To understand the state and trends of Australia’s environment, it is necessary to consider both the historical pressures that have had a profound impact on the environment, and the contemporary pressures that directly and indirectly influence the state of the environment. Historical changes to ecosystems and heritage places set the context for the current state of our environment, and—in many instances—their influences persist. For example, pressure on the environment from land clearing and fragmentation of habitat in Australia includes a legacy of extensive historical clearing. Since European settlement, some 13 per cent of native vegetation has been completely converted for land use, and a further 62 per cent is subject to varying degrees of disturbance.

Many of the contemporary pressures on the Australian environment have increased over time as the drivers of population change and economic activity have increased the demand for food, fibre, minerals, land, transport and energy, and have increased our waste generation.

The main pressures facing the Australian environment in 2016 are the same as those reported in SoE 2011: climate change, land-use change, habitat fragmentation and degradation, and invasive species. Land-use change, habitat fragmentation and invasive species are effects that have been accumulating during the past century or more. In comparison, pressures associated with climate change have only recently had a significant detectable impact.

Although some individual pressures have decreased, such as those associated with air quality, poor agricultural practices, commercial fishing, and oil and gas exploration and production in the marine environment, there is no indication that the major pressures outlined in SoE 2011 have decreased.

SoE 2016 describes a range of other pressures on the Australian environment, including altered fire regimes, overuse of species and habitats, ocean acidification, pollution in our coastal and marine environments, energy production, mining and agriculture. More detail on these pressures is available in the thematic reports.

An image depicting how overlapping, cumulative pressures amplify the threat to the environment. Examples are given for a coral reef and for agricultural land. For instance, extra sediment, climate change and human activities such as fishing and shipping form overlapping, cumulative pressures that can bleach corals and kill fish and reefs while encouraging the spread of invasive species.