生物乙醇生产及纤维素酶的开发进展

随着石化燃料由短缺变成枯竭,能源危机是人类面临的共同问题。寻找新的能量来源关系到经济的可持续发展乃至人类的生存问题,生物乙醇作为一种可再生的、经济上可承受的,并且对环境安全的能源物质将逐渐成为石油的替代品。提高纤维素酶的产量,降低纤维素酶的成本成为提高纤维素生产生物乙醇的市场的竞争力的关键因素。该文从生物乙醇的产业发展和纤维素酶的开发进展进行综述,为今后生物乙醇生产产业的提升、纤维素酶工程菌的开发提供基础。     

巴西三位一体的生物柴油战略

有害气体排放超标、全球气候变暖、石油价格居高不下、可再生资源日渐匮乏……面对一系列生态难题,人类该如何应付？生物柴油正日益成为能源发展的新选择。然而,对于大规模采用生物柴油这一战略选择,究竟利大于弊,还是弊大于利,众说纷纭。权衡标准也呈现多样性：一是商业标准,发展生物柴油是否经济;二是生态标准,生物柴油是否是对环境健康的能源;三是社会标准,即发展生物柴油是否有利于社会问题的缓解。巴西是世界大规模开发生物柴油最早的国家,巴西发展生物柴油,实现“能源-环境-社会”三位一体的发展生物柴油战略值得关注。     

试论美国的中亚能源战略

由于中亚优越的地理位置、丰富的能源战略资源，使其成为大国争夺的目标。本文通过阐述中亚能源状况及潜在经济利益，分析美国对中亚能源战略实施的各种手段，预测其发展及影响。     

极地环境污染物的微生物降解及其生物修复研究进展

随着人类社会的发展及其对未知世界探索能力的提高,环境污染目前已演变成为全球性问题,即使是远离人类居住地的南北极地区也不能幸免。任何污染在极地这样一个生态系统组成单调、环境承载能力脆弱的地方都可能带来严重后果,因此极地环境的污染治理尤为迫切。生物修复技术作为环境治理的重要方法与手段,受到了普遍关注。本文简要介绍了极地环境的污染现状以及近年来应用微生物开展极地环境污染物降解与生物修复的主要进展,并就研究中的一些潜在问题展开讨论。极地环境的污染治理与生物修复,将是21世纪环境微生物学研究人员的一项重要使命。     

大国因素对当今中国-伊朗关系的影响

中国与伊朗都是世界上文明的古国.两国交往的历史源远流长.目前中国是世界上第二大能源进口国,伊朗则是世界上石油储量占第三位、天然气储量占第二位、欧佩克内部能源出口量占第二位的能源生产和输出大国,两国间经贸发展的前景广阔.但是,美国等西方大国却会对中国-伊朗之间关系的发展设置障碍,带来正面或负面、现实或潜在的影响.     

前景广阔的生物能源

生物能源（又称绿色能源）是指从生物质取得的能源，它是人类最早利用的能源。古人钻木取火、伐薪烧炭，实际上就是在使用生物能源。但是通过生物质直接燃烧获得能量是低效的。随着工业革命的进程，化石能源大规模使用，生物能源逐步被以煤炭和石油天然气为代表的化石能源所替代。     

能源地理研究的发展与展望

能源系统与人类社会的相互作用关系是能源地理研究的主要内容,涉及经济、政治、环境和文化等多个维度。能源的不均衡分布与空间流动及其环境效应吸引了地理学者的关注,同时地理学者又可以通过独特的视角与研究方法分析能源问题。能源地理研究因人类在地球表层能源系统中的经济活动和地缘政治而兴起,又因全球气候变化的挑战和社会公平的讨论而进入新的繁荣阶段。由于中外所处的发展阶段不同,能源环境问题存在差异,又因学术氛围不同,所以学者们在关注视角和研究特色等方面存在不同侧重。国际能源地理研究以资源分布及经济地理研究为起点,在能源环境问题的牵引下逐渐形成了学术共同体,并在长期发展历程中出现了能源生产网络与能源流动、能源地缘政治与能源安全、能源转型与气候治理、能源正义与能源贫困等多元研究议题,可为中国学者提供诸多有益借鉴。中国能源地理研究从20世纪中叶起大致形成了“世界资源地理”和“部门经济地理”两个脉络的传统,并持续面向国家战略需求开展经世致用的应用研究,21世纪以来在碳排放与居民能源消费等方面的研究逐步与国际接轨。近年来,在强调“双碳”目标、能源转型和能源安全的背景下,能源地理研究迎来了新的发展机遇,但也存在学...     

