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41.
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
42.
43.
Mechanical and Thermal Properties of Bamboo Microfibril Reinforced Polyhydroxybutyrate Biocomposites
R. Krishnaprasad N. R. Veena Hanna J. Maria Rathish Rajan Mikael Skrifvars Kuruvilla Joseph 《Journal of Polymers and the Environment》2009,17(2):109-114
In the present investigation, microfibrils were extracted from raw bamboo and characterized using scanning electron microscope.
Composites based on polyhydroxybutyrate (PHB) and bamboo microfibril were prepared with various microfibril loading. The mechanical
and thermal properties of the resulting composites were measured. Tensile strength and impact strength of the composites were
found to be increasing with increase in the loading of bamboo microfibrils, reached an optimum and thereafter decreased with
further increase in microfibril loading. Percentage crystallinity was found to be increasing with increase in fibril loading.
Thermal stability of the composite was higher than that of pure PHB. The composite could be developed further for various
structural applications. 相似文献
44.
Mikael Hake 《Behavioral ecology and sociobiology》1996,39(2):71-76
Relationships between social status and levels of body reserves stored by members of greenfinch (Carduelis chloris) flocks in winter were investigated. In addition, the adjustment of reserves by birds of different rank to experimental changes
in food predictability and to changed weather conditions were examined. Birds with low social status carried overall larger
body reserves than high-ranked birds. The results of the experiments suggest that this was mainly because subordinates, due
to their low priority to food access, perceived future foraging success as less predictable than dominants. In response to
severe weather, which probably increased the risk of starvation for birds, dominants temporarily increased their reserves
more than subordinates. This response also indicated that birds with low social status carried larger reserves than high-ranked
birds, and demonstrated that dominants could increase food intake when there was a risk of energetic shortfall. The results
suggest that fattening strategies in greenfinches depend on social status. In winter, subordinates may be forced to carry
larger reserves than dominants to safeguard against social constraints in access to food during critical times. As body reserves
may be costly to carry and acquire, this should reduce the probability of surviving the winter for subordinates compared to
dominants.
Received: 2 March 1995/Accepted after revision: 13 April 1996 相似文献
45.
Several ecologically and commercially important fish species spend the winter in a state of minimum feeding activity and at
lower risk of predation. To enable this overwintering behaviour, energetic reserves are generated prior to winter to support
winter metabolism. Maintenance metabolism in fish scales with body size and increases with temperature, and the two factors
together determine a critical threshold size for passive overwintering below which the organism is unlikely to survive without
feeding. This is because the energetic cost of metabolism exceeds maximum energy reserves. In the present study, we estimated
the energetic cost of overwintering from a bioenergetic model. The model was parameterised using respirometry-based measurements
of standard metabolic rate in buried A. tobianus (a close relative to A. marinus) at temperatures from 5.3 to 18.3°C and validated with two independent long-term overwintering experiments. Maximum attainable
energy reserves were estimated from published data on A. marinus in the North Sea. The critical threshold size in terms of length (L
th) for A. marinus in the North Sea was estimated to be 9.5 cm. We then investigated two general predictions: (1) Fish smaller than L
th display winter feeding activity, and (2) size at maturation of iteroparous species is larger than L
th to ensure sufficient energy reserves to accommodate both the metabolic cost of passive overwintering and reproductive investments.
Both predictions were found to be consistent with data on size at maturation and total body energy in December and February. 相似文献
46.
Deconstructing adaptive management: criteria for applications to environmental management. 总被引:4,自引:0,他引:4
The concept of adaptive management has, for many ecologists, become a foundation of effective environmental management for initiatives characterized by high levels of ecological uncertainty. Yet problems associated with its application are legendary, and many of the initiatives promoted as examples of adaptive management appear to lack essential characteristics of the approach. In this paper we propose explicit criteria for helping managers and decision makers to determine the appropriateness of either passive or active adaptive-management strategies as a response to ecological uncertainty in environmental management. Four categories of criteria--dealing with spatial and temporal scale, dimensions of uncertainty, the evaluation of costs and benefits, and institutional and stakeholder support--are defined and applied using hypothetical yet realistic case-study scenarios that illustrate a range of environmental management problems. We conclude that many of the issues facing adaptive management may have less to do with the approach itself than with the indiscriminate choice of contexts within which it is now applied. 相似文献
47.
