流-固耦合作用下某尾矿库稳定性数值模拟研究

以南方某铀尾矿库为对象,利用COMSOL有限元软件开展某尾矿库在不同降雨强度下的稳定性分析。结果表明:在不同的降雨条件下,尾矿坝最先可能发生溃坝的是基岩与尾矿坝接触的尾端,其次是尾矿坝与基岩接触的地方。同时,随着降雨强度的增大,尾矿坝的稳定性也会随之下降,位移量会增大,溃坝的可能性也会变大。     

场地参数对地下水污染物健康风险评价影响的初步研究

通过单变量分析,考察含水率、容重和地下水埋深对挥发性有机污染物风险控制值的影响,结果表明土壤含水率、土壤容重和地下水埋深与风险控制值为正相关关系,土壤含水率和容重在超过某一阈值后,微小变化会使风险控制值产生较大的波动,因此建议在实际调查过程中提高水文地质勘察取样和测试质量,获得高代表性的数据,减少风险控制值的不确定性。     

矿区河流中氟化物的多源贡献量计算及环境背景值确定

环境背景值反映了环境质量的原始状态,是确定区域环境污染程度的基础,在环境质量评价、政府决策中起着十分重要的作用。对于具有矿产背景的区域,由于其水文地质环境复杂,传统背景值的计算方法存在局限性。笔者以明白河流域为研究对象,利用水文分析工具,结合实际采样检测,将流域内氟化物的来源分为4类,单独进行估算,并利用研究区出境断面处的多年历史数据对估算结果进行验证,预测精度达到89.4%;最后只考虑自然因素对总量的贡献,计算出河流中氟化物的背景值为1.72 mg/L。     

Potential for cascading impacts of environmental change and policy on indigenous culture

Global environmental and societal changes threaten the cultures of indigenous peoples and local communities (IPLC). Despite the importance of IPLC worldviews and knowledge to sustaining human well-being and biodiversity, risks to these cultural resources are commonly neglected in environmental governance, in part because impacts can be indirect and therefore difficult to evaluate. Here, we investigate the connectivity of values associated with the relationship Ngātiwai (a New Zealand Māori tribe) have with their environment. We show that mapping the architecture of values-environment relationships enables assessment of how deep into culture the impacts of environmental change or policy can cascade. Our results detail how loss of access to key environmental elements could potentially have extensive direct and cascading impacts on the cultural values of Ngātiwai, including environmental responsibilities. Thus, considering only direct effects of environmental change or policy on cultural resources, or treating IPLC social-ecological relations simplistically, can severely underestimate threats to cultures.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01670-3.     

Attitudes of Private- and Public-Land Managers in Wyoming, USA, Toward Beaver

Castor canadensis ) management in Wyoming, USA, was sent to 5265 private-land managers and 124 public-land managers during 1993. The survey was developed in response to increasing interest in beaver management and beaver reintroduction possibilities. Private-land managers responding to the survey supplied information on 62,859 km² of land area and 20,037 km of streams. Primary concerns about beaver damage centered on (in decreasing order of importance) blocked irrigation ditches, girdled timber, blocked culverts, and flooded pastures, roads, crops, and timber. Primary benefits that landowners perceive that beaver give them were, in order of importance, elevated water tables, increased riparian vegetation, and increased stock-watering opportunities. Public-land managers also listed these benefits and detriments among their top concerns for beaver. Over 45% of landowners with beaver on their property and all of the public-land managers displayed an interest in a beaver reintroduction program and in more proactive beaver management.     

Valuation of Spatial Configurations and Forest Types in the Southern Appalachian Highlands

Site-specific estimates of the values of spatial configuration and forest composition are presented. Amenity values of forest patches are found to vary the most by urban and sprawling development patterns of specific areas and forest types. For example, smaller patches of deciduous forest are more highly valued in the urban and sprawling areas of Greensboro, North Carolina, whereas larger patches of deciduous forest are more highly valued in the urban and sprawling areas of Greenville, South Carolina. Within the Greenville and Greensboro areas, visible landscape complexity is highly valued for deciduous and evergreen forest patches, whereas lower visible landscape complexity, i.e., smoothly trimmed forest patch boundaries, is highly valued for mixed forest patches.     

