Economic Potential of Biomass Based Fuels for Greenhouse Gas Emission Mitigation

Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass, hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing, andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices. At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent. At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon prices above $70,biofuels dominate all other agriculturalmitigation strategies.     

湖南八大公山国家级自然保护区国家重点保护和珍稀濒危植物区系分析

从属和种的水平上分析了八大公山国家级自然保护区国家重点保护和珍稀濒危植物的区系成分特点。结果表明,该保护区共有国家重点保护和珍稀濒危植物31科44属53种。其中有国务院1999年8月4日批准公布的I级重点保护植物4科4属6种,II级重点保护植物18科23属29种;有《中国珍稀濒危保护植物名录》(1987)和《中国植物红皮书》所列的濒危植物2科2属2种,稀有植物14科15属16种,渐危植物15科19属20种。其区系具有由亚热带植物区系向温带植物区系过渡,但热带性质比较明显的特点,而且中国特有成份是该区系中非常重要的组成部分。     

Carbon and energy prices under uncertainty: A theoretical analysis of fuel switching with heterogenous power plants

European power producers have a major influence on the EU ETS, given that both their CO₂ emissions and their EUA (European Union Allowance) allocations account for more than half of the total volumes of the scheme. Fuel switching is often considered as the main short-term abatement measure under the EU ETS. It consists in substituting combined cycle gas turbines (CCGTs) for hard-coal plants in power generation. Thereby coal plants run for shorter periods, and CO₂ emissions are reduced. This paper provides the first theoretical analysis of fuel switching, in a context where power plants involved are not equally efficient. We begin with a preliminary work using illustrative examples and sensitivity analyses, which enables us to observe how differences in the efficiency of power plants impact the cost of fuel switching, and how this is related to the level of switching effort. Based on this, we build a theoretical model taking into account the effect of differences in the efficiency of power plants involved in fuel switching. We also investigate the effect of the timing of fuel switching abatements, within the temporally defined environment of our dynamic model. Results demonstrate that the gas price and uncontrolled CO₂ emissions act together on the carbon price. We show that the influence of the gas price on the carbon price depends on the level of uncontrolled CO₂ emissions, due to heterogeneity of power plants that are used in the fuel switching process. Furthermore, we show that the time of occurrence of uncontrolled emissions matters so that shocks have a stronger impact when they occur in a period that is closed to the end of the phase.     

Impacts of land-cover change on the water flow regulation ecosystem service: Invasive alien plants,fire and their policy implications

Land and water resource issues typically fall under separate governance systems. For example, agricultural policy regulates land-cover change while water departments regulate water quality. However, land-use changes can directly affect water resources. Water flow regulation is a key service which is affected by changes in land-cover but its dynamics are poorly understood by most policy makers and land management organisations. We simulated and quantified the effects of plant invasions on land-cover, hydrological soil characteristics and catchment responsiveness on flow regulation using a hydrological model. The case study was located in the indigenous fynbos shrublands in South Africa. Fynbos requires fire to regenerate, has moderate biomass, occurs mostly in areas with a potential to erode and is prone to invasion by woody plant species, particularly trees. Invasions can affect flow regulation by changing community structure and function and increasing fuel loads. The greater fuel load increases fire intensity and severity which, in turn, changes the hydrological responses of catchments. Few studies have assessed the effects of invasion on hydrological responses but studies on plantations have recorded significant increases in soil water repellence following fire, resulting in increased overland flow similar to impacts of fires in invaded areas. Simulation of clear-felling of pines and different degrees of water repellency increased both the responsiveness of the catchment to rainfall and extreme rainfall events. The simulated fire effects were consistent with other studies of hydrological responses to fire. Our study indicates that invasions of pines and acacias in the study area could substantially increase the risk of flood damage even from moderate rainfall events, and highlights the importance of maintaining flow regulation capacity. New policy approaches are required which take account of the linkages and interactions between land-use choices, water resources and ecosystem services, and address them when considering governance arrangements.     