作物—牲畜—生物能源综合系统对中国农业源温室气体的影响评估

对农作物和畜牧业生产系统中的剩余秸秆和粪便进行生物能源化利用,不仅有利于缓解作物—牲畜系统农业剩余物排放对环境造成的压力,还能通过最终产品的使用来抵消相关的温室气体排放。本文构建了一个作物—牲畜—生物能源一体化的综合系统框架,基于生命周期评价法估算了2010—2019年中国及各省份作物和畜牧生产系统中各过程的温室气体排放清单;对比了作物—牲畜—生物能源综合系统和传统系统在不同生产环节的排放差异,评估了综合系统对农业源温室气体排放的环境影响。研究结果显示：(1)作物秸秆管理、牲畜肠道发酵和作物生产能源消耗贡献了基准情景下中国主要的农业源温室气体排放,作物和牲畜系统中温室气体来源呈现出显著的地区差异。(2)环境影响强度在部分地区或省份呈现波动变化趋势,其中,华东地区的排放强度下降幅度较大(-0.73×10^-2),新疆的增幅最大(0.63×10^-2)。(3)作物和畜牧生产系统中可利用的剩余秸秆和粪便数量可观,综合系统对农业源温室气体排放起到缓解作用,全国范围内缓解程度不同,最大时可减缓约67%的环境影响。     

水资源在粮食和能源生产中的应用

人类生存每天必须消费2—3升水。而美国为维持高标准生活水平,每人大约要消耗7200升/天,其中部分直接用于个人生活和工业需要,72％的水用于粮食和能源生产。美国的西部地区水资源贫乏,奥加尔水库水位下降,柯洛莱达河流域水分亏缺,以及圣·约翰谷地水资源不足是这一威胁的征兆。水源不足还在美国东部少数地区出现。由于农业和能源生产过程需要消耗大量的水,特别是到2000年,美国计划粮食生产增加约30％,生物能源生产系统增加5—20倍,从煤和油岩中提炼混合燃料量增加2—5倍。水将成为未来能源生产的限制因素之一。本文拟将水资源短缺对未来粮食和能源生产的影响因素作一分析。     

中国能源保障基本形势分析

国家能源保障目标由两部分组成： 第一,能源供应的稳定性,指满足国家人口发展正常需 求的能源供应保障的稳定程度;第二,能源使用的安全性,指能源消费及使用不应对人类自身的 生存与发展环境构成任何威胁。本文从影响能源保障的能源资源基础、生产与消费、运输、生产与 消费对环境影响等方面分析了中国能源保障的基本形势, 总体来说中国目前能源保障重点集中 在能源供应保障层面上, 立足于自身的资源基础及生产与消费空间高度分离的特点建立起了庞 大的能源保障体系, 对能源使用安全尽管已经引起了高度的重视, 但是由于现实经济的压力和认 识上的不足实质性的措施还很少。未来我国应该立足能源保障基本形势, 从供应稳定性和使用安 全性出发构筑稳定、经济、清洁、安全的能源保障体系。     

Ethanol Production: Energy and Economic Issues Related to U.S. and Brazilian Sugarcane

For a thorough and up-to-date evaluation of all the fossil energy costs of ethanol production from sugarcane in both the U.S. and Brazil, every energy input in the biomass production and ultimate conversion process must be included. In this study, more than 12 energy inputs in average U.S. and Brazilian sugarcane production are evaluated. Then in the fermentation/distillation operation, nine more fossil fuel inputs are identified and included. Some energy and economic credits are given for the bagasse to reduce the energy inputs required for steam and electricity. Based on all the fossil energy inputs in U.S. sugarcane conversion process, a total of 1.12 kcal of ethanol is produced per 1 kcal of fossil energy expended. In Brazil a total of 1.38 kcal of ethanol is produced per 1 kcal of fossil energy expended. Some pro-ethanol investigators have overlooked various energy inputs in U.S. and Brazilian sugarcane production, including farm labor, farm machinery, processing machinery, and others. In other studies, unrealistic low energy costs were attributed to such energy inputs, as nitrogen fertilizer, insecticides, and herbicides. Both the U.S. and Brazil heavily subsidize ethanol production. Thus billions of dollars are invested in subsidies and this significantly increases the costs to the consumers. The environmental costs associated with producing ethanol in the U.S. and Brazil are significant but have been generally overlooked. The negative environmental impacts on the availability of cropland and freshwater, as well as on air pollution and public health, have yet to be carefully assessed. These environmental costs in terms of energy and economics should be calculated and included in future ethanol analyses so that sound assessments can be made. In addition, the production of ethanol in the U.S. and Brazil further confirms that the mission of converting biomass into ethanol will not replace oil. This mission is impossible. General concern has been expressed about taking food crops to produce ethanol for burning in automobiles instead of using these crops as food for the many malnourished people in the world. The World Health Organization reports that more than 3.7 billion humans are currently malnourished in the world—the largest number of malnourished ever in history.     

