Editors: Kerry

6.2 Environmental impact

The impact of population growth on the nation’s natural capital is a huge issue which has attracted sustained informed, uninformed and passionate debate. Main areas of concern with respect to increased population levels include pressures that are placed on natural resources and the environment through land degradation, depletion of resources and threats to ecosystems. Some argue that effective environmental policies which might not only repair past environmental damage but also inhibit future degradation are unlikely to be implemented without a smaller population base (Flannery 1995). Therefore, from this perspective, an increase in population as a result of immigration should be discouraged. Limiting immigration, and thus population growth, also reduces the imperative to act with respect to waste production and excessive lifestyles and so, some argue, presents a ‘lazy’ way to tackle environmental problems (Burnley 2003b).

Another perspective is that national population growth, even with a modestly raised immigration intake, is an extraneous factor with respect to environmental problems. Existing pressures in and around cities and in rural primary production areas demand that environmental and resource management strategies be put firmly in place and consumption and resource use practices be significantly modified (Burnley 2003b). Burnley argues that, provided these occur, increases in population to, say, 26 million by 2050, as projected by the ABS (2000a), would not place unacceptable stresses on the physical environment.

Furthermore, if Australia were to reduce population growth via immigration as a result of agendas determined by environmentalism and nationalist sentiments, the nation could become marginalised in a global sense (Burnley

2003b). This view receives support in a Federal Government report into Australia’s carrying capacity which suggested that a smaller population would not reduce land use by agricultural and pastoral industries and thus not impact upon associated environmental degradation (House of Representatives Standing Committee for Long Term Strategies 1994). Other major studies have likewise shown that land degradation is not causally linked to national population growth (Castles et al. 1998; Wooden et al. 1994).

Effect on levels of natural resources

A further area of concern with population growth is depletion of natural resources such as water and non-renewable minerals. Given international

trade and factor substitution possibilities, population growth might be expected to have little impact on depletion rates of most non-renewable resources (Cocks 1996). However, ‘common property’ resources, such as fisheries and forests and, of course, water, might need careful management to avoid exploitation at unsustainable levels (Castles et al. 1998).

Implications for habitat modification

The potential for increased population levels to endanger ecosystems is an issue because population growth has a clear impact on habitat modification. In addition, lower population levels might marginally reduce efforts required for Australia to meet international commitments on greenhouse emissions. As against this, humans have biodiversity consequences irrespective of where they live so that the net impact from a global as opposed to simply an Australian perspective is far from clear. As a result, migration reduction is probably an inappropriate vehicle for protecting ecosystems if a global perspective is adopted (Castles et al. 1998).

Where immigrants live is critical in terms of their impact on natural capital. Approximately 36 per cent of current migrants settle in Sydney, potentially adding to the air and water pollution problems that derive from that city’s location in the Sydney basin. This influx of migrants needs to be set in the context of Sydney’s pattern of internal migration because many immigrants have settled in established areas that have been vacated selectively by Australia-born or other immigrants as they move to satisfy housing aspirations appropriate to stage of life cycle (Burnley et al. 1997).

Internal mobility within Australia as a whole has also meant that population growth might have shifted to locations such as Brisbane or Perth (Castles et al. 1998). Thus settlement patterns of immigrants might counter rather than aggravate internal population flows (S. Richardson 2002).