达里诺尔湖近2400年以来Hg元素含量变化及环境意义

汞（Hg）元素作为一种全球性循环元素,对环境的影响正逐渐成为人们关注的焦点之一.为揭示寒旱区达里诺尔湖沉积物的Hg污染历史及人类活动对湖泊沉积物中Hg污染的影响,通过采集湖泊沉积物岩芯（编号DL1）,在建立DL1岩芯沉积地层年代框架的基础上,结合沉积物粒度特征、总有机质（TOC）含量等指标参数的变化,对DL1岩芯记录的地质历史上的Hg含量变化特征及环境意义进行了综合分析.结果显示,沉积物记录的Hg元素污染具有明显的阶段性变化特征：2400~1400 cal.a BP,Hg含量呈逐渐降低趋势,期间降水量呈逐步减少趋势,区域气候显著干旱;1400~200 cal.a BP,Hg含量相对稳定,呈小幅度波动变化,对应了区域气候的干-湿交替;近200 cal.a BP以来,Hg含量明显增加,这可能是受人类活动影响的结果.整体上,地质历史上DL1沉积物中Hg含量变化受气候干冷-暖湿交替周期性变化影响较大.而近200 cal.a BP来Hg与TOC等指标间显著正相关,则显示了沉积物中有机质可能吸附了大量的Hg元素,使其呈顶端富集趋势,进而对湖泊水生态环境造成影响.     

事故车辆影响下的城市三车道道路交通流仿真

为探究事故车辆对城市三车道道路交通影响机制,首先,分析考虑事故车辆的城市三车道道路交通流特征;然后,构建左车道优先且考虑主动抢道和被动抢道行为的元胞自动机交通流模型;最后;研究事故持续时间td变化时事故车辆分别位于M道和R道的城市道路交通流演化.结果 表明:事故车辆会形成交通瓶颈,呈现上游车辆聚集下游车辆稀疏的时空特征...     

Urbanisation and flood vulnerability in the peri-urban interface of Mexico City

Chronic flooding in the Chalco valley, state of Mexico, Mexico, is the outcome of past and present socio‐environmental changes which have taken place in Mexico City's south‐eastern peri‐urban interface. This flooding is the result of a complex interaction between urbanisation in an ex‐lacustrine area, permanent ecological deterioration and ground subsidence, poor sanitation and inadequate policy responses. Far from solving the flooding problem, short‐term policy responses have created increasingly unsafe conditions for current residents. A socio‐historical analysis of disasters reveals the importance of taking into consideration particular social actors and institutions in hazard generation and flood vulnerability over time. This paper analyses three aspects of this flooding: first, the importance of approaching floods from a socio‐historical perspective; second, the relation between urbanisation, former policies and flood risk generation; and third, current policy responses to and the failure in the risk management of La Compañía Canal.     

Framing of Geoengineering Affects Support for Climate Change Mitigation

The growing recognition that climate change mitigation alone will be inadequate has led scientists and policymakers to discuss climate geoengineering. An experiment with a US sample found, contrary to previous research, that reading about geoengineering did not reduce conservatives’ skepticism about the existence of anthropogenic climate change. Moreover, depending on how it is framed, geoengineering can reduce support for mitigation among both conservatives and non-conservatives. When geoengineering is framed as a major solution, people worry less about climate change, leading to reduced mitigation support. When framed as disastrous, people perceived geoengineering as riskier, also leading to a decrease in mitigation support. A more moderate framing of geoengineering as a partial solution is less susceptible to moral hazard effects. Overall, results suggest that geoengineering will not lessen political polarization over anthropogenic climate change, and could undercut support for mitigation efforts. Instead, framing geoengineering as a small piece to solving a big puzzle seems to be the best strategy to weaken this potential moral hazard.     

Psychological Reactance From Reading Basic Facts on Climate Change: The Role of Prior Views and Political Identification

Scholars continue to search for solutions to shift climate change skeptics’ views on climate science and policy. However, research has shown that certain audiences are resistant to change regarding environmental issues. To explore this issue further, we examine the presence of reactance among different audiences in response to simple, yet prominently used, climate change messages. Our results show that emphasizing the scientific consensus of climate change produces reactance, but only among people who question the existence of climate change. Moreover, adding political identification to the model as an additional moderating variable shows the increases in reactance occur among Republicans who question the existence of climate change. Finally, our results show that reactance to climate change messaging may lead to backfiring effects on important outcomes tied to climate change such as risk perceptions, climate change beliefs, and support for mitigation policies.     

