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981.
The release of inorganic and organic contaminants from municipal solid waste incinerator (MSWI) bottom ash is controlled to a large extent by the release of dissolved organic carbon (DOC), and in particular by the reactive humic (HA) and fulvic acids (FA) subfractions of DOC. The properties of organic matter contributing to the release of DOC, HA and FA are, therefore, important for environmental risk assessment. In this study we have quantitatively measured the carbon speciation, and its relation with the leaching of Cu, in three fresh and carbonated MSWI bottom ash samples. Results show that up to only 25% of loss on ignition (LOI) consists of organic carbon (OC), while about 17% of OC in the three samples consists of HA and FA. Up to 50% of DOC in MSWI bottom ash leachates was identified as fulvic acid (FA). This value is substantially higher than previously estimated for these MSWI bottom ash samples and is consistent with the higher recovery of the new method that was applied. The results of this study imply that methods focusing on specific carbon fractions are more appropriate for assessment of environmentally relevant organic carbon species than the measurement of LOI. 相似文献
982.
M.C. Carbo J. Boon D. Jansen H.A.J. van Dijk J.W. Dijkstra R.W. van den Brink A.H.M. Verkooijen 《International Journal of Greenhouse Gas Control》2009,3(6):712-719
This paper presents the results of system assessments that were conducted to compare conventional and advanced water–gas shift reactor sections. The latter are specifically tailored for Integrated Gasification Combined Cycles (IGCC) power plants with pre-combustion CO2 capture. The advanced shift reactor section comprises four staged reactors with distributed feeds of synthesis gas and quench water in between the reactors. Conventional shift reactor sections consist of two sequential reactors with intermediate cooling, where the entire synthesis gas stream passes both reactors.The advanced shift reactor section reduces the steam requirement of the water–gas shift reaction up to 70% in comparison with conventional configurations, at carbon dioxide capture ratios of approximately 85%. This reduction allows for lower electric efficiency penalties, thus higher net electric outputs for IGCC power plants with CO2 capture. For each case, the CO2 capture ratio was optimised for the lowest specific lost work per amount of captured CO2. Both the number of reactors and the total catalyst volume are higher for the advanced shift reactor sections, resulting in increased capital expenses. In case of four staged reactors, the additional expenses are expected to be outperformed by the increased revenues associated with the higher net electric output. 相似文献
983.
Halil Ibrahim Inan Valentina Sagris Wim Devos Pavel Milenov Peter van Oosterom Jaap Zevenbergen 《Journal of environmental management》2010,91(12):2440-2454
The Common Agricultural Policy (CAP) of the European Union (EU) has dramatically changed after 1992, and from then on the CAP focused on the management of direct income subsidies instead of production-based subsidies. For this focus, Member States (MS) are expected to establish Integrated Administration and Control System (IACS), including a Land Parcel Identification System (LPIS) as the spatial part of IACS. Different MS have chosen different solutions for their LPIS. Currently, some MS based their IACS/LPIS on data from their Land Administration Systems (LAS), and many others use purpose built special systems for their IACS/LPIS. The issue with these different IACS/LPIS is that they do not have standardized structures; rather, each represents a unique design in each MS, both in the case of LAS based or special systems. In this study, we aim at designing a core data model for those IACS/LPIS based on LAS. For this purpose, we make use of the ongoing standardization initiatives for LAS (Land Administration Domain Model: LADM) and IACS/LPIS (LPIS Core Model: LCM). The data model we propose in this study implies the collaboration between LADM and LCM and includes some extensions. Some basic issues with the collaboration model are discussed within this study: registration of farmers, land use rights and farming limitations, geometry/topology, temporal data management etc. For further explanation of the model structure, sample instance level diagrams illustrating some typical situations are also included. 相似文献
984.
