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661.
Xuan Bien Do 《Disasters》2020,44(3):569-595
This paper explores two groups of factors, individual and institutional, that have influenced return migration since the Fukushima Daiichi nuclear accident in Japan on 11 March 2011. Based on an analysis of statistical data on evacuees, a questionnaire completed by 289 people who migrated, and 19 semi-structured interviews with disaster-affected people, the research found (apropos of institutional factors) that while the lifting of the government's evacuation order has had no immediate effect on return decisions, the termination of monetary compensation and housing subsidies has had a significant bearing on them. As for individual factors, a strong sense of attachment to home and the possession of property, job obligations, and having family members in the home location are key determinants of return decisions. Moreover, the paper suggests that there could be differing opinions among Japanese government officials and evacuees regarding radiation exposure risk and the degree to which infrastructure and social services have been rehabilitated. 相似文献
662.
D. W. Chen R. F. Carsel L. Moeti B. Vona 《Environmental monitoring and assessment》1999,57(3):291-299
An important issue in the application of mathematical models to describe or predict the fate of solutes in soil and groundwater systems is providing the necessary data to support the spatial, temporal, and hydrogeologic model parameter requirements. The larger, more complex the model and scope of application, the more likely that significant amounts of data of several types are required. A management tool is required that allows the model and the modeler to interact with various needed databases, cope with numerous database management issues, efficiently achieve model parameterization and provide visualization of model output. The three-dimensional Groundwater Modeling System (GMS) that contains a state-of-the-art flow and solute transport model and a graphical user interface for data manipulation and analysis was applied to a Superfund site in Florida to demonstrate its capabilities for predicting solute migration. 相似文献
663.
This paper tries to identify the characters that might affect interprovincial migrants'decisions and examine how and why the inftuenee of these characters changed over time individually and synthetically in China during 1985-2005.We have investigated six types of factors,namely,distance,population density,income,employment structure,house price,and migration stock.In addition,we apply the identified factors with a multiple stepwise regression model to a longitudinal dataset,which consists of interprovincial migration flows over the last two decades in China.It is found that different factors have disparate impacts on migration in China,and they can be decomposed into push force in origin area and pull force in destination area.Factors shaping China's interprovincial migration have shifted from traditional factors such as distance to economic factors such as income and employment structure.This paper suggests that more attention should be paid to obtain detailed migration data with spatial information and develop applicable models for migration processes.Our analysis provides references for development planners and policymakers to develop sound population policies to achieve regional sustainable development in China. 相似文献
664.
Renee G. Seidler Ryan A. Long Joel Berger Scott Bergen Jon P. Beckmann 《Conservation biology》2015,29(1):99-109
In much of the world, the persistence of long‐distance migrations by mammals is threatened by development. Even where human population density is relatively low, there are roads, fencing, and energy development that present barriers to animal movement. If we are to conserve species that rely on long‐distance migration, then it is critical that we identify existing migration impediments. To delineate stopover sites associated with anthropogenic development, we applied Brownian bridge movement models to high‐frequency locations of pronghorn (Antilocapra americana) in the Greater Yellowstone Ecosystem. We then used resource utilization functions to assess the threats to long‐distance migration of pronghorn that were due to fences and highways. Migrating pronghorn avoided dense developments of natural gas fields. Highways with relatively high volumes of traffic and woven‐wire sheep fence acted as complete barriers. At crossings with known migration bottlenecks, use of high?quality forage and shrub habitat by pronghorn as they approached the highway was lower than expected based on availability of those resources. In contrast, pronghorn consistently utilized high?quality forage close to the highway at crossings with no known migration bottlenecks. Our findings demonstrate the importance of minimizing development in migration corridors in the future and of mitigating existing pressure on migratory animals by removing barriers, reducing the development footprint, or installing crossing structures. Identificación de los Impedimentos para las Migraciones de Larga Distancia de Mamíferos 相似文献
665.
Abstract Migration process has become increasingly important in recent research on population and the environment. A majority of the existing migration and environment literature has focused on the environmental causes and determinants of migration. With the largest rural-to-urban migration flow in world history, and growing concerns about the environmental problems accompanying its fast economic development, China provides a particularly important case for migration and environment research. This paper reviews major migration theories and recent research on environmental effects on migration, with specific attention to the influences of environmental factors on rural-to-urban labor migration in China. A comprehensive multilevel conceptual framework is developed for studying the environmental causes of rural-to-urban migration in China. The effects of land resources on household labor migration decisions in rural China are explored to illustrate the application of this framework. 相似文献
666.
