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41.
Among the effects of global warming, sea level rise (SLR) and severe typhoons pose the greatest threat to the stability of human settlements along coastlines. Therefore, countermeasures must be developed to mitigate the influences of strong typhoons and persistent SLR for coastal protection. This study assesses climate change impacts on coastal erosion, especially in two projected SLR scenarios of RCP2.6 and RCP8.5. The results show that SLR and severe typhoons lead to the increase of coastal erosion, beach lowering and scour. Moreover, as in projected SLR scenarios, average waves in high tide can cause severe soil erosion at inner slopes and lead to dyke failure by 2060. The paper highlights the need for additional countermeasures to protect the coast of Hai Hau district against SLR and severe typhoons. Among the alternatives available for countering these threats, applying soil stabilization and soil improvement combined with geosynthetics are promising strategies for coastal structures. Hybrid structures can be used with earth reinforcement and soil improvement. Additionally, the paper emphasizes the importance of multiple protective adaptations, including geosynthetics and ecological engineering measures against climate change-induced severe erosion on the coast of Hai Hau district.  相似文献   
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Radon mass exhalation rate of soil samples was measured using an exhalation chamber of 10 dm(3) volume and a Lucas cell. The results show that mass of sample, grain size and water content influence the radon mass exhalation rate. For soil of (226)Ra activity concentration about 2500 Bq kg(-1) and samples within the range from 0.20 kg to 0.50 kg, the radon mass exhalation rate values are higher than those for samples of other masses. The observed radon exhalation rate is an inverse function of the average grain size. At the water content about 6% by weight, the radon mass exhalation rate reaches maximum, then it decreases with both increasing and decreasing of the water content in the sample.  相似文献   
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Die Kenntnis biochemischer Veränderungen von lipophilen körperfremden Stoffen ist hinsichtlich deren Elimination aus dem Organismus, sowie bei Überlegungen zur Voraussage toxischer, insbesondere carcinogener Wirkungen von vorrangiger Bedeutung  相似文献   
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The dynamic coastline of Soc Trang Province in the Mekong Delta of Viet Nam is in most parts protected from erosion, storms and flooding by a narrow belt of mangroves. However, the unsustainable use of natural resources and development in the coastal zone is threatening the protection function of this forest belt. This situation is exacerbated by the impacts of climate change, particularly by the increased intensity and frequency of storms, floods and by rising sea levels. Based on analysis of past experience of mangrove planting and historical changes in mangrove cover, an integrated and site-specific approach to adaptation to climate change has been put in place, which comprises mangrove planting and rehabilitation with emphasis on resilience to climate change, and participatory involvement of local communities in effective mangrove management and protection through co-management. To address uncertainties associated with the impacts of climate change, testing of new mangrove planting techniques has started. This includes mimicking successful natural regeneration for small-scale planting in sites with high wave energy and transformation of existing even-aged plantations into more diverse forests—both in terms of structure and species composition. The pre-requisite for mangrove rehabilitation in erosion sites has successfully been put in place: breakwaters made from bamboo have reduced erosion and stimulated sedimentation. The design and construction of the wave-breaking structures, which was based on a numerical model which simulates hydrodynamics and shoreline development, ensures that downdrift erosion can be avoided as far as possible. A comprehensive monitoring program has been established and initial results provide evidence for the effectiveness of the bamboo breakwaters. Early experience shows that co-management is an effective way of maintaining and enhancing the protection function of the mangrove forest belt and at the same time providing livelihood for local communities. Payment for ecosystem services contributes to sustainability of co-management as well as livelihood improvement.  相似文献   
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When animals have to decide where to forage, what to eat or with whom to mate, they can base their decisions on either socially or personally acquired information. In accordance with theoretical predictions, there is experimental evidence that animals adjust the weight they give to both sources of information depending on circumstances. Notably, several studies have demonstrated that individuals rely more on social information when personal information is difficult to acquire or unreliable, because these conditions leave them uncertain as how to behave. Yet, even when individuals are exposed to the same conditions, they generally differ widely in the value they attribute to social and personal information. These differences suggest that the tendency to rely on social information would also depend on intrinsic characteristics that affect, for instance, individual efficiency in collecting personal information. To address this issue, we conducted laboratory experiments using female zebra finches (Taeniopygia guttata) and we tested them under three consecutive conditions. First, we evaluated their reliance on social information in a mating context and in a foraging context. Then, we measured their efficiency in acquiring personal information by recording their sampling behaviour when searching for hidden food. We found that females that sampled their environment less actively consistently relied on social information to a greater extent compared with those that invested more in sampling. Contrary to what is generally assumed, then, our study demonstrates that social information use is not entirely flexible and context dependent.  相似文献   
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Food and Environmental Virology - Hydroponic production of vegetables is becoming more common, especially in regions with unfavorable climate for year-round crop production. However, if viruses are...  相似文献   
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Environmental Science and Pollution Research - Combined effects of global warming and rapid urbanization replace green spaces with urban facilities. Children in urban areas are at a higher risk of...  相似文献   
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This study investigated the level of norovirus contamination in oysters collected at a lagoon receiving urban drainage from Hue City for 17 months (August 2015–December 2016). We also investigated the genetic diversity of norovirus GI and GII in oyster and wastewater samples by using pyrosequencing to evaluate the effect of urban drainage on norovirus contamination of oysters. A total of 34 oyster samples were collected at two sampling sites (stations A and B) in a lagoon. Norovirus GI was more frequently detected than GII (positive rate 79 vs. 41%). Maximum concentrations of GI and GII were 2.4 × 105 and 2.3 × 104 copies/g, respectively. Co-contamination with GI and GII was observed in 35% of samples. Norovirus GII concentration was higher at station A in the flood season than in the dry season (P = 0.04, Wilcoxon signed-rank test). Six genotypes (GI.2, GI.3, GI.5, GII.2, GII.3, and GII.4) were identified in both wastewater and oyster samples, and genetically similar or identical sequences were obtained from the two types of samples. These observations suggest that urban drainage and seasonal flooding contribute to norovirus contamination of oysters in the study area.  相似文献   
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