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正"我们要像对贫困宣战一样,坚决向污染宣战。"这是政府工作报告中铿锵的宣言,表达了强烈的政治意愿。污染是另一种"贫困"的表现。"雾霾天气范围扩大,环境污染矛盾突出,是大自然向粗放发展方式亮起的红灯。"而"重症污染"就是一种"严重贫困",只要抬头看天、低头看水即可把症状看得一清二楚。如果镜不见花、水不见月,这样的生活有什么意思?雾霾确实已经成为很多城市的标志性难题。今年  相似文献   

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The growing interest in geologic carbon sequestration has highlighted the need for more data on how well cements react to CO2 exposure. This paper describes a series of experiments that was conducted to examine the effects of flowing carbonated brine on well cements. Class H cement pastes were exposed to the ranges of temperature (20–50 °C) and pH (2.4–5) characteristic of geosequestration conditions at a depth of about 1 km. The exposed cements and the reactor effluents were analyzed using multiple techniques including optical microscopy, X-ray diffraction, EPMA, and ICP-OES. The results showed that if the solution was pre-equilibrated with calcium carbonate, as would be expected in a limestone formation, there was no detectable attack. However, under the pH and temperature conditions to be expected in a sandstone formation, the initial rate of attack was on the order of millimeters per month. The outer layers of the cements reacted under sandstone-like conditions were fully degraded based on the results of the XRD and EPMA analyses. Inside the degraded layers there was a calcium carbonate-rich layer, a layer depleted of calcium hydroxide, and an unreacted cement core. The rate of degradation of the cement in these experiments was controlled by the rate of dissolution of the calcium carbonate-rich layer, after its formation, and diffusion through the fully degraded layers.  相似文献   

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Climate change has become a permanent feature on the global media scene and in the decision-making of policy makers. The voices of academics, scientists, politicians and commentators dominate the climate change debate, yet local knowledges and beliefs, local realities, as well as local voices and actions are essential elements of navigating the way forward. Drawing on Paton's postgraduate research, this paper broadens the current dialogue by providing a platform for grassroots Tuvaluan voices to enter the climate change debate. It explores their local realities, knowledges and beliefs, and captures what Tuvaluans hold dear – factors which must play a central role in decision-making processes. To ensure the local population is fully mobilised, it will be argued that processes for engaging local voices must build on existing forums for engagement.  相似文献   

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从家庭方面讲,关于环保知识人们又了解多少,观念上又重视多少呢?尤其是农村家庭。我采访了很多人,他们都觉得太忙,没有闲暇关心这些。谈到环保,人们表现的也很茫然,当然他们也知道沙尘暴、也知道水灾、台风和旱情,但成因就不得而知了。具体到人们的生活,什么节约水电、废物利用、垃圾的分类回收,农村人尤其是那些围着锅台转的主妇们,根本不明白为什么要这样做。因此,我认为,环保教育不在于向家庭普及些什么,如何普及才是最重要的!孩子,是纽带,是让环保走进家庭的一条有效途径。但是,让环保走进家庭,不能像布置语文作业,…  相似文献   

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We examined the connection between individuals’ relationships with the natural environment and their environmental behaviors with a focus on commitment to the environment, defined as psychological attachment and long-term orientation to the natural world. Commitment is theorized to emerge from structural interdependence with the environment and to lead to pro-environmental behaviors. Close relationships research has identified three key antecedents to commitment (satisfaction, alternatives, and investments). We developed environment-specific measures of these constructs, and factor analysis verified three distinct factors. A path analysis revealed that satisfaction with the environment and investments in the environment, but not alternatives to the environment, predicted commitment to the environment. Moreover, commitment mediated the effects of satisfaction and investments on general ecological behavior and willingness to sacrifice for the environment. In regression analyses, commitment predicted general ecological behavior and willingness to sacrifice for the environment, even when controlling for ecological worldview, inclusion of nature in the self, connectedness to nature, and environmental identity. Individuals who are satisfied with and invested in the natural world are likely to be committed to the environment and act with the well-being of the environment in mind.  相似文献   

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Oil to 2000     
Current surplus oil production capacity had its origins in the price increases of the 1970s. Those increases encouraged both energy conservation and the entry of new producers. Recent increases in oil demand reflect the belief among energy users that in real terms in the long term, prices will be stable. There is good reason to believe that this will be so, even at the current rate of increase it will be 15 years before demand matches current capacity. Given that situation it is difficult to see OPEC following any other pricing policy than the one currently in place. In the meantime market prices will further encourage vertical integration.  相似文献   

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In the Discussion, Nash et al. (2019) estimate the seasonal change in groundwater volume for a portion of the restored Sierra Nevada Meadow that we evaluated (Hunt et al. 2018) and use this estimate as an upper bound on the possible contribution to flow that is attributable to restoration. The authors conclude that raising the channel bed elevation and reconnecting the meadow floodplain most likely reduced summer streamflow. In contrast, we report at least a fivefold increase in baseflow from the meadow in the years following restoration. In addition, we observed that, after restoration, the previously intermittent stream below the meadow flowed continuously throughout the summer months, despite record drought conditions, and in 2015, the lowest snowpack on record. We suggest that the groundwater budget presented in the Discussion may not adequately represent conditions within the meadow because the authors extrapolate from 5 near‐channel groundwater wells across 62 ha of meadow and assume an area of influence that is approximately one‐sixth of the meadow area. We conclude that the conversion of an intermittent stream to perennial flow during drought conditions is a stronger check on our gauge data than the groundwater budget presented in the Discussion.  相似文献   

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Our massive tampering with the world's interdependent web of life-coupled with the environmental damage inflicted by deforestation, species loss, and climate change-could trigger widespread adverse effects, including unpredictable collapses of critical biological systems whose interactions and dynamics we only imperfectly understand. Uncertainty over the extent of these effects cannot excuse complacency or delay in facing the threats ... We the undersigned, senior members of the world's scientific community, hereby warn all humanity of what lies ahead. A great change in our stewardship of the earth and the life on it is required, if vast human misery is to be avoided and our global home on this planet is not to be irretrievably mutilated. (Union of Concerned Scientists, 1992)  相似文献   

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