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111.
In Africa, the land and water resources quality are key factors for sustainable development. The degradation of the quality of these resources leads to scarcities and conflicts, which together threaten the sustainability of rural livelihoods. This work investigated and analysed the livelihoods conflicts over the land and water resources and their scarcities, policies that contributed to the land and water scarcities and the livelihood conflicts and linkage of the conflicts to the resources scarcities and degradation. Implications of degradation of the resources, development policies and livelihoods conflicts on sustainable development are discussed. Literature study, visits and discussions, participatory assessments, observations and questionnaire survey were used tools to collect data. Interviews of the 266 households revealed that, those experiencing the land and water scarcities and conflicts over these resources are significantly (p < 0.001) higher than those not experiencing the scarcities and conflicts. Crop-livestock competition, over the land and water resources causes prominent conflicts. A significant, (p < 0.05) associations of livelihoods conflicts to water shortage and period of water shortage for crop and livestock production were found. Improved accessibility to soil and water management technologies, wildlife–livestock co-existence, recognition of needs and land rights for pastoralists are recommended to minimize scarcities and herders versus farmers’ conflicts.  相似文献   
112.
Three years of hourly atmospheric radon measurements at Sado Island (Japan) are discussed and compared with corresponding measurements at Gosan (South Korea), and Hok Tsui (China). In conjunction with back trajectory analysis, Sado radon data are used to characterise the seasonal variability in fetch regions of air masses subject to extremes of terrestrial influence. In winter, fetch regions of air masses that have experienced the greatest terrestrial influence covered southern Siberia; in summer, the terrestrial fetch was dominated by Japan; throughout the remaining months the terrestrial fetch encompassed the Korean Peninsula and far eastern China. Summer radon data are then used to estimate the radon flux from central Honshu (23.5 mBq m?2 s?1), which varied regionally between 10.6 and 47.9 mBq m?2 s?1. The Sado radon record reported here completes a 4-site, multi-year dataset of hourly radon concentrations across East Asia and the central Pacific (spanning 16° of latitude), which constitutes a unique evaluation tool for transport and mixing schemes of atmospheric and chemical transport models.  相似文献   
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Cyrtarachne is an orb-weaving spider belonging to the subfamily Cyrtarachninae (Araneidae) which includes triangular-web-building Pasilobus and bolas spiders. The Cyrtarachninae is a group of spiders specialized in catching moths, which is thought to have evolved from ordinary orb-weaving araneids. Although the web-building time of nocturnal spiders is in general related to the time of sunset, anecdotal evidence has suggested variability of web-building time in Cyrtarachne and its closely related genera. This study has examined the effects of temperature, humidity, moonlight intensity, and prey (moths) availability on web-building time of Cyrtarachne bufo, Cyrtarachne akirai, and Cyrtarachne nagasakiensis. Generalized linear mixed model (GLMM) have revealed that humidity, and not prey availability, was the essential variable that explained the daily variability of web-building time. Experiments measuring thread stickiness under different humidities showed that, although the thread of Cyrtarachne was found to have strong stickiness under high humidity, low humidity caused a marked decrease of thread stickiness. By contrast, no obvious change in stickiness was seen in an ordinary orb-weaving spider, Larinia argiopiformis. These findings suggest that Cyrtarachne adjusts its web-building time to favorable conditions of high humidity maintaining strong stickiness, which enables the threads to work efficiently for capturing prey.  相似文献   
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During the World Summit on Sustainable Development (WSSD), it was agreed that adequate chemical management based on risk assessment should be achieved by 2020. To achieve the WSSD goals, it is important to evaluate and enhance the voluntary activities of corporations because they are the main agents dealing with chemical management. To this end, we developed new evaluation indicators that were combined with the SCP Axes (Science Axis - evaluation of the scientific basis; Capacity Axis - evaluation of the abilities of personnel and organizations; and the Performance Axis - evaluation of results of activities and information disclosure to the community, etc.) and 4 elements (hazard assessment, exposure assessment, risk assessment, and risk management). We administered surveys to Japanese corporations from 2006 to 2008 to verify the developed indicators. The survey results showed that the activities concerning chemical management were very different across corporations for each industry category and that the hazard assessment improved, reflecting a vigorous social movement that included legal obligations. Therefore, the new evaluation indicators possessed high resolution and precisely grasped the changes in corporate activities. We found that these indicators provided an effective way to understand corporate activities designed to meet the goals of the WSSD.  相似文献   
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Environmental Science and Pollution Research - Formaldehyde (HCHO) is a naturally occurring compound found in ambient air which can induce cancer and sick-building syndrome. It plays an important...  相似文献   
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Journal of Material Cycles and Waste Management - Open burning is a waste management practice performed by many people worldwide, especially in developing countries. Lack of detailed data of open...  相似文献   
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Journal of Material Cycles and Waste Management - Since to 1990,&nbsp;Urbanization has occurred due to an increase in the number of unpredicted citizens and migration from the countryside to...  相似文献   
120.
Journal of Polymers and the Environment - Rheological analysis using multiple frequencies and different temperatures and X-ray analysis were performed on previously synthesized paramylon acetate...  相似文献   
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