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921.
以碳捕集与封存为典型的新兴技术在应对气候变化上的降碳功能显著,但该技术颇具不确定性。“决策于未知”成为政府规制技术风险的真实写照,如何在鼓励碳捕集与封存技术发展,助力“双碳”目标实现的同时,应对随之而来的风险挑战与安全诉求,既是国家必须肩负的义务,也是回应公众期待的内在要求。应运而生的风险预防原则作为应对气候变化的重要举措,为技术风险规制提供了合法性与正当性基础,对于碳捕获、封存技术发展与碳中和目标实现具有重要现实意义。为此,风险预防原则在技术规制中,应当整体遵循弱风险预防理念,彰显秩序、正义和效率的多元价值诉求,实现科学理性与社会理性的平衡。在此基础上,通过多手段的综合应用,开放的风险决策结构,强化风险管理的动态调试,以预防性环境行政公益诉讼为保障,将风险预防原则融汇于碳捕集与封存技术风险规制中。  相似文献   
922.
Although satellite radar altimetry was developed and optimized for open oceans, it has been used to monitor variations in the level of inland water-bodies such as lakes and rivers. Here, for the first time, we have further used the altimetry-derived variation of water level for estimating the fluctuation of water storage as an addition to the present in situ water storage estimation systems to be used in remote areas and in emergency situation such as in the events flooding monitoring and for studying the effect of climate change. Lake Dongting, the second largest lake in China, influenced frequently by flooding, was, therefore, chosen to demonstrate the potential of the technique. By using the concept of an “assumed reference point”, we converted Topex/Poseidon satellite altimetry data on water level variations in Lake Dongting to “water level” data. The “water level” time-series data and in situ water storage were used to establish a rating curve. From the rating curve, we converted data on “water level” derived from seven years (1993–1999) of Topex/Poseidon data to actual water storage in Lake Dongting. The result reveals that the seasonal and annual fluctuations of water storage occurred during the 1990s with a more frequent flooding at the late 1990s' especially the flooding in whole catchment level in 1998 and 1999. The study supports the usefulness of satellite altimetry for dense and continuous monitoring of the temporal variations in water dynamic in moderate to large lakes.  相似文献   
923.
对比了用流式细胞术现场测定及用多聚甲醛、戊二醛及两者的混合物这三种常用固定剂进行固定保存对微微型浮游生物样品的影响。结果表明,在1个月内,细胞数量变化并不显著,但随着保存时间的增加,细胞数量明显减少,且散射光信号明显增大。除原绿球藻的藻红素荧光基本不变、微微型真核浮游植物的藻红素荧光大幅增加外,其余荧光信号均发生不同程度的减少。同时,戊二醛所引起的微微型真核浮游植物荧光信号的极大改变会影响类群的界定。如有可能,应该尽量现场测定微微型浮游生物样品,否则建议采用多聚甲醛或其与戊二醛的混合物作为固定剂,将样品保存于液氮中,待返回实验室后尽快进行测定。  相似文献   
924.
为探究高温作用对泥岩盖层密封性的影响,从理论上剖析储气库盖层产生热应力的3种形式,在室内试验的基础上,分析泥岩在高温环境下力学损伤程度和盖层物性封闭评价指标随温度变化特征.结果表明:高温环境下泥岩整体结构性能降低,400℃左右是泥岩在周期热应力作用下损伤的阈值温度;高温作用会显著改变泥岩盖层物性封闭特征,400℃左右是...  相似文献   
925.
岩浆侵蚀区煤层孔隙结构特征及其对瓦斯赋存之影响分析   总被引:12,自引:1,他引:11  
在煤样煤层瓦斯含量、瓦斯组分和煤的孔容特征的实验测定基础上 ,分析了岩浆岩侵蚀区煤层瓦斯组分特征 ;研讨了孔隙结构特征 ,岩浆岩侵蚀对煤层孔隙瓦斯赋存及涌出的影响规律。这些结果为煤矿井田不同区域开采时 ,选用安全技术措施提供了科学依据  相似文献   
926.