Unintended Effects of Emphasizing the Role of Climate Change in Recent Natural Disasters

In 2017, the United States experienced a series of natural hazards (hurricanes, wildfires, and blizzards) that resulted in significant loss of life and property. Emphasizing the role of climate change in these events might offer an important tool for engagement, particularly with skeptical audiences. However, in a survey experiment (N?=?1504) involving three different natural hazards – hurricanes, wildfires, and blizzards – we find that emphasizing the role of climate change in these hazards produced unintended effects for climate change skeptics. In particular, skeptics experienced resistance to the news article, which associated with reduced perceived hazard severity. These backfiring effects likely serve as a defensive mechanism used by skeptics to maintain their prior views of climate change, illustrating the challenges faced in communicating climate change to skeptical audiences. These findings offer additional insight for those attempting to communicate climate-related risk information to skeptical audiences.     

Optimizing Messaging to Reduce Red Meat Consumption

Red meat production has a range of negative environmental impacts. We sought to characterize the motivations, environmental attitudes and demographics of red meat-eaters, and examine the effect of message framing in reducing future meat consumption. Canadian adult meat-eaters (593) completed a survey and were randomly assigned to one of six message treatments that presented information on the environmental impacts of meat production using frames representing social norms and/or place identity constructs. Taste and quality were the most important motivators for eating meat, while moral/ethical factors were the least. Forty-nine percent of respondents indicated they would reduce red meat intake after exposure to an information only message, while the social norms frame was more effective than others (χ2). Awareness of the environmental effects increased significantly after messaging for all 13 impacts. These findings should assist communicators with designing more effective messaging aimed at encouraging pro-environmental behaviours associated with meat consumption.     

Soil erosion vulnerability under scenarios of climate land-use changes after the development of a large reservoir in a semi-arid area

Climate and land-use/cover changes (LUCC) influence soil erosion vulnerability in the semi-arid region of Alqueva, threatening the reservoir storage capacity and sustainability of the landscape. Considering the effect of these changes in the future, the purpose of this study was to investigate soil erosion scenarios using the Revised Universal Soil Loss Equation (RUSLE) model. A multi-agent system combining Markov cellular automata with multi-criteria evaluation was used to investigate LUCC scenarios according to delineated regional strategies. Forecasting scenarios indicated that the intensive agricultural area as well as the sparse and xerophytic vegetation and rainfall-runoff erosivity would increase, consequently causing the soil erosion to rise from 1.78 Mg ha^?1 to 3.65 Mg ha^?1 by 2100. A backcasting scenario was investigated by considering the application of soil conservation practices that would decrease the soil erosion considerably to an average of 2.27 Mg ha^?1. A decision support system can assist stakeholders in defining restrictive practices and developing conservation plans, contributing to control the reservoir's siltation.     

Influencing climate change regulations: examining responses from large-scale firms

Recent climate change projections and a push towards a universal agreement on carbon emission reductions suggest that firms will need to respond to future regulatory changes. This paper employs an influencing strategies lens to examine how large-scale firms might respond to future climate change regulations. The study uses a structured qualitative methodology to explore and explicate the strategic responses from 21 international firms to the proposed emissions trading scheme outlined in Australia's Garnaut Climate Change Review. The results of the analysis show that firms can use pre-emptive influencing strategies in attempts to shape and mould regulatory design parameters, secure high levels of transitional economic support, and shift the balance of public policies and expenditure. Complementary defensive strategies may also target policy makers and regulators with some of the potential negative consequences of the new regulations.     

The News You Choose: news media preferences amplify views on climate change

How do choices among information sources reinforce political differences on topics such as climate change? Environmental sociologists have observed large-scale and long-term impacts from news media and think-tank reports, while experimental science-communication studies detect more immediate effects from variations in supplied information. Applying generalized structural equation modeling to recent survey data, previous work is extended to show that political ideology, education and their interaction predict news media information choices in much the same way they predict opinions about climate change itself. Consequently, media information sources serve as intervening variables that can reinforce and, through their own independent effects, amplify existing beliefs about climate change. Results provide empirical support for selective exposure and biased assimilation as mechanisms widening political divisions on climate change in the United States. The findings fit with the reinforcing spirals framework suggesting partisan media strengthens climate change beliefs which then influences subsequent use of media.