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Wildfires, not logging, cause landscape traps
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... Indeed, the tall eucalypt forest ecosystem has evolved with particular regimes of both low and high intensity fires. However, if a severe fire is followed by another severe fire within the space of a few decades then a demographic shift is possible, potentially resulting in the replacement of tall eucalypt forest (Ashton 1981) with relatively short-lived tree and shrub communities adapted to more frequent fire (Ferguson and Cheney 2011;Lindenmayer et al. 2011a). ...
... This may lead to reduced investment in harvesting, haulage and log processing capacity and could reduce the value of production and level of employment in the industry (ABARES 2011). Worryingly, these predictions of a gradual decline in forest growth and productivity do not take into account the projected increase in the frequency of intense fires in these flammable systems (Hennessy et al. 2006;Cary et al. 2012) which may lead to abrupt losses of large areas of tall eucalypt forests Ferguson and Cheney 2011;Lindenmayer et al. 2011a). ...
Tall eucalypt forests are iconic ecosystems renowned for the great height, high biomass and rapid growth rates of the trees that grow within them. These forests are highly valued for their biodiversity, timber production and social values. In the past, these values have been threatened by land clearing for agriculture, but now the most threatening processes come from unsustainable timber harvesting practices and changes in the fire regimes that characterise these forests. Tall eucalypt forests have been the focus of many research initiatives largely focused on understanding disturbance ecology and the impacts of timber harvesting on a range of forest values. The four core studies presented here reveal trends in fungi, birds, arboreal marsupials, vascular plants, invertebrates and tree growth in tall eucalypt forests and the way that various silvicultural treatments, fire events and climate drivers influence these trends. An analysis of tree growth from over 1000 permanent inventory plots distributed across Australia indicated that tree growth in tall eucalypt forests is related to a range of climatic variables. Predictive models based on these relationships infer a decrease in tree growth under various climate change scenarios. Plot networks in the Mountain Ash and Alpine Ash forests of Victoria revealed highly idiosyncratic temporal changes in populations of arboreal marsupials and birds, particularly after the 2009 wildfires. Long-term monitoring of birds, fungi, beetles and vascular plants in harvested and unharvested forest plots have informed forest management practices in the forests of southern Tasmania and southwestern Australia. All of the plot networks presented in this chapter have been important in documenting trends beyond those which the plot networks were originally designed to detect. However, despite well over 25 years of dedicated research in these systems, the trends identified represent a preliminary understanding of environmental change in these ecosystems that operate on temporal scales of months to centuries. As such, ongoing monitoring of current plot networks and the establishment of well-designed new plot networks in tall eucalypt forests is imperative to properly inform sustainable forest management
... These authors found that young stands of E. regnans were more likely to be affected by high-severity fires than older stands, as predicted by the landscape trap model. This finding led them to conclude that logging in E. regnans forests is increasing the risk of abrupt state change, a view that has been disputed by some forest managers (Ferguson & Cheney, 2011). ...
... The strong extrinsic effect of fire weather, regardless of stand age, in E. delegatensis forests (Fig. 3) is consistent with the analysis by Price & Bradstock (2012) of the 2009 Victorian fires using the same remotely sensed estimates of fire severity as used in our study. Those authors found that under extreme fire weather conditions, high-severity fires occurred in Eucalyptus forests regardless of past disturbance history, supporting the observations of Ferguson & Cheney (2011) who argue that fire intensity and rate of spread depend more on terrain and weather than on fuels. A Figure 3 Empirically derived variation in the probability of a fire being of high severity (scorching the canopy), and probably stand-replacing, in Eucalyptus delegatensis forest, in response to fire weather (forest fire danger index). ...
Forests that regenerate exclusively from seed following high-severity fire are particularly vulnerable to local extinction if fire frequency leaves insufficient time for regenerating plants to reach sexual maturity. We evaluate the relative importance of extrinsic (such as fire weather and climate cycles) and intrinsic (such as proneness to fire due to stand age and structural development) factors in driving the decline of obligate seeder forests. We illustrate this using obligate seeding alpine ash (Eucalyptus delegatensis) forests in the montane regions of Victoria, Australia, that were burnt by megafires in 2003 (142,256 ha) or 2007 (79,902 ha), including some twice-burnt areas (11,599 ha). Geospatial analyses showed only a small effect of stand age on the remote sensing estimates of crown defoliation, but a substantial effect of forest fire weather, as measured by forest fire danger index (FFDI). Analysis of meteorological data over the last century showed that 5-year increases in FFDI precede cycle major fires in the E. delegatensis forests. Such strong extrinsic climate/weather driving of high-severity fires is consistent with the 'interval squeeze model' that postulates the vulnerability of obligate seeder forests to landscape-scale demographic collapse in response to worsening fire weather under climate change.