实现纤维素生物质能源的可持续发展(英文)

生物质是一种丰富易得的清洁能源,具有大幅减少温室气体排放的潜力。与以玉米及其他谷物为原料的生物质能源生产技术相比,由于纤维生物能源生产消耗的化石能源较少(化石能源与碳的比值低)而备受关注。然而,生物燃料生产系统并非简单,受到多种因素的影响,如能量供应、农村的经济发展水平、土地和生态系统的保护、温室气体减排的可能性以及社会培训等。本文简要综述生物质能源开发的经济与环境影响。根据区域气候和生态条件,不同地区具有各自的生物质种类或能源作物的优化组合。在不久的将来,生物质能源开发的生物技术所面临的挑战包括:生物质形成与细胞壁分解过程的认识与操控,生物质预处理技术,糖产量高的植物变种的选育,用于纤维素降解的酶和微生物的大规模筛选与选育等。除强调生物质能源开发的环境安全和公共健康的重要性之外,生物质能开发还需要解决生命周期评价(LCA)、可持续性的标准和指标的建立等问题。     

An assessment of oil supply and its implications for future prices

This paper examines three issues related to both the U.S. and world oil supply: (1) the nature of the long-term, postpeak production profile for the U.S. and, by inference, other regions (the Hubbert curve is used as a “strawman” model); (2) implications on U.S. energy security of using a modified Hubbert-type conceptual model of prepeak production, testing the adequacy of Latin America to be the primary source of U.S. oil imports; and (3) the cyclic behavior of oil prices. it shows that U.S. production will exhibit a more attenuated decline than that simulated by the Hubbert curve and not decline to zero. it asserts that U.S. production is better predicted by past reserves than past production, but that this argument does not apply to nations that keep a much larger proportion of reserves in the ground. Such nations could considerably expand production without any growth in reserves. The paper concedes that the potential total production for these nations could be examined with a Hubbert curve model linked to reserves, but with great uncertainty. Such an uncertain optimistic forecast predicts that the cumulative production of Latin America could far exceed that of the United States. Nevertheless, a statistical model of oil prices since 1870 implies that real wellhead oil prices in the United States are on a long-term upward path, underlying a much more “noisy” cyclical pattern estimated to include 22- and 27-year cycles. The statistical model predicts a severe oil shock within a few years (of 1998) but also predicts that through 2030, real oil prices will not reach 1981 levels again. The paper examines U.S. and world trends in seismic exploration, drilling locations and depths, drilling costs, oil/gas reserves, oil/gas use rates, and oil demand. After taking these factors into consideration, it concludes that the statistical model of oil prices cannot be disputed, despite its lack of basis in economic theory.     

Ethanol Fuels: Energy Balance, Economics, and Environmental Impacts Are Negative

Several studies suggest that the $1.4 billion in government subsidies are encouraging the ethanol program without substantial benefits to the U.S. economy. Large ethanol industries and a few U.S. government agencies, such as the USDA, support the production of ethanol. Corn-farmers receive minimal profits. In the U.S. ethanol system, considerably more energy, including high-grade fossil fuel, is required to produce ethanol than is available in the energy-ethanol output. Specifically about 29% more energy is used to produce a gallon of ethanol than the energy in a gallon of ethanol. Fossil energy powers corn production and the fermentation/distillation processes. Increasing subsidized ethanol production will take more feed from livestock production, and is estimated to currently cost consumers an additional $1 billion per year. Ethanol production increases environmental degradation. Corn production causes more total soil erosion than any other crop. Also, corn production uses more insecticides, herbicides, and nitrogen fertilizers than any other crop. All these factors degrade the agricultural and natural environment and contribute to water pollution and air pollution. Increasing the cost of food and diverting human food resources to the costly inefficient production of ethanol fuel raise major ethical questions. These occur at a time when more than half of the world's population is malnourished. The ethical priority for corn and other food crops should be for food and feed. Subsidized ethanol produced from U.S. corn is not a renewable energy source.     

