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291.
MESIP is a fugacity model which can predict the fate of organic hydrophobic chemicals in aquatic ecosystems. In this paper a short introduction to the mathematical model is presented together with a more detailed listing of the required input data. Comparison of the calculated and measured fate of a fluorescent whitening compound in an artificial outdoor pond is shown  相似文献   
292.
Research into the effects of ocean acidification (OA) on marine organisms has greatly increased during the past decade, as realization of the potential dramatic impacts has grown. Studies have revealed the multifarious responses of organisms to OA conditions, indicating a high level of intra- and interspecific variation in species’ ability to accommodate these alterations. If we are to provide policy makers with sound, scientific input regarding the expected consequences of OA, we need a broader understanding of these predicted changes. As a group of 20 multi-disciplinary postgraduate students from around the globe, with a study focus on OA, we are a strong representation of ‘next generation’ scientists in this field. In this unique cumulative paper, we review knowledge gaps in terms of assessing the biological impacts of OA, outlining directions for future research.  相似文献   
293.
SUMMARY

The rich plant diversity of the Indian Himalaya is utilized by the native communities in various forms as medicine, edible/food, fodder, fuel, timber, agricultural tools, etc. Among these, wild edible plants form an important source as a supplement/substitute food in times of scarcity for native communities. Because land holdings are small and subsistence agriculture prevails, the natives gather many wild plants for food. This paper presents an inventory of wild edible plants of Indian Himalaya used by local communities. Over 675 wild plant species, representing 384 genera and 149 families, are used as food/edible and their various parts are either consumed raw, roasted, boiled, fried, cooked or in the form of oil, spice, seasoning material, jams, pickles, etc. The species were analysed for diversity in different phytogeographical provinces, altitudinal distribution, endemism, origin and potentials. West Himalaya shows the highest diversity (50.96%) of edible plants and East Himalaya the maximum number of endemics (18 taxa) and wild relatives of economic plants (39 taxa). Mass scale propagation, dissemination of information packages to local inhabitants to ensure that wild edibles remain as a resource for income generation, and strategies for conservation and management are recommended.  相似文献   
294.
295.
Assisted migration of forest trees has been widely proposed as a climate change adaptation strategy, but moving tree populations to match anticipated future climates may disrupt the geographically based, coevolved association suggested to exist between host trees and ectomycorrhizal fungal (EMF) communities. We explored this issue by examining the consistency of EMF communities among populations of 40 year-old Douglas-fir (Pseudotsuga menziesii var. menziesii) trees in a common-garden field trial using four provenances from contrasting coastal climates in southwestern British Columbia. Considerable variation in EMF community composition within test sites was found, ranging from 0.38 to 0.65 in the mean similarity index, and the divergence in EMF communities from local populations increased with site productivity. Clinal patterns in colonization success were detected for generalist and specialist EMF species on only the two productive test sites. Host population effects were limited to EMF species abundance rather than species loss, as richness per site averaged 15.0 among provenances and did not differ by transfer extent (up to 450 km), while Shannon's diversity index declined slightly. Large differences in colonization rates of specialist fungi, such as Tomentella stuposa and Clavulina cristata, raise the possibility that EMF communities maladapted to soil conditions contributed to the inferior growth of some host populations on productive sites. The results of the study suggest locally based specificity in host-fungal communities is likely a contributing factor in the outcome of provenance trials, and should be a consideration in analyzing seed-transfer effects and developing strategies for assisted migration.  相似文献   
296.
Excessive discharge of nutrients in waters induces pollution such as such as eutrophication. Conventional methods to treat waters are expensive. Alternatively, anaerobic ammonium oxidation, termed “anammox”, has been recently developped with benefits such as low sludge production, 50% less aeration demand, no external carbon supply, 60% less power consumption, and 90% reduction of greenhouse gas emissions. However, anammox is limited by long start-up periods due to the low growth rate of anammox bacteria. This issue can be solved by complete retention of biomass by reactor modification or by formation of anammox granules. This article reviews the mechanisms of anammox granulation and biogranulation models. We present factors involved in the granulation processes such as hydrodynamic shear force, extracellular polymeric substances, hydraulic retention time, seed sludge and bioreactors. We also discuss the interaction of proteins and polysaccharides in anammox granules.  相似文献   
297.
