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931.
This study describes the development of the Perceived Restorative Characteristics Questionnaire (PRCQ), a measure of perceived restorative characteristics of zoo attractions. The questionnaire was administered in two zoo attractions. The hypothesized five factor structure of the PRCQ, and relations between perceived restorative characteristics and experienced pleasure in and preference for the attractions were examined. In Study 1, 137 visitors of a Dutch zoo evaluated perceived restorative characteristics of a butterfly garden; In Study 2, 158 visitors evaluated those of a baboon attraction. In Study 1 three factors emerged (fascination, escape and coherence); In Study 2 four factors could be distinguished (fascination, novelty, escape, coherence). Compatibility did not appear as a separate factoring either study. Perceived fascination and escape were significant predictors of experienced pleasure and preference in both attractions. The implications of the findings are discussed. 相似文献
932.
The karst disturbance index (KDI) consists of 31 environmental indicators contained within the five broad categories: geomorphology, hydrology, atmosphere, biota, and cultural. The purpose of this research is to apply the KDI to two distinct karst areas, west Florida, USA, and Apulia, Italy. Through its application, the utility of the index can be validated and other important comparisons can be made, such as differences in the karst legislations implemented in each region and the effect of time exposure to human occupation to each karst terrain. Humans have intensively impacted the karst of southeast Italy for thousands of years compared to only decades in west-central Florida. However, west-central Florida's higher population density allows the region to reach disturbance levels comparable to those reached over a longer period in Apulia. Similarly, Italian karst is more diverse than the karst found in west-central Florida, creating an opportunity to test all the KDI indicators. Overall, major disturbances for southeast Italy karst include quarrying, stone clearing, and the dumping of refuse into caves, while west-central Florida suffers most from the infilling of sinkholes, soil compaction, changes in the water table, and vegetation removal. The application of the KDI allows a benchmark of disturbance to be established and later revisited to determine the changing state of human impact for a region. The highlighting of certain indicators that recorded high levels of disturbance also allows regional planners to allocate resources in a more refined manner. 相似文献
933.
Summary The parasitic wasp Nesolynx albiclavus maintains a very skewed offspring sex ratio (ca. 4% males). We studied proximate, causal factors of the son-daughter choice mechanism to obtain insight into the precision of the procedures and the underlying rules. We analyzed the number of males in clutches produced during sessions of 12 or 24 h. The results show that the timing of the next male egg depends on the time elapsed and the number of eggs laid since the previous one. The influence of the passage of time per se during non-laying periods was reduced in an experiment with 4-h periods. The data show that the first male egg is produced by a fairly rigid process: about the sixth egg in a run will be left unfertilized. No further male egg will appear in the next 10–20 eggs if they are laid in rapid succession. 相似文献
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936.
Joop van der Pligt Joop van der Linden Peter Ester 《Journal of environmental psychology》1982,2(3):221-231
Attitudinal differences regarding the use of nuclear energy were investigated. Results obtained in a random sample drawn from the population of four communities in The Netherlands within 30 miles of a nuclear power plant showed a strong relationship between subjects' attitudes towards nuclear energy and their perceptions of the possible consequences of nuclear energy. ‘Pro’- and ‘con’-subjects showed marked differences in the importance attached to the different possible consequences and their endorsement of the salience of more general social issues. Results provide support for the view that individuals perceive a false consensus with respect to the relative prevalence of similar attitudes among other people. Finally, subjects' perceptions of others with similar or opposing attitudes towards the issue of nuclear energy showed marked differences in evaluation especially for the extreme attitude groups. 相似文献
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939.
W. R. van Wijk 《Die Naturwissenschaften》1931,19(44):894-895
940.
Mapping of exceedances of ozone critical levels for crops and forest trees in The Netherlands: Preliminary results 总被引:1,自引:0,他引:1
Within the framework of the UN-ECE Convention on Long-Range Transboundary Air Pollution (CLRTAP) critical levels of ozone for forest trees and crops have been determined. In this paper procedures are presented for constructing maps of The Netherlands showing measured ozone concentrations for comparison with the critical levels. The critical ozone levels for forest trees and crops are exceeded widely and frequently in The Netherlands. The frequency and size of exceedances depend on meteorological conditions: during a hot, sunny summer like 1989 or 1990 exceedances of the critical levels by a factor of two or three were observed in the whole of The Netherlands; in a cold, rainy summer like 1991 or 1993 only minor exceedances were observed in some parts (mainly in the south) of the country. 相似文献