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The two studies reported further test reversal theory hypotheses concerning human psychological responses to different types of settings and environmental events on an Asian sample. In study 1, individuals in four settings representing different combinations of metamotivational state and arousal level (telic and paratelic/low arousal; telic and paratelic/high arousal) completed the telic state measure (TSM; Svebak & Murgatroyd, 1985). Significant differences between participants' mean scores across the four settings were obtained for TSM items serious–playful, planning–spontaneous, felt arousal, preferred arousal, effort and arousal discrepancy. In study 2 different environmental events in the same setting (changes in reading tasks), used in a crossover design, were used to induce reversals in individuals' operative metamotivational states. The results obtained from TSM scores pretask 1, between tasks and posttask 2. indicated significant time-of-testing interaction effects on the TSM serious–playful, planning–spontaneous and effort items. In addition, a main effect for TSM felt arousal was found. These results showed that reversals in metamotivational states were induced by the environmental event and that felt arousal scores increased across the three administrations of the TSM.  相似文献   
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Sustainable development of the earth's limited water and land resources is of paramount importance because of rising world population and existing conflicting demands for these resources. Enormous capital investment has been made in developing these resources, but now there is irrefutable evidence that such developments have led to major resource degradation. This includes problems of salinisation and damages to ecosystems. The countries predominantly affected by human induced salinisation are located in arid and semi-arid regions of the world and include Australia, China, Egypt, India, Pakistan, USSR, and USA. This paper describes the processes of salinisation, its impacts and the use of quantitative methods in salinity investigation and management. Australia is used as a case study of typical salinity problems and as a demonstration of the fruitful application of quantitative methods. The paper concludes that quantitative methods such as surface water and groundwater models are powerful design, management and predictive tools in salinity investigation. However, application of some models, such as those for unsaturated flow and transport and groundwater solute transport, are not widespread due to uncertainties in describing the complexity of the processes and the lack of hydrodispersive data.  相似文献   
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Classification and distribution of mangrove vegetation are vital information for the proper development of a mangrove management plan. In this study, classification for the mangroves of the district of Kemaman were done using both 1 : 5000 aerial photographs and Landsat TM imageries. The coverage by aerial photographs is limited to the coastal and estuarine areas only. Thus, for areas further upstream of the aerial photo coverage, Landsat TM imageries were used. Analysis of aerial photographs and remote sensing images revealed that the mangroves of Kemaman could be classified into 14 different classes of vegetation. All the 14 classes were identified from areas covered by the aerial photographs. For areas covered by the Landsat images only 7 classes of vegetation were identified. The accuracy for aerial photograph and Landsat images are 91.2% and 87.8%, respectively. It can be concluded that although both techniques are useful in determining the mangrove vegetation classes, the large 1 : 5000 aerial photographs are more accurate and provided more detailed information comparatively.  相似文献   
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Assessment of environmental changes in the Orinoco River delta   总被引:1,自引:0,他引:1  
Major anthropogenic driven changes in the hydrologic and sedimentation patterns of the Orinoco River have had an impact on environmental conditions in the delta. The abrupt water flow reduction from 3,600 to 200 m3 s–1 in one of its major distributaries resulting from dam construction forced its transformation from a fresh-water body into a tidal channel with an increase in salinity level (as far as 100 km upstream) and with well-mixed water at the mouth and estuarine connection to the Paria Gulf. Three different sectors along this distributary can be identified (indicated by the Na/Cl ratio in the water). As a result, noticeable changes have occurred in the mangrove community which moved about 60 km further upstream. The changes have also promoted the formation of new islands of sediment progradation at the mouth of this distributary, where successional colonization and species replacement by different species of grasses and mangroves take place. Electronic Publication  相似文献   
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Pyrite ash is created as waste from the roasting of pyrite ores during the production of sulphuric acid. These processes generate great amounts of pyrite ash waste that is generally land filled. This creates serious environmental pollution due to the release of acids and toxic substances. Pyrite ash waste can be utilized in the iron production industry as a blast furnace feed to process this waste and prevent environmental pollution. The essential parameters affecting the pelletization process of pyrite ash were studied using bentonite as a binder. Experiments were then carried out using bentonite and a mixture of bentonite with calcium hydroxide and calcium chloride in order to make the bentonite more effective. The metallurgical properties of pyrite ash, bentonite, calcium hydroxide, calcium chloride, a mixture of these and sintered pellets were studied using X-ray analysis. The crushing strength tests were carried out to investigate the strength of pyrite ash waste pellets. The results of these analyses showed that pyrite ash can be agglomerated to pellets and used in the iron production industry as a blast furnace feed. The crushing strength of the pellets containing calcium hydroxide and calcium chloride in addition to bentonite was better than the strength of pellets prepared using only bentonite binder.  相似文献   
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