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161.
Although the (perceived) biodiversity of a natural environment can influence people's actual, or predicted, restorative experiences, little is known about the generality of these effects or the importance of other aspects such as wildlife behaviour. The current research used an experimental approach (with photographs and videos of coastal scenes) to investigate these issues among a large heterogeneous UK sample (n=1,478). On average, coastal settings with higher perceived biodiversity were rated as offering greater restorative potential and were associated with higher willingness-to-visit. Men, and people with lower overall ratings, tended to be more sensitive to biodiversity levels, and older respondents believed coastal settings in general offered more restorative potential. Locations where a species was exhibiting High vs. Low fascination behaviours (e.g. murmurating vs. sleeping) were also rated more positively, highlighting the importance of wildlife behaviour on psychological outcomes, in addition to biodiversity. Implications for conservation and communication are discussed.  相似文献   
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A fundamental procedure is proposed for the identification of liquefaction in saturated soils based on the instability in the material's microstructure. The disturbed state concept (DSC) provides a unified constitutive model for the characterization of entire stress–strain behaviour under cyclic loading, and the values of disturbance at threshold states in the deforming microstructure provides the basis for the identification of liquefaction. The procedure is verified with respect to laboratory behaviour of two sands, saturated Ottawa and Reid Bedford. A mathematical analysis of the DSC constitutive matrix is also performed. Procedures for the application of the DSC for simplified analysis and design, and in finite element procedures are presented. It is believed that the proposed model can provide a fundamental yet simplified procedure for liquefaction analysis, and as a result, it is considered to be an improvement over the available empirical and energy-based procedures. © 1998 John Wiley & Sons, Ltd.  相似文献   
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岩体结构面力学行为的尺寸效应研究   总被引:1,自引:0,他引:1  
尺寸效应是岩体结构面力学行为的重要特征。本文列举了结构面力学行为中普遍存在的尺寸效应现象,并由实测统计资料的分析,论证了结构面力学行为的尺寸效应具有分形结构。通过结构面力学行为尺寸效应的机理研究,建立了结构面力学行为尺寸效应分维数和结构面粗糙度系数尺寸效应分维数之间的相关关系,从而简化了结构面力学行为尺寸效应规律的表述,为客观评价岩体结构面力学参数提供最为有效的手段。  相似文献   
166.
The results from a semi-experimental study of Swedish students’ stated willingness to purchase emission allowances for carbon dioxide are presented. Drawing heavily on recent developments in the literature on integrating norm-motivated behaviour into neoclassical consumer theory, it is assumed that individuals have a preference for maintaining a self-image as a responsible (and thus norm-compliant) person. The results indicate that students’ willingness to purchase carbon allowances is determined by both price and the presence of norms: those who feel personally responsible for contributing to reducing climate damages also appear more inclined to buy allowances. The empirical findings are consistent with the notion that a person's beliefs about others’ stated willingness to purchase carbon allowances imply improvements in their own self-image and ultimately behavioural change. This suggests that information campaigns that attempt to influence beliefs about others’ intentions could promote ‘green’ consumer behaviour in the carbon allowance market. Such (stated) behaviour also appears to be influenced by a person's awareness of the problem of climate change and their beliefs about their own ability to contribute to solving it.

Policy relevance

Although there is a concern that public goods such as reduced climate change may be under-provided in the free market, individual concern for the environment occasionally has profound impacts on consumer choice and voluntary action. This research suggests that information campaigns that attempt to influence beliefs about others’ intentions could promote ‘green’ consumer behaviour in carbon allowance markets. Publicly-provided information about the impacts of climate change and the ways in which these damages stem from individual choices could also induce this type of behaviour.  相似文献   
167.
The Peruvian anchovy or anchoveta (Engraulis ringens) supports the highest worldwide fishery landings and varies in space and time over many scales. Here we present the first comprehensive sub-mesocale study of anchoveta distribution in relation to the environment. During November 2004, we conducted a behavioural ecology survey off central Peru and used a series of observational and sampling tools including SST and CO2 sensors, Niskin bottles, CTD probes, zooplankton sampling, stomach content analysis, echo-sounder, multibeam sonar, and bird observations. The sub-mesoscale survey areas were chosen from mesoscale acoustic surveys. A routine coast-wide (2000 km) acoustic survey performed just after the sub-mesoscale surveys, provided information at an even larger population scale. The availability of nearly concurrent sub-mesoscale, mesoscale and coast-wide information on anchoveta distribution allowed for a unique multi-scale synthesis. At the sub-mesoscale (100s m to km) physical processes (internal waves and frontogenesis) concentrated plankton into patches and determined anchoveta spatial distribution. At the mesoscale (10s km) location relative to the zone of active upwelling (and age of the upwelled water) and the depth of the oxycline had strong impacts on the anchoveta. Finally, over 100s km the size of the productive area, as defined by the upwelled cold coastal waters, was the determining factor. We propose a conceptual view of the relative importance of social behaviour and environmental (biotic and abiotic) processes on the spatial distribution of anchoveta. Our ecological space has two y-axis; one based on self-organization (social behaviour), and the other based on the environmental processes. At scales from the individual (10s cm), to the nucleus (m), social behaviour (e.g. the need to school) drives spatial organization. At scales larger than the school, environmental forces are the main driver of fish distribution. The conceptual ecosystem models presented in this paper may provide the final links needed to develop accurate forecasts of the spatial distribution of anchoveta over multiple scales.  相似文献   
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非线性动力系统理论与地貌学研究   总被引:1,自引:0,他引:1  
郭跃 《地球科学进展》1995,10(6):605-611
非线性动力系统理论及其基本概念迅速地向地貌领域渗透和发展,使得愈来愈多的地貌学家运用NDS的知识结构和思维方式认识地貌现象和地貌发展,许多地貌系统在时空上都显示出非线性或混沌的行为和方式。这些复杂性可能是地貌系统的不平衡、组成的多样和外界环境的变的结果。  相似文献   
170.
Semi‐active dampers offer significant capability to reduce dynamic wind and seismic structural response. A novel resetable device with independent valve control laws that enables semi‐active re‐shaping of the overall structural hysteretic behaviour has been recently developed, and a one‐fifth scale prototype experimentally validated. This research statistically analyses three methods of re‐shaping structural hysteretic dynamics in a performance‐based seismic design context. Displacement, structural force, and total base‐shear response reduction factor spectra are obtained for suites of ground motions from the SAC project. Results indicate that the reduction factors are suite invariant. Resisting all motion adds damping in all four quadrants and showed 40–60% reductions in the structural force and displacement at the cost of a 20–60% increase in total base‐shear. Resisting only motion away from equilibrium adds damping in quadrants 1 and 3, and provides reductions of 20–40%, with a 20–50% increase in total base‐shear. However, only resisting motion towards equilibrium adds damping in quadrants 2 and 4 only, for which the structural responses and total base‐shear are reduced 20–40%. The spectral analysis results are used to create empirical reduction factor equations suitable for use in performance based design methods, creating an avenue for designing these devices into structural applications. Overall, the reductions in both response and base‐shear indicate the potential appeal of this semi‐active hysteresis sculpting approach for seismic retrofit applications—largely due to the reduction of the structural force and overturning demands on the foundation system. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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