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Forest fires release substantial amounts of carbon (C). Much of it is emitted to the atmosphere, but some is deposited within ash on the ground. Little is known about amount and types of C deposited in ash. Here, we quantify total C, and total inorganic, water-soluble and particulate organic fractions deposited in ash during the catastrophic 2009 'Black Saturday' wildfires in Australia. These fires coincided with the highest air temperatures and lowest humidity ever recorded in the local area, which, combined with high fuel loads of mostly long unburnt eucalypt forests, generated extreme burning conditions. In three mixed-species eucalypt forest sites sampled, the canopy, understorey and litter fuels were almost completely consumed, resulting in substantial ash deposition (mean, 81.9 t ha), with 5.9 t ha of C being transferred from vegetation to the forest floor. In five temperate rainforest sites sampled, the canopy was not burnt and ash deposition was lower (mean, 48.3 t ha) than in the mixed-species eucalypt forest, but overall their higher C content resulted in higher C deposition (8.1 t ha). In all cases, most C contained in ash was organic and its pyrogenic nature infers increased resistance to degradation. Pyrogenic C is viewed by many as an important C sink, which could contribute to long-term C sequestration when incorporated into soils or sediments. Our results highlight the potential importance of the pyrogenic C pool in freshly deposited ash and, therefore, the necessity of a systematic and detailed analysis of ash deposition and C forms in ash to improve our understanding of C fluxes by forest fires. [ABSTRACT FROM AUTHOR]

Few investigations link post-fire changes to sediment sources and erosion processes with sediment yield response at the catchment scale. This linkage is essential if downstream impacts on sediment transport after fire are to be understood in the context of fire effects across different forest environments. In this study, we quantify changing source contributions to fine sediment (<63 µm) exported from a eucalypt forest catchment (136 ha) burnt by wildfire. The study catchment is one of a pair of research catchments located in the East Kiewa River valley in southeastern Australia that have been the subject of a research program investigating wildfire effects on runoff, erosion, and catchment sediment/nutrient exports. This previous research provided the opportunity to couple insights gained from a range of measurement techniques with the application of fallout radionuclides 137Cs and 210Pbex to trace sediment sources. It was found that hillslope surface erosion dominated exports throughout the 3·5-year post-fire measurement period. During this time there was a pronounced decline in the proportional surface contribution from close to 100% in the first six months to 58% in the fourth year after fire. Over the study period, hillslope surface sources accounted for 93% of the fine sediment yield from the burnt catchment. The largest decline in the hillslope contribution occurred between the first and second years after fire, which corresponded with the previously reported large decline in sediment yield, breakdown of water repellency in burnt soils, substantial reduction in hillslope erodibility, and rapid surface vegetation recovery. Coupling the information on sediment sources with hillslope process measurements indicated that only a small proportion of slopes contributed sediment to the catchment outlet, with material derived from near-channel areas dominating the post-fire catchment sediment yield response. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This article reviews the history of military reserves in Australia with particular reference to the Army Reserve. It shows how the importance of reserves in Australia has waxed and waned across the past two centuries, from an early situation of primacy in the colonial period. The importance of reserves has reemerged in the post–Cold War era, with new forms of reserve organization evolving alongside ‘‘conventional’’ reserve forces. The authors discuss the extent to which these developments need to be accompanied by attention to cultural and personnel management issues and to enhanced reserves–regular integration. Despite the challenge of juggling civilian employment with reserve commitments, most reservists appear to welcome a greater, rather than a token, obligation to serve. There is a viable and meaningful role for the reserves provided that the Australian Defence Force and the government are prepared to devote sufficient effort to them and to assign them appropriate tasks. [ABSTRACT FROM PUBLISHER]

The effect of prescribed fire on suspended sediment and nutrient exports was investigated in two small Eucalyptus forest catchments in south-eastern Australia. In 2005, a patchy, mostly low-severity prescribed fire was applied to both catchments, followed in 2006 by a second burn applied to riparian areas of one catchment, with the other catchment utilised as a control for this burn. Historic pre-fire weekly stream water sampling was combined with post-fire weekly and storm-based sampling to quantify the effect of the fires. The 2005 fire resulted in a significant difference (P = 0.000) in suspended sediment concentrations compared to pre-fire data and generated peak study period suspended sediment (11.5 kg ha-1 year-1) and total phosphorous (0.016kg ha-1 year-1) exports under near-average rainfall. However, peak suspended sediment exports only slightly exceeded the average annual load from a nearby undisturbed catchment. Well-below-average rainfall in 2006 resulted in lower exports after this burn compared with the 2005 fire. The results highlighted the importance of hydrological conditions for suspended sediment and nutrient exports within the first 12-18 months after prescribed fires, beyond which generally rapid surface vegetation recovery is likely to mitigate any burns effects. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the suspended sediment concentration (SSC) and discharge (Q) hysteresis patterns of two nested upland catchments in Central Tablelands region of New South Wales. It notes that monitoring of sediment flux, measuring of sediment yield, and mapping of incised channels supplemented the analysis of SSC-Q hysteresis. It implies the significant of study in between-scale linkage of dominant process as well as in sediment delivery processes.