为了研究不同经验驾驶人在高速公路特长隧道环境下的注视转移特性,在高速公路特长隧道中开展实车实验,利用 iView X HED型眼动仪采集了32名不同经验驾驶人的眼动数据。运用动态聚类方法,对驾驶人注视区域进行划分,分析了职业与非职业驾驶员在高速公路隧道不同段与普通路段的注视转移规律与注意力分配特性。结果表明:相较于非职业驾驶人,职业驾驶员具有较强的注视前瞻性,且在隧道的不同段主要注视的区域因行车环境不同变化较小;驾驶人对同一目标需要重复注视才能提取足够的信息,且当行车环境复杂度增加或驾驶员驾驶经验不足时,重复注视概率增加;驾驶人在不同路段行车时,主要通过注视中间区域获取信息;行车环境与驾驶经验对驾驶人在中间近处、左侧区域及内后视镜区域的注视平稳分布存在显著的交互作用。  相似文献   
298.
Background, aim, and scope Basically, technological innovations are associated with benefits and risks. This is also true for the introduction of genetically modified organisms (GMO) into agriculture. In Germany, precautionary regulations currently demand isolation distances (i.?e. buffer zones) for the cultivation of genetically modified maize (Bt-maize) in the vicinity of conventional (150?m) and organic maize fields (300?m). The Bt-toxin may harm non-target organisms (NTO) such as Lepidoptera. Despite this, corresponding regulations for the protection of nature reserves are lacking to date. Conventional and Bt-maize have been grown in the vicinity of the Flora-Fauna-Habitat (FFH) Ruhlsdorfer Bruch in Brandenburg, Germany. The aim of this study was to investigate whether exposure of maize pollen from surrounding Bt-maize fields to NTOs in the nature protection area could be excluded or not. Two types of exposure were investigated: Firstly, whether maize pollen was dispersed by wind into the nature reserve area exposing resident NTOs. Secondly, foraging NTOs from the nature reserve are exposed by roaming the surrounding fields and collecting maize pollen. In order to fulfil the precautionary principle defined by law, the study should help to determine appropriate isolation distances for the cultivation of Bt-maize with regard to sustainable protection of NTOs in the FFH Ruhlsdorfer Bruch. In 2007, the local authorities issued an isolation distance between Bt-maize fields and nature reserves of 100?m and in 2008, this became 250?m in the northern and 500?m in the westerly direction, respectively. Materials and methods Standardised methods for biological and technical pollen sampling issued by the Association of German Engineers (VDI 4330 Part 3, 2007 and VDI 4330 Part 4, 2006) were applied providing a quality controlled and methodologically harmonised database which does not only serve the needs to be fulfilled by the present case-specific monitoring study but can also be used as a reference database for further investigations. Maize pollen exposure was measured within the FFH Ruhlsdorfer Bruch and its immediate vicinity in July and August 2007 and 2008. In 2007, the sampling was performed at three sites using 12 technical samplers (Sigma-2/PMF) placed at five measuring points at distances from 5?m to 120?m from the maize field edges. Additionally, for biological pollen sampling six bee colonies were situated at these three sites (two colonies at each site). The technical sampler Sigma-2/PMF enables point sampling which is primarily influenced by wind and topography providing information on effective maize pollen input (flow and deposition) at the measuring sites. Honey-bees roaming in the surrounding area with typical foraging distances of several kilometres may act as planar collectors. They may serve as indicators for the exposure to pollen-collecting NTOs. Furthermore, biological sampling is more selective due to the organism’s preferences, whereas the technical sampling is neutral. Hence, both the technical and the biological sampling complement each other in their scope of application. The pollen samples of both matrices were analysed microscopically and the maize pollen loads were quantified. Pollen-DNA was analysed by means of the quantitative PCR-method (qPCR) identifying conventional and Bt-maize pollen by two independent laboratories. In 2008, the monitoring was repeated with additional sites. Eighteen technical samplers were exposed at five sites with eight measuring points at distances from 5?m to 250?m from the maize field edges. Two honey-bee colonies for biological sampling were placed at one site for control purposes. PCR-analyses were performed to measure the amounts of Bt-maize pollen in the samples. Results The results of pollen monitoring at the Ruhlsdorfer Bruch revealed maize pollen exposure for all monitoring sites in both surveys. In 2007, up to 1.75 million maize pollen/m² were deposited at sites closest to the maize field. At 120?m from field edge in the middle of the FFH-reserve, 99,000 maize pollen/m² were detected. In 2008, similar results were found, at distances up to 250?m from the field edges deposition of 164,000 maize pollen/m² was detected. Data on maize pollen deposition show a clear distance relationship and are in accordance with results of further comprehensive surveys based on the same methodology (Hofmann 2007). The results of the microscopic analysis of the pollen pellets demonstrated that bees collected maize pollen at all sites, in 2007 and 2008. Although maize pollen is not the main food source (2007:0.1–0.3?