support research on the health of marine biota. 相似文献
799.
Tina Sanders Claudia Fiencke Matthias Fuchs Charlotte Haugk Bennet Juhls Gesine Mollenhauer Olga Ogneva Paul Overduin Juri Palmtag Vasily Povazhniy Jens Strauss Robyn Tuerena Nadine Zell Kirstin Dhnke 《Ambio》2022,51(2):423
The Arctic is nutrient limited, particularly by nitrogen, and is impacted by anthropogenic global warming which occurs approximately twice as fast compared to the global average. Arctic warming intensifies thawing of permafrost-affected soils releasing their large organic nitrogen reservoir. This organic nitrogen reaches hydrological systems, is remineralized to reactive inorganic nitrogen, and is transported to the Arctic Ocean via large rivers. We estimate the load of nitrogen supplied from terrestrial sources into the Arctic Ocean by sampling in the Lena River and its Delta. We took water samples along one of the major deltaic channels in winter and summer in 2019 and sampling station in the central delta over a one-year cycle. Additionally, we investigate the potential release of reactive nitrogen, including nitrous oxide from soils in the Delta. We found that the Lena transported nitrogen as dissolved organic nitrogen to the coastal Arctic Ocean and that eroded soils are sources of reactive inorganic nitrogen such as ammonium and nitrate. The Lena and the Deltaic region apparently are considerable sources of nitrogen to nearshore coastal zone. The potential higher availability of inorganic nitrogen might be a source to enhance nitrous oxide emissions from terrestrial and aquatic sources to the atmosphere.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01665-0. 相似文献
800.
David W. Bressler Michael J. Paul Alison H. Purcell Michael T. Barbour Ed T. Rankin Vincent H. Resh 《Journal of the American Water Resources Association》2009,45(2):291-305
Abstract: This is the first in a series of three articles designed to establish empirically defined biological indicators and thresholds for impairment for urbanized catchments, and to describe a process by which the biological condition of waterbodies in urbanized catchments can be applied. This article describes alternative gradients of urbanization for assessing and selecting a nationally applicable biological index (article 2 – Purcell et al., this issue ) and defining the potential of biological communities within a gradient of cumulative stressors (article 3 – Paul et al. this issue ). Gradients were designed to represent the most prominent mosaic of stressors found in urban settings. A primary urban gradient was assembled based on readily obtained information of urbanization to include three broad‐scale parameters: percent urban land use/land cover, population density, and road density. This gradient was used as the standard by which alternative urban gradients, which included fine‐scale instream chemical and hydrologic parameters, were assessed. Five alternative gradients were developed to provide numerous environmental management options based on availability of data from water program resources. The urban gradients were developed with the intent that they be applied throughout the country; therefore, data from three different regions of the United States (Mid‐Atlantic, Midwest, and Pacific Coast) were used to validate the urban gradient model. Our study showed that a relatively straightforward stressor gradient consisting of human population density, road density, and urban land use is useful in providing a framework for developing relevant biological indicators and evaluating the potential of biological communities as a basis for assessing attainment of designated aquatic life use. 相似文献