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Aim To evaluate the influence of climate and Aboriginal landscape management on Holocene vegetation and fire activity. Location Flinders Island, Bass Strait, Tasmania where archaeological data document extended periods of human presence and absence over the past 12,000 years. Methods We evaluated climate-human-fire interactions through high-resolution pollen, charcoal and geochemical analyses of sediment cores from two wetland sites. Proxies for environmental change are qualitatively compared with archaeological data documenting Aboriginal occupation and later abandonment during the mid-Holocene. Results Warm and dry conditions of the early Holocene combined with anthropogenic ignitions promoted frequent fires that sustained highly fire-tolerant Eucalyptus savanna. During the mid-Holocene, when both temperatures and precipitation reached Holocene maxima, archaeological data suggest Aboriginal populations abandoned Flinders Island. At this time, Eucalyptus savanna was replaced by Casuarinaceae and broadleaf forests and fire activity decreased. The late Holocene was marked by a transition to increased incidence of intense fires that was associated with a shift from Casuarinaceae forests to xerophytic scrub dominated by Callitris rhomboidea, a conifer that is sensitive to frequent fires but regenerates well following infrequent fires. Main conclusions Palaeoenvironmental analyses from Flinders Island document significant shifts in fire regimes and vegetation types through the Holocene. In the early Holocene, Aboriginal landscape management played a key role in maintaining open Eucalyptus savanna, a prime habitat for marsupial prey species. Increasing aridity and strengthening of the El Niño Southern Oscillation climate mode during the mid to late Holocene contributed to the cessation of permanent human occupation and concomitant reduction of ignitions. Infrequent fire activity led to the dominance of xerophytes, especially Callitris, a genus adapted to drought and infrequent high-severity fires. This study highlights how climate change affects the persistence of human populations on islands and the capacity of human-set fires to create savanna habitats. [ABSTRACT FROM AUTHOR]

The persistence of treeless grasslands and sedgelands within a matrix of eucalypt and rainforest vegetation in the montane plateaux of northern Tasmania has long puzzled ecologists. Historical sources suggest that Tasmanian Aborigines were burning these treeless patches and models seeking to explain their maintenance generally include fire, soil properties and Aboriginal landscape burning. We aimed to provide a new historical perspective of the dynamics of the vegetation mosaics of Surrey Hills and Paradise Plains in north-west and north-east Tasmania, respectively, and used vegetation surveys and soil sampling to explore the role of vegetation and soils in these dynamics. Sequences of historical maps (1832 and 1903) and aerial photography showed that many treeless patches have persisted in the landscape since European settlement and that forests have rapidly expanded into the treeless patches since the early 1950s. Stand structure and floristic data described an expanding forest dominated by Leptospermum, which is consistent with vegetation succession models for the region. Soils under expanding forest boundaries did not have higher soil nitrogen or phosphorus than those under stable boundaries, signalling a lack of edaphic limitation to forest expansion. The magnitude of forest expansion at Paradise Plains (granite), Surrey Hills (basalt) and south-west Tasmania (quartzite) appears to follow a nutrient availability gradient and this hypothesis is backed by differences in soil phosphorus capital between the three systems. Given that existing vegetation boundaries in northern Tasmania do not coincide with soil nutrient gradients, we suggest that treeless vegetation was maintained by Aboriginal landscape burning and that the recent contraction of treeless vegetation is related to the breakdown of these fire regimes following European settlement. The observed rates of forest expansion could result in a substantial loss of these grasslands if sustained through this century and therefore our work supports the continuation of prescribed burning to maintain this high conservation value ecosystem. [ABSTRACT FROM AUTHOR]

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The article discusses the importance of dendrochronology to land manager, fire ecologist and global change biologist in order to date the past fire events which are manifested by injuries on the trunks on long-lived trees. It states that dendrochronology traces the fire scars or records of past landscape fire activity with unparalleled temporal resolution. Global climate change is also a factor that easily acquires fire data and understanding the relationship with interannual and multidecadal climate cycles.

The article focuses on the importance of understanding fire ecology. This understanding includes the direct and indirect effects of fire disturbance on plants and animals. Aside from ecology, another science disciplines are investigating the impact of landscape fire disturbance on hydrological systems as part of the emerging field of ecohydrology. An understanding on the effects of landscape fire on ecohydrological systems is needed especially with the threat of global environmental changes including the increased frequency and intensity of landscape fires.

Provides an overview on a fire ecology research that has emphasize the importance of the landscape scale. Benefits of satellite imagery to fire ecologists; Study of fire patterns in southern African savannas which emphasize the importance of land management; Importance of climate and fire management influencing fire activity.

One of the most complex and contentious issues in Australian ecology concerns the environmental impact of Aboriginal landscape burning. This issue is not only important for the development of a comprehensive understanding of the dynamics and evolution of the Australian biota, but is central to the formulation of appropriate strategies for the conservation of the nation's biodiversity. Ethnographic evidence leaves little doubt that Aboriginal burning played a central role in the maintenance of the landscapes subsequently colonized by Europeans. Both 19th century European colonists and anthropologists in the 20th century documented the indispensability of fire as a tool in traditional Aboriginal economies, which have aptly been described as 'fire-stick farming'. Aborigines used fire to achieve short-term outcomes such as providing favourable habitats for herbivores or increasing the local abundance of food plants, but it is not clear whether or not Aborigines had a predictive ecological knowledge of the long-term consequences of their use of fire. A large body of ecological evidence suggests that Aboriginal burning resulted in substantial changes in the geographic range and demographic structure of many vegetation types. Aboriginal burning was important in creating habitat mosaics that favoured the abundance of some mammal species and in the maintenance of infrequently burnt habitats upon which the survival of specialized fauna depends. Aboriginal fire regimes were probably critical for the maintenance of at least one species of tree (Callitris intratropica) in the monsoon tropics. The question of the original impact of humans on the Australian environment is fundamentally speculative because of vague, disputed time frames proposed for the waves of colonization and shifting settlement patterns of Aborigines in the late Quaternary period. There is an inherent circular argument concerning the cause and effect of climatic change, vegetation change, and burning through the late Quaternary. Charcoal and pollen evidence from long sedimentary cores is ambiguous and cannot be used to demonstrate unequivocally the initial impact of Aboriginal people on the landscape of Pleistocene Australia. The sparse available evidence does not support the hypotheses that Aboriginal burning was primarily responsible for the extinction of Pleistocene megafauna; was critical for the maintenance of habitats of small mammals that have become extinct following European colonization; initiated widespread accelerated soil erosion rates in either the Pleistocene or Holocene; or forced the evolutionary diversification of the Australian biota. Burning may have caused the extinction of some fire-sensitive species of plants and animals dependent upon infrequently burnt habitats, and it must have maintained structurally open vegetation such as grasslands and also extended the range of fire-adapted species, such as Eucalyptus, into environments climatically suitable for rain forest. Palaeoecological research concerning prior impacts of Aborigines must give way to focused studies of the role of different anthropogenic fire regimes in contemporary ecosystems that have not been destroyed by European colonization. Such research is crucial for comprehending the role of Aboriginal burning in the maintenance of Australia's unique, rich biodiversity. [ABSTRACT FROM AUTHOR]