Jasmin Honold Reinhard Beyer Tobia Lakes Elke van der Meer 《Journal of environmental psychology》2012
Urban living environments are known to influence human well-being and health; however, little is known about the multidimensionality of different environmental burdens. The aim of this study is to examine the relations between multiple burdens and self-rated health of city residents in Berlin. A spatial analysis was conducted to determine neighborhood street blocks with high versus low levels of three environmental burdens (traffic noise, air pollution, lack of public green space) as study sites for a cross-sectional household questionnaire. Burden level served as a dichotomous predictor to compare residents' self-reports of neighborhood satisfaction, life satisfaction, health behavior, and psychological and physical health symptoms. Residents from high-burden blocks appraised the environmental conditions more stressful, reported poorer health behavior and were less satisfied with their neighborhood than residents from low-burden blocks. However, they did not differ in regard to more general health symptoms. Three other burdens (behavior-related noise, litter and dirt in public space, lack of urban vegetation), which could not be varied objectively, were assessed by their perceived intensity. Regression analyses of the relations between the perceived levels of all six burdens and outcomes in the total sample revealed the following: Neighborhood satisfaction could be predicted from multiple stressors and resources that co-occur independently, while more general health symptoms were related only to perceived air pollution. The results have implications for both urban planning and public health. 相似文献
985.
We investigated the fledging probability of oystercatcher, Haematopus ostralegus, chicks as a function of hatching order, brood size, territory quality and food availability. Sibling dominance was related
to the hatching order in both low- (’leapfrogs’) and high-quality (’residents’) territories. Differences in hatchling mass
might have aided the establishment of a dominance hierarchy, since breeders produced small late eggs and hatchlings. These
mass differences were most pronounced in leapfrogs, and in large broods in years with lower food availability (’poor’ years).
Late hatchlings fledged less often and with lower body masses compared to early hatchlings in all situations. Leapfrogs produced
smaller broods and hatched their broods more asynchronously in poor years than leapfrogs breeding in years with more available
food (’good’ years) and residents breeding in both poor and good years. Large brood sizes resulted in lower survival of hatchlings
in poor years. These results favour the ’brood reduction’ hypothesis. However, contrary to the expectations of this hypothesis,
hatching order also affected fledging success in residents. Moreover, large brood size resulted in higher survival of hatchlings
in good years, particularly in residents. Thus, although large broods experienced losses due to sibling competition in some
years, they nevertheless consistently produced more fledglings per brood in all years, both as leapfrogs and residents. We
believe this effect is due to parental quality correlating with initial brood size. Most leapfrogs, at best, fledged one chick
successfully each year, losing chicks due to starvation. Nevertheless, leapfrog broods were reduced in size after hatching
significantly less quickly than resident broods. These results suggest that breeders lay and hatch insurance eggs to compensate
for unpredictable losses due to the high predation rates on both nests (ca 50%) and chicks (ca 90%), in accordance with the
’nest failure’ hypothesis.
Received: 14 February 2000 / Revised: 27 September 2000 / Accepted: 10 June 2000 相似文献
986.
Scientific information is not always effectively incorporated into decision-making processes. This phenomenon seems to hold
even when the information is aligned with an articulated need, is generated according to sound scientific procedures, and
is packaged with end-user preferences in mind. We propose that contextual or cultural differences contribute significantly
to the misalignment in communication between those who generate information and those who seek information for improved management
of natural resources. The solution is to cultivate shared understanding, which in turn relies on acknowledgment and sharing
of diverse values and attitudes. This constitutes a difficult challenge in a culturally diverse environment. Whereas cultural
diversity represents wealth in experiences, knowledge and perspectives it can constrain the potential to develop the shared
understandings necessary for effective integration of new information. This article illustrates how a lack of shared understanding
among participants engaged in a resource-management process can produce and perpetuate divergent views of the world, to the
extent that information and knowledge flows are ineffective and scientific information, even when requested, cannot be used
effectively. Four themes were distilled from interviews with management and scientific staff of a natural resource–management
agency in South Africa. The themes are used to illustrate how divergent views embedded in different cultures can discourage
alignment of effort toward a common purpose. The article then presents a sense-making framework to illustrate the potential
for developing shared understandings in a culturally diverse world. 相似文献
987.