本文就污水海洋处置中等截面扩散器的水力分配问题,结合上海市污水排海工程实际进行了模型试验,并在建立的水力特性模式基础上对排放口局部阻力系数进行了分析率定,经检验与试验其他结果相吻合,说明采用的模式是可行的,对同类研究具有一定的参考价值。  相似文献   
927.
土地利用变化对碳排放的影响   总被引:4,自引:0,他引:4  
大气中温室气体浓度增加是人类面临的严峻挑战.土地利用变化已成为仅次于化石能源燃烧的第二大温室气体排放源.本文在界定土地利用变化碳排放作用机制及内涵的基础上,从农用地向非农用地转换、农用地内部土地利用以及非农用地内部土地利用三个方面综述了土地利用变化对碳排放的影响.农用地向非农用地的转换会增加碳排放量.农用地内部土地利用变化方面,农田转换为森林或草地能够使土壤和植被碳储量增加,但是土壤碳汇集速率存在一定的差异;农田、森林和草地管理措施对生态系统碳循环的影响目前还存在争议,但基本观点是合理的管理措施能够减少碳排放置.非农用地内部土地利用变化方面,从能源消耗角度考虑,二产用地向三产用地转换会减少碳排放量.因此合理组织土地利用对帮助我国实现碳减排承诺,发展低碳经济有重要意义.  相似文献   
928.
A study designed to analyze two types of information services provided by the Water Resources Scientific Information Center (WRSIC) is described. This study was conducted to assess the monetary value and acceptability to users of the Selected Water Resources Abstracts (SWRA) Journal and the Selective Dissemination of Information (SDI) System. Results indicate that both services were well received and provide a useful and valuable service to a variety of users active in the area of water resources.  相似文献   
929.
ABSTRACT: Zooplankton colonization was followed for 16 months in Lake Oconee, Georgia, a new pumped storage reservoir. Data were interpreted to identify differences among stations and seasons, as a function of the reservoir's early stage of development and of pumped storage operations. Colonization was rapid, and the zooplankton community was characterized by a high species diversity; approximately 40 rotifer species and 14 cladoceran genera were recorded. Zooplankton density varied along an environmental gradient from riverine to lentic conditions. Rotifer abundance varied from 104-106 individuals/m3, with maxima in the summers Copepod and cladoceran densities ranged from 103 to nearly 105 individuals/m3; maxima for stations other than the dam were observed in the summer and early fall, but high values at the dam station occurred throughout winter 1980. When pumped storage operations began in December 1979, zooplankton densities increased at the dam station. Pumpback decreased the intensity of the environmental gradient from riverine to lentic conditions, and led to a more similar zooplankton community structure throughout the reservoir.  相似文献   
930.
Several large agricultural pumps, located in the upper St. Johns River Basin, Florida, and representative of the numerous pumps operating in the basin, were monitored during the spring and summer of 1982. These pumps have rated capacities ranging from 36 to 334 ft3/s and drain various quantities of improved pasture, row crop, and citrus land uses. The combined total pumping capacity of the pumps in this study is approximately equal to the average flow at US 192, near Melbourne (691 cfs). Results indicate high nutrient and suspended solids loading to the river, but the relative magnitude of each parameter varies with pump site and date. The row crop/Mary A pump (267 ft3/s capacity) exhibited the poorest water quality of the sampled pumps and appeared to have the greatest pollutional potential. The average suspended solids loading rate from the Mary A pump was high (37,900 Kg/day). The average total nitrogen (TN) and total phosphorus (TP) discharge concentrations at this pump were also high, with values of 3.96 mg/L and 0.79 mg/L, respectively. As expected, nutrient loading rates reflected discharge rates, to a large degree. Average TN loading rates for the pumping stations varied from 86 to 1935 Kg/day while TP loading ranged from 7 to 390 Kg/day. Nutrients from pumping are contributing factors to the increasing aquatic plant growth and algal blooms in the area. Poor quality discharge water, as well as rapid rises in water level from the cumulative discharges resulting in dead marsh vegetation and accompanying oxygen sags, have been suggested as causative factors for fish kills in the area.  相似文献   
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