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91.
Wildfires are widely reviewed as key inputs to Mediterranean ecosystems. However, research is often flawed by major biases. (1) The approach adopted by most planners focusing on forest fires dismisses the human dimension of fire as a component of agricultural production systems. (2) The Wildland–Urban Interface (WUI) concept postulates that cities and wildlands/wildfires are, and should remain, worlds apart, a statement whose truth is increasingly questioned by recent disastrous “urban wildfires”. (3) The Mediterranean Basin as a fire-prone area is all the more fantasized, as it is almost never studied as a whole.The present paper takes a critical view of city–wildland/wildfire interrelationships through a large-scale study of the Mediterranean Basin based on MODIS MCD12Q1 (Land Cover Type) and MCD45A1 (Burned Area Product) data collected between 2001 and 2013. The Mediterranean is an ideal place to investigate, as its human-dominated and urbanized landscapes are known to be extremely vulnerable to fire hazards. Data processing reveals that (wild)fires and cities maintain indissoluble ties, as if both elements could not be considered mutually exclusive on a geographical basis. Urban sprawl, reduced rural autonomies, changes in forest covers, old agricultural practices, and military conflicts provide the framework for an extended mitigation process challenging the WUI concept as a space divider. 相似文献
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基于人地关系的旅游地理学理论透视与学术创新 总被引：13，自引：6，他引：7
针对旅游地理学理论研究比较薄弱和研究内容相对泛化的现状,提出将旅游人地关系作为旅游地理学研究的核心,阐述了旅游人地关系的理论内涵,认为旅游地理学是研究地球表层人类旅游活动与地理环境关系并服务于人类生活和社会经济发展的一门科学,其研究对象是"旅游地域系统"。基于人地关系的理论视角,按照旅游地理学理论体系化和科学化的发展要求,充分考虑旅游地理学旅游性、区域性、综合性和应用性的学科属性,初步构建了以旅游活动系统和地理环境系统为基础,以人地关系理论为核心,融合相关学科理论的旅游地理学理论框架。论文还梳理了旅游地理学的基本研究内容、主要科学问题和重要研究方法,强调应大力倡导地理学科学精神,改变低水平应用导向和过于偏重技术导向的研究现状,切实运用旅游地理学研究和解决国家与地方旅游发展中的重要现实问题,并在此基础上强化理论导向的思想型研究,将深刻揭示旅游人地关系地域系统的基本特征、功能结构、时空演化、基本规律、动力机制和调控途径作为旅游地理学研究的重点,通过学科特色创新、研究范式创新、理论成果创新、研究方法创新和应用价值创新,推动旅游地理学理论研究的深化、学术水平的提高和学科体系的完善,促进现代旅游地理学的本土化和中国旅游地理研究的国际化。 相似文献
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Over the last decade, cap-and-trade emissions schemes have emerged as one of the favoured policy instruments for reducing GHG emissions. An inherent design feature of cap-and-trade schemes is that, once the cap on emissions has been set, no additional reductions beyond this level can be provided by the actions of those individuals, organizations and governments within the covered sectors. Thus, the emissions cap constitutes an emissions floor. This feature has been claimed by some to have undesirable implications, in that it discourages ethically motivated mitigation actions and preempts the possibility that local, state and national governments can take additional mitigation action in the context of weak national or regional targets. These criticisms have become prominent in Australia and the US within the public debate regarding the adoption of an emissions trading scheme (ETS). These criticisms and their potential solutions are reviewed. A set-aside reserve is proposed to automatically retire ETS permits, which would correspond to verified and additional emissions reductions. This minimizes the possibility that ethically motivated mitigation actions are discouraged, allows for additional action by other levels of government, while providing transparency to other market participants on the level of permit retirements. 相似文献
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Julia Scharwächter Andreas Eckart Susanne Pfalzner Jens Zuther Melanie Krips Eva Schinnerer Johannes Staguhn 《Astrophysics and Space Science》2005,295(1-2):101-106
I Zw 1 and 3C 48 are two neighboring template objects at a later stage of the hypothesized merger-driven evolutionary sequence from ultra-luminous infrared galaxies (ULIRGs) to quasi-stellar objects (QSOs). Since galaxy mergers are assumed to trigger the evolution, it is important to confirm the merger properties of transitionary objects. Using multi-wavelength observations and N-body simulations, the merger histories of I Zw 1 and 3C 48 have been investigated in two separate case studies. Here, the results from both studies are compared and their relevance for the evolutionary hypothesis is discussed.This research is partly based on observations with ISAAC at the Very Large Telescope (VLT) of the European Southern Observatory (ESO) under projects 67.B-0009 and 67.B-0019. 相似文献