The Victorian Bushfires of 2002–03 and the Politics of Blame: a Discourse Analysis

This paper identifies contrasting environmental discourses on bushfire from the public debate that followed the Victorian fires of 2002–03. Submissions to the inquiry into the 2002–03 Victorian bushfires provide a particularly rich source of documentation. It is argued that environmental events such as bushfire only become political issues, or problems, when they are constituted as such through environmental discourse. Through the analysis, three contrasting discourses on bushfire are identified—here labelled the ‘conservationist’, ‘ruralist’ and ‘wise use’ discourses. In examining how different ‘constructions’ of bushfire have led to conflict, each discourse is shown to consist of a range of actors who draw on shared storylines. Having established a better understanding of the different attitudes, beliefs, interests and values that underpin debates about bushfire, the paper concludes with a brief discussion of the prospects for compromise among the discourses and the potential for improved land and fire management outcomes.     

Characteristics and genesis of maghemite in Chinese loess and paleosols: Mechanism for magnetic susceptibility enhancement in paleosols

Morphological characteristics and microstructures of magnetic minerals extracted from Chinese loess and paleosols were investigated using powder X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Our results indicate that maghemite in loess–paleosol sequences was transformed from magnetite through oxidation of magnetite. Maghemite transformed from eolian magnetite during chemical weathering has low-angle grain boundaries among maghemite nano-crystals. Some nano-crystalline maghemites with nanoporous texture resulted from microbe-induced precipitation of magnetite or transformation of poorly crystalline ferric Fe (oxy)hydroxides in presence of Fe-reducing bacteria. Aggregates of euhedral maghemite nano-crystals were transformed from magnetite magnetosomes. Both microbe-induced nanoporous magnetite and microbe-produced magnetite magnetosomes are directly related to microbial activities and pedogenesis of the paleosols. It is proposed that the formation of nano-crystalline maghemite with superparamagnetic property in paleosol results in the enhancement of magnetic susceptibility, although the total amount (weight percent) of magnetic minerals in both paleosol and loess units is similar. Our results also show that nano-crystalline and nanoporous magnetite grains prefer to transform into maghemite in semi-arid soil environments instead of hematite, although hematite is a thermodynamically stable phase. This result also indicates that a decrease in crystal size will increase stability of maghemite. It is also inferred that surface energy of maghemite is lower than that of hematite.     

Mineralogical changes during thermal demagnetization of natural continental sandstones

We study the mineralogical changes suffered by specimens of natural miocene red and green continental sandstones (from Pozuelos Formation and Tiomayo Formation) cropping out in the Argentine Puna that increase their bulk magnetic susceptibility and change color when thermally treated. We hypothesize that on heating siderite, which is present in small quantities as cement in the studied sandstones, would oxidize and decompose into maghemite and/or magnetite. Subsequent heating to higher temperatures sometimes would bring about the conversion of maghemite and/or magnetite to hematite. Mössbauer spectroscopy proved to be a very valuable tool for the determination of the presence of siderite in small amounts in the studied samples. The present results show that further work is needed in order to fully understand the mineralogical changes suffered by continental sandstones during heating. The characterization of such changes occurred during laboratory routines is relevant, since they can help to better understand natural processes.     

The Quantitative Identification of Regional Mine and Natural Earthquakes and Its Application

INTRODUCTIONThe structural mine earthquake in coal mines refers to the quake induced by excavationengineeringthatleadstorupturingor change of geological structure and weakness surfaceintheinteriorof rock mass.According to the origin,mine earthquakes can b…     

‘Committing to Place’ at the Local Scale: the potential of youth education programs for promoting community participation in regional natural resource management

Emerging approaches to environmental governance require a greater level of community participation than did previous approaches in which these responsibilities largely rested with government agencies. There is consequently a need for increased engagement with NRM among a broad community sector. This paper examines initiatives by two prominent government agencies, the Murray–Darling Basin Commission (MDBC) and the National Museum of Australia (NMA), to engage school children from regional communities using education programs that focus on place and environmental health. We focus on the MDBC's International Riverhealth Conference held in Mildura in 2003 and the associated Murray–Darling Basin TalkBack Classroom sponsored by the NMA and the Parliamentary Education Office (PEO). We explore how key themes of local scale, place-based identities, youth voice and critical engagement are developed in these programs and consider how they relate to the environmental agency of children. We then reflect on the potential for the kinds of environmental agency promoted through these programs to help build the capacity of local communities to progress larger goals of environmental restoration and sustainability in the Murray–Darling Basin. The evaluation research reported here forms part of the Committing to Place research project, an Australian Research Council Linkage grant involving the University of Tasmania, the National Museum of Australia and the Murray–Darling Basin Commission.     

喀斯特地区旅游开发的自然景观保护--以贵州省绥阳县为例

该文以贵州省绥阳县为例，针对我国西南喀斯特地区旅游开发中自然环境的特点，探讨溶洞景观的保护、喀斯特地表生态环境保护、水体的保护与综合治理等问题。     

三江并流世界自然遗产地旅游地质景观成景地质作用初步分析

三江并流世界自然遗产地丰富独特的旅游地质景观是多种地质作用与不同成景岩组交互叠加作用的结果。其发育的地层基础主要为碳酸盐成景岩组、变质岩成景岩组、碎屑岩成景岩组以及岩浆岩成景岩组等,典型内力成景地质作用为板块缝合作用、断裂成景作用、变质成景作用,外力作用则主要有河流、冰川、丹霞、地热、喀斯特作用等。     

生态城市的内涵及建设策略

生态城市是通过倡导生态理念，采用生态技术，建立生态化产业体系，从而达到社会、经济、环境的可持续发展，实现自然生态平衡、人文生态和谐的城乡统一体。从可持续发展的角度出发，利用生态学和社会学的观点，论述生态城市的内涵，提出科学的城市规划、合理的城市评价指标体系、完善的城市管理制度是实现生态城市的前提，强调只有自然生态、人文生态两手抓才能真正实现经济、社会、环境全面发展。     

Material selection for the gas containment system of a compressed natural gas carrier fleet

In this work, the possible exploitation of fiber-reinforced composites in the context of maritime transportation of compressed natural gas (CNG) is investigated. In addition to a more conventional steel configuration, two different fiber materials, carbon and glass, are considered as construction materials for pressure vessels (PVs) to be stored on board ships, with thickness optimized by FEM analysis.The considered scenario is represented by the transportation of CNG from an offshore well to a terminal on shore. Fleets of ships carrying CNG in pressure vessels manufactured with the investigated materials are generated by means of a ship synthesis model (SSM) software and compared on the basis of technical and economical indicators.The choice of the construction material influences considerably the weight of the PVs, which represent a major item of total ship weight and reflects directly on the general transport performances in terms of resistance, seakeeping and reliability in the service. On the other hand, capital as well as operating expenditures are considerably affected by the choice. When exploring the design space, the ship synthesis model is able, at a preliminary stage of the design, to account for the various technical and economical aspects, their implications and relationships. Results are presented of computations carried out in a specific case, identified by the annual gas production and other characteristics of the well terminal and a cruising route for the ships. The comparison is carried out on the basis of the cost per transported unit of gas and of the percentage of success in the transportation process. The computations show that the choice of the PV material has a key influence on the results in terms of optimal number, dimensions and speed of the ships.