... Climate change has recently sharpened the focus on understanding the risk of short-interval fire for ash forests, and a number of frameworks have recently been developed to conceptualise these risks. Two recent developments have been the 'landscape trap' (Lindenmayer et al., 2011) and the 'interval squeeze' models -the former postulates that 'intrinsic' stand-level factors like fuel load and disturbance influence the risk of decline of ash forests; while the latter emphasises 'extrinsic' factors like fire weather and climate (also supported by Ferguson and Cheney, 2011). Bowman et al. (2016) attempted to reconcile these two theories, concluding that recent patterns of fire in the Victorian alps lend support to the 'interval squeeze' model, though they did note a minor role of stand-level factors such as stand age. ...
Record-breaking fire seasons in many regions across the globe raise important questions about plant community responses to shifting fire regimes (i.e., changing fire frequency, severity, and seasonality). Here, we examine the impacts of climate-driven shifts in fire regimes on vegetation communities, and likely responses to fire coinciding with severe drought, heatwaves and/or insect outbreaks. We present scenario-based conceptual models on how overlapping disturbance events and shifting fire regimes interact differently to limit post-fire resprouting and recruitment capacity. We demonstrate that, although many communities will remain resilient to changing fire regimes in the short-term, longer-term changes to vegetation structure, demography and species composition are likely, with a range of subsequent effects on ecosystem function. Resprouting species are likely to be most resilient to changing fire regimes. However, even these species are susceptible if exposed to repeated short-interval fire in combination with other stressors. Post-fire recruitment is highly vulnerable to increased fire frequency, particularly as climatic limitations on propagule availability intensify. Prediction of community responses to fire under climate change will be greatly improved by addressing knowledge gaps on how overlapping disturbances and climate change-induced shifts in fire regime affect post-fire resprouting, recruitment, growth rates, and species-level adaptation capacity.
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... There has been considerable debate about disturbance-related changes in flammability in the Mountain Ash (Eucalyptus regnans)-dominated wet sclerophyll forests of southeastern Australia , Ferguson and Cheney 2011, Attiwill et al. 2014, Taylor et al. 2014a. These forests support infrequent, large, intense wildfires (Murphy et al. 2013) that have resulted in major losses of life and property (Griffiths 2001, Cruz et al. 2012, Blanchi et al. 2014. ...
There are multiple pathways for vegetation to change following disturbances. Understanding those post‐disturbance pathways is critical for managing wildfire risk since vegetation is fuel in a wildfire context. Across forest systems, there is considerable debate about disturbance‐related changes to fuels and flammability. This study investigated post‐disturbance fuel trajectories following three disturbance types—high severity wildfire, low severity wildfire, and clear‐fell logging. Fuels were measured in a chrono‐sequence of 141 sites in Mountain Ash (Eucalyptus regnans)‐dominated wet sclerophyll forest in southeastern Australia, a particularly contentious forest system. Wildfires are an important part of the lifecycle of these forests, but too frequent fire can threaten post‐fire regeneration. Large wildfires (in 2009, 1983 and 1939) and ongoing public and scientific debate over clear‐fell logging highlight the need to better understand post‐disturbance trajectories for fuel and flammability in wet sclerophyll forests. We used empirical data to test 10, sometimes contradictory, hypotheses from the scientific literature regarding post‐disturbance pathways for fuel following wildfire and logging. Only five hypotheses were supported with surface fine fuels, fuel hazard, species composition, and vertical structure driving overall differences in post‐disturbance fuel trajectories. The implications for flammability remain uncertain because the independent and interactive effects of many fuel components on overall flammability remain unquantified. Importantly, we found there were always high quantities of fuel, irrespective of disturbance history, which demonstrates that fire occurrence is not fuel‐limited in wet sclerophyll forests. Under conditions of abundant fuel, fuel moisture could become critical to fire occurrence. Therefore, forest management should prioritize efforts to quantify not only the importance of individual fuel components to flammability but also fuel moisture dynamics in wet sclerophyll forests. As the climate (and fuels) becomes drier under climate change, it will be a major challenge to manage fire regimes in these highly valued forests.
