可再生能源的现状和前景(下)

论述了可再生能源的定义、分类和特性。分析了促进可再生能源发展的驱动力有油价上涨、减排温室气体的压力、市场推动、高技术产业的国际竞争、政府的激励政策等。综述了中国和世界开发利用生物质能、水能、风能、太阳能和地热的现状和发展前景,认为我国在未来15年内可再生能源建设将空前增加。     

基于SWOT-PEST模型的广西农业生物质能产业发展研究

本文运用SWOT-PEST相融合的分析法,对广西农业生物质能产业发展的内部优劣势与外部环境的机会和挑战四方面进行了详细的分析,总结出广西农业生物质能产业面临的形势和所处的地位,提出了相应的发展策略。     

生物质热裂解液化技术的发展概况

生物质能转换利用技术包括直接燃烧技术、热化学转化技术和生化转化技术.生物质热化学转化技术具有效率高、成本低的优势,备受各国关注,而热裂解液化技术又是研究中的重中之重,是目前生物质能源发展领域中的前沿技术之一.目前,生物质热裂解液化技术在美国、加拿大等国的研究开发居世界领先地位,而我国在这方面的研究起步较晚,没有商业化生产和应用.由于生物质资源具有可再生性,其必将取代原有的矿物能源,因此生物质热裂解液化技术具有广阔的发展应用前景.     

生物质能源开发利用对“三农”的影响分析

对农业而言,生物质能开发利用能够促进我国农业结构升级、改善农业经济管理模型、发展林业经济。对农村而言,生物质能开发利用能够改善农村能源结构,优化农村生态环境和生活环境,促进农村工业发展。对农民而言,生物质能开发利用能够增加就业机会,增加农民收入,提高农民生活质量。然而,开发生物质能有可能增加对生产资料的竞争,增加相关农林产品价格的波动以及由于大面积种植单一作物而降低生物多样性,因此开发利用生物质能要合理规划。     

国际生物质能源发展的评价——动机、支持措施及对世界粮食供求影响视角

发展生物质能源是应对国际能源危机的重要途径。但各国生物质能源战略的出发点却似乎并不在于此。从动机看,美欧等发达国家的真正动机更像是抢占世界可再生能源市场,而巴西等少数发展中国家的核心动机则在于规避农产品贸易保护、改变与发达国家的斗争形式和斗争领域。从支持与保护措施看,它是农产品贸易大国推行农业支持与农产品贸易保护的一种特殊形式。扭曲的动机和支持与保护措施使得生物质能源的发展对世界粮食供求产生了重要的影响,并进一步恶化了广大发展中国家的经济发展环境。     

木质生物质的生物炼制及其综合利用

随着世界经济的高速发展,近年来能源资源短缺、生态环境恶化等问题日益严重。生物炼制是环境可持续发展和能源经济转变的重要手段,以生物炼制为核心的生物技术将能为解决人类社会目前面临的资源、能源与环境等诸多重要问题提供支撑。木质生物质是世界上产量最丰富的可再生生物资源,有巨大的发展潜力。介绍了生物炼制的概念,主要阐述了木质生物质生物炼制技术和主要的生物质化学品,生物质材料,生物质能源等,并展望了生物炼制的发展前景。     

论能源植物的定义及其评价指标体系的建立

本文探讨并总结了能源植物的定义,认为能源植物是指具有较高合成能源或替代能源产品能力的植物,并根据用途分为4类:1.富含类似石油成分的能源植物;2.富含高糖、高淀粉和纤维素等碳水化合物或者碳氢化合物的能源植物;3.富含油脂和挥发油的能源植物;4.速生丰产薪炭植物。根据不同能源植物的类型建立了3个评价指标体系,分别是:1.富含油、淀粉、糖、橡胶等类能源植物评价指标体系;2.木质纤维素能源植物评价指标体系;3.薪炭能源植物评价指标体系,筛选出3个一级指标:能源含量、生物质产量和生态适应性。通过数据实践检验,表明建立的评价指标体系可基本满足能源植物筛选工作的需要。     

Changing decisions in a changing landscape: How might forest owners in an urbanizing region respond to emerging bioenergy markets?

