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81.
82.
可持续消费与生产第八次国际高级研讨会 全世界面临着贫穷、饥饿、疾病和环境恶化等不断发展的问题.行动指令(最新指令是世界可持续发展峰会的<执行计划>以及联合国千年目标)已经到位.我们政府、企业和民间团体已经承诺改变现实.我们现在的挑战就是我们前进的速度.我们必须更快地开展工作,因为人类的生命和地球的健康正面临险境.在未来两天里我希望你们讨论并确定具体而实际的工作范畴--项目、举措、合作--,以便带来根本性的变化,建立供其他人适应、准备和效仿的模式.中心内容就是执行. 相似文献
83.
In many animal species, male and female interests often differ when it comes to decisions over mating and fertilization. However, it is intrinsically difficult to determine the degree to which males and females exert control over the various processes that determine the outcome of reproductive interactions, and thus to predict how such conflicts will be resolved. For example, in species where sperm are transferred to females via a spermatophore or other external sperm packaging device, it is unclear which sex determines subsequent sperm transfer dynamics to the female reproductive tract. To address this question, we used a reciprocal cross experimental design in a bushcricket species (Poecilimon veluchianus) comprising two subspecies differing in the dynamics of sperm transfer. The reciprocal crosses show that in these bushcrickets the timing of sperm transfer in inter-subspecies crosses closely resemble those typical of the subspecies of the male partner, indicating that it is the properties of the spermatophore rather than its handling by the female that determine sperm transfer dynamics. There was neither a significant female influence nor any indication of an interaction between males and females with regard to the number of sperm transferred after a set interval. Our study suggests that males rather than females appear to control the timing of the insemination process in this species. 相似文献
84.
Sander Van Den Burg 《Local Environment》2013,18(4):367-381
This paper studies the emergence of one particular ‘new’ environmental policy instrument: disclosure of emission and pollution data. Disclosure is part of a relatively new sub‐set of regulatory measures, based on monitoring, transparency, citizen‐empowerment and accountability. It originated in the United States but has recently attracted international attention. The attractiveness of disclosure is obvious; it promises environmental improvement combined with strengthened environmental democracy and community empowerment. By analysing the experiences in the US, and the developments in the Netherlands, this paper seeks to assess the functioning and effectiveness of disclosure. The available empirical evidence suggests that disclosure has a positive impact on the environmental performance of industrial facilities as well as a democratising effect. It is argued that Dutch policy makers wrongfully assume that disclosure cannot work in the Netherlands. The consequence is that citizens are provided with little specific information that cannot be used to put pressure on polluters. 相似文献
85.
Ben Drake James C. R. Smart Mette Termansen Klaus Hubacek 《Regional Environmental Change》2013,13(3):649-659
Many regulating ecosystem services exhibit non-excludability and non-rivalry characteristics akin to public goods. This makes it unlikely that such regulating ecosystem services will attract a price in the marketplace. Policymakers, therefore, find difficulties in determining a correct economic valuation for regulating ecosystem services, with potentially severe consequences for aligning policy for ecosystem service provision with public preferences for service delivery. This research used a choice modelling approach to estimate public preferences for delivery of two regulating ecosystem services; reductions in the flood risk to the British city of York (implemented by filling in drainage ditches in peat moorland further up the catchment), and a reduction in CO2 emissions (implemented by planting Poplar trees for biomass either locally in the study area or elsewhere in the UK). The choice experiment presented respondents with options providing different levels of CO2 reduction, implemented locally or nationally, and different levels of flood risk reduction, at a range of different prices, with a tax as the payment vehicle. Subsequent analysis with latent class (LC) models showed considerable heterogeneity of preference among respondents, particularly with regard to the location of tree planting for CO2 reduction. One LC segment showed a significant preference for achieving a high level CO2 reduction through national, as opposed to local tree planting, potentially indicating the existence of NIMBYism. The same LC segment displayed a preference for moderate reductions in the flood risk to York, even though this would deliver no personal benefit for a substantial proportion of the segment. This could, therefore, indicate altruistic behaviour towards geographically proximate beneficiaries. 相似文献
86.
Lignin is a main component of plant litter. Its degradation is thought to be critical for litter decomposition rates and the build-up of soil organic matter. We studied the relationships between lignin degradation and the production of dissolved organic carbon (DOC) and of CO2 during litter decomposition. Needle or leaf litter of five species (Norway spruce, Scots pine, mountain ash, European beech, sycamore maple) and of different decomposition stage (freshly fallen and up to 27 months of field exposure) was incubated in the laboratory for two years. Lignin degradation was followed with the CuO method. Strong lignin degradation occurred during the first 200 incubation days, as revealed by decreasing yields of lignin-derived phenols. Thereafter lignin degradation leveled off. This pattern was similar for fresh and decomposed litter, and it stands in contrast to the common view of limited lignin degradation in fresh litter. Dissolved organic carbon and CO2 also peaked in the first period of the incubation but were not interrelated. In the later phase of incubation, CO2 production was positively correlated with DOC amounts, suggesting that bioavailable, soluble compounds became a limiting factor for CO2 production. Lignin degradation occurred only when CO2 production was high, and not limited by bioavailable carbon. Thus carbon availability was the most important control on lignin degradation. In turn, lignin degradation could not explain differences in DOC and CO2 production over the study period. Our results challenge the traditional view regarding the fate and role of lignin during litter decomposition. Lignin degradation is controlled by the availability of easily decomposable carbon sources. Consequently, it occurs particularly in the initial phase of litter decomposition and is hampered at later stages if easily decomposable resources decline. 相似文献
87.
