Interdependence in the environment

Interdependence in the environment

Within an ecosystem there are interdependent relationships between the species of that environment which are recognised and understood in Aboriginal and Torres Strait Islander ecological knowledge and practices.

Fire and interrelationships among matter and species in ecosystems

Fire is an example of an abiotic (non-living) factor that affects the flow of matter within an ecosystem, and the inter-relationships of the organisms within that ecosystem. Within an ecosystem there are interdependent relationships between the species of that environment. For example, herbivorous animals are dependent on plant life for food, many animals are dependent on plants for protective cover or nesting, and both plant and animal life are dependent on abiotic factors such as water, nutrients, light and suitable temperatures. Changes to these factors affect the interrelationships within the ecosystem.

Fire is an abiotic factor that affects such interrelationships, and how fire is applied to an ecosystem affects the nature of those relationships. Uncontrolled bushfires expose ecosystems to prolonged high intensity burns, destroying organisms and habitats, often irretrievably1. However, fire does not need to be a detrimental factor to an ecosystem.

Aboriginal peoples and Torres Strait Islander use of fire as a land management tool is well documented. The application of fire can be used to manage paths for travel, clear area around residential sites for strategic purposes and control the availability of resources through selective application of fire to each distinct ecosystem2. This is commonly referred to as ‘fire-stick farming, and refers to the sensitive and systematic application of fire by Aboriginal and Torres strait Islander people to manage the environment3. It is considered by many as a distinct agricultural practice.

For tens of thousands of years, knowledgeable Aboriginal and Torres Strait Islander people have recognised the effect of fire on interdependent communities of organisms. The application of this knowledge allows people across the continent to facilitate growth and distribution of plant species, and promote the growth of suitable environments for fauna.

Aboriginal and Torres Strait Islander knowledge systems are orally transmitted and knowledgeable people have a deep understanding of the environment of their country and know that certain native species have, over very long periods, adapted to fire regimes. The careful and methodical facilitation of fire treatment of those environments acts to maintain ecosystems, promote the growth of fire dependent species and encourage environmental biodiversity.

The low intensity application of fire, often called cool burning, returns nutrients to the soil through ash, promotes germination of fire dependent species and encourages the growth of suitable habitats for the animals in that ecosystem4. The Wathaurong people of the Kulin Nation in south central Victoria are reported to have prepared the ground for fertilization by aerating the soil prior to fire stick farming, allowing the ash to permeate the soil, promoting the ideal conditions for the growth of highly nutritious food sources such as yams5. The use of low intensity fire also clears country to prevent build up of fuel load that may facilitate a destructive higher intensity fire and can provide a protective clearing for environments, such as rainforest, that is fire-sensitive6.

Traditional land management practices were disrupted following the arrival of Europeans in Australia, who failed to understand the significance of such practices. The consequences of this were quickly apparent with loss of biodiversity within ecosystems including the endangerment of species, unchecked invasion of introduced species, such as gamba grass, and increases in the number of large-scale destructive bushfires. Traditional land management practices are now understood to significantly decrease greenhouse gas emissions compared to an uncontrolled bushfire7.

Across the continent, various fire abatement schemes exist to reduce greenhouse gas emissions and protect property. These schemes have generated a positive effect on the biodiversity outcomes within implementation areas. Indigenous rangers in south east Arnhem Land in the Northern Territory are applying Aboriginal ecological knowledge to manage country as part of the South East Arnhem Land Fire Abatement Project (SEALFA )8. The rangers who operate this project are reducing carbon emissions by preventing bushfires, conserving rainforest vegetation and protecting local wildlife. In the Torres Strait Islands, the Land and Sea Management Strategy has developed unique fire management plans for 7 of the Islands based on traditional knowledges, as fire management requirements vary significantly for each ecosystem9.


Classroom activity - Science Year 9

This classroom activity provides students with the opportunity to develop science understanding of the interdependencies of ecosystems, abiotic factors and matter and energy flow through the context of Aboriginal and Torres Strait Islander use of fire to manage country.

Students will construct an interdependency diagram to model the interactions of plants, animal and other biotic factors in their local ecosystem. Students will research the land management practices of different landscapes and make a recommendation for the most appropriate land management practice suitable for their local region, justifying their decision. Students can then construct a second inter-dependency model to demonstrate the impact they hypothesise this management strategy would have on the ecosystem.