Migratory stopover habitats are often not part of planning for conservation or new development projects. We identified potential stopover habitats within an avian migratory flyway and demonstrated how this information can guide the site‐selection process for new development. We used the random forests modeling approach to map the distribution of predicted stopover habitat for the Whooping Crane (Grus americana), an endangered species whose migratory flyway overlaps with an area where wind energy development is expected to become increasingly important. We then used this information to identify areas for potential wind power development in a U.S. state within the flyway (Nebraska) that minimize conflicts between Whooping Crane stopover habitat and the development of clean, renewable energy sources. Up to 54% of our study area was predicted to be unsuitable as Whooping Crane stopover habitat and could be considered relatively low risk for conflicts between Whooping Cranes and wind energy development. We suggest that this type of analysis be incorporated into the habitat conservation planning process in areas where incidental take permits are being considered for Whooping Cranes or other species of concern. Field surveys should always be conducted prior to construction to verify model predictions and understand baseline conditions. Predicción y Mapeo del Hábitat Potencial de Descanso de la Grulla Americana para Guiar la Selección de Sitios para Proyectos de Energía Eólica. 相似文献
667.
This paper investigates the interconnections between sense-of-place dimensions across different geographical scales. While existing knowledge on sense of place has demonstrated that place meanings rest at various scales, little attention has been devoted to exploring how sense-of-place dimensions at different geographical scales can be interconnected in forming a multi-scalar construction of place meanings. In this paper, we approach this under-theorization of multi-scalarity of sense of place by looking at urban migrants’ sense of place at two geographical scales - a community culture center and the city of Guangzhou, China. In so doing, we also contribute to the scholarship on Chinese urban migrant, particularly in terms of how urban migrants reestablish their psychological connections with place of destination through specific place experiences. Our research methodology combines both quantitative (structural equation modeling analysis with 104 questionnaires) and qualitative (12 in-depth interviews) approaches. Quantitative study reaches a structural model that has not been observed by existing research, while qualitative data provide strong empirical evidence in support of the statistical relations in the structural model. Major findings in this research include: 1. at the scale of culture center, place dependence contributes strongly to both place identity and place attachment, while the latter two dimensions can be seen as parallel constructs; 2. at the scale of Guangzhou, place dependence is a dimension independent of both place identity and place attachment, and on the other hand, it is place identity that has a strong impact on place attachment; 3. migrants’ place dependence on the culture center significantly influences their place identity to Guangzhou, which further contributes to the migrants’ place attachment to the city. Although the scope of this research is limited in its sampling and research location, the empirical evidence in this paper provides a basis to argue that the construction of sense of place involves the working of sense-of-place constructs at various geographical scales. Particularly, we also argue that connecting different places across geographical scales requires a delicate network that involves various sense-of-place constructs that work both within and across scales. 相似文献
668.
669.
为揭示在溶解性有机物(DOM)作用下土壤中重金属的吸附和迁移规律并确定迁移数学模型,通过不同条件下的等温吸附实验和土柱淋滤实验,研究了溶解性有机物对重金属Cu,Cd,Pb,Zn在褐土中吸附和迁移行为的影响。结果表明DOM对Cu和Cd在土壤中的吸附促进作用较明显,对Pb有微弱的促进作用,对Zn的吸附影响不明显;随着pH的改变,25℃下Cu在土壤中的吸附高于15℃和35℃条件下。DOM质量浓度越高,Cd、Zn溶出的促进效果越明显,Cu、Pb则恰好相反。DOM对土壤中Cd、Zn的垂直迁移起着促进作用,而对Cu、Pb迁移起着一定的抑制作用;DOM对土壤重金属的平均迁移量随时间的延长而减少。此迁移模型能够定量计算并预测重金属质量浓度的时空分布。 相似文献
670.
通过分析建立闵行区环境数据中心的必要性,探讨闵行区环境数据中心的建设目标、原则和构建过程、意义、成果和不足,以期对闵行区环境数据进一步进行规范化管理。 相似文献