... There has been increasing debate in the literature on whether human disturbance through timber harvesting has altered interactions between wildfire and wet sclerophyll forests, resulting in more widespread fire outbreaks. Some studies support the hypothesis that timber harvesting increases fire risk and severity (Lindenmayer, 2010;Lindenmayer et al., 2011Lindenmayer et al., , 2009) and others oppose (Attiwill and Adams, 2013;Attiwill et al., 2014;Ferguson and Cheney, 2011). ...
In this study, we characterised the temporal-spectral patterns associated with identifying acute-severity disturbances and low-severity disturbances between 1985 and 2011 with the objective to test whether different disturbance agents within these categories can be identified with annual Landsat time series data. We analysed a representative State forest within the Central Highlands which has been exposed to a range of disturbances over the last 30 years, including timber harvesting (clearfell, selective and thinning) and fire (wildfire and prescribed burning). We fitted spectral time series models to annual normal burn ratio (NBR) and Tasseled Cap Indices (TCI), from which we extracted a range of disturbance and recovery metrics. With these metrics, three hierarchical random forest models were trained to 1) distinguish acute-severity disturbances from low-severity disturbances; 2a) attribute the disturbance agents most likely within the acute-severity class; 2b) and attribute the disturbance agents most likely within the low-severity class. Disturbance types (acute severity and low-severity) were successfully mapped with an overall accuracy of 72.9 %, and the individual disturbance types were successfully attributed with overall accuracies ranging from 53.2 % to 64.3 %. Low-severity disturbance agents were successfully mapped with an overall accuracy of 80.2 %, and individual agents were successfully attributed with overall accuracies ranging from 25.5 % to 95.1. Acute-severity disturbance agents were successfully mapped with an overall accuracy of 95.4 %, and individual agents were successfully attributed with overall accuracies ranging from 94.2 % to 95.2 %. Spectral metrics describing the disturbance magnitude were more important for distinguishing the disturbance agents than the post-disturbance response slope. Spectral changes associated with planned burning disturbances had generally lower magnitudes than selective harvesting. This study demonstrates the potential of landsat time series mapping for fire and timber harvesting disturbances at the agent level and highlights the need for distinguishing between agents to fully capture their impacts on ecosystem processes.
... There has been increasing debate in the literature on whether human disturbance through timber harvesting has altered interactions between wildfire and wet sclerophyll forests, resulting in more widespread fire outbreaks. Some studies support the hypothesis that timber harvesting increases fire risk and severity (Lindenmayer, 2010; Lindenmayer et al., 2011 Lindenmayer et al., , 2009) and others oppose (Attiwill and Adams, 2013; Attiwill et al., 2014; Ferguson and Cheney, 2011). In Victoria, the most comprehensive disturbance information at the landscape level is found in the State Fire History Database (SFHD) (Department of Environment Land Water and Planning, 2015a) and the State Logging History Database (SLHD) (Department of Environment Land Water and Planning, 2015b). ...
In this study, we characterised the temporal-spectral patterns associated with identifying acute-severity disturbances and low-severity disturbances between 1985 and 2011 with the objective to test whether different disturbance agents within these categories can be identified with annual Landsat time series data. We analysed a representative State forest within the Central Highlands which has been exposed to a range of disturbances over the last 30 years, including timber harvesting (clearfell, selective and thinning) and fire (wildfire and prescribed burning). We fitted spectral time series models to annual normal burn ratio (NBR) and Tasseled Cap Indices (TCI), from which we extracted a range of disturbance and recovery metrics. With these metrics, three hierarchical random forest models were trained to 1) distinguish acute-severity disturbances from low-severity disturbances; 2a) attribute the disturbance agents most likely within the acute-severity class; 2b) and attribute the disturbance agents most likely within the low-severity class. Disturbance types (acute severity and low-severity) were successfully mapped with an overall accuracy of 72.9 %, and the individual disturbance types were successfully attributed with overall accuracies ranging from 53.2 % to 64.3 %. Low-severity disturbance agents were successfully mapped with an overall accuracy of 80.2 %, and individual agents were successfully attributed with overall accuracies ranging from 25.5 % to 95.1. Acute-severity disturbance agents were successfully mapped with an overall accuracy of 95.4 %, and individual agents were successfully attributed with overall accuracies ranging from 94.2 % to 95.2 %. Spectral metrics describing the disturbance magnitude were more important for distinguishing the disturbance agents than the post-disturbance response slope. Spectral changes associated with planned burning disturbances had generally lower magnitudes than selective harvesting. This study demonstrates the potential of landsat time series mapping for fire and timber harvesting disturbances at the agent level and highlights the need for distinguishing between agents to fully capture their impacts on ecosystem processes.
