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21.
Feng Li Dan Hu Xusheng Liu Rusong Wang Wenrui Yang Juergen Paulussen 《国际发展与全球生态学杂志》2013,20(6):524-533
SUMMARY Rapid urbanisation and serious environmental problems have led people worldwide to realise the significance of urban planning and management towards a sustainable environment. Beijing was used as a case study to develop a framework and strategies for sustainable development using ecological principles. At the regional level, Beijing-Tianjin agglomeration and Hebei Province are considered together. At the Beijing administrative level, some important measures are put forward for revision of the Beijing Urban Master Plan. At the Beijing plain level, the future spatial structure of Beijing city and the relationship between settlements, green space and transportation are considered, and three basic development patterns are proposed. At the inner district level, the ecological corridor system is suggested, based on ecosystem services. At the selected area level, a comprehensive strategy and key measures for conservation and renewal of old Beijing city core are provided. Once strategies for Beijing urban development are implemented step-by-step, a vision for future development can be achieved. This paper provides considerations for improvement of urban planning and management in China and other countries. 相似文献
22.
Gobiid fishes of the genus Gobiodon live in strong association with certain reef-building corals that vary considerably in size and architecture. These fishes hence are excellent model systems for studying evolutionary adaption to specific microhabitats. Using a sample of Gobiodon histrio and G. rivulatus and their most important host corals (Acropora digitifera and A. gemmifera) from the northern Red Sea, we assess (1) how corals that are occupied by gobies differ in their architecture from colonies that are not occupied and (2) how fish body shape is associated with the architecture of their host coral. Fish body shape was assessed by geometric morphometric techniques. Coral measurements included colony size, branch length (BL), and interbranch as well as branch tip distance of adjacent branches, for which we applied a new and non-destructive measurement technique based on casts of two-component epoxy resin. The most important factor influencing the occupation of corals was a BL of more than 5 cm. The distance between coral branches was clearly related to the width of the fishes and hence constrained overall fish size. G. histrio and G. rivulatus differ in adult body shape as well in their allometric development of lateral body compression, resulting in different maximum body sizes attainable in the restricted interbranch space of corals. The strong dependence of coral-associated fishes on large coral colonies with specific architectures increases the extinction risk of fishes within deteriorating coral reefs. 相似文献
23.
Schlumpf M Kypke K Wittassek M Angerer J Mascher H Mascher D Vökt C Birchler M Lichtensteiger W 《Chemosphere》2010,81(10):1171-1183
In order to assess potential risks of exposure to environmental chemicals, more information on concomitant exposure to different chemicals is needed. We present data on chemicals in human milk of a cohort study (2004, 2005, 2006) of 54 mother/child pairs, where for the first time, cosmetic UV filters, synthetic musks, parabens and phthalate metabolites were analyzed in the same sample along with persistent organochlor pollutants (POPs), i.e., organochlor pesticides and metabolites, polybrominated diphenylethers and polychlorinated biphenyls (PCBs). The two groups of chemicals exhibited different exposure patterns. Six out of seven PCB congeners and a majority of pesticides were present in all milk samples, with significant correlations between certain PCB congener and pesticide levels, whereas the cosmetic-derived compounds, UV filters, parabens and synthetic musks, exhibited a more variable exposure pattern with inter-individual differences. UV filters were present in 85.2% of milk samples, in the range of PCB levels. Comparison with a questionnaire revealed a significant correlation between use of products containing UV filters and their presence in milk for two frequently used and detected UV filters, 4-methylbenzylidene camphor and octocrylene, and for the whole group of UV filters. Concentrations of PCBs and organochlor pesticides were within ranges seen in Western and Southern European countries. For several POPs, mean and/or maximum daily intake calculated from individual concentrations was above recent US EPA reference dose values. Our data emphasize the need for analyses of complex mixtures to obtain more information on inter-individual and temporal variability of human exposure to different types of chemicals. 相似文献
24.