Juha Sipilä Pertti Auerkari Anna-Mari Heikkilä Risto Tuominen Iris Vela Jyrki Itkonen Mikael Rinne Kalevi Aaltonen 《Journal of Loss Prevention in the Process Industries》2012,25(3):617-622
While the self-heating and spontaneous combustion of coal is a known challenge at coal mines and storage sites, there are known methods for mitigating this challenge for typical open stockpile storage. However, closing the storage will reduce access for corrective action, and it is then important to manage the storage and its transport system with added attention without unduly adding cost or hindering availability. This paper aims to discuss the risk, prevention and extinguishing of fires in closed coal storage facilities, particularly in light of the experience with the Salmisaari underground rock storage facility in Finland. The observed autoignition events have indicated an array of contributing factors, some of which are unique to underground silo storage facilities. On the other hand, many features of the storage facilities can be compared with other extant closed storage systems. The factors affecting fire risk are described and the associated fault and event trees are outlined for autoignition at underground storage. Drawing upon the experiences with past events of self-heating and spontaneous combustion, recommendations are given on cost-effective preventive, corrective and other mitigating action for minimising fire risk and promoting storage availability. 相似文献
48.
Richard L. Andersson Michaela Salajkova Peter E. Mallon Lars A. Berglund Mikael S. Hedenqvist Richard T. Olsson 《Journal of Polymers and the Environment》2012,20(4):967-975
A template transfer method (TTM) and a fiber fixation technique were established for fiber handling and micro tensile stage mounting of aligned and non-aligned electrospun fiber mats. The custom-made template had been precut to be mounted on a variety of collectors, including a rapidly rotating collector used to align the fibers. The method eliminated need for direct physical interaction with the fiber mats before or during the tensile testing since the fiber mats were never directly clamped or removed from the original substrate. By using the TTM it was possible to measure the tensile properties of aligned poly(methyl methacrylate) (PMMA) fiber mats, which showed a 250?% increase in strength and 450?% increase in modulus as compared to a non-aligned system. The method was further evaluated for aligned PMMA fibers reinforced with cellulose (4 wt%) prepared as enzymatically derived nanofibrillated cellulose (NFC). These fibers showed an additional increase of 30?% in both tensile strength and modulus, resulting in a toughness increase of 25?%. The fracture interfaces of the PMMA?CNFC fibers showed a low amount of NFC pull-outs, indicating favorable phase compatibility. The presented fiber handling technique is universal and may be applied where conservative estimates of mechanical properties need to be assessed for very thin fibers. 相似文献
49.
Films of whey protein and chitosan acetic acid salt have lower oxygen permeability than, for example, ethylene-co-vinylalcohol under dry conditions, but water and water vapor seriously impair the gas barrier properties. To reduce the oxygen permeability at 90% relative humidity and the water-vapor transmission rate at 100% relative humidity, the films were coated with an alkyd, a beeswax compound, or a nitrocellulose lacquer. Permeability and transmission rate measurements were performed in accordance with standard methods and showed that the beeswax compound and the nitrocellulose were appropriate as water-vapor barriers. Overall migration to water was measured after 10 days exposure time, with the coated surface exposed to the water, showing that the alkyd-coated and the nitrocellulose-coated films were both below the safety limit for food contact. Water absorbency tests, performed by the Cobb method, showed that the films coated with the beeswax compound or with nitrocellulose lacquer exhibit lower absorbency than the alkyd-coated films. 相似文献
50.
The focus of this article is the Swedish experience of local governance and climate change, including mitigation and adaptation. The municipal response to these two challenges is set within a broader policy context that acknowledges Sweden as a pioneer in environmental governance, including its comparatively high ambitions with regard to the reduction of greenhouse ga emissions. Central-local relations in climate policy are analysed, and climate change mitigation and adaptation are exemplified by some snapshots of municipal initiatives, including the popular habit of networking between municipalities within as well as across national borders. In conclusion we briefly evaluate the Swedish local governance experience of climate change mitigation and adaptation to date as characterized by radical rhetoric and ambitious goals combined with a lot of promising initiatives, although still with fairly modest results in terms of tangible outcomes. Finally, we reflect upon what we consider to be the most important questions for future research on local governance and climate change. 相似文献