... Lindenmayer et al. (2011) detailed a regime shift of old growth ash forests to young fire-susceptible forests unable to reach maturity due to effects of fire and timber harvesting. Debate is polarised between conservationists and foresters regarding the causes of landscape traps (Ferguson and Cheney 2011;Attiwill et al. 2014). ...
In regions prone to wildfire, a major driver of ecosystem change is increased frequency and intensity of fire events caused by a warming, drying climate. Uncertainty over the nature and extent of change creates challenges for how to manage ecosystems subject to altered structure and function under climate change. Using montane forests in south-eastern Australia as a case study, we addressed this issue by developing an ecosystem state-and-transition model based on a synthesis of expert knowledge and published data, with fire frequency and intensity as drivers. We then used four steps to determine future adaptation options: (1) estimation of changes in ecosystem services under each ecosystem state to identify adaptation services: the ecosystem processes and services that help people adapt to environmental change; (2) identification and sequencing of decision points to maintain each ecosystem state or allow transition to an alternative state; (3) analysis of interactions between societal values, scientific and management knowledge and institutional rules (vrk) required to reframe the decision context for future management, and (4) determining options for an adaptation pathway for management of montane forests under climate change. Our approach is transferable to other ecosystems for which alternative states can be predicted under climate change.
The vulnerability to repeated high severity fires of tall wet eucalypt forests (TWEF) dominated by obligate seeder species is widely understood. However, 80% of Tasmania’s TWEF are dominated by resprouter species, and while these forests are more resilient to wildfire than those dominated by obligate seeders, the degree of their resilience is not well documented. Recently, two wildfires affected five 1-ha forest plots that had been previously measured, providing the opportunity to assess fire effects on these forest stands. We characterised these wildfires using remote sensing and field measurements of char height (a proxy for fire intensity) and canopy scorch (fire severity). We assessed the influence of tree diameter, fire intensity and seedling densities on the survival and resprouting responses of eucalypt overstorey trees and mixed species understorey trees. Our results showed that these fires were predominantly of low to moderate intensity and severity. Our results showed that mature TWEF were resilient to these wildfires, with overall eucalypt survival of 75%. The major eucalypt species were either mostly not defoliated (E. regnans), or could recover rapidly by epicormic resprouting (E. delegatensis and E. obliqua). Results from this and other studies show recovery from topkill caused by high severity fires occurs but is slower, by basal resprouting (E. obliqua) or from seed (all species). By contrast, understorey species suffered high mortality (85% overall), with few species showing substantial resprouting. Fire resistance in both groups increased markedly with tree diameter.
Our results have implications for forest management. The high survival of overstorey eucalypts leads to a multi-aged stand structure in most unlogged old growth TWEF in Tasmania. On the other hand, clearfell logging, originally designed to mimic stand replacing wildfire in obligate seeder systems, creates a vulnerable, even aged stand of young regrowth, and at a landscape scale, it also reduces average tree size, reducing overall resistance to fire. Adopting alternatives to clearfelling, such as partial logging systems, will increase landscape resilience to fire, as well as providing other previously shown benefits.