Link B Gabrio T Zoellner I Piechotowski I Paepke O Herrmann T Felder-Kennel A Maisner V Schick KH Schrimpf M Schwenk M Wuthe J 《Chemosphere》2005,58(9):1185-1201
In the context of a monitoring program, persistent organic pollutants (POPs) were quantified in the blood of 10 year old children at four different demographic regions in Baden-Wuerttemberg, a highly industrialised federal state in South West Germany. DDE, HCB, PCB 138, PCB 153 and PCB 180 were measured in 1996/1997, 1998/1999, 2000/2001 and 2002/2003 in individual samples of about 400 children per year. PCDD/PCDFs and some relevant coplanar PCBs were determined in pooled samples from children in seven cycles from 1993 to 2003. Blood concentrations of the investigated compounds decreased in that time period by a factor of 2-4 with the exception of most PCDFs. The concentrations of POPs in the blood of the children were distinctly lower than the concentrations reported for adults. Breast feeding was associated with about 30% higher median concentrations of DDE, HCB, PCBs and a 30% increase for mean PCDD/PCDF concentrations. Concerning demographic differences, significant lower concentrations of HCB, PCBs and PCDD/PCDFs could be seen in children from Mannheim compared to the region of Aulendorf. About 10-20% higher concentrations were found in boys compared to girls for HCB, indicator PCBs and PCDD/PCDFs. The pattern of non-ortho and mono-ortho PCBs in the blood of children was similar to the pattern reported for mother's milk, and PCB 126 and PCB 156 contributed about 70% to the toxicity of dioxin-like PCBs and about one-third to total TEQ including PCDD/PCDFs. 相似文献
25.
Anja Soboll Michael Elbers Roland Barthel Juergen Schmude Andreas Ernst Ralf Ziller 《Mitigation and Adaptation Strategies for Global Change》2011,16(4):477-498
Within climate change impact research, the consideration of socioeconomic processes remains a challenge. Socioeconomic systems
must be equipped to react and adapt to global change. However, any reasonable development or assessment of sustainable adaptation
strategies requires a comprehensive consideration of human-environment interactions. This requirement can be met through multi-agent
simulation, as demonstrated in the interdisciplinary project GLOWA-Danube (GLObal change of the WAter Cycle; ). GLOWA-Danube has developed an integrated decision support tool for water and land use management in the Upper Danube catchment
(parts of Germany and Austria, 77,000 km2). The scientific disciplines invoked in the project have implemented sixteen natural and social science models, which are
embedded in the simulation framework DANUBIA. Within DANUBIA, a multi-agent simulation approach is used to represent relevant
socioeconomic processes. The structure and results of three of these multi-agent models, WaterSupply, Household and Tourism,
are presented in this paper. A main focus of the paper is on the development of global change scenarios (climate and society)
and their application to the presented models. The results of different simulation runs demonstrate the potential of multi-agent
models to represent feedbacks between different water users and the environment. Moreover, the interactive usage of the framework
allows to define and vary scenario assumptions so as to assess the impact of potential interventions. It is shown that integrated
modelling and scenario design not only provide valuable information, but also offer a platform for discussing complex human-environment-interactions
with stakeholders. 相似文献
26.
27.
The anthropocentric term “extremophile” was introduced more than 30 years ago to describe any organism capable of living and
growing under extreme conditions—i.e., particularly hostile to human and to the majority of the known microorganisms as far
as temperature, pH, and salinity parameters are concerned. With the further development of studies on microbial ecology and
taxonomy, more “extreme” environments were found and more extremophiles were described. Today, many different extremophiles
have been isolated from habitats characterized by hydrostatic pressure, aridity, radiations, elevated temperatures, extreme
pH values, high salt concentrations, and high solvent/metal concentrations, and it is well documented that these microorganisms
are capable of thriving under extreme conditions better than any other organism living on Earth. Extremophiles have also been
investigated as far as the search for life in other planets is concerned and even to evaluate the hypothesis that life on
Earth came originally from space. Extremophiles are interesting for basic and applied sciences. Particularly fascinating are
their structural and physiological features allowing them to stand extremely selective environmental conditions. These properties
are often due to specific biomolecules (DNA, lipids, enzymes, osmolites, etc.) that have been studied for years as novel sources
for biotechnological applications. In some cases (DNA polymerase, thermostable enzymes), the search was successful and the
final application was achieved, but certainly further exploitations are next to come. 相似文献
28.
Degradation of Cellulose Acetate-Based Materials: A Review 总被引:1,自引:0,他引:1
Juergen Puls Steven A. Wilson Dirk Hölter 《Journal of Polymers and the Environment》2011,19(1):152-165
Cellulose acetate polymer is used to make a variety of consumer products including textiles, plastic films, and cigarette
filters. A review of degradation mechanisms, and the possible approaches to diminish the environmental persistence of these
materials, will clarify the current and potential degradation rates of these products after disposal. Various studies have
been conducted on the biodegradability of cellulose acetate, but no review has been compiled which includes biological, chemical,
and photo chemical degradation mechanisms. Cellulose acetate is prepared by acetylating cellulose, the most abundant natural
polymer. Cellulose is readily biodegraded by organisms that utilize cellulase enzymes, but due to the additional acetyl groups
cellulose acetate requires the presence of esterases for the first step in biodegradation. Once partial deacetylation has
been accomplished either by enzymes, or by partial chemical hydrolysis, the polymer’s cellulose backbone is readily biodegraded.
