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191.
To categorize the marine environmental health status, the Oslo and Paris commissions have recently formulated Ecological Quality Objectives (EcoQOs) for many ecological features including the contamination of coastal bird eggs with mercury and organochlorines. In this study, we describe spatial and temporal patterns of egg contamination around the North Sea and compared them to the EcoQOs. Concentrations of mercury, polychlorinated biphenyl (??PCB) congeners, dichlorodiphenyltrichloroethane (??DDT) and derivatives, hexachlorobenzene (HCB) and hexachlorocyclohexane (??HCH) isomers were analysed in two tern species (Sterna hirundo and Sterna paradisaea) and Oystercatcher (Haematopus ostralegus) eggs collected between 2008 and 2010 in a total of 21 sites in seven countries surrounding the North Sea. Hg, ??PCB and HCB were highest in the southern sites, while ??DDT and ??HCH concentrations were greatest in eggs from the western North Sea and the Elbe estuary. There were rarely any consistent decreases over time for any compounds. In the terns, Hg, HCB and ??HCH increased at most sites, ??PCB and ??DDT in Sweden and Norway. In the Oystercatcher, HCB and ??HCH increased at more than the half of the sites, ??PCB, ??DDT and Hg at several German sites. In the terns, Hg, ??PCB and ??DDT exceeded the EcoQO in all, HCB in most years and sites. At most sites, ??HCH fulfilled the EcoQO in some study years. In the Oystercatcher, Hg, ??PCB and ??DDT exceeded the EcoQO in all or most years and sites. HCB and ??HCH fulfilled the EcoQO in some or all years at most sites. The EcoQO was exceeded most frequently in estuaries. We conclude that EcoQOs are suitable for drawing contamination patterns of the coastal North Sea in an easily understandable manner, offering the opportunity to harmonize the EcoQOs with coordinated environmental monitoring programmes.  相似文献   
192.
Art has long been an important force in environmental movements. In China, environmental art is a fast-growing sector of the art scene. This new area of emphasis is expanding the function of art and aiding in China’s environmental movement by challenging both imported Western practices and Maoist era philosophy, thereby opening up new ways of considering the relationship between human “progress,” political systems, economic practices, and their repercussions on existing ecosystems. I turn to artist Xu Xiaoyan’s paintings to explore how the notion of “progress” can be challenged through art. I use Deleuze and Guattari’s theory of deterritorialization and reterritorialization to map how Xu’s art offers viewers space to think outside dominant paradigms, creates the potential for changes in human consciousness, considers the environment as a composition of relationships and interactions, and provokes discussion concerning the impact of linear notions of time on human conceptions of nature.  相似文献   
193.
We present direct evidence of the release of synthetic nanoparticles from urban applications into the aquatic environment. We investigated TiO2 particles as these particles are used in large quantities in exterior paints as whitening pigments and are to some extent also present in the nano-size range.TiO2 particles were traced from exterior facade paints to the discharge into surface waters. We used a centrifugation based sample preparation which recovers TiO2 particles between roughly 20 and 300 nm. Analytical electron microscopy revealed that TiO2 particles are detached from new and aged facade paints by natural weather conditions and are then transported by facade runoff and are discharged into natural, receiving waters. Microscopic investigations are confirmed by bulk chemical analysis. By combining results from microscopic investigations with bulk chemical analysis we calculated the number densities of synthetic TiO2 particles in the runoff.  相似文献   
194.
The aim of this study was to improve the removal of heavy metals from sewage sludge ash by a thermochemical process. The resulting detoxified ash was intended for use as a raw material rich in phosphorus (P) for inorganic fertiliser production. The thermochemical treatment was performed in a rotary kiln where the evaporation of relevant heavy metals was enhanced by additives. The four variables investigated for process optimisation were treatment temperature, type of additive (KCl, MgCl(2)) and its amount, as well as type of reactor (directly or indirectly heated rotary kiln). The removal rates of Cd, Cr, Cu, Ni, Pb, Zn and of Ca, P and Cl were investigated. The best overall removal efficiency for Cd, Cu, Pb and Zn could be found for the indirectly heated system. The type of additive was critical, since MgCl(2) favours Zn- over Cu-removal, while KCl acts conversely. The use of MgCl(2) caused less particle abrasion from the pellets in the kiln than KCl. In the case of the additive KCl, liquid KCl - temporarily formed in the pellets - acted as a barrier to heavy metal evaporation as long as treatment temperatures were not sufficiently high to enhance its reaction or evaporation.  相似文献   
195.
The main objective of this study was to investigate possible temporal trends of persistent organic pollutants (POPs) and mercury in eggs of herring gulls (Larus argentatus), black-legged kittiwakes (Rissa tridactyla), common guillemots (Uria aalge) and Atlantic puffins (Fratercula arctica) in Northern Norway. Eggs were collected in 1983, 1993 and 2003. Egg concentrations of POPs (PCB congeners IUPAC numbers: CB-28, 74, 66, 101, 99, 110, 149, 118, 153, 105, 141, 138, 187, 128, 156, 157, 180, 170, 194, 206, HCB, alpha-HCH, beta-HCH, gamma-HCH, oxychlordane, trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT) and mercury were quantified. Generally, POP levels decreased between 1983 and 2003 in all species. No significant temporal trend in mercury levels was found between 1983 and 2003.  相似文献   
196.
