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41.
Increased salinity in spawning and nursery grounds in the Savannah River estuary was cited as the primary cause of a 97% decrease
in adult striped bass (Morone saxatilis) and a concomitant 96% decrease in striped bass egg production. Restoration efforts focused on environmental remediation
and stock enhancement have resulted in restored salinity patterns and increased egg and adult abundances. However, future
water needs or harbor development may preclude further recovery by reducing freshwater inflow or increasing salinity intrusion.
To assess the effect of potential changes in the salinity regime, we developed models relating discharge, tidal phase, and
salinity to striped bass egg and early larval survival and re-cast these in a quantitative Bayesian belief network. The model
indicated that a small upstream shift (≤1.67 km) in the salinity regime would have the least impact on striped bass early
life history survival, whereas shifts >1.67 km would have progressively larger impacts, with a 8.33-km shift potentially reducing
our estimated survival probability by >28%. Such an impact could have cumulative and long-term detrimental effects on the
recovery of the Savannah River striped bass population. The available salinity data were collected during average and low
flows, so our model represents some typical and some extreme conditions during a striped bass spawning season. Our model is
a relatively simplistic, “first-order” attempt at evaluating potential effects of changes in the Savannah River estuarine
salinity regime and points to areas of concern and potential future research. 相似文献
42.
Thomas M. Lewinsohn José Luiz Attayde Carlos Roberto Fonseca Gislene Ganade Leonardo Ré Jorge Johannes Kollmann Gerhard E. Overbeck Paulo Inácio Prado Valério D. Pillar Daniela Popp Pedro L. B. da Rocha Wesley Rodrigues Silva Annette Spiekermann Wolfgang W. Weisser 《Ambio》2015,44(2):154-162
Ecological science contributes to solving a broad range of environmental problems. However, lack of ecological literacy in practice often limits application of this knowledge. In this paper, we highlight a critical but often overlooked demand on ecological literacy: to enable professionals of various careers to apply scientific knowledge when faced with environmental problems. Current university courses on ecology often fail to persuade students that ecological science provides important tools for environmental problem solving. We propose problem-based learning to improve the understanding of ecological science and its usefulness for real-world environmental issues that professionals in careers as diverse as engineering, public health, architecture, social sciences, or management will address. Courses should set clear learning objectives for cognitive skills they expect students to acquire. Thus, professionals in different fields will be enabled to improve environmental decision-making processes and to participate effectively in multidisciplinary work groups charged with tackling environmental issues. 相似文献
43.
米宝昌 《中国环境管理干部学院学报》2012,(1):83-85
从明晰高校办公室工作职责、高校办公室主任应具备的能力、创新高校办公室管理模式三个方面,阐述了高校办公室工作的基本规律。通过在高校办公室多年的工作积累,总结出了高校办公室主任八方面的工作技巧。 相似文献
44.
Rachel F. Brummel Kristen C. Nelson Stephanie Grayzeck Souter Pamela J. Jakes Daniel R. Williams 《Journal of Environmental Planning and Management》2010,53(6):681-699
Policies such as the US Healthy Forests Restoration Act (HFRA) mandate collaboration in planning to create benefits such as social learning and shared understanding among partners. However, some question the ability of top-down policy to foster successful local collaboration. Through in-depth interviews and document analysis, this paper investigates social learning and transformative learning in three case studies of Community Wildfire Protection Planning (CWPP), a policy-mandated collaboration under HFRA. Not all CWPP groups engaged in social learning. Those that did learned most about organisational priorities and values through communicative learning. Few participants gained new skills or knowledge through instrumental learning. CWPP groups had to commit to learning, but the design of the collaborative-mandate influenced the type of learning that was most likely to occur. This research suggests a potential role for top-down policy in setting the structural context for learning at the local level, but also confirms the importance of collaborative context and process in fostering social learning. 相似文献
45.
Richard Bull Judith Petts James Evans 《Journal of Environmental Planning and Management》2010,53(8):991-1009
This paper takes a new look at the importance of context – institutional and political – in effective public engagement processes. It does so through a rare comparative opportunity to examine the effectiveness of processes of public engagement in two UK waste authorities, where the same waste company was involved as both the primary contractor for the delivery of the waste management service (including new energy-from-waste facilities) and, furthermore, the same staff delivered the public engagement. Interrogating these cases affords the opportunity to place flesh on the bones of the sometimes ‘abstract’ skeleton of context. While engagement processes support effective local governance in an era of partnerships and deliberative democracy, the paper identifies that the methods adopted cannot be played out devoid of detailed understanding and response to local context, including the strength of partnership working between the public and private sector, the degree of political support for engagement, and the extent to which a traditional institutional paternalism still dominates. 相似文献
46.
Trevor J. Stocki Guichong Li R. Kurt Ungar 《Journal of environmental radioactivity》2010,101(1):68-74
A method of weapon detection for the Comprehensive nuclear-Test-Ban-Treaty (CTBT) consists of monitoring the amount of radioxenon in the atmosphere by measuring and sampling the activity concentration of 131mXe, 133Xe, 133mXe, and 135Xe by radionuclide monitoring. Several explosion samples were simulated based on real data since the measured data of this type is quite rare. These data sets consisted of different circumstances of a nuclear explosion, and are used as training data sets to establish an effective classification model employing state-of-the-art technologies in machine learning. A study was conducted involving classic induction algorithms in machine learning including Naïve Bayes, Neural Networks, Decision Trees, k-Nearest Neighbors, and Support Vector Machines, that revealed that they can successfully be used in this practical application. In particular, our studies show that many induction algorithms in machine learning outperform a simple linear discriminator when a signal is found in a high radioxenon background environment. 相似文献
47.
