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P. Malessa 《Marine Biology》1969,3(2):143-158
Previous authors have demonstrated that changes in O2-consumption of predominant muscle tissue (in vitro) do not account for the variations in O2-consumption of a resting intact eel induced by differences in adaptation temperature (AT). The present paper is concerned with the metabolism of the eel's lateral muscle. Activity of cytochrome oxidase and succinate dehydrogenase, expressed in terms of O2-consumption, are higher in the red muscle portion than in the white one (the factors are 6 to 10 and 2 to 3, respectively). In epaxial muscle strips from some 10 cm behind the anus, red muscle tissue comprises between 44% and more than 60% of the total lateral muscle cytochrome oxidase activity, even though, in this region, the relative weight of the red portion makes up only 11 to 14.5% of the total muscle. The red muscle portion is still smaller in the region anterior to the anus, and its total cytochrome oxidase activity (enzyme activity x relative weight) much lower. Cytochrome oxidase activity remains rather unchanged in the white portion of the muscle. Since the metabolism of white muscles is primarily glycolytic, it is remarkable that — with respect to the terminal oxidative metabolism — tissue temperature adaptation in the eel is more pronounced in red muscles than in white ones. In juvenile and adult eels, acclimated to seasonal temperature, the total cytochrome oxidase activity of the white muscle undergoes little change. However, in cold-acclimated adults with extensive pigmentation, aerobic metabolism of red muscles is favoured; this is indicated both by extremely high cytochrome oxidase activity and increased relative muscle weight. Increased aerobic metabolism of red muscle tissue is, therefore, assumed to be important, especially during the winter spawning migration. 相似文献
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Simone Wünschmann Jörg Oehlmann Bernd Delakowitz Bernd Markert 《Environmental Sciences Europe》2001,13(5):259-265
The objective of the current attempt was to investigate the suitability of wild-living rats (Rattus norvegicus) as a passive bioindicator using quantitative determinations of 12 chemical elements in different organs taken from rats which were caught in the Zoological Garden of Zittau. Aside from the determinations of so-called background levels, the focus of interest was with accumulations of certain elements within the organs depending on either sex or age of the rats. There were different affinities of the elements towards certain organs. Because of apparent sex and age-related differences in element concentrations and accumulation features, a well-planned sampling strategy for the use of rats as possible passive bioindicators is indeed required. The consideration of element distribution patterns within the organ system of Rattus norvegicus (based on body burden calculations (in part 2 of this work)) allows an effective use of the rat for purposes of integrative monitoring. 相似文献
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Simone Wünschmann Jörg Oehlmann Bernd Delakowitz Bernd Markert 《Environmental Sciences Europe》2002,14(2):96-103
Depot compartments which are the primary sites of pollutant enrichment in the organism can be used as bioindicators (targets) in order to identify a burden for certain elements. Background concentrations of eleven elements in tissues and organs of wild-living rats (Rattus norvegicus) obtained from a region (Euroregion Neisse, around the trilateral border region of Germany, Poland and the Czech Republic) distinguished by low to intermediate levels of environmental contaminations are given in part I of this work. In order to identify the most important depot compartments for certain elements, a body burden method was applied. Differences of affinity due to sex and age of analyzed rats are discussed, as are the suitability of specific organs and tissues with regard to bioaccumulation measurements concerning metals. The principal depot compartments for the heavy metals Cu, Mn, Cd (in adult rats) and Tl are the liver and kidneys, whereas the elements Ni, Sr, Pb (for adult animals) and Ti are more affinitivly to bones. Co and Zn displayed a more pronounced affinity towards tissues of the bones and liver. The analysis revealed large differences in Cd and Pb distributions both among young and adult rats, and with respect to sexes. It can be concluded that the distribution of the elements investigated in this study in free-living rats agrees with that in man, except for that of Ni. The above agreement gives proof of the possibility to use depot organs of rats for bioindication which was already mentioned in part I of this work (‘Sex and age-related quantification of Al, As, Cd, Co, Cu, Mn, Ni, Pb, Sr, Ti, Tl and Zn in liver, heart, lung, kidney, muscle, brain and bones and establishment of distribution patterns’). 相似文献