%; 2008:2–3?%) the collection efficiency of the bee colonies resulted in high amounts of sampled maize pollen with 4 to 11 million per site in 2007 and up to 467 million in 2008. Molecular-biological analysis of maize pollen DNA by qPCR demonstrated that transgenic Bt-MON810 DNA was present in all technical and biological samples, corroborated by two independent laboratories. In 2007, the GMO-content in the samples ranged up to 44?% in the bioaerosols and 49?% in the pollen pellets. In 2008, GMO-proportions of up to 18?% were detected. Discussion The results of this study provide evidence that NTOs in the Ruhlsdorfer Bruch were exposed to Bt-maize pollen under the cultivation conditions in 2007 with a buffer zone of 100?m. The GMO-content reached up to 48?%. The results of the monitoring in 2008 confirmed these findings. Even though the exposure could be reduced by increasing the isolation distances to 250?m and 500?m respectively, the results still show percentages of up to 18?% Bt-MON810 in the pollen samples. The results on maize pollen deposition at the Ruhlsdorfer Bruch in 2007 and 2008 correspond to the results of an investigation which was conducted over several years applying the same standardised method, but covering a wider range of distances. The correlation between maize pollen deposition (n/m²) and distance to the source field (m) fitted best to a power function of the type y = 1.2086 · 106 · x –0.548. Despite the same trend, the pollen deposition in the Ruhlsdorfer Bruch revealed above-average findings. Also the analysis of the pollen pellets collected by the bees showed an exposure in 2007 with values for the GMO-content of up to 49?%. For both methods, the exposure decreased in 2008 due to the greater buffer zones up to 500?m. Whereas the GMO-content for the biological sampling were reduced to values below 10?%, the values for the technical sampling were still higher indicating that greater buffer zones would be necessary for safety reasons under the precautionary principle. Conclusions The results of this investigation proved that maize pollen were dispersed by wind to distances farther than 250?m from field edge leading to maize pollen exposure in the centre of the nature reserve. The results also demonstrated that foraging NTOs living in the nature reserve were exposed to maize pollen from surrounding fields. Considering the cultivation of Bt-maize MON810, the assumption of the Environmental Risk Assessment (ERA) that there will be no relevant exposure beyond the Bt-maize fields, cannot be confirmed. Considering the results of this and related studies and with respect to the precautionary principle, one can state that buffer zones between Bt-maize fields and protected areas are an effective measure to minimise the exposure of Bt-maize pollen to NTOs and, thus, to prevent from adverse effects. Recommendations and perspectives Because of still insufficient ecotoxicological data for the risk assessment of Bt-maize MON810 considering butterflies and other protected NTOs, protection standards assuring the precautionary principle have to be implemented to avoid Bt-maize pollen exposure to NTOs. This applies for the case Ruhlsdorfer Bruch and for nature reserve areas in general. In order to exclude risks to protected NTOs occurring in nature reserves, sufficient buffer zones for Bt-maize cultivation should be considered. The statistical analysis revealed that distances of more than 500?m are necessary to decisively reduce exposure to foraging insects. In fact, distances of more than 1,000?m are necessary to prevent maize pollen deposition from values above 100,000 pollen/m² with a certainty of 90?%. An adequate risk assessment can only be attained if based on field measurements accounting for the high variation of pollen deposition due to local environmental site conditions and field management. The monitoring should be based on standardised methods. It should include locations with the highest expected deposition rates, the boundaries of the protected areas and sites of interest within those boundaries, e.?g., specific habitats of sensitive species.  相似文献   
299.