The global bioenergy market has considerable impacts on local land use patterns, including landscapes in the Southeastern United States where increased demand for bioenergy feedstocks in the form of woody biomass is likely to affect the management and availability of forest resources. Despite extensive research investigating the productivity and impacts of different bioenergy feedstocks, relatively few studies have assessed the preferences of private landowners, who control the majority of forests in the eastern U.S., to harvest biomass for the bioenergy market. To better understand contingent behaviors given emerging biomass markets, we administered a stated preference experiment to private forest owners in the rapidly urbanizing Charlotte Metropolitan region. Respondents indicated their preferences for harvesting woody biomass under a set of hypothetical market-based scenarios with varying forest management plans and levels of economic return. Our analytical framework also incorporated data from a previously-administered revealed preference survey and spatially-explicit remote sensing data, enabling us to analyze how individuals’ ownership characteristics, their emotional connection the forests they manage, and the spatial patterns of nearby land uses, influence willingness to grow bioenergy feedstocks. We found conditional support for feedstock production, even among woodland owners with no history of active management. Landowners preferred higher economic returns for each management plan. However low-intensity harvest options were always preferred to more intensive management alternatives regardless of economic return, suggesting that these landowners may be more strongly motivated by aesthetic or quality-of-life concerns than feedstock revenues. Our analysis indicated preferences were dependent upon individual and environmental characteristics, with younger, more rural landowners significantly more interested in growing feedstocks relative to their older and more urban counterparts. While this study focuses on one small sample of urban forest owners, our results do suggest that policy makers and resource managers can better inform stand-level decision-making by understanding how feedstock production preferences vary across populations.     

Heterogeneity and assessment uncertainties in forest characteristics and biomass carbon stocks: Important considerations for climate mitigation policies

The management of forests to store carbon and mitigate climate change has received significant international attention during the last decade. Using in situ data from a 2008–2009 forest inventory field campaign in Sri Lanka, this study describes the structural characteristics and carbon stocks of six natural forest types. This paper has a dual scope: i) to highlight the variation in carbon stored in aboveground biomass within and between forest types and ii) to determine the implications of the allometric equations chosen to calculate biomass carbon stocks. This study concerns work related to climate change interventions, such as Reducing Emissions from Deforestation and Forest Degradation (REDD+) and other forest-related, performance-based initiatives that require proper monitoring, reporting, and verification of carbon stocks, sinks and emissions. The results revealed that forests are heterogeneous in terms of tree density and height–diameter relationships, both between and within the six forest types investigated. The mean aboveground carbon stock in the different forest types ranged from 22 to 181 Mg C ha⁻¹, and there were statistically significant differences in the carbon stocks of the six forest types in 7 of 15 cases. The estimated carbon stock depended heavily on the allometric equation used for the calculations, the variables, and its application to the specific life zone. Due to the diversity of forest structures, these results suggest that caution should be taken when applying default values to estimate forest carbon stocks and emission values in reporting and accounting schemes. The results also indicated the need for allometric equations that are context-specific for different forest types. Therefore, new field investigations and measurements are needed to determine these specific allometric equations, as well as the potential variation in forest carbon stocks in tropical natural forests.     

遥感技术在青海刚察县草畜平衡研究中的应用

［目的］刚察县草地资源丰富，是青海省环湖重点牧区之一，文章利用遥感技术对刚察县草地生物量进行了遥感估算，并在此基础上分析其载畜平衡状况，以期为刚察县草地资源利用、生态环境保护和区域经济可持续发展提供参考依据。［方法］利用2016—2018年刚察县的遥感数据、地面样方调查数据进行生物量估算，并利用牧业统计数据计算载畜平衡指标，在此基础上分析其载畜平衡状况。［结果］（1）指数函数可以较好地模拟NDVI与生物量之间的相关关系，指数方程为：y=60137e093x（R2=066）。（2）2015年植被生物量较2010年有所增加，而2018年平均生物量较2010年持平，这一特征主要与气候和降水条件有关，2018年降水量较少、气候较干旱。2015年冬春草场生物量较2010年基本持平，2018年较2010年有下浮下降； 2015年和2018年夏秋草场比2010年均有小幅提高。（3）基于遥感估算的草地生物量结果和刚察县的补饲情况进行了草畜平衡情况分析，结果显示，2010年超载率为2308%，为超载； 2011年超载率为511%，2015—2017年分别为602%、690%、929%，均为草畜平衡。［结论］草畜平衡政策实施后，刚察县在减少草原可利用面积后，通过补饲减缓了天然草场的载畜压力，天然草场基本达到草畜平衡，有利于该区域草地生态环境的恢复和保护。