Eucalyptus delegatensis is native to the Australian Alps (subsp. delegatensis) and montane Tasmania (subsp. tasmaniensis). Post-fire regeneration mechanisms of the obligate-seeder subspecies on the Australian mainland are well-known, but less is known about the resprouter Tasmanian subspecies. In January 2016, large tracts of Eucalyptus delegatensis forests in central Tasmania, logged at different intensities, were burnt by low- and high-severity fire. We used statistical modelling to understand how tree survival, vegetative regeneration and seedling recruitment differed according to understorey type, fire severity, logging intensity and tree size (DBH). Fire severity, defined as unburnt, low-severity (fire scarring on the stem and/or lower canopy burnt) and high-severity (full canopy burnt), affected tree survival: 84% of trees were alive in unburnt transects, compared with 43% in low-severity transects and 36% in high-severity transects. Epicormic resprouting was the dominant mode of vegetative recovery, with < 1% of total trees recovering solely by basal resprouting. Fire severity significantly affected epicormic resprouting, with 70% of live stems resprouting post-fire in low-severity transects and 99% in high-severity transects, compared with 4% in unburnt transects. Tree survival was strongly influenced by tree size: in high-severity transects, 24% of trees with DBH < 20 cm were alive, compared with 88% of trees with DBH ≥ 20 cm. These differences in survival were primarily because large trees were more likely to resprout epicormically, with epicormic shoots present on 24% of live trees with DBH < 20 cm, compared with 79% of live trees with DBH ≥ 80 cm. The strong effect of tree size renders clear-felled forests especially vulnerable to fire during the several decades when all the regenerating trees are small (DBH < 20 cm). Seedling recruitment was uncommon, independent of understorey type and logging intensity, but with higher occurrence on high-severity (54%) than low-severity (19%) or unburnt (15%) transects. When present, seedling densities were typically low: median = 400 and maximum = 4·10⁴ seedlings ha⁻¹. This study highlights that mature forests of Eucalyptus delegatensis in Tasmania are more resilient (able to return to pre-disturbance conditions) to single high-severity fires than their mainland counterparts, because they can recover more quickly through epicormic resprouting. However, clear-felling reduces this resilience for several decades because it decreases median tree size and, hence, leads to higher post-fire mortality. It is difficult to predict how the Tasmanian subspecies will respond to an increased frequency of high-severity fires associated with a projected warmer and drier climate.
Aspects of the scientific discipline of forestry have endured decades of environmental activism aimed at discrediting it. Much of this activism has entailed strategic avoidance of inconvenient truths while promoting myths, half-truths and pseudo-science as though they are absolute fact. However, arguably of greater concern are more recent instances of false or unsupported claims about native forest management contained in some conservation-focussed research published in peer-reviewed scientific journals.
This paper examines recent scientific literature which addresses Leadbeater’s possum and broader conservation issues in the forests of Victoria’s Central Highlands. In assessing its contribution to the public and political discourse on forest management we identified the following six areas where much of this research is contentious:
• Leadbeater’s possum population estimates
• The proportions of forests respectively catering for conservation or wood production
• Value of active forest management strategies for conserving Leadbeater’s possum
• Forest carbon stocks
• The concept of ecosystem collapse
• Value of environmental services derived from native forests.
This contentious research is characterised by the omission of critically important context, reliance on flawed or wrong assumptions and errant citation practices. In the past, there would have been an expectation of such problems being identified and excluded during effective peer review by appropriate scientists. That this is no longer guaranteed is indicative of broken academic protocols.
We conclude that there is evidence of a disturbing synergy between some peer-reviewed science and environmental activism in fashioning and promoting a questionable case for forest management change—in this instance, through advocacy of a proposed new national park that would restrict or end a range of public activities and decimate a significant and sustainable local timber industry.
The conceptual bases for sustainable forest management and the ecosystem approach to sustainable forest management will soon be considered in international forums on forests and biological diversity. Considerable national activity in both conservation and the sustainable management and use of forests has occurred over the last decade in Australia, leading to the unification of both concepts. The principles and operational guidelines of the ecosystem approach have been effectively incorporated into the concept of ecologically sustainable forest management under the National Forest Policy Statement, and now underpin Australia's Regional Forest Agreements. This paper explores these concepts and demonstrates how they have been adapted and incorporated into Australian forest management under Regional Forest Agreement processes.
