Environmental Engineering Reference
In-Depth Information
5 - Land use and ecosystems
John Williams and Denis Saunders
Two centuries of European-style industrial agriculture has resulted in degradation
of Australia's shallow soils, with increasing salinity, decreased and polluted river
flows, loss of biodiversity and declining trade opportunities. Restoring an ecologi-
cally sustainable environment will require a nation-wide revolution in land use,
involving a mosaic of commercial enterprises in partnership with natural ecosystem
services, including the conservation of Australia's native vegetation and cessation of
land clearing. Tackling the causes rather than the effects of land degradation will
require an integrated approach involving cooperation between agriculturalists, sci-
entists and governments to achieve sustainable food production for Australia and its
trading partners.
Australian agriculture has been very successful for over 200 years, pro-
ducing substantial wealth to support the nation's economic development.
However, we are now producing commodities with ever-declining terms of
trade and at significant cost to the environment. We see the results in exten-
sive losses of species, changes in ecosystem processes, and the increasing deg-
radation of our land and water resources.
The search for farming systems and land use patterns that do not harm
our environment is urgent. In this chapter we will discuss the challenges we
face and pathways towards the solutions.
Australia is a unique, ancient, flat and extremely biodiverse continent
with a dry but highly variable climate. Our geological history has created a
landscape that has accumulated enormous amounts of salts in the land,
lakes, streams and groundwater. Native vegetation has adapted well to these
unusual conditions but unfortunately, most of our European-style agricul-
ture, pastures and annual crops, are ill suited to this landscape, although well