Cellulose acetate is photo chemically degraded by UV wavelengths shorter than 280 nm, but has limited photo degradability
in sunlight due to the lack of chromophores for absorbing ultraviolet light. Photo degradability can be significantly enhanced
by the addition of titanium dioxide, which is used as a whitening agent in many consumer products. Photo degradation with
TiO2 causes surface pitting, thus increasing a material’s surface area which enhances biodegradation. The combination of both
photo and biodegradation allows a synergy that enhances the overall degradation rate. The physical design of a consumer product
can also facilitate enhanced degradation rate, since rates are highly influenced by the exposure to environmental conditions.
The patent literature contains an abundance of ideas for designing consumer products that are less persistent in the outdoors
environment, and this review will include insights into enhanced degradability designs. 相似文献
29.
Solvent extracts of HOM isolated from highly polluted sediments from the Ravenna Lagoon were studied. Diagnostic indicators included polycyclic aromatic hydrocarbons (PAHs) and nonylphenols as hazardous organic pollutants to characterize anthropogenic pollution, as well as fatty acids (FA, analysed as methyl esters, FAME) to characterize microbial communities responsible for natural attenuation processes. The distribution of PAHs including cyclopentafused surrogates pointed to a significant pyrogenic origin, characteristic for methane combustion. The PAH distribution was characterized by high concentrations of highly carcinogenic analytes with molecular weights of 276Da (benzo[ghi]perylene prevailing) and 300Da (coronene prevailing). The PAH pattern as obtained by solvent extraction was very different from that obtained from pyrolysis/thermochemolysis of the HOM polymeric matrix. The FA pattern indicated strong bacterial input, with a significant contribution from methanotrophic bacteria as revealed by monounsaturated members with n:1omega8 and n:1omega5 double bonds in the alkyl chain. Terrestrial inputs as revealed by FAME analysis beyond C(20) with pronounced even-over-odd discrimination were of minor significance. This was confirmed by the pattern of nC(24)-nC(30) alcohols in strong even-over-odd prevalence occurring in relatively low concentrations. The hopane hydrocarbon distribution reflected a distinctive impact from industrial processes utilizing heavy fractions of petroleum as feedstock. Hopanols along with the 17beta(H),21beta(H)-bishomohopanoic acid pointed to hopane producers, including methanotrophic and sulfate-reducing bacteria. Nonylphenols, which could not be detected in the pyrograms of solvent-extracted HOM matrix, had a total concentration of about 70microg g(-1) referred to the HOM in the solvent extract. In addition to common phytosterols including beta-sitosterol, coprostanol could be detected in the solvent extracts pointing to human fecal matter contamination. Concentration of resin acids turned out to be very low, thus no harmful environmental effects are to be expected from these compounds. 相似文献
30.
Humic acid (HA) isolated from highly polluted sediment from the Ravenna Lagoon (Italy) was subjected to pyrolysis/tetramethylammonium hydroxide (TMAH)-induced thermochemolysis to reveal the impact of industrial activities on humification. Special effort was made to distinguish between analytes originating from the polymeric humic organic matter network along with sequestered compounds (which cannot be released by solvent extraction), and the solvent-extractable lipid fraction sorbed onto the organic matrix. Exhaustive solvent extraction of the isolated HA proved mandatory to avoid biased results when identifying the origin of the pyrolyzates of untreated samples. Conventional pyrolysis at 750 degrees C of the "degreased" HA revealed a characteristic polycyclic aromatic hydrocarbon (PAH) pattern, which was significantly different than patterns obtained from the pyrolysis of natural humic acids. TMAH-induced thermochemolysis at 500 degrees C provided information on carboxylic acids covalently bound inside the HA network via ester bonds. Thermochemolysis of the "degreased" matrix at 750 degrees C, resulting in the cleavage of C-O and C-C bonds, revealed a significant PAH pattern very similar to that obtained by conventional pyrolysis. The uncommon PAH pattern points to the formation of bound residues as the humification/detoxification pathway. Recalcitrant hopane hydrocarbons showed very similar patterns for both the untreated and exhaustively solvent-extracted samples, which points to hopanes being linked inside the humic network via C-C bonds. The technique of non-discriminating flash pyrolysis used in this study, based on extremely rapid capacitive discharge heating in a Silcosteel capillary, proved to be an excellent method to obtain high-boiling pyrolyzates (PAHs beyond 252Da molecular weight, C(29)-C(31)-hopanes). 相似文献