Curriculum connections

This resource addresses the following content descriptions from the Australian Curriculum:

  • Scientific understanding, including models and theories, is contestable and is refined over time through a process of review by the scientific community (ACSHE157)
  • People use scientific knowledge to evaluate whether they accept claims, explanations or predictions, and advances in science can affect people’s lives, including generating new career opportunities (ACSHE160)
  • Ecosystems consist of communities of interdependent organisms and abiotic components of the environment; matter and energy flow through these systems (ACSSU176)

This resource addresses the following excerpts from the achievement standard for Year 9 in Science:

  • analyse how biological systems function and respond to external changes with reference to interdependencies, energy transfers and flows of matter
  • describe social and technological factors that have influenced scientific developments and predict how future applications of science and technology may affect people’s lives
  • evaluate others’ methods and explanations from a scientific perspective and use appropriate language and representations when communicating their findings and ideas to specific audiences

Activity - Understanding local fire management plans

1. Students can investigate the species present in their local ecosystem using the “Explore your area” tool through the Atlas of Living Australia10 or through field studies. Students can list the dominant organisms present in their local ecosystem and construct an interdependency diagram to demonstrate the interrelationships between these organisms. An example of interdependency maps can be seen in ‘How Fires Affect Biodiversity’11

Students should discuss the following inquiry-based questions in small groups:

  • Which species in your interdependency diagram were you already familiar with? Have you encountered them your the local ecosystem?
  • Which interrelationship between two species most surprised you? Why? Consider the effects if one of these species was to become extinct.

2. Students should investigate the fire management practices that are advised for their specific ecosystem to inform a recommendation for their local area. Teachers should be aware that Aboriginal and Torres Strait Islander peoples knowledges of fire management practices are intrinsically linked to the local environment. Local Aboriginal or Torres Strait Islander Land Council organisations could be contacted to identify the current fire management practices recommended for the local area. Where this is not possible, the table below provides a range of available information for more detailed fire management strategies. Students can compare and contrast the different landscape types with their own ecosystem to identify a landscape that is most comparable to their local ecosystem. Students can use the fire management practice information from their local area to inform a recommendation for the most appropriate fire management strategy and justify their rationale.

3. Students can then evaluate the impact the fire management recommendation will have on the ecosystem through a second inter-dependency model, predicting the changes to the ecosystem with the implementation of the fire management recommendation.

Fire Management Guidelines

The table below provides information of available fire management guidelines organised by state, territory or region. The guidelines can be used to find more specific fire management information to landscapes across Australia. Where relevant, the page has been provided for relevant information.

State/Territory/Region

Link 

Page

NSW

Guidelines for ecologically sustainable fire management (NSW Biodiversity Strategy)

Page 34

QLD

Benchmarks (Queensland Government)

Fire management guidelines – excel spreadsheet (Queensland Government)

Use spreadsheet with benchmark areas

SA

Ecological Fire Management Guidelines (Government of South Australia)

Page 28

TAS

Fire management (Tasmanian Government)

Page 6

Tropical Savannah 

Gulf Savannah Fire Management Guidelines (Carpentaria Land Council Aboriginal Corporation)

Biome Specific

VIC

Fire ecology (Country Fire Authority)

Page 29

WA

Guiding principles for fire management in the Western Australian rangelands (Rangelands NRM)

Region specific

Notes

1 CSIRO. (2009). Bushfires in Australia. Retrieved from https://www.aph.gov.au/DocumentStore.ashx?id=3d4e5dd5-9374-48e9-b3f4-4e6e96da27f5

2 Petty, A. (2012). Introduction to Fire-Stick Farming. Fire Ecology, 8(3), 1–2.

3 Jones, R. (2012). Fire-Stick Farming. Fire Ecology. 8(3), 3-8.

4 R. Bliege Bird, D. W. Bird, B. F. Codding, C. H. Parker, & J. H. Jones. (2008). The “fire stick farming” hypothesis: Australian Aboriginal foraging strategies, biodiversity, and anthropogenic fire mosaics. Proceedings of the National Academy of Sciences, 105(39), 14796–14801. https://doi.org/10.1073/pnas.0804757105

5 Djillong. Land cultivation. Retrieved from http://www.djillong.net.au/traditions/land-cultivation.html

6 McCaw, W.l. (2013). Managing forest fuels using prescribed fire - A perspective from southern Australia. Forest Ecology and Management, 294, 217–224. https://doi.org/10.1016/j.foreco.2012.09.012

7 CSIRO. (2018). Burning to manage greenhouse gas emissions. Retrieved from https://www.csiro.au/en/Research/LWF/Areas/Ecosystems-biodiversity/Managing-landscapes-for-biodiversity/Fire-ecology/Burning-emissions

8 Northern Land Council. (2017). South east Arnhem Land fire abatement (SEALFA) project. Retrieved from https://www.nlc.org.au/media-publications/south-east-arnhem-land-fire-abatement-sealfa-project

9 Torres Strait Regional Authority. (2016). Land and sea management strategy for Torres Strait 2016-2036. Land and Sea Management Unit, Torres Strait Regional Authority.

10 https://www.ala.org.au/explore-by-location

11 Gill (1996): https://www.anbg.gov.au/fire_ecology/fire-and-biodiversity.html#INF

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The development of these resources was funded through an Australian Government initiative delivered by the University of Melbourne's Indigenous Studies Unit. The resources include the views, opinions and representations of third parties, and do not represent the views of the Australian Government. They have been developed as a proof of concept to progress the inclusion of Aboriginal and Torres Strait Islander content in Australian classrooms. In drawing on the material, users should consider the relevance and suitability to their particular circumstances and purposes.