Changing land use in the Canberra region

Abstract

The results of this study of ecological changes in the Canberra region over the past 150 years emphasise the dynamic nature of rural land management, and the need to recognise this in land use planning. It is shown that the arrival of white man in the region in the 1820s introduced a new and dominant impact which previously had no place in the evolution of the landscape. An early dramatic effect was the decline of the aboriginal people who had lived in the region for thousands of years. Through the introduction of disease, direct harassment, and alienation of land used for hunting, the aborigines, as a race, were virtually destroyed in less than a century of white man's occupation of the region. The introduction of exotic grazing and predatory animals, cultivation of the soil and clearing forest and scrub resulted in decimation of native wildlife and marked habitat changes. Simultaneously, the capacity of the land to support European communities was increased, and varied exotic plant and animal species were introduced. With the development of Canberra as Australia's national capital^ land management was oriented to meeting the needs of a city, and agriculture was no longer the most important land use. Land formerly used for crops and grazing stock, was alienated for urban development, softwood timber production, domestic water catchment and recreation. The changes resulting from these activities are described. Increase in population associated with Canberra's growth and changing social patterns created the need for land to be set aside specifically for man's enjoyment and relaxation, and the present use of the countryside for outdoor recreation is examined quantitatively. Results of day use studies and visitor surveys show that recreation use is highly variable throughout the year, the week, and the day, and is strongly influenced by weather conditions, degree of accessibility, and type of facilities provided. Intensive use is concentrated in time and space, and recreation areas may be deserted, or only lightly used, for much of the time. This pattern creates severe problems in the management and allocation of financial and land resources, and indicates the value of multiple land use where places developed for intensive recreation use are located within areas managed for other rural activities such as forestry and agriculture. By contrast there is need for resource-based recreation areas of relatively undisturbed bushland to maintain a diversity of recreation opportunity for present and future human populations. The capacity of local soils and vegetation to withstand impact from recreation is examined. Results of these studies show that changes due to recreational use are highly variable. They may be drastic in the ecological sense but still within acceptable limits for some recreationists, and study to define 'recreational quality' in the perceptual sense is needed. The effect of changing land use on tree distribution patterns is examined in relation to woodland management for aesthetics. Results of seed dissemination studies and examination of tree regeneration patterns indicate methods of assessing land capability to support various types of tree cover. It is shown that many landscapes, now considered attractive, have resulted from man's activities, and continuing management is necessary to maintain them in their present condition. Watersheds are suggested as the bases for land use planning near Canberra to satisfy present demands and maintain flexibility to accommodate future change. Recognition of the importance of an ecological basis to land use planning and management is stressed,if man and his environment are to evolve together in harmony.