Shigekazu Hirao Hiromi Yamazawa Jun Moriizumi 《Journal of environmental radioactivity》2010,101(11):974-984
When used with an atmospheric transport model, the 222Rn flux distribution estimated in our previous study using soil transport theory caused underestimation of atmospheric 222Rn concentrations as compared with measurements in East Asia. In this study, we applied a Bayesian synthesis inverse method to produce revised estimates of the annual 222Rn flux density in Asia by using atmospheric 222Rn concentrations measured at seven sites in East Asia. The Bayesian synthesis inverse method requires a prior estimate of the flux distribution and its uncertainties. The atmospheric transport model MM5/HIRAT and our previous estimate of the 222Rn flux distribution as the prior value were used to generate new flux estimates for the eastern half of the Eurasian continent dividing into 10 regions.The 222Rn flux densities estimated using the Bayesian inversion technique were generally higher than the prior flux densities. The area-weighted average 222Rn flux density for Asia was estimated to be 33.0 mBq m−2 s−1, which is substantially higher than the prior value (16.7 mBq m−2 s−1). The estimated 222Rn flux densities decrease with increasing latitude as follows: Southeast Asia (36.7 mBq m−2 s−1); East Asia (28.6 mBq m−2 s−1) including China, Korean Peninsula and Japan; and Siberia (14.1 mBq m−2 s−1). Increase of the newly estimated fluxes in Southeast Asia, China, Japan, and the southern part of Eastern Siberia from the prior ones contributed most significantly to improved agreement of the model-calculated concentrations with the atmospheric measurements. The sensitivity analysis of prior flux errors and effects of locally exhaled 222Rn showed that the estimated fluxes in Northern and Central China, Korea, Japan, and the southern part of Eastern Siberia were robust, but that in Central Asia had a large uncertainty. 相似文献
48.
Probability of intellectual disability is associated with soil concentrations of arsenic and lead 总被引:1,自引:0,他引:1
Background
The association between metals in water and soil and adverse child neurologic outcomes has focused on the singular effect of lead (Pb), mercury (Hg), and arsenic (As). This study describes the complex association between soil concentrations of As combined with Pb and the probability of intellectual disability (ID) in children.Methods
We used a retrospective cohort design with 3988 mother child pairs who were insured by Medicaid and lived during pregnancy and early childhood in South Carolina between 1/1/97 and 12/31/02. The children were followed until 6/1/08, using computerized service files, to identify the diagnosis of ID in medical records and verified by either school placement or disability service records. The soil was sampled using a uniform grid and analyzed for eight metals. The metal concentrations were interpolated using Bayesian Kriging to estimate concentration at individual residences.Results
The probability of ID increased for increasing concentrations of As and Pb in the soil. The Odds Ratio for ID, for one unit change in As was 1.130 (95% confidence interval 1.048-1.218) for Pb was 1.002 (95% confidence interval 1.000-1.004). We identified effect modification for the infants based on their birth weight for gestational age status and only infants who were normal size for their gestational age had increased probability of ID based on the As and Pb soil concentrations (OR for As at normal weight for gestational age = 1.151 (95% CI: 1.061-1.249) and OR for Pb at normal for gestational age = 1.002 (95% CI: 1.002-1.004)). For normal weight for gestational age children when As = 22 mg kg−1 and Pb = 200 mg kg−1 the risk for ID was 11% and when As = 22 mg kg−1and Pb = 400 mg kg−1 the probability of ID was 65%.Conclusion
The probability of ID is significantly associated with the interaction between Pb and As for normal weight for gestational age infants. 相似文献49.
为提高海洋油气管道外腐蚀速率预测的精度和效率,建立基于因子分析(FA)和天牛须搜索算法(BAS)的极限学习机(ELM)腐蚀速率预测模型。利用FA对影响因素数据集进行降维处理,确定预测模型的输入变量;建立ELM预测模型,并采用BAS对ELM模型的参数进行优化,避免参数取值随机性对模型预测性能的影响;以实海挂片试验为例,通过建模仿真评价模型的预测性能,并与其他模型进行对比分析。结果表明:FA-BAS-ELM预测模型的平均绝对误差(MAPE)仅为1.92%,决定系数R2高达0.994 9,相比于其他模型,该模型具有更优的预测性能。 相似文献
50.
In the midst of rapidly proliferating engagement efforts around climate adaptation, attention to the design and evaluation of decision support processes and products is warranted. We report on the development and evaluation of a process framework called the Vulnerability, Consequences, and Adaptation Planning Scenarios (VCAPS) process. VCAPS is a systematic approach to integrate local knowledge with scientific understanding by providing opportunities for facilitated, deliberative learning-based activities with local decision makers about climate change vulnerability and adaptation. We introduce the conceptual basis of the process in analytic-deliberation, hazard management, and vulnerability. Our evaluations from eight coastal communities where the approach was applied point to four assets of VCAPS: it promotes synthesis of local and scientific knowledge; it stimulates systems thinking and learning; it facilitates governance by producing action plans with transparent justifications; and it accommodates participant time constraints and preferences. 相似文献