论北极环境变化对中国国家非传统安全的影响

随着全球环境问题的升温,北极环境变化也越来越受到了国际社会的关注,中国作为一个近北极国家,深受北极环境变化的影响。本文从环境安全、经济安全、资源安全等非传统安全因素方面来探讨北极环境变化对中国可能产生的影响。就环境安全来说,北极环境变化对中国生态环境将产生直接的威胁,未来气温可能升高所导致北极海冰融化,对中国的社会和经济有着巨大危害;就经济安全而言,北极环境变化所带来的北极航道的全面开通,可能是中国未来发展的一个机遇,但是中国要想在北极航运资源的开发上分得一杯羹将面临着多重障碍;就资源安全来说,北极地区资源丰富,这对能源缺乏的中国而言,意义重大。但鉴于目前中国对北极问题的参与来看,即使北极地区的资源能得到良好的开发,其开发利用主要掌握在环北极国家手里,那么对能源供给越来越依赖国外的中国来说,必定会受制于人,无法从根本上保障中国能源供给的战略安全。     

Kansas Energy Sources: A Geological Review

Kansas produces both conventional energy (oil, gas, and coal) and nonconventional (coalbed gas, wind, hydropower, nuclear, geothermal, solar, and biofuels) and ranks the 22nd in state energy production in the U.S. Nonrenewable conventional petroleum is the most important energy source with nonrenewable, nonconventional coalbed methane gas becoming increasingly important. Many stratigraphic units produce oil and/or gas somewhere in the state with the exception of the Salina Basin in north-central Kansas. Coalbed methane is produced from shallow wells drilled into the thin coal units in southeastern Kansas. At present, only two surface coal mines are active in southeastern Kansas. Although Kansas has been a major exporter of energy in the past (it ranked first in oil production in 1916), now, it is an energy importer.     

Coal resources, new air quality standards,and sustainability

According to the National Research Council’s Committee on Earth Resources the stated goal of the “sustainability” paradigm is that the economic activity that maintains current well-being not make future generations worse off, either through environmental degradation or resource depletion. Coal is not “running out” in the United States but the effects of economic deregulation of electricity generation, new air quality standards (Phase II of the 1990 Clear Air Act Amendments), and continued restructuring of the coal mining industry will likely stretch lowsulfur coal supplies in the next decade. The paper discusses these forces and then presents summary coal quality data in the form of grade-cumulative tonnage relationships for major U.S. producing areas to show where future low-sulfur coal supplies are likely to come from. The final section considers the potential magnitude of additional demand for low-sulfur coal, alternative compliance strategies, and implications in terms of maintaining economic efficiency and in terms of the “sustainability paradigm.”     

美国对伊朗石油禁运与全球能源安全

2018年6月美国针对伊朗启动了史上最严厉的石油禁运政策,要求所有国家于11月停止从伊朗进口石油,否则相关国家和企业都将面临美国的经济制裁,并无意给予任何国家豁免权。当前,中国、日本、韩国、印度和欧盟等世界重要的石油进口国已经做出回应,除中国明确拒绝美国的单边制裁继续保持与伊朗的石油贸易外,其他主要石油进口国都大量削减从伊朗的石油进口。沙特阿拉伯等石油生产国也承诺通过石油增产来维护全球能源市场的稳定,以支持美国对伊朗的制裁。在经济全球化的大趋势下,美国对伊朗的石油禁运,势必引发全球能源市场的动荡,改变全球石油政治格局以及相关利益方的石油权益。这些方面会涉及到全球油价的波动、不同国家的石油安全与应对政策、世界能源贸易稳定与地缘政治格局的变动等。长期关注能源地缘政治的专家学者围绕美国对伊朗的石油禁运可能产生的影响发表观点,专家们认为美国此举是战略两难的困境,短期内对将会引起世界石油短缺及油价波动,甚至可能导致OPEC减产协议崩溃,改变世界主要进口国的进口规模以及来源结构,但对世界石油市场的长期影响有限。伊朗将寻求打折出售原油、替代港口出口以及多元化出口3条生存路径,目前最大的隐患是伊朗或将封锁霍尔木兹海峡,但是此举目前可能性不大。伊朗石油禁运具有长期性和复杂性,对中国既是机遇也是挑战,中国在“一带一路”倡议下与伊朗保持正常的石油贸易是双赢的选择,但需要谨慎对待由此引发的能源地缘政治的风险,提升能源安全应对的措施。期待各方观点对伊朗石油禁运引发的能源地缘政治格局以及中国的能源安全的解析,能够为相关政策制定者提供理论借鉴。     

90年代中国省级区域经济与环境协调度分析

在阐述经济环境协调度理论的基础上,建立了环境承载力与经济发展水平之间的协调度模型。并通过对90年代我国省级区域的实证分析,发现我国空间区域经济环境协调度基本符合“U”型曲线,区域经济发展模式大多以牺牲环境为代价,特别是中西部地区的问题比较严重。     

Estimation of the potential supply of U.S. oil by life cycle and learning models

Two methods of estimating potential U.S. oil supply are reported: life cycle analysis of updated (1987) oil production data, and an analysis based on learning curve modeling of discovery rates. Based on these analyses, potential U.S. (lower 48 plus Alaska) oil supply (ultimate recoverable oil) is estimated to be 222 billion barrels. A rough inference of the economic reference for this potential oil supply is an oil price of about $20/bbl (1989 dollars).