In 1949 the area of mature Eucalyptus regnans F.Muell¹ (the Big Ash) on the Hume Range, Victoria, was a largely even-aged 230-year-old forest with a component of the overstorey derived from a fire in 1851. Subsequent fires have resulted in patchy regeneration where suitable gaps in the overstorey were present. In 1949 three main types of the understorey were present: type A, mature Pomaderris aspera; type B, dense immature Pomaderris aspera; and type C, coppiced Olearia argophylla and Bedfordia arborescens. In type A, ground fern was patchy and statistically correlated with patches of lower density Pomaderris aspera. Over a period of 48 years the eucalypt overstorey has been depleted by death and windthrow while understorey trees and shrubs have been severely damaged by sporadic heavy snowfalls and insect and fungal attack. The type A understorey is now showing signs of changing to Olearia argophylla dominance and the cover of ground fern and tree fern strata has doubled to more than 80% over this period in spite of damage caused by infrequent, but severe, droughts. The type B understorey is now mature and resembles type A, while the type C understorey shows invasion by Pomaderris aspera and regeneration of Olearia argophylla. No successful establishment of E. regnans has occurred. The rainforest in the gullies consists of alternating patches of forest and tree fern groves, the latter, together with rotting logs and upthrown root balls, providing niches for rainforest tree establishment. In swampy flats of Leptospermum grandifolium on the plateau Atherosperma moschatum is becoming increasingly dominant. Atherosperma moschatum is also invading mature understorey adjacent to riparian communities. This species and Olearia argophylla may constitute the final stage of the long secondary succession after fire in the Big Ash area. However, the Hume Range is adjacent to drier foothills and plains to the north, west and south. Whether the Big Ash will be spared from fire in future centuries is very doubtful.
Old-growth forests in south eastern Australia are important for biodiversity conservation, recreation, carbon storage, social values and, to a declining extent, for timber production. Developing a comprehensive definition of old-growth forest that can apply across all Australian vegetation types has been challenging. Old growth can be viewed from ecological and social perspectives. For policy and management purposes old growth has been defined as a growth stage in forest development, incorporating ecological maturity and lack of evidence of past disturbance. Classification and assessment of old growth has largely been restricted to those areas covered by regional forest agreements (RFAs) between different states and the Federal Government. Old growth can be impacted by wildfire, timber harvesting, insect pests, diseases and other disturbances. Climate change will also present challenges for the future management of old-growth forests. There is increasing scientific understanding of the relationships between species, forest growth stage and old-growth forest attributes. To meet biodiversity conservation objectives, the management focus is shifting from assessing and protecting old-growth forests, to providing for forests across the landscape with old-growth attributes. This approach may be at odds with other conceptions of old growth based on notions of undisturbed systems free of human influence.
Regional Forest Agreements between the Australian Commonwealth and State governments have fulfilled a number of key requirements for achieving ecologically sustainable development and management of Australia's forests. Examples are the establishment of a world class system of conservation reserves; a secure resource base for the timber industry with increased opportunities for industry development and investment; and the establishment of management systems and processes for ecologically sustainable forest management. Ten Agreements have been signed representing twenty-year plans for commercial forest regions in four Australian States. Science played a major role in these Agreements and contributed significantly to their success. Scientific assessments, information and advice covered a wide range of economic, social, environmental and heritage values. Scientific development and application of robust databases and analytical tools facilitated important land use and management decisions where balanced outcomes between competing forest uses and values were sought within limited time frames. We review the process for developing Regional Forest Agreements as part of Australia's approach to national and international ecologically sustainable development obligations, and the application of science and scientifically-based approaches and frameworks for determining conservation, sustainable management and industry development outcomes.
The article provides an overview of the regional assessment and agreement process which is being conducted by the Commonwealth (i.e. federal) and State governments in the major forest regions of Australia. The context of the dominant position of the State in Australian forest management and its consequences are introduced. The acrimonious environmental conflicts over the use of the forests and the difficulties of resolving them led to a national forest policy in 1992 and joint Commonwealth-State regional planning. The processes of regional assessment are described and the difficulties of their hurried execution noted. The inter-governmental agreements which resulted reflect a remarkable transfer of Commonwealth environmental interests to the States and the apparent disabling of its environmental legislation for the forest sector in the regions concerned. They also reflect an apparent intention to maintain and improve the standard of environmental management.