Hintergrund und ZielEs wird vorgeschlagen, Biomonitoring-Verfahren zu verwenden, um Auswirkungen des Klimawandels auf die belebte Umwelt zu erkennen, zu bewerten und zu dokumentieren, weil ? es mit dieser Methode gelingt, klimainduzierte Veränderungen in besonders empfindlichen Gebieten in Deutschland mit ihren Lebensräumen, Lebensgemeinschaften und Arten darzustellen, ? es bezüglich Zuwanderung und Ausbreitung neuer Schädlinge und Krankheitserreger für Mensch, Tier und Pflanze nach bzw. in Deutschland relevante Informationen liefern kann, ? damit der Politik zur Bewertung der Auswirkungen des Klimawandels wichtige Informationen, Handreichungen und Entscheidungsgrundlagen zur Verfügung gestellt werden können und ? auf dieser Grundlage geeignete Anpassungsmaßnahmen eingeleitet und auf ihre Wirksamkeit geprüft werden können, wie beispielsweise in der Deutschen Anpassungsstrategie (BMU 2009) beschrieben. Für Biomonitoring-Verfahren, die geeignet sind, Auswirkungen des Klimawandels anzuzeigen, wird der Begriff Klima-Biomonitoring vorgeschlagen Diese Verfahren sollten aus verschiedenen Gründen (u.?a. abgestimmte Methodik und gleiche Datenbasis, Kostenersparnis) unter Beteiligung aller Bundesländer umgesetzt werden. Bioindikation ist bereits heute ein unverzichtbares Verfahren, frühzeitig Veränderungen in der belebten Umwelt zu erkennen und somit Hinweise auf besondere Gefahren zu liefern (Frühwarnsystem). Für das Klima-Biomonitoring werden vorzugsweise bestehende Monitoringsysteme mit ihren bereits erhobenen Daten ausgewertet und mitgenutzt. Material und Methoden Das Klima-Biomonitoring greift auf bereits eingeführte und bewährte Methoden der Bioindikation von Umweltveränderungen zurück. Bestehende Methoden werden im Hinblick auf die besonderen, durch den Klimawandel bedingten Anforderungen ergänzt, angepasst und weiterentwickelt. Auf der Grundlage einer Auswertung relevanter laufender Bundes- und Länderprogramme werden wesentliche Wirkungen des Klimawandels identifiziert, die datenliefernden Programme zugeordnet und Auswertungen vorgeschlagen. Zusätzlich werden Datenquellen beschrieben, deren Nutzung weitergehende Betrachtungen ermöglichen. ErgebnisseIn einer Übersichtstabelle werden Monitoring-Programme auf Bundes- und Länderebene systematisiert und hinsichtlich ihrer Bedeutung für die Bewertung von Klimafolgen auf die belebte Umwelt dargestellt. Eine Übersicht über Datenquellen sowie eine Darstellung erster Erkenntnisse aus der Auswertung vorliegender Daten belegen die Relevanz des vorgeschlagenen Verfahrens. Der erkennbare Forschungs- und Entwicklungsbedarf wird umrissen und Vorschläge für eine Optimierung des Daten- und Methodenaustausches benannt. Beispiele zur Anwendung und Vertiefung der Thematik sowie Anregungen zur Weiterentwicklung der Methodik und zum Schließen von Kenntnislücken werden in Folgepublikationen aufgezeigt. DiskussionAuf der Basis des Klima-Biomonitorings kann das Ausmaß der durch den Klimawandel bereits eingetretenen Veränderungen beschrieben sowie Szenarien und Prognosen zu den Auswirkungen von Klimaveränderungen erstellt werden. Weiterhin ist es möglich, die sekundären Wirkungen des Klimawandels, insbesondere die Auswirkungen der Maßnahmen zur Anpassung an den Wandel, mithilfe der Bioindikation auf ihre Wirksamkeit zu prüfen. Für einige Klima-Bioindikatoren ist der kausale Zusammenhang zwischen Klimawandel und Reaktion bereits belegt (zum Beispiel die Frühjahrsphasen in der Pflanzenphänologie), in anderen Fällen müssen noch Methoden zur Unterscheidung zwischen Klimawirkungen und anderen Wirkfaktoren entwickelt werden. Die Erkenntnisse aus dem Klima-Biomonitoring sollen Grundlage für entsprechende Handlungen sein, sodass geeignete Anpassungsstrategien und gleichzeitig Maßnahmen zur Vermeidung oder zur Verminderung der Effekte eingeleitet werden können. Zugleich sollen eine angemessene Politikberatung, eine Information der Öffentlichkeit und die Erfüllung entsprechender Berichtspflichten erfolgen. Schlussfolgerungen:Klima-Biomonitoring ist eine geeignete Methode, um klimainduzierte Veränderungen in besonders empfindlichen Gebieten in Deutschland mit ihren Lebensräumen, Lebensgemeinschaften und Arten darzustellen. Erste Auswertungen zeigen, dass bereits Wirkungen des Klimawandels auf die belebte Umwelt nachweisbar sind. Hierbei liefert die Pflanzenphänologie seit vielen Jahren wertvolle Hintergrunddaten. Eine Verschneidung dieser Hintergrunddaten mit Daten aus anderen geeigneten Monitoring-Programmen und weiteren Informationen (zum Beispiel Geobasisdaten) ermöglicht es, diese Erkenntnisse zu ergänzen. Damit ist die Ermittlung und Bewertung von klimainduzierten Wirkungen auch im Bereich der Ausbreitung von Krankheitsüberträgern und -erregern und anderer Phänomene sowie der Bewertung von Maßnahmen möglich. Empfehlungen und PerspektivenEine abgestimmte Anwendung der Methodik in allen Bundesländern und beim Bund, eine Verbesserung des Daten- und Methodenaustausches, die Identifikation, Erschließung und Nutzung weiterer Datenquellen, die Weiterentwicklung der Methodik und eine Publikation weiterer Erkenntnisse werden empfohlen. Es ist davon auszugehen, dass sich das Klima-Biomonitoring wegen seiner Vorteile als Methode zur Erhebung von Klimafolgen für die belebte Umwelt auch international etablieren wird.  相似文献   
300.
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