湖北省2008年初低温雨雪冰冻过程气候特征分析

2008年初,湖北省出现了严重的低温雨雪冰冻灾害,直接经济损失高达110亿元以上,有必要对灾害期间的气候特征进行系统、科学的分析和总结。对湖北省76个气象站2008年1月12日～2月3日气温、降水（雪）、日照以及低温持续日数等要素进行时空间差异分析及历史与同期比较,并选取10个代表站历史上所有低温雨雪天气过程,对其过程持续低温日数、最长连续雨雪日数、过程极端低温进行比较分析。结果表明：（1）此次过程的平均气温异常偏低,该省大部为-1～-2℃,比常年同期偏低4～6℃,为各站历史同期最低,其中主要是最高气温异常偏低所致,但极端低温并不低;（2）降雪过程频繁,雨雪量异常偏多;（3）低温冰冻持续时间长,该省大部在16～22 d,位于历史第一;（4）日照异常偏少。持续而稳定的大气环流异常形势是湖北省大范围低温雨雪天气的直接原因。     

Daily Precipitation Extremes in Iran: Decadal Anomalies and Possible Drivers

This study focuses on the empirical statistical analysis of the anomalies in daily precipitation extremes by applying the quantile perturbation method (QPM) to data from 31 Iranian weather stations during the period between 1961 and 2005. The possible causes behind the anomalies in precipitation extremes are identified by analyzing their relationship with the anomalies in eight atmospheric indices (i.e., NAO, SOI, PDO, AMO, NCP, DMI, WeMO, SSN). In terms of decadal oscillations, the country was generally wet in the 1960s and 1970s with most stations exhibiting periods of higher quantile perturbations, whereas lower quantile perturbations were dominant in the 1980s and 1990s. The highest perturbation in extreme precipitation quantiles prevails in Central Iran during the early 1980s, in which the quantiles are about 50% higher than the ones based on the full time series. The frequency of significant precipitation anomalies for winter season was greater than that for spring and autumn seasons. For the summer season, the humid region in North Iran demonstrates strong positive anomalies. The results highlight the noticeable role of large‐scale climatic factors in the anomalous behavior of precipitation extremes in Iran. The atmospheric drivers of the quantile anomalies in extreme precipitation were found to differ from one season to another.     

近50年湖北省降水变化特征分析

在气候变化背景下,区域降水变化波动较大。湖北地处亚热带,位于典型的季风区内,旱涝灾害比较突出,特别是水患,历来是威胁湖北的一大灾害,因此对降水时空变化进行分析研究,有很现实的意义。利用1961年以来全省65站逐日降水观测资料为基础,根据气候特征和行政区划将湖北省进行区域划分,利用多种统计分析方法,以揭示在全球气候变暖背景下湖北省各区域的降水变化事实。结果表明：湖北省平均年降水量鄂西北最少,鄂东南最多,秋季降水量的减少和冬季降水量的增加最为显著;极端降水事件的变化中,鄂西北发生站次最多,江汉平原其次,鄂西南和鄂东南最少。该结论为湖北各区域的旱涝变化趋势预估、为水资源管理和防汛抗旱工作提供科学的参考     

In vivo and in vitro metabolism of tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), by the freshwater planarian, Dugesia japonica

Cigarette smoke is a risk factor for human health, and many studies were conducted to investigate its adverse effects on humans and other mammals. However, since large amounts of cigarette products are produced and consumed, it is possible that tobacco chemicals can end up in aquatic environments through several routes, thus influencing aquatic organisms. In this study, the presence of tobacco-specific nitrosamine (TSNA), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), in aquatic environment was demonstrated. Since toxic effects on and distribution patterns of tobacco chemicals in aquatic organisms were rarely studied, after results of an acute toxicity pretest were obtained, experiment was conducted to investigate the bioaccumulation pattern of NNK and distribution patterns of its metabolites, mainly 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), in NNK-treated freshwater planarians, Dugesia japonica. Results from in vivo and in vitro studies showed that NNK was readily converted to NNAL through the carbonyl reduction in bodies of NNK-treated planarians. Tissue concentrations of both chemicals increased in time- and dose-dependent manners. Furthermore, we examined the end products of NNK/NNAL α-hydroxylation in NNK-treated planarians, but only 1-(3-pyridyl)-1,4-butanediol was detected, suggesting that NNK metabolism in planarians partially differs from that in mammalian systems. This is the first report on NNK metabolism in an aquatic organism and can be used as a foundation for developing freshwater planarians as a new in vivo model for the study of NNK toxicology in the future.