Where clocks are redundant: weak circadian mechanisms in reindeer living under polar photic conditions 总被引:1,自引:0,他引:1
Biological rhythms are a result of interplay between endogenous clocks and the ambient light–dark (LD) cycle. Biological timing
in resident polar organisms presents a conundrum because these experience distinct daily LD cycles for only a few weeks each
year. We measured locomotor activity in reindeer, Rangifer tarandus platyrhynchus (SR, n = 5 and 6) and R. tarandus tarandus (NR, n = 6), ranging freely at 78 and 70°N, respectively, continuously throughout 1 year using data loggers. NR, but not SR, are
gregarious which enabled us to examine the integrated effects of differences in social organisation and the photic environment
at two different latitudes on the organisation of activity. In both sub-species, ultradian bouts of activity and inactivity
alternated across the 24-h day throughout the year. This pattern was modified by the LD cycle in NR but barely at all in SR.
Periodogram analysis revealed significant ultradian rhythmicity in both sub-species; the frequency of daily cycles of activity
increased from three per day in winter to nearly five in summer. We conclude that this increase, and a concomitant increase
in the level of daily activity, reflected the seasonal increase in the animals’ appetite and the quality of their forage.
Secondly, the combination, most evident in SR, of a weak photic response, weak circadian mechanisms and a weak social synchronization
reduces the constraints of biological timing in an environment which is effectively non-rhythmic most of the year and permits
expression of the basic ultradian pattern of ruminant activity. Third, the weaker 24-h rhythmicity in SR compared to NR indicates
a latitudinal decrease in circadian organization and photic responsiveness in Rangifer. 相似文献
988.
Fatty extracts of wild birds and fishes were analysed for certain organochlorine insecticides. Nearly all samples contained residues of one or more of the insecticides. 相似文献
989.
After a formerly grazed salt marsh was released from cattle grazing, changes in plant species composition were monitored for
20 yr, using vegetation maps and permanent plots. Three areas, differing in age and nutrient status were compared. The number
of plant species and plant communities decreased.Elymus athericus (Elytrigia pungens) became dominant in most plant communities after 5–20 yr on the oldest and most productive salt marsh. In younger areas it
took more time forE. athericus to become dominant. At least 7 cm of clay seemed to be a prerequisite for this plant species to increase in dominance. The
results from monitoring over decades are discussed in view of the knowledge on succession over centuries as derived from a
chronosequence. 相似文献
990.
Harrie.W.M. van Bommel 《Journal of Cleaner Production》2011,19(8):895-904
This article proposes a new conceptual framework concerning the implementation of sustainability in supply networks from an innovation perspective. Based upon a recent qualitative literature review in environmental, social/ethical and logistics/operations management journals, this article summarizes and analyses the approaches found. Concluded is that even though innovation, socialization, experimental learning and cultural perspectives have been acknowledged as being relevant to explaining supply network dynamics in general, they are rarely included in the current frameworks concerning sustainability. The question still remains why companies influenced by the same external factors and similar in size and power develop a different strategy towards sustainability aspects in their supply network. The article demonstrates with the first results of a survey held in the fashion/clothing sector the relevance of this question.The proposed conceptual framework states that the capability to develop a strategy is influenced by the innovation power of the “focal” company and its supply network. The three implementation strategies presented in the framework are: resign, offensive and defensive. Two propositions are defined to be tested. These propositions focus on the relation between the level of innovation power and the implementation strategy concerning sustainability. Factors used to characterize the innovation power of the “focal” company are: external orientation and transparency, cooperation between departments, learning and adapting, leadership, autonomy and possibility for experimenting, and result driven. Cooperation in the supply networks is characterized by factors like trust, reputation, joint programmes, and cooperative information systems throughout the supply network.In empirical research, strategies found will be related with the level of innovation power. This level will be measured using the factors mentioned. The results might add a new innovation dimension to an improved conceptual framework within the interdisciplinary field of sustainability and supply network research. 相似文献