ACT’s ecological footprint

Background

• Background
• Ecological footprint
• Carbon footprint
• Components of the ACT’s ecological footprint
• ACT’s ecological footprint by expenditure
• Drivers of change

Estimates of the ACT’s ecological footprint have been provided for the four previous ACT State of the Environment reports. An ecological footprint assesses impacts in terms of the Australian land area (in hectares) needed to support a population. This comprises the land for agriculture, forestry, built environments and water required to provide a range of resources, and all goods and services. A footprint also includes a general estimate for the land deemed to be disturbed by the greenhouse gas emissions arising from the population’s resource use and consumption of goods and services. 

Changes in the ecological footprint are an overall measure of the effect our daily activities and resource consumption have on the environment. While the size of the total footprint is influenced by increasing population and changes to industry, individual behaviours can also affect sustainability. Actions to minimise resource use and waste can help to reduce the ACT’s ecological footprint. 

This ecological footprint uses a land disturbance approach. It is based on areas of land use which are weighted by disturbance factors to account for how transformed each land type is from a pristine state. In addition, the calculation of an emissions land component is included. The emissions land component converts the total greenhouse gas emissions to a disturbed land area and is calculated from a full carbon footprint. This methodology has been applied to previous years’ data to provide an assessment of changes to the ACT’s footprint over time.

The ACT’s environmental footprint has been calculated for 2003–04, 2009–10, 2015–16 and 2017–18. For the carbon footprint, the amount of greenhouse gas stored in the ACT’s ecosystems is included in all calculations.

Condition and trends

Ecological footprint

In 2017–18, the total ecological footprint for the ACT was around 2.19 million hectares (Figure HS3). This is over nine times the size of the ACT and means that at current consumption levels, we need an area nine times the size of the ACT to provide the resources, goods and services we use, and to regulate our pollution. It is clear that our current resource use is unsustainable, placing enormous stress on the earth’s natural ecosystems. It is also evident that the ACT’s ecological footprint has consequences for areas of Australia and overseas that provide the wide range of resources, goods and services consumed by the ACT community.

The ACT total footprint peaked in 2009–10 at just under 2.45 million hectares. Since then, the footprint has decreased by nearly 11% despite population growth of over 16% over the same period. This is due to the significant decrease in ACT’s per capita footprint which has fallen by nearly a quarter from 6.9 hectares per person in 2003–04 to 5.24 hectares in 2017–18 (Figure HS4). The decrease means that ACT’s per capita footprint is now equivalent to that for Australia, having been higher for 2003–04, 2009–10 and 2015–16.

Carbon footprint

The total carbon footprint of the ACT population was approximately 5.93 million tonnes carbon dioxide equivalent (CO₂-e) in 2017–18 (Figure HS5). This is a decrease of over 20% from a peak of 7.45 million tonnes CO₂-e in 2009–10. This decrease has occurred despite continued population growth in the ACT over the period, and is a result of a significant decrease in the per capita carbon footprint. The per capita carbon footprint for the ACT fell from 21.5 tonnes CO₂-e in 2003–04 to 14.2 in 2017–18, a reduction of around 34% (Figure HS6). The per capita ACT carbon footprint was 7.5% higher than the per capita Australian footprint in 2003–04, but is now 11% lower than that of Australia.

Components of the ACT’s ecological footprint

Household final consumption is responsible for most (around 70%) of the ACT’s ecological footprint for all years assessed (Figure HS7). This shows the importance of changing community behaviour to minimise resource consumption and waste. Education and awareness-raising on sustainable consumption is imperative to reduce components of both the ecological and carbon footprints for the ACT.

ACT’s ecological footprint is dominated by land disturbance as a result of the large land area required for pasture to produce products such as meat, milk and fibre (Figure HS8). The pasture required to meet the ACT’s demand for such products accounted for around 70% of the per capita footprint for each year assessed. However, the area of land disturbance from pasture requirements has decreased by around 23% from 4.8 hectares per capita in 2003–04, to 3.7 hectares in 2017–18.

The next highest component of the ACT’s footprint was emissions land which was responsible for around 20% of the land disturbance for each year assessed. The per capita area of disturbance from emissions land has also significantly declined in the ACT, from 1.5 hectares per capita in 2003–04 to around one hectare in 2017–18, a decrease of around one-third. The falling contribution from emissions land reflects the ACT’s growing renewable electricity supply.

Other components have a relatively small contribution to the per capita land disturbance footprint and show little change over time. These include disturbances from dry cropland (around 4% of the per capita footprint for all assessed years), forestry (around 2%) and the built environment (around 1%). Results for the built environment again reflects just how little of the ACT’s per capita ecological footprint is contained within the ACT.

ACT’s ecological footprint by expenditure

Ecological footprint calculations can also be considered by consumption category. This can help guide community action and government policy aimed at reducing the ACT’s footprint. The consumption categories are food, shelter, energy use, mobility, goods, services and other. All flow-on impacts are included within each category. For example, the land required to grow wheat and the energy used to harvest the wheat is all included within the food category. The services category covers a large number of services, including telecommunications, finance, medicine, entertainment and government. 

The provision of food dominates most ecological footprints due to the extensive land required for the average diet. Food expenditure accounted for around 50% of the ACT’s total footprint for all years assessed with no evident trend (Figure HS9). Selecting more locally-produced and alternative sources of protein with lower footprints could substantially reduce the overall footprint of the ACT.

Services was the next highest contributor to the footprint at around 20% for all years assessed, again with no clear trend.

Goods decreased from 269,000 hectares (11% of the total footprint) in 2009–10, to around 186,000 hectares (8% of the total footprint) in 2017–18. The contribution from goods is falling as expenditure patterns shift further towards services. 

Energy use has also decreased from 6% to 4% of the total footprint reflecting the growth in renewable energy.

For carbon footprints, the expenditure groups have a much more even contribution with services, mobility and food all making substantial contributions to the ACT’s carbon footprint.

There has been a notable decrease in the carbon footprint from energy due to the increase of renewable electricity in the ACT. The energy footprint fell from around 1.75 million tonnes CO₂-e (23% of the total carbon footprint) in 2009–10, to around 900,000 tonnes CO₂-e (15%) in 2017–18 (Figure HS10).

In 2017–18, mobility was responsible for 25% of the total carbon footprint, rising from 19% in 2002–03. However, in terms of total tonnes CO₂-e there has been little change in mobility since 2009–10 with the change in percentage contribution mainly due a decreasing energy footprint.

Other changes in the carbon footprint include a 168,000 tonnes CO₂-e (10%) decrease from services between 2009–10 and 2017–18, and a 120,000 tonnes CO₂-e (14%) decrease from goods over the same period.

Drivers of change

The main drivers for changes in the ACT ecological footprint include: 

• a very slow rate of increase in household final consumption since 2008 
• a decrease in median household income leading to a plateauing of expenditure increases 
• a decline in expenditure on components with higher footprint intensities 
• increases in housing costs contributing to reduced expenditure 
• increases in the services component of ACT household expenditure (health and education in particular) 
• relatively small increases in household greenhouse gas emissions 
• increase in renewable electricity reducing the energy footprint 
• household consumption contributes most to the ACT’s total footprint 
• private car emissions are now one of the ACT’s biggest carbon footprint components and are likely to increase with the growth in private vehicle use and commuting times, and 
• air travel was only responsible for around 3.5% of the total 2017–18 carbon footprint, but is growing.