Devising an electronically supported heritage conservation method for the Valley of Flowers in the Indian Himalayas

The Valley of Flowers is a national park in the Himalayan state of Uttarakhand in India that was classified as a world natural heritage site in 1988. Around 1982, its maximum carrying capacity was fixed at 60 persons per day, which has been called excessive by experts and observers, given the extremely fragile and immensely valuable nature of the Valley's heritage. This, in monetary terms, can be put at millions of dollars, and is considerably more viewed in terms of knowledge of breeding medicinal plants in cold climates that are being affected by climate change, which its microclimate and ecology present. Given the state's poor resources and the fact that tourism is one of the most important industries for development and conservation, this research assesses the heritage value of the Valley and develops a programme for conservation, including a computerised program for permits, whose value can easily be raised from the current paltry Rs 150 per person. Accompanied by fallow periods and marketing through the Internet to aim for educated tourists, the program ensures that the maximum carrying capacity of the Valley is never exceeded, thus spreading out the number of tourists over its 3.5-month season, while allowing flexibility in booking for chance groups and small families that can pay more.     

环境约束下中国省域旅游经济效率及其影响因素的空间计量分析

采用Super-SBM方法将环境因素作为非期望产出纳入旅游经济效率测算框架,结合空间计量经济方法分析2005—2016年我国省域旅游经济效率空间关联性及影响因素溢出效应,结果显示:环境约束下,我国省域旅游经济具有一定的空间集聚趋势,呈现出"东南热、西北冷"的分布特征,尚未实现网状结构均衡发展;我国省际旅游经济效率间存在显著的空间溢出作用。对于环境约束下旅游经济效率发展来说,人均GDP、技术创新、市场化、环境规制均有显著的正向作用,路网密度作用不显著,外国直接投资(FDI)有显著的负向作用。影响因素的溢出效应来看,市场化、经济增长、技术创新具有显著的积极间接溢出效应,但环境规制带来了显著的负向间接溢出效应,FDI与路网密度的间接溢出效应不显著。     

我国农业野生植物资源原生境保护区建设现状、问题及未来的思考

我国农业野生植物原生境面临着环境污染、人类农业生产、经济社会发展以及各类违法活动的侵蚀和破坏,建立原生境保护区是保护农业野生植物资源的重要途径之一。基于对当前威胁我国农业野生植物原生境面临的四大因素(自然灾害、农业活动、经济发展、违法活动)的系统梳理的基础上,探讨了现有农业野生植物原生境保护区建设的法规政策体系以及保护区建设现状和存在的主要问题,在此基础上提出了加强保护区建设的几点建议。分析结果表明,当前我国农业野生植物保护区建设存在的主要问题包括:保护区土地权属界定、保护区建设内容限定过窄、忽视保护区管理机构能力建设、对保护区周边农民权益保护不够。为了提高保护区建设工作,文章建议相关部门应该重视以下几个问题:统筹协调行业部门之间的权属差异,重视农业野生植物异位保存工作,修订完善保护区建设技术规范,兼顾保护区民众利益。     

河南云台山药用植物种质资源研究

目的：系统调查研究河南云台山药用植物资源状况。方法：通过野外实地调查、民间访查、室内标本鉴定、建立凭证标本以及参考相关文献,对云台山药用植物种质资源状况进行研究。结果：云台山有药用植物共计91科,250属,359种,约占河南药用植物的18.29%;根据药用植物的分布特点将其分为北部中低山区、南部丘陵区和平原区。结论：首次系统报道四大怀药之乡河南云台山药用植物资源数字资料,对云台山药用植物种质资源未来的研究工作提出建议。     

美丽的宿根花卉-鸢尾科植物

介绍了鸢尾科植物的种群分布,各个品种的生长特征,观赏特性以及它们在园林绿化、水土保持中的应用。     

美国商业核电站监管的进化与发展——基于美国核能监管委员会的发展史

通过分析研究美国从原子能委员会到核能监管委员会的演化进程,并运用实证分析手段解析引发核电监管机构进化的事件及背后的推动因素、监管机构的独立性和权力制衡的制度设计,使我们了解到:美国核能监管委员会是美国特定的政治、经济、文化环境下的产物,有其独特性;核能监管委员会的外部制约及内部约束机制,在保障其独立、公开、专业履行职责的同时,形成了行业安全至上的文化,建立起基于公信力的监管权威。进一步告诉我们,对核电完善的监督,尤其是消费者、公众和媒体对被监管者生产的产品和服务的监督,是防止核电监管失灵的最有效措施。