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151.
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Jung, Yong and Minha Choi, 2012. Survey‐Based Approach for Hydrological Vulnerability Indicators Due to Climate Change: Case Study of Small‐Scale Rivers. Journal of the American Water Resources Association (JAWRA) 48(2): 256‐265. DOI: 10.1111/j.1752‐1688.2011.00608.x Abstract: The vulnerability indicators can be used to develop water resource policy in the context of climate change. The Delphi method, an interactive prediction technique, is an efficient way to apply weighting functionality to vulnerability indicators consisting of three parts: Exposure, Sensitivity, and Adaptive Capacity on climate change. The Delphi method is an anonymous iterative survey of expert opinion, which is then shared with other participants. A total of three different rounds were carried out. The first round was a problem selection set, and the second and third were the standard Delphi survey. Fifty‐eight experts (66% academic and 34% practitioner) were invited. The rates of reply were 59, 50, and 38% for the first, second, and third Delphi processes, respectively. The degree of consensus of the Delphi survey was validated via variance changes and Kendall’s W test. Exposure and Adaptive Capacity presented increased levels of agreement among respondents in their given priorities. Particularly strong convergence (0.20 to 0.71 in Kendall’s W) of the experts’ opinions for Adaptive Capacity was observed. The results of this study indicate that finalized factors with ultimate weights through the Delphi method can be a strong support for governmental policy making with respect to climate change.  相似文献   
153.
Regional Environmental Change - A shift to organic farming in the agricultural sector is a process of building a new system where on the one hand, agro-innovations are generated and on the other,...  相似文献   
154.
Journal of Material Cycles and Waste Management - Maize straw- and rice husk-derived biochars were produced in a simple metal kiln without automated control. Their characteristics and effects on...  相似文献   
155.
Freshwater cladocera such as Daphnia magna and Ceriodaphnia dubia have been used extensively for freshwater toxicity test worldwide. However, these species may not be indigenous in certain geographical regions, which restrict the utility of these organisms as test species. In the present study, we investigated optimal culture and test conditions for an indigenous freshwater macroinvertebrate of Korea, Moina macrocopa. The culture conditions that were evaluated included water temperature (20°C and 25°C), rearing media (moderately hard water or MHW, with or without selenium supplementation, or Elendt M4), and food density (2.5 × 107 and 5 × 107 cells/mL of Selenastrum capricornutum), and their effects on the life history characteristics of M. macrocopa were determined. Population growth rate of M. macrocopa was maximized at 25°C with 5 × 107 cells/mL of algal food density in MHW. A series of chronic three brood reference toxicant tests were conducted under the ideal culture conditions that were identified here, and the results of the tests indicated reliable reproducibility of the test protocol. Optimal culture and test conditions that were identified for M. macrocopa in the present study are suggested for evaluation of chronic toxicity of chemicals and industrial or municipal discharge.  相似文献   
156.
The present study used commercial feeds, food waste feeds, Napier grass, and mixed feeds (food waste feed to Napier grass ratio, 1:10) to feed grass carp (Ctenopharyngodon idellus). The results indicated that grass carp fed with food waste feeds and mix feeds achieved growth performance (based on specific growth rate and feed conversion ratio) that was similar to commercial feeds (p?>?0.05). Concentrations of metalloid/metals in food waste feeds and polycyclic aromatic hydrocarbons (PAHs) in Napier grass were relatively higher than other types of fish feeds (p?<?0.05). However, most of the metalloid/metals and PAH levels in fish fed with four types of fish feeds were not significantly different (p?>?0.05). These findings show that food waste feeds are suitable for using in the production of fish feed and Napier grass can be served as supplemental feeds for grass carp, and hence reducing the production cost.  相似文献   
157.
Environmental Science and Pollution Research - Nitrogen oxide (NOx) emissions in fuel from the stationary as well as from mobile sources primarily from power stations, industrial heaters,...  相似文献   
158.
Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change. Accumulating evidence suggests that exposure to bioaerosols may cause adverse health effects, including severe disease. Studies of bioaerosols have primarily focused on their chemical composition and largely neglected their biological composition and the negative effects of biological composition on ecosystems and human health. Here, current molecular methods for the identification, quantification, and distribution of bioaerosol agents are reviewed. Modern developments in environmental microbiology technology would be favorable in elucidation of microbial temporal and spatial distribution in the atmosphere at high resolution. In addition, these provide additional supports for growing evidence that microbial diversity or composition in the bioaerosol is an indispensable environmental aspect linking with public health.  相似文献   
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The marine dinoflagellate Cochlodinium polykrikoides is a harmful and highly motile algal species. To distinguish between the motility characteristics of solitary and chain-forming cells, the swimming trajectories and speeds of solitary cells and 2- to 8-cell chains of C. polykrikoides were measured using a digital holographic particle tracking velocimetry (PTV) technique. C. polykrikoides cells exhibited helical swimming trajectories similar to other dinoflagellate species. The swimming speed increased as the number of cells in the chain increased, from an average of 391 μm s−1 (solitary cells) to 856 μm s−1 (8-cell chain). The helix radius R and pitch P also increased as the number of cells in the chain increased. R increased from 9.24 μm (solitary cell) to 20.3 μm (8-cell chain) and P increased from 107 μm (solitary cell) to 164 μm (8-cell chain). The free thrust-generating motion of the transverse flagella and large drag reduction in the chain-forming cells seemed to increase the swimming speed compared to solitary cells. The measured swimming speeds agreed with those from field observations. The superior motility of chain-forming C. polykrikoides cells may be an important factor for its bloom, in addition to the factors reported previously.  相似文献   
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