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121.
Would somebody be more willing to start recycling if they knew that their friends were all recycling? Social influence refers to the ways in which our behaviour is affected by what other people do, or by what other people think. Various insights from theories of social influence have been applied as part of interventions to encourage resource conservation, such as the use of social norms, social learning, and social comparison processes. The question arises: Is social influence as effective as is sometimes assumed? This review compares the effectiveness of different social influence approaches to encourage resource conservation via a meta-analysis and outlines what remains to be learned about the mechanisms linking social influence to behaviour change. A random-effects meta-analysis with a sample of 29 studies revealed that social influence approaches were effective when compared to a control group. They were also more effective when compared to another intervention, although in this case the effect size was small. The effectiveness was different for different social influence approaches and for different target groups. These findings raise a number of important questions, which form the basis of a research agenda for better understanding the processes through which social influence approaches encourage resource conservation. 相似文献
122.
This article analyses lay understandings of climate change elicited through a longitudinal population-based survey of climate change, place and community among 1162 residents in the Hunter Valley, Southeast Australia. We explore how older residents in contrasting rural and coastal geographic areas perceive climate change information in terms of culturally relevant meanings and values, lived experiences and emotional responses to seasonal cycles, temperature fluctuations and altered landscapes. Thematic analysis of comments given by 467 interviewees to an open-ended question identified a significant subset for whom the concepts of “nature” and “science” express competing views about changing climatic conditions. For them, the idea of “natural cycles” is a significant cultural construct that links nature and humans through time in a way that structures stable and resilient understandings of environmental change, drawing on established cosmological frameworks for contemplating the future in relation to the past. In contrast to other studies that postulate scepticism and denial as individuals’ fear management strategies in the face of climate change threat, we found that the natural cycles view is founded on a reassuring deeper conviction about how nature works, and is linked to other pro-environmental values not commonly found in sceptical groups. It is a paradox of natural cycles thinking that it rejects the anthropocentrism that is at the heart of science-based environmentalism. By contrast, it places humans as deeply integrated with nature, rather than operating outside it and attempting with uncertain science to control something that is ultimately uncontrollable. 相似文献
123.
Detrital zircon provenance studies that combine low‐temperature fission‐track and high‐temperature U–Pb single‐grain age dating are powerful in constraining sediment provenance by documenting the tectonothermal evolution of the sediment source(s). We apply these techniques to Miocene (12–6 Ma) sandstones of the Hengchun Peninsula, southern Taiwan, which, based on diametrically opposite palaeocurrents, have a controversial provenance. U–Pb grain ages range from the Miocene (8 Ma) to Archaean (2.5 Ga). Cretaceous thermal cooling is recorded by detrital zircon fission tracks at Loshui and Lilongshan. Permian fission‐track grain ages account for <33% of zircon ages from Loshui, while at Lilongshan, Jurassic/Triassic grain ages account for 33–66% of all zircon fission‐track ages. Minor (<12%) Miocene age components are detected in both formations. These new data suggest that the primary sources of these Miocene sediments were similar. A simple model is proposed invoking sediment reworking in this complex tectonic setting. Terra Nova, 00, 000–000, 2010 相似文献
124.
Defining and detecting undesirable disturbance in the context of marine eutrophication 总被引:1,自引:0,他引:1
Tett P Gowen R Mills D Fernandes T Gilpin L Huxham M Kennington K Read P Service M Wilkinson M Malcolm S 《Marine pollution bulletin》2007,55(1-6):282-297
An understanding of undesirable disturbance to the balance of organisms is needed to diagnose marine eutrophication as defined by EU Directives and OSPAR. This review summarizes the findings of the UK Defra-funded Undesirable Disturbance Study Team, which concluded that 'an undesirable disturbance is a perturbation of a marine ecosystem that appreciably degrades the health or threatens the sustainable human use of that ecosystem'. A methodology is proposed for detecting disturbance of temperate salt-water communities dominated by phytoplanktonic or phytobenthic primary producers. It relies on monitoring indicators of ecosystem structure and vigour, which are components of health. Undesirable disturbance can be diagnosed by accumulating evidence of ecohydrodynamic type-specific changes in: (i) bulk indicators; (ii) frequency statistics; (iii) flux measurements; (iv) structural indicators; and (v) indicator species. These are exemplified by (i) chlorophyll, transparency, dissolved oxygen, and opportunistic seaweed cover; (ii) HABs frequency; (iii) primary production; (iv) benthic and planktonic 'trophic indices'; (v) seagrasses and Nephrops norvegicus. Ecological Quality Objectives are proposed for some of these. Linking the diagnosis to eutrophication requires correlation of changes with nutrient enrichment. The methodology, which requires the development of a plankton community index and emphasizes the importance of primary production as an indicator of vigour, can be harmonized with the EU Water Framework Directive and OSPAR's Strategy to Combat Eutrophication. 相似文献
125.