To incorporate models of wildlife habitat into an AI environment, an understanding of niche and habitat theory is essential. Using our understanding of habitat of arboreal marsupials, the authors illustrate how the theory is used in the development of expert systems and decision support systems. For the purpose of forest planning and management of wildlife, habitat has to be thought of at different scales of resolutions. There is a need to move between scales and extrapolate with confidence from location-specific data to non-inventories sites, both spatially and through time. Lessons learned from experience are discussed in terms of incorporating wildlife habitat into the Australian national forest inventory. -from Authors
Wildlife management is becoming increasingly important in Australian forestry and this paper presents the conceptual framework for a relevant wildlife management strategy. Wildlife management in Australian forests might best be co-ordinated nationally. Because of the changing public perceptions of the role forestry must play in wildlife management in native forest, suggestions are made for the modification of present practice which will benefit both timber and wildlife management. The paper also reviews information requirements, the issues and the concerns important in the determination of such a strategy. Information bases are necessary for sound forest wildlife management. The concepts of minimum viable population and optimum habitat are discussed as well as wildlife management design in terms of zoning and the two integrated methods of core population and dispersed population techniques. It is argued that the standards of forest management have to improve to achieve the necessary balance between timber production and wildlife management. This will require an understanding of the aforementioned two concepts and the options available for integrating wildlife and timber management. Priority should be given to the determination of optimum habitat of species, forest site classification and the ranking of wildlife species according to management need.
A 'forest practices system' is the broader regulatory framework for the delivery of a code of forest practices. Various approaches are taken by different States within Australia, reflecting differences in factors such as the proportion of operations within the public and private sectors, the type of forest operations, institutional arrangements within government, social attitudes and the availability of skills and resources in both the government and private sectors. The key components of a forest practices system are discussed, with particular reference to codes that regulate operations within native forests. The regulatory approach adopted under a forest practices system should aim to foster co-operation among stakeholders, optimise the use of available skills and resources and minimise bureaucracy. The effectiveness and credibility of any system will ultimately depend upon its having clear objectives and standards, provision for continuing improvement, and transparent processes for monitoring and reporting outcomes.
This paper addresses management and policy issues arising from the 2009 and other recent fires that burnt the iconic ash-type forests of eastern Victoria. After sketching a general framework for an analysis of sustainability, the paper elaborates the results of a simulation study on seed collection and storage (to be published separately), especially in relation to the risks posed to the ash-type state forests by major fires. These forest types are notably fire sensitive and easily killed by fires of moderate or even mild intensity. They are also cyclical in the extent of seed production and do not set seed in commercial quantities for the first 20 years of life. If seed collection and storage is restricted to ?low? levels until 2050, the risks are substantial, involving probabilities over 90% for alpine ash, implying insufficient seed to permit artificial regeneration of those burnt areas that have not regenerated naturally, whether climate change occurs or not. Those risks can be reduced substantially by higher levels of seed collection, but even at ?median? levels the probabilities may approach 40% under high rates of climate change. The simulated outcomes for mountain ash state forests are much less severe but the impacts of high rates of climate change are still great enough to cause discomfort.
Data for the ash-type conservation reserves were not available but descriptive reports indicate that the risks for both forest types in the conservation reserves may be very high, as many of the old-growth stands in the national parks (often closed water catchments) were severely burnt in the 2003, 2006?2007 or 2009 fires. The risks posed by fire in the next 20 y to water quality and biodiversity are very likely to be material.
This leads to advocacy of active management measures that include: (1) a well-equipped workforce, (2) removal and salvage of fire-killed trees along access roads, (3) seed collection and artificial regeneration in conservation reserves, (4) strategic swaps of age classes to the advantage of both tenures, (5) regrowth thinning for habitat management and water production, (6) better access for fire management and more fuel reduction burning and (7) strategic orientation of harvest areas.
In the past, the conservation versus development debate about forests has been a ?zero-sum game?. Whatever one side gained the other lost, as areas were transferred from one designation to the other. That approach neglects the role of a third player, Mother Nature, especially relating to fire, and this means that a joint approach to addressing the risks is desirable.
The ash-type conservation reserves are as much about multiple uses as are state forests. Some uses are common to both, some excluded from one and not the other, and some that vary by degree rather than absolute exclusion in one or the other. We face a future in which there is a material risk that we will lose most or all of these ash-type forests, not over millennia, but in the next 60 y. We can decide to do nothing and accept that loss, or we can engage in active management to conserve their values and uses by reducing the risks across both tenures.