An emission inventory was compiled for heavy metal air emissions from road transport in Europe (EU-40). For the database, country-specific data was taken such as the diesel and gasoline fuel consumption per country, the content of Pb in gasoline and diesel fuel and the share of different vehicle types. For tyre and brake wear emissions, average wear rates and heavy metal contents of different materials were used to develop emission factors for tyre and brake wear. It covers exhaust emissions (Pb from gasoline and diesel) as well as non-exhaust emissions (As, Cd, Cr, Ni and Pb from the wear of brake linings and vehicle tyres). The base year is 2000, and two scenarios were developed for 2010, a business as usual (BAU) scenario and a maximum feasible technical reduction (MFTR) scenario. Both result in a remarkable decrease in Pb exhaust emissions and a rising share of non-exhaust emissions. To assess the results, the inventory is (a) compared to an inventory compiled with a top-down approach that covers the same area and years but only emissions from combustion processes and (b) added to an inventory covering all sectors for heavy metal air emissions.  相似文献   
197.
Background, Aim and Scope Modelling of the fate of environmental chemicals can be done by relatively simple multi-media box models or using complex atmospheric transport models. It was the aim of this work to compare the results obtained for both types of models using a small set of non-ionic and non-polar or moderately polar organic chemicals, known to be distributed over long distances. Materials and Methods Predictions of multimedia exposure models of different types, namely three multimedia mass-balance box models (MBMs), two in the steady state and one in the non-steady state mode, and one non-steady state multicompartment chemistry-atmospheric transport model (MCTM), are compared for the first time. The models used are SimpleBox, Chemrange, the MPI-MBM and the MPI-MCTM. The target parameters addressed are compartmental distributions (i.e. mass fractions in the compartments), overall environmental residence time (i.e. overall persistence and eventually including other final sinks, such as loss to the deep sea) and a measure for the long-range transport potential. These are derived for atrazine, benz-[a]-pyrene, DDT, α and γ-hexachlorocyclohexane, methyl parathion and various modes of substance entry into the model world. Results and Discussion Compartmental distributions in steady state were compared. Steady state needed 2–10 years to be established in the MCTM. The highest fraction of the substances in air is predicted by the MCTM. Accordingly, the other models predict longer substance persistence in most cases. The results suggest that temperature affects the compartmental distribution more in the box models, while it is only one among many climate factors acting in the transport model. The representation of final sinks in the models, e.g. burial in the sediment, is key for model-based compartmental distribution and persistence predictions. There is a tendency of MBMs to overestimate substance sinks in air and to underestimate atmospheric transport velocity as a consequence of the neglection of the temporal and spatial variabilities of these parameters. Therefore, the long-range transport potential in air derived from MCTM simulations exceeds the one from Chemrange in most cases and least for substances which undergo slow degradation in air. Conclusions and Perspectives MBMs should be improved such as to ascertain that the significance of the atmosphere for the multicompartmental cycling is not systematically underestimated. Both types of models should be improved such as to cover degradation in air in the particle-bound state and transport via ocean currents. A detailed understanding of the deviations observed in this work and elsewhere should be gained and multimedia fate box models could then be ‘tuned in’ to match better the results of comprehensive multicompartmental transport models. ESS-Submission Editor: Prof. Dr. Michael Matthies (matthies@uos.de)  相似文献   
198.
We studied the echolocation and foraging behavior of two Neotropical frugivorous leaf-nosed bats (Carollia perspicillata, C. castanea: Phyllostomidae) in a flight cage. To test which cues Carollia uses to detect, identify, and localize ripe Piper fruit, their preferred natural food, we conducted experiments under semi-natural conditions with ripe, unripe, and artifical fruits. We first offered the bats ripe fruits and documented their foraging behavior using multiflash stereophotography combined with simultaneous sound recordings. Both species showed a similar, stereotyped foraging pattern. In searchflight, the bats circled through the flight cage in search of a branch with ripe fruit. After finding such a branch, the bats switched to approach behavior, consisting of multiple exploration flights and the final approach when the bats picked up the fruit at its tip and tore it off in flight. Our behavioral experiments revealed that odor plays an important role in enabling Carollia to find ripe fruit. While foraging, Carollia always echolocated and produced multiharmonic, frequency-modulated (FM) signals of broad bandwidth, high frequency, short duration, and low intensity. We discriminated an orientation phase (mostly a single pulse per wingbeat) and an approach phase (groups of two to six pulses per wing beat). We conclude from the bats' behavioral reaction to real and artificial fruit as well as from characteristic patterns in their echolocation behavior that during exploration flights, Carollia changes from primarily odor-oriented detection and initial localization of ripe fruit to a primarily echo-oriented final localization of the position of the fruit. Received: 27 March 1997 / Accepted after revision: 28 February 1998  相似文献   
199.
This paper reviews the information on trends of past emissions of mercury, lead, and cadmium in Europe, as well as examines current levels and future scenarios of these emissions. The impact of various factors on emission changes is discussed including the implementation of various strategies of emission controls in Europe. Future emissions are forecasted on the basis of various scenarios of economy growth in Europe, implementation of European and global legislation (e.g. the Kyoto agreement), population changes, etc.Changes of emissions of mercury, lead, and cadmium are then related to the changes of concentrations of these contaminants in air and precipitation samples at selected stations in Europe. It can be concluded that the reduction trends of anthropogenic emissions of cadmium and lead in Europe are similar to the reduction trends of air concentrations of these metals during the last 2 decades. Somewhat different relationship has been noted for changes in emissions and precipitation. In general for Europe, 60% reduction of Cd emissions was met by about 45% reductions of Cd concentrations in precipitation at the studied stations during the last 2 decades.There is a potential for further reduction of these emissions until the year 2010 up to about 37% for Cd, 51% for Pb, and 49% for Hg as estimated within various emission scenarios presented in the paper.  相似文献   
200.
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