Ageing mallee eucalypt vegetation after fire : insights for successional trajectories in semi-arid mallee ecosystems

A critical requirement in the ecological management of fire is knowledge of the age-class distribution of the vegetation. Such knowledge is important because it underpins the distribution of ecological features important to plants and animals including retreat sites, food sources and foraging microhabitats. However, in many regions, knowledge of the age-class distribution of vegetation is severely constrained by the limited data available on fire history. Much fire-history mapping is restricted to post-1972 fires, following satellite imagery becoming widely available. To investigate fire history in the semi-arid Murray Mallee region in southern Australia, we developed regression models for six species of mallee eucalypt (Eucalyptus oleosa F.Muell. ex. Miq. subsp. oleosa, E. leptophylla F.Muell. ex. Miq., E. dumosa J. Oxley, E. costata subsp. murrayana L. A. S. Johnson & K. D. Hill, E. gracilis F.Muell. and E. socialis F.Muell. ex. Miq.) to quantify the relationship between mean stem diameter and stem age (indicated by fire-year) at sites of known time since fire. We then used these models to predict mean stem age, and thus infer fire-year, for sites where the time since fire was not known. Validation of the models with independent data revealed a highly significant correlation between the actual and predicted time since fire (r = 0.71, P < 0.001, n = 88), confirming the utility of this method for ageing stands of mallee eucalypt vegetation. Validation data suggest the models provide a conservative estimate of the age of a site (i.e. they may under-estimate the minimum age of sites >35 years since fire). Nevertheless, this approach enables examination of post-fire chronosequences in semi-arid mallee ecosystems to be extended from 35 years post-fire to over 100 years. The predicted ages identified for mallee stands imply a need for redefining what is meant by ‘old-growth’ mallee, and challenges current perceptions of an over-abundance of ‘long-unburnt’ mallee vegetation. Given the strong influence of fire on semi-arid mallee vegetation, this approach offers the potential for a better understanding of long-term successional dynamics and the status of biota in an ecosystem that encompasses more than 250 000 km² of southern Australia.

Fire management for biodiversity conservation : key research questions and our capacity to answer them

Knowing how species respond to fire regimes is essential for ecologically sustainable management. This axiom raises two important questions: (1) what knowledge is the most important to develop and (2) to what extent can current research methods deliver that knowledge? We identify three areas of required knowledge: (i) a mechanistic understanding of species’ responses to fire regimes; (ii) knowledge of how the spatial and temporal arrangement of fires influences the biota; and (iii) an understanding of interactions of fire regimes with other processes. We review the capacity of empirical research to address these knowledge gaps, and reveal many limitations. Manipulative experiments are limited by the number and scope of treatments that can be applied, natural experiments are limited by treatment availability and confounding factors, and longitudinal studies are difficult to maintain, particularly due to unplanned disturbance events. Simulation modelling is limited by the quality of the underlying empirical data and by uncertainty in how well model structure represents reality. Due to the constraints on large-scale, long-term research, the potential for management experiments to inform adaptive management is limited. Rather than simply recommending adaptive management, we define a research agenda to maximise the rate of learning in this difficult field. This includes measuring responses at a species level, building capacity to implement natural experiments, undertaking simulation modelling, and judicious application of experimental approaches. Developing ecologically sustainable fire management practices will require sustained research effort and a sophisticated research agenda based on carefully targeting appropriate methods to address critical management questions.

Resolving conflicts in fire management using decision theory: asset-protection versus biodiversity conservation

Agencies charged with nature conservation and protecting built-assets from fire face a policy dilemma because management that protects assets can have adverse impacts on biodiversity. Although conservation is often a policy goal, protecting built-assets usually takes precedence in fire management implementation. To make decisions that can better achieve both objectives, existing trade-offs must first be recognized, and then policies implemented to manage multiple objectives explicitly. We briefly review fire management actions that can conflict with biodiversity conservation. Through this review, we find that common management practices might not appreciably reduce the threat to built-assets but could have a large negative impact on biodiversity. We develop a framework based on decision theory that could be applied to minimize these conflicts. Critical to this approach is (1) the identification of the full range of management options and (2) obtaining data for evaluating the effectiveness of those options for achieving asset protection and conservation goals. This information can be used to compare explicitly the effectiveness of different management choices for conserving species and for protecting assets, given budget constraints. The challenge now is to gather data to quantify these trade-offs so that fire policy and practices can be better aligned with multiple objectives

Distribution, ecology and conservation of small mammals in fire-prone landscapes

Management of fire for biodiversity conservation is a global issue. This research provides new insights into the distribution of mammals in fire-prone eco-systems. A key outcome of this thesis is that understanding the role of fire over broad spatial scales and long time periods will benefit ecological and conservation management.

Changing the guard? China and the nuclear nonproliferation regime

China's profile in the nuclear nonproliferation regime is changing at a crucial time. The regime is under considerable internal and external strain as a result of eroding international support and trends in vertical and horizontal nuclear proliferation. While China's nonproliferation agenda and approach differ in some respects from those of other key actors, the gap separating China from the established drivers of efforts to address horizontal nuclear proliferation in terms of the objectives, institutions, and approach of the nonproliferation regime is diminishing, and there is considerable potential for China to contribute to the capacity of the regime to adapt to changing requirements. The Asia-Pacific region features both as the area of greatest nonproliferation concern to China and as the area where proliferation concerns are most likely to spur the further qualitative development of Chinese nonproliferation policy.

Fire and the conservation of the avifauna of mallee ecosystems

This research demonstrates that in mallee ecosystems the bird community changes with time-since-fire and is influenced by the spatial arrangement of landscape mosaics comprised of different post-fire-age vegetation. Fire alters vegetation structure and food availability for birds. The management of fire is critical for the conservation of mallee birds.

Fire, energy, and the ecology of reptiles in semi-arid Australia

‬Fire dependent ecosystems cover over half of the world's land surface. Understanding the factors that determine the distribution of fauna in these systems is essential to biodiversity conservation. This thesis explores the ecology of reptiles in a fire-prone region.

Simulation and visualization of fire using extended Lindenmayer systems

This research introduces a method of using Lindenmayer Systems to model the spreading and behavior of fire inside a factory building. The research investigates the use of L-System propagated fires for determining factors such as where the fire is most likely to spread first and how fast. It also looks at an alternative way of storing the Lindenmayer System, not in the form of a string but rather as a graph. A variation on the building and traversal process is also investigated, in which the L-System is traversed depth first instead of breadth first. Results of fire propagation are presented and we conclude that L-Systems are a suitable tool for fire propagation.

Reigniting the fire : a contemporary research agenda for social, political and nonprofit marketing

The paper reports on the core challenges faced by the nonprofit, political and social marketing disciplinary areas and suggests a series of research agendas to develop theory and practice to meet these challenges.

*

Social marketing's research agenda involves the continued adaptation of the new developments in commercial marketing, whilst building a base of social marketing theory and best practice benchmarks that can be used to identify, clarify and classify the boundaries of social marketing against social change techniques.
*

Nonprofit marketing is pursuing the dual research agenda of developing the theory and practice of social entrepreneurship whilst seeking deeper consumer-based research to understand motivations for charitable behaviour and gift giving.
*

Political Marketing's research agenda looks for an increase in the level of background research, core data and market research to use as a basis for developing more advanced theoretical and practical models. In addition, as political marketing is being transferred internationally between a range of political and electoral systems, there is a need for comparative research into both the relevance and effectiveness of these techniques to isolate nation independent and nation dependent political marketing strategies and campaigns.