The article discusses the suspended sediment loads and delivery estimation in Southeastern Australia. It states that upland headwater catchments in the country underwent extensive erosion that removed large amounts of sediments to lowlands. It also suggests that upland areas may continue to dominate fine sediment loads in lowland rivers and that the suspended sediment may be delivered to downstream reaches under average rainfall conditions. Meanwhile, it notes that a better understanding of sediment transfer through upland headwater catchments may have implications for interpreting downstream sediment supply.

This paper describes a new approach to youth participation and development used by a youth organization in the West Kimberley region of Western Australia. It offers an account of how people from isolated communities in the north of Australia organize bush trips, or what they call "back to country" trips, to bring together the young, elders, and other community members. Not only is this used as a means to have young people "participate" more fully in the life and experience of their community, but it also leads to a range of other events including young people's participation in land care, cultural education, fire management, science and economic development. This story offers a rich example of the multiple benefits of combining intergenerational contact, practical activities and the opportunity to "return to country" to practice Indigenous lore and custom and involve young people more fully in the life of their community. It also demonstrates how important land-based activity, traditional culture, walking and other forms of physical animation are to youth participation with Indigenous young people. [ABSTRACT FROM AUTHOR]

On 27 June 2000, the Howard Government released a public information paper on defence which set in train a process of public consultation in which the people's views were sought on a range of defence and defence-related issues. This paper examines why the Government chose to go to the people, how and by whom the community consultation was conducted, who was consulted and listened to, and how what was heard at the public meetings component of the process was both interpreted and reported. The paper concludes that the public consultation process was more about politics than policy; it is inappropriate for the Government to claim or imply that it has heard from the 'Australian people' or even 'the majority of the community' on the issues raised; and the consultation process and its outcomes are not entirely risk-free for the Government and the defence establishment. [ABSTRACT FROM AUTHOR]

In the last two decades, as the likelihood of involvement in major military conflict appears to have diminished, the Australian Defence Force has reflected changes in Australian society in a number of areas. These includes (1) the ethnic composition of the ADF; (2) the institution/occupation orientation of service personnel; (3) the admission of women to a wider range of roles; (4) the enactment of a law permitting selective conscientious objection; and (5) the government's decision to allow homosexuals to serve in the Defence Force. This study provides a brief historical background before outlining the principal factors that have brought about change in these areas. Some of these changes have been painful for the Defence Force while others have proved relatively painless. What they all have in common, however, is a focus on the rights of individuals. This raises the question as to their impact on military effectiveness and the limits of individual rights in the armed forces, especially at a time of diminished military threat. [ABSTRACT FROM AUTHOR]

Examines the principles and issues relating to the use of the Australian defense force in the enforcement of law against individual citizens and aliens. Pressures for the extension of the police function to the armed forces; Restraints in the employment of the armed forces; Political, legal and constitutional principles governing the armed forces.

Abstract: Numerous reports of “flash floods”, “mud torrents” and “landslides” in burnt landscapes of south-east Australia were only recently linked to debris flows and recognised as a significant process that warrant more detailed investigation. This paper provides a systematic documentation of high-magnitude erosion events after wildfire in south-east Australia, focusing on small (<5km2), upland catchments in eastern Victoria that were burnt by wildfire between 2003 and 2009. The aims of the study were to i) collect and show evidence of debris flow occurrence after wildfire; ii) quantify erosion rates from debris flows and; iii) identify rainfall thresholds and key hydrological properties. The result showed that 13 out of the 16 recorded high-magnitude erosion events were runoff generated debris flows. These occurred in dry eucalypt forests burnt at high or very high severity in steep headwater catchments throughout the eastern uplands of Victoria. The debris flows were triggered by intense, short duration rainfall events (I 30 35–59mmh−1) with annual exceedance probability in the order of 20%. This is the first paper to document the occurrence of post-fire runoff generated debris flows in Australia, so the discussion draws on literature from the western USA, where a large body of research has been dedicated to evaluating the risk posed by post-fire debris flows and their role in landscape processes. Typical features common to both systems include low infiltration capacity of burnt catchments; widespread sheet erosion and levee lined rills on steep upper hillslopes; and severe channel erosion initiated in response to convergent flow in previously un-scoured drainage lines. The depth of sheet erosion on surveyed slopes in the upper catchments (4.6±0.96 mm to 18.4±2.7mm) indicates that hillslope material provides an important source of sediment. The average channel entrainment rate of three debris flows ranged from 0.6 to 1.4m3 m−1. Runoff generated debris flows were not recorded in wet or damp forest types suggesting that this process is unlikely to operate in these forest environments. One isolated case of mass failure generated debris flow was recorded in wet forest. The outcome of the study indicates that runoff generated debris flows in dry eucalypt forest are an important process to be considered during post-fire risk assessment of hydrological hazards. [Copyright &y& Elsevier]