Savanna fire management and bushfire and natural hazard scenario planning for north Australia

Savanna fire management and bushfire and natural hazard scenario planning for north Australia

.This project has three major components: - Savanna burning - Management of high biomass weeds - Spinifex and mulga landscapes. Savanna Burning: The Savanna Burning project builds on the substantial work previously undertaken within the Bushfire CRC’s North Australian Fire Mapping project. The project developed a comprehensive algorithm for mapping fire effects on tropical savanna vegetation. These data and the annual fire history mapping data were then applied in preliminary analyses to assess the risk to biodiversity, greenhouse gas emissions and ecosystem services in general under various climate scenarios. The Savanna Burning project will build on this work by gathering finer scaled data and undertaking more detailed assessments of these and other criteria in regions defined as being at greatest risk. The preliminary analyses suggested that the most deleterious effects to ecosystem services occur predominantly on indigenous owned and/or managed lands. Therefore, the project will involve consultation with lead indigenous groups such as the North Australia Indigenous Land and Sea Management Alliance and the Land Councils to determine those areas where it would be most feasible to undertake the detailed analyses through the collation of fine scale spatial data leading to research determining community resilience to those risks. This project will expand upon broad-scale bushfire risk assessments in previously determined high risk regions using higher resolution spatial analyses. Current risk assessments include impacts on greenhouse gas emissions abatement, biosequestration, soil erosion, biodiversity, communities, and enterprises—under different management and climate scenarios. Managing flammable high biomass grassy weeds: A range of invasive grasses have spread rapidly in tropical Australia over the past two decades, substantially altering the savanna, riparian and wetland ecosystems. These grasses include: • Gamba grass (Andropogon gayanus) • Mission grass (Pennisetum polystachion) • Annual mission grass (Pennisetum pedicellatum) • Grader grass (Themeda quadrivalvis) • Para grass (Urochloa mutica) • Olive hymenachne (Hymenachne amplexicaulis), and • Alemann grass (Echinochloa polystachya) The ecological, economic and social consequences of these grasses are so significant that many are now declared at the Territory and State level, have been listed as Weeds of National Significance, and listed as a Key Threatening Process under the EPBC Act. The impacts are primarily due to the substantial change in fire regime, with more frequent fires occurring at intensities higher than ever recorded previously in north Australian tropical ecosystems. In the NT, special fire zones have already been declared based on the increased fuel loads and fire risk resulting from high-biomass grasses. There is a lack of decision support tools or models to effectively inform the longer-term consequences of grass invasion or the optimal decisions regarding the allocation of resources to manage this fire risk. The lack of these tools directly affects determinations about where to invest scarce resources to have the greatest impact on reducing risk and improving community resilience. This project will assess the likelihood and magnitude of risk of high biomass invasive grasses to fire regimes in the tropical savanna region and provide critical information for Government policy and planning, particularly prioritisation of weed risk for fire-regime changing species, and for fire management planning Central Australian spinifex and mulga landscapes: Substantial R&D has been undertaken over the past 15 years into the development of savanna burning greenhouse gas emissions abatement and sequestration methodologies, and associated project applications. There may also be considerable potential for the development of complementary methodologies focusing on improved fire management of extensive central Australian mulga- and spinifex-dominated rangelands. Most prospective is a biosequestration methodology focusing both on mulga (Acacia aneura) and spinifex (Triodia spp). Unlike tussock grasses, Triodia continues to accumulate biomass at decadal scales similar to woody shrubs. Available national mapping sources indicate that such landscapes cover at least a quarter of the continental landmass. These landscapes are very sparsely settled (mostly by Aboriginal people in small isolated communities), and support no economically significant agricultural or pastoral enterprises. Despite the extreme aridity (with highly annually variable mean annual rainfall conditions <250 mm / yr) of mulga-spinifex landscapes, very extensive fires occur in the contemporary era particularly after intermittent rainfall events. These contemporary ‘boom and bust’ patterns contrast strongly with the well-documented patchwork fire mosaics maintained under Aboriginal fire management until as recently as the late 1950s in some regions. This project will contribute to the development of an approved Carbon Faring Initiative (or related) biosequestration methodology addressing improved fire management under central Australian conditions. In the longer term, to provide an economic and employment foundation for remote central Australian communities to develop land management enterprises / undertakings so as to provide a sustainable basis for developing stronger and more resilient communities.