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由于潜在生态毒理数据的限制,生态周期影响评估中的毒性模型仅仅描述了市场上的一小部分物质。改进现有的LCIA数据情况可以通过发现新的数据来源,比如欧盟化学品注册、评估、授权和限制(REACH)数据库。本研究通过对比记录在REACH数据库和UNEP/SETAC的科学统一模型USEtox中相同化学物质的生态毒理数据来探究REACH是否具有作为数据来源的潜力。数据根据数据点的个数,报道可靠性和测试时间评估,并将每种化学物质的50%涵盖物种的危险浓度与USEtox中的数据做对比。结果强调了REACH和USEtox之间不同的数据可用性。REACH和USEtox的生态毒理学数据对比表明REACH是一个LCIA毒性鉴别的潜在生态毒理学数据来源,也显示出REACH标准的数据存在着一致性的问题,以及REACH中监管风险评估的假设可能与LCIA所需数据有出入。因此,在考虑REACH标准下的数据在LCIA的运用之前,数据质量,预处理和可运用性需要进一步的研究。探究其他可用的数据来源,发表的研究与报告也需要更深入的调查。
精选自Nienke Müller, Dick de Zwart, Michael Hauschild, Ga?l Kijko, Peter Fantke. Exploring REACH as potential data source for characterizing ecotoxicity in life cycle assessment. Environmental Toxicology and Chemistry: Volume 36, Issue 2, pages 492–500, July 2017.
DOI: 10.1002/etc.3542
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3542/full 相似文献
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In line with the aims of waste management, the handling of waste should hinder any damage to the environment as much as possible. There are a number of approaches for solving this action in practice, e.g. different treatment technologies for residual waste, from which the most favourable should be chosen. We have several different methods for supporting such choices. An evaluation of studies published in recent years that assess waste management measures has clearly showed that the impact on the environment alone is not a sufficient basis for decision-making. In most cases, the cost aspect is also of primary concern while the technical implementation and social aspects also have to be taken into consideration. In recent years a great number of assessment methods have been developed as tools in the decision-making process. However, the multitude of methods leads to different results depending on the methods, parameters and criteria of the research. The following paper will characterise the most important decision-making concepts, such as the Life Cycle Assessment, Product Line Analysis, Cost-Benefit Analysis, Scoring Model, etc. Examples will show how these methods can be applied to the issues of waste management. The conclusion will describe the current state of development for waste management applications. 相似文献
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For studies of in situ interactions between plankton and ambient water, simple, cylindrical, 5 m deep translucent-foil tanks were constructed using polyamide and polyethylene (layers 30 and 100 μm, respectively, with polyamide layer outside). The tanks were suspended in the water by metal frames fixed to a buoy. The whole construction was anchored in an outer basin of the harbour of Helgoland, N. Sea, and was exposed to tides and waves generated by winds of up to 6 Bft (Beaufort scale). Even under these conditions the construction and its material allowed experiments lasting 2 weeks and longer, during the summer months of 1972 and 1973. The banks' volume, of about 4 m3 each permits experiments with naturally occurring concentrations of nutrients and organisms and large sampling volumes for the determination of trace components. In this way, natural plankton populations in 1972, and monocultures of different diatom species in 1973 were investigated. Under these conditions, different monocultures developed almost identically. 相似文献
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The deposition of untreated waste is illegal after the year 2005 on account of the new Technical Instructions for Housing Refuse (Technische Anleitung (TA) Siedlungsabfall). Therefore, the thermal treatment of waste is becoming more important than in the past. The traditionally used grate firing with steam boilers has potential for improvement. The characteristics of the different types of pyrolysis processes are explained and compared using the experience of projects planned, or already realized, in the state of Bavaria. This paper takes credit of the waste pyrolysis plant in Burgau, which is in operation since 1983, and the advanced pyrolysis plants in Fürth (Schwelbrenn-process) and in Ansbach (Thermoselect-process). The conversion-process is another newly developed method of thermal waste treatment. Some information will also be given about the pyrolysis plant for plastics in Ebenhausen. A comparison of the emission of conventional grate firing, and of 2-stage pyrolysis processes with the standards of the German laws for emission (17th BImSchV) shows, that all these processes, if planned correctly, meet the legal standards of emission. It is expected that in the future different thermal processes for waste treatment will prove successful, depending on the task. 相似文献