Joint pollen and oxygen isotope data from Ocean Drilling Program Site 1234 in the southeast Pacific provide the first, continuous record of temperate South American vegetation and climate from the last 140 ka. Located at 36°S, 65 km offshore of Concepcion, Chile, Site 1234 monitors the climatic transition zone between northern semi-arid, summer dry-winter wet climate and southern year-round, rainy, cool temperate climate. Dominance of onshore winds suggests that pollen preserved here reflects transport to the ocean via rivers that drain the region and integrate conditions from the coastal mountains to the Andean foothills. Down-hole changes in diagnostic pollen assemblages from xeric lowland deciduous forest (characterized by grasses, herbs, ferns, and trees such as deciduous beech, Nothofagus obliqua), mesic Valdivian Evergreen Forest (including conifers such as the endangered Prumnopitys andina), and Subantarctic Evergreen Rainforest (comprised primarily of southern beech, N. dombeyi) reveal large rapid shifts that likely reflect latitudinal movements in atmospheric circulation and storm tracks associated with the southern westerly winds. During glacial intervals (MIS 2-4, and 6), rainforests and parkland dominated by Nothofagus moved northward into the region. At the MIS 6/5e transition, coeval with the rapid shift to lower isotopic values, rainforest vegetation was rapidly replaced by xeric plant communities associated with Mediterranean-type climate. An increased prominence of halophytic vegetation suggests that MIS 5e was more arid and possibly warmer than MIS 1. Although rainforest pollen rises again at the end of MIS 5e, lowland deciduous forest pollen persists through MIS 5d and 5c, into MIS 5b. Substantial millennial-scale variations occur in both interglacial and glacial regimes, attesting to the sensitivity of the southern westerly belt to climate change. Comparison of the cool, mesic N. dombeyi rainforest assemblage from Site 1234 with δ18O in the Byrd Ice core shows that on time scales longer than 10 ka, cool-moist conditions in central Chile were coherent with and occurred in phase with Antarctic cooling. This is also likely at millennial scales, although rainforest pollen lags Antarctic cooling with exponential response times of about 1000 years, which plausibly reflects the ecological response time to regional climate change. 相似文献
126.
127.
David Yates Hector Galbraith D. Purkey A. Huber-Lee J. Sieber J. West S. Herrod-Julius B. Joyce 《Climatic change》2008,91(3-4):335-350
The Chinook salmon (Oncorhynchus tshawytscha) spawns and rears in the cold, freshwater rivers and tributaries of California’s Central Valley, with four separate seasonal runs including fall and late-fall runs, a winter run, and a spring run. Dams and reservoirs have blocked access to most of the Chinook’s ancestral spawning areas in the upper reaches and tributaries. Consequently, the fish rely on the mainstem of the Sacramento River for spawning habitat. Future climatic warming could lead to alterations of the river’s temperature regime, which could further reduce the already fragmented Chinook habitat. Specifically, increased water temperatures could result in spawning and rearing temperature exceedences, thereby jeopardizing productivity, particularly in drought years. Paradoxically, water management plays a key role in potential adaptation options by maintaining spawning and rearing habitat now and in the future, as reservoirs such as Shasta provide a cold water supply that will be increasingly needed to counter the effects of climate change. Results suggest that the available cold pool behind Shasta could be maintained throughout the summer assuming median projections of mid-21st century warming of 2°C, but the maintenance of the cold pool with warming on the order of 4°C could be very challenging. The winter and spring runs are shown to be most at risk because of the timing of their reproduction. 相似文献
128.
Joyce Schmatz Marc Holland Steffen Giese Wouter van der Zee Janos. L. Urai 《Journal of the Geological Society of India》2010,75(1):74-88
The aim of this study is to improve our knowledge of the processes that lead to clay smear during faulting of a layered sand-clay
sequence in an analogue sandbox model. We carefully characterized mechanical properties of the materials used by a series
of geotechnical tests. Displacement field was quantified using PIV (Particle Image Velocimetry). The model is water-saturated
to allow the deformation of wet clay and sand in one experiment comprising a sand package with a horizontal layer of clay
above a predefined rigid basement fault. The thickness and rigidity of the clay layer are the parameters varied in this study.
The model shows a range of structures that are related to competence contrast between sand and different clay types. Results
show ductile shearing of soft clay with a transition to brittle fracturing of stiff clay accompanied by the formation of rotating
clay blocks in the fault zone. Localized deformation is observed through time showing (i) the propagation of one active fault
migrating laterally through the sediment package, and (ii) the formation of a stable prism between two or more active faults
that gets progressively smaller with minor rotation of the hanging wall fault. Continuous clay smear is observed resulting
from the lateral injection of clay as well as from a reworked mixture of sand and clay. 相似文献
129.
Alberto Flandes Linda Spilker Stuart Pilorz Nicolas Altobelli Scott G. Edgington 《Planetary and Space Science》2010,58(13):1758-1765
Early ground-based and spacecraft observations suggested that the temperature of Saturn's main rings (A, B and C) varied with the solar elevation angle, B′. Data from the composite infrared spectrometer (CIRS) on board Cassini, which has been in orbit around Saturn for more than five years, confirm this variation and have been used to derive the temperature of the main rings from a wide variety of geometries while B′ varied from near −24° to 0° (Saturn's equinox).Still, an unresolved issue in fully explaining this variation relates to how the ring particles are organized and whether even a simple mono-layer or multi-layer approximation describes this best. We present a set of temperature data of the main rings of Saturn that cover the ∼23°—range of B′ angles obtained with CIRS at low (α∼30°) and high (α≥120°) phase angles. We focus on particular regions of each ring with a radial extent on their lit and unlit sides. In this broad range of B′, the data show that the A, B and C rings’ temperatures vary as much as 29-38, 22-34 and 18-23 K, respectively. Interestingly the unlit sides of the rings show important temperature variations with the decrease of B′ as well. We introduce a simple analytical model based on the well known Froidevaux monolayer approximation and use the ring particles’ albedo as the only free parameter in order to fit and analyze this data and estimate the ring particle's albedo. The model considers that every particle of the ring behaves as a black body and warms up due to the direct energy coming from the Sun as well as the solar energy reflected from the atmosphere of Saturn and on its neighboring particles. Two types of shadowing functions are used. One analytical that is used in the latter model in the case of the three rings and another, numerical, that is applied in the case of the C ring alone. The model lit side albedo values at low phase are 0.59, 0.50 and 0.35-0.38 for the A, B and C rings, respectively. 相似文献
130.