Philipp Balzer Klaus Peter Rippe Peter Schaber 《Journal of Agricultural and Environmental Ethics》2000,13(1-2):7-27
The 1992 incorporation of an article by referendum in the Swiss Constitution mandating that the federal government issue regulations
on the use of genetic material that take into account the dignity of nonhuman organism raises philosophical questions about
how we should understand what is meant by “the dignity of nonhuman animals,” and about what sort of moral demands arise from
recognizing this dignity with respect to their genetic engineering. The first step in determining what is meant is to clarify
the difference between dignity when applied to humans and when applied to nonhumans. Several conceptions of human dignity
should be rejected in favor of a fourth conception: the right not to be degraded. This right implies that those who have it
have the cognitive capacities that are prerequisite for self-respect. In the case of nonhuman organisms that lack this capacity,
respecting their dignity requires the recognition that their inherent value, which is tied to their abilities to pursue their
own good, be respected. This value is not absolute, as it is in the case of humans, so it does not prohibit breeding manipulations
that make organisms more useful to humans. But it does restrict morally how sentient animals can be used. In regard to genetic
engineering, this conception requires that animals be allowed the uninhibited development of species specific functions, a
position shared by Holland and Attfield, as opposed to the Original Purpose conception proposed by Fox and the Integrity of
the Genetic Make-up position proposed by Rolston. The inherent value conception of dignity, as here defended, is what is meant
in the Swiss Constitution article.
This paper is a slightly revised version of a paper that had been published in German in 1998 (“Menschenwürde vs. Würde der
Kreatur,” Freiburg i.Br.). 相似文献
88.
Benzyl-penicillin (Penicillin G) transformation in aqueous solution at low temperature under controlled laboratory conditions 总被引:1,自引:0,他引:1
Antibiotics are released into the environment in a variety of ways: via wastewater effluent as a result of incomplete metabolism in the body after use in human therapy, as runoff after use in agriculture, through improper disposal by private households or hospitals or through insufficient removal by water treatment plants. Unlike in most European countries, in Arctic regions effluents are not suitably treated prior to their release into the aquatic environment. Also, many of the scattered human settlements in remote regions of the Arctic do not possess sewage treatment facilities and pharmaceutical residues therefore enter the aqueous environment untreated. Only limited data are available on the biodegradation of antibiotics under Arctic conditions. However, such information is needed to estimate the potential harm of antibiotics for the environment. Pen-G is used in this study since it is a widely prescribed antibiotic compound whose environmental properties have not yet been investigated in detail. Thus, for a very first assessment, the OECD approved biodegradation Zahn-Wellens test (ZWT, OECD 302 B) was used to study biodegradation and non-biotic elimination of the antibiotic Benzyl-penicillin (Pen-G) at different temperatures (5°C, 12.5°C and 20°C). The testing period was extended from the OECD standard of 28-42d. In addition to dissolved organic carbon (DOC), Pen-G levels and major transformation products were recorded continuously by LC-ion-trap-MS/MS. DOC monitoring revealed considerable temperature dependence for the degradation process of Pen-G. DOC loss was slowest at 5°C and considerably faster at 12.5°C and 20°C. In the initial step of degradation it was found that Pen-G was hydrolyzed. This hydrolyzed Pen-G was subsequently further degraded by decarboxylation, the result of which was 2-(5,5-dimethyl-1,3-thiazolidin-2-yl)-2-(2-phenylacetamido)acetic acid. Furthermore, direct elimination of 2-phenyl-acetaldehyde from the hydrolyzed and decarboxylated Pen-G also led to the formation of 2-[amino(carboxy)methyl]-5,5-dimethyl-1,3-thiazolidone-4-carboxylic acid. Since biodegradation slows down considerably at a low temperature, the resulting transformation products had considerably longer residence times at 5°C compared to higher temperature conditions within the 42-d experiment. The results presented here clearly demonstrate that a risk assessment for pharmaceuticals present in low ambient temperature environments (i.e. the Arctic) cannot be based on test results obtained under standard laboratory conditions (i.e. 20°C ambient temperatures). 相似文献
89.
Götz R Bauer OH Friesel P Herrmann T Jantzen E Kutzke M Lauer R Paepke O Roch K Rohweder U Schwartz R Sievers S Stachel B 《Chemosphere》2007,67(3):592-603
Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and other organic micropollutants were determined in dated sediment/soil cores collected from the flood-plain of the river Elbe near Pevestorf (PT), approximately 125 km upstream of Hamburg, and Heuckenlock (HL) in southeast of Hamburg. Concentrations of PCDD/Fs peaked sharply at PT in the 1950s and at HL at the end of the 1940s. Cluster analyses provide evidence that the region of Bitterfeld-Wolfen (about 350-400 km upstream of Hamburg) could be the source of the PCDD/F contamination existing in the cores PT and HL since the 1940s. Obviously it is caused by sediments of the river Elbe of a similar composition. Whereas the PCDD/Fs, HCHs (hexacyclohexane isomers), DDX (DDT, DDD, DDE), and tetrachlorinated ethers in PT and HL presumably originated predominantly from the Bitterfeld-Wolfen region, organotin compounds in HL and dichlorinated haloethers in HL during the 1940s and 1950s can probably largely be attributed to emissions from the Hamburg region. Although they are separated by a large distance, in both sediment cores PT and HL concentrations and composition patterns of most organic micropollutants analyzed widely match. Inductively it can be concluded that similar contaminations will be found in many of the river bank soils between the Bitterfeld-Wolfen region and Hamburg. Excavation of top soils may uncover highly contaminated materials. Since the dated sediment cores show the variation in contaminants in the Elbe sediments over a defined time period, it is possible to make an approximate assessment of the actual degree of contamination to be expected in areas where in previous decades contaminated dredged sediments from the Elbe and from the Port of Hamburg have been deposited on land and used for building plots or for agricultural purposes. 相似文献
90.