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The uptake and accumulation of the traffic-related platinum group elements (PGE) Pt, Pd and Rh by the aquatic fauna was investigated. Zebra mussels, eels and barbels were maintained in water containing either road dust or ground catalytic converter material. Following the exposure, samples of fish liver and kidney, as well as the soft tissues of the mussels, were analysed. Our results revealed that all three catalytic noble metals were accumulated by aquatic organisms. The highest bioavailability was found for Pd, followed by Pt and Rh. The concentration factor of Pd forDreissena polymorpha was 5 times higher compared with Pd and only 6 times lower than the essential element Cu. With regard to the increasing emission of Pd the level of this metal has to be monitored very carefully in the environment. 相似文献
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Simple biotests are frequently used for the ecotoxicological assessment of waste water. Unfortunately, and not too rarely, effects are detected and the question concerning water-polluting substances has to be answered. The latter are enriched by solid phase extraction (SPE), then isolated and fractioned by thinlayer chromatography using automatic multiple development (AMD). One strip of the DC-plate is separated and used without further atterations for the biological detection with microorganisms (Bacillus subtilis, luminous bacteria). With this system, toxic bands can be identified. From the other part of the DC plate, an UV-spectrum can be taken of the toxic bands using a DC scanner. Subsequently, the corresponding bands are scratched out and the toxic substance is eluted and analysed with infrared spectroscopy. The infrared spectrum can be characterised by comparing it with reference spectra. In this submitted work, a concept is presented with an example of a “nipple rubber” eluate. It shows that this rubber article liberates a vulcanization accelerator, 2-mercaptobenzothiazole. 相似文献
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B. L. Kojis 《Marine Biology》1986,91(3):311-318
In contrast to the seasonal gamete and planula production of Acropora (Isopora) palifera on Heron Island reef (Lat. 23° S), populations on Lizard Island reef (Lat. 14° S), sampled in 1979, 1981 and 1983, and Salamaua and Busama reefs (Lat. 7° S), sampled from 1980 to 1983, planulated year-round. Intensive sampling of colonies at Salamaua and Busama showed that gametes ripened at two-month intervals and that up to six cycles of gametes and larvae could be produced by an individual colony. Gametes of only a portion of the population — usually close to 50% — ripened each month. The Salamaua population, on average, produced fewer and smaller planulae than the Heron Island population during each two-monthly reproductive cycle. Hypotheses correlating the annual periodicity of breeding in marine animals with latitudinal variation of temperature were tested. In general, the time of breeding in A. palifera at Heron Island reef is much more restricted than theories based on latitudinal variations of water temperature would predict. It is hypothesized that, in the near subtropical environment of Heron Island reef, this species has evolved a life-history strategy that limits the amount of energy allocated to reproduction and allocates more energy to growth. 相似文献
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B. L. Kojis 《Marine Biology》1986,91(3):291-309
Despite the wide range of morphological diversity among the Acropora (Isopora) colonies on Heron Island (Great Barrier Reef, Australia), only two reproductively isolated species were present from 1977 to 1982: A. cuneata (Dana, 1846) and A. palifera (Lamarck, 1816). Both species released planulae lacking zooxanthellae and were simultaneous hermaphrodites with testes and ovaries occurring on separate mesenteries within the same polyp. Oogenesis preceded spermatogenesis. Seasonal cycles of gametogenesis, embryogenesis and planulation occurred in the two species. Colonies of A. cuneata developed two cycles of gametes. One cycle matured near the first quarter moon in April and the other on the same lunar phase in June. Planulae release occurred from about September to December each year and was not correlated with lunar phase. Gametes of A. palifera ripened only once per annum, a few days after the last quarter moon in November, and planulation occurred from about January to March. Embryos were brooded in the coelenteron of the polyps in both species. Ova were fertilized in the mesenteries and embryos were retained within an envelope of mesoglea and gastrodermis, remaining attached to the mesentery by a stalk until the larvae matured and were released. A. palifera and A. cuneata were abundant in the unpredictable reef flat environment. However, their life-history traits, e.g. seasonal reproduction, delayed sexual maturity, large colony size and fairly long life span, were more specialised than had been predicted for this type of environment. 相似文献