Agricultural landscapes in Australia have historically been places of ecological decline. Habitat loss and fragmentation from land clearing, overgrazing by livestock and feral herbivores, inappropriate fire regimes and weed invasion in remnant vegetation are among the factors that pose challenges for conservation in these landscapes. Yet agricultural landscapes retain important conservation values, and new incentives for nature-positive outcomes will provide opportunities for changes in farm management that improve biodiversity outcomes.
The vulnerable red-lored whistler (Pachycephala rufogularis) is a mallee specialist. Photo JJ Harrison CC BY-SA 3.0.
This project is developing state-and-transition models, interactive maps and practical decision-support tools to help land managers understand how ecosystems change and identify actions that can maintain or improve their condition.
The research brings together two complementary areas:
investigating how changes to grazing and fertiliser management can improve biodiversity in working agricultural landscapes without compromising farm production or profitability
safeguarding Mallee birds and their habitats in the Murray Darling Depression.
Limestone Coast state-and-transition models
State-and-transition models of the agricultural zone: flooding red gum woodland, lowland resprouting woodland and sedgelands.
State-and-transition models describe the different condition states in which an ecosystem can occur and the processes that move it from one condition state to another.
For example, an ecosystem may transition from a relatively intact state to a modified or highly modified state because of grazing, clearing, weeds, changed fire regimes or altered hydrology. Management actions such as controlling grazing, restoring vegetation, managing fire or improving hydrological conditions may support recovery.
By bringing this information together, the models can help land managers:
recognise ecosystem condition
understand the pressures driving change
identify possible degradation and recovery pathways
compare management options
plan monitoring, restoration and conservation activities.
The project has developed state-and-transition models for three ecological systems in the Limestone Coast agricultural zone of south-eastern South Australia:
flooding red gum woodland
lowland resprouting woodland
sedgelands.
These ecosystems occur within a productive agricultural and forestry region but have been affected by vegetation clearing, wetland drainage, altered hydrology, grazing, nutrient enrichment and weeds. Remaining woodlands and wetlands provide important habitat, ecological connections and hydrological and cultural values.
The models describe condition states ranging from reference condition to modified, highly modified and collapsed or transformed states.
They identify degradation pressures such as:
clearing and continuous grazing
altered fire regimes
drainage and loss of seasonal waterlogging
nutrient enrichment
weed invasion
drought and climate pressures
conversion to agricultural land.
Potential recovery actions include strategic grazing, revegetation, ecological burning, weed control, reducing nutrient inputs, restoring wetland hydrology, fencing paddock trees and supporting natural regeneration.
The models are designed as practical decision-support tools that connect regional ecological knowledge with condition assessment, spatial mapping and management planning.
The Murray Darling Depression supports a nationally important ecological community of threatened and declining Mallee birds.
The project has developed a regional state-and-transition model for Mallee ecosystems across South Australia, Victoria and New South Wales. The model covers three broad vegetation types:
Chenopod or Tussock Grass Mallee
Shrubby or Triodia Mallee
Mesic Heathy Mallee.
The model describes ecosystem conditions ranging from relatively intact vegetation to modified and collapsed or novel states. It also identifies how pressures such as grazing by stock and/or feral herbivores, altered fire regimes, clearing, soil disturbance and climate change can affect habitat condition.
Potential recovery pathways include controlling feral herbivores, decommissioning dams and artificial waterpoints, strategically managing fire and restoring native vegetation. The model provides a foundation for monitoring, restoration planning and testing how Mallee ecosystems may respond to different management scenarios.
The project also rates the habitat value of each ecosystem condition state for each of the bird species in the threatened Mallee bird community.
Improving biodiversity in working agricultural landscapes
The project is investigating how changes to fertiliser and grazing management may help agricultural ecosystems transition to higher biodiversity condition states.
Research is taking place across approximately 10–12 farms in each of three regions:
Tasmanian Midlands
Western Victorian Volcanic Plains
Limestone Coast.
The research compares paddocks with different histories of fertiliser use and grazing management. It measures ecosystem condition and biodiversity indicators, including plants, selected invertebrate groups, bats, birds and soils.
The findings will be used to update and validate regionally specific state-and-transition models and develop:
a monitoring framework for assessing ecosystem condition in production areas
practical advice for landholders seeking to improve biodiversity and landscape resilience
stronger evidence for sustainability reporting, natural-capital accounting and emerging nature markets.
How the research supports conservation action
The project’s models, reports and interactive maps will help land managers and decision-makers understand how management affects biodiversity and ecosystem condition.
The research can support:
Mallee bird habitat management
grazing, fire and vegetation management planning
restoration planning
biodiversity and natural-capital monitoring on farms
assessment of changes to farming practices
biodiversity incentives, nature markets and sustainability reporting.
By linking management actions with ecological outcomes, the project will support better conservation and sustainable agriculture decisions.
Endangered Mallee emu-wren (Stipiturus mallee). David Cook CC-BY-NC 2.0
Murraylands and Riverland Landscape Board, Landscape Ecology
River Murray and Mallee Aboriginal Corporation (RMMAC)
Australian Landscape Trust, Calperum and Taylorville Stations
Birdlife Australia, Gluepot Reserve
SA Department of Environment and Water, Riverland and Murraylands National Parks Science Group
Department of Primary Industries and Regions (SA), Climate Change Team
Tree for Life (SA), Vegetation Services
Parks Victoria; Environment, Land and Water, Northern Victoria
Victorian Department of Energy, Environment and Climate Action: Natural Environment Programs, Loddon Mallee Region; State Forests, Loddon Mallee Region
NSW Department of Planning and Environment, Biodiversity Conservation Division
DCEEW, Biodiversity Division: Office of the Threatened Species Commissioner; Protected Species and Ecological Communities Branch