[en] Trends in the Geographic Information System (GIS) have long been difficult to assess comprehensively because of the different perspective of the large number of players in the GIS game. This work represents an overview intended as background to the Workshop Proceedings. As the term GIS means different things to different people the intent is to start with definitions followed by a discussion of data models and inherent functionality of GIS systems. Recent trends are also considered in the context of environmental analyses. Problems arise when considering environmental monitoring due to the paucity of explicit functions dealing with change detection through time. Here parallels are drawn with recent studies which have used the integration of GIS and remotely sensed data. Reasons behind the functional limitations of GIS because apparent as the historical evolution of present day GIS systems is considered, although to some extent these are mitigated by future trends. Finally consideration is given to the role of GIS in assisting with mine site development and especially mine site rehabilitation. 23 refs

[en] A collaborative research agreement between the Supervising Scientist for the Alligator Rivers Region (OSS) and the Northern Territory University (NTU) aims to develop and assess a computer-based Geographic Information System (GIS) to integrate terrain and geological data for risk-hazard analysis and modelling. This paper outlines initial design and development of the prototype GIS including the input of trial data of various types. It is recognised that the GIS must be flexible enough to accommodate change and provide a base for a variety of research needs. Such functionality is likely to be provided best by an initially small, generic prototype GIS to which functions and data are added as required. Properties of the prototype identified as critical to its usefulness include integration of different types of data into the system, understanding and accommodating inconsistencies between data sets and the recognition and recording of error. Various types of data (elevation data, maps and images) available at the outset of the project are outlined together with a brief discussion on their source, integration into the database, derivative products and the potential usefulness of, and problems associated with, the different data formats. The analytical possibilities offered by the trial data will be explored next and the results of the first development cycle presented by the end of 1992. Subsequently, additional data will be incorporated into the database, analytical techniques will be used to build models, and user-driven development will enable the GIS to begin to support a decision research process. 20 refs

[en] This paper outlines one way in which researchers can make a positive methodological contribution to the debate on ecologically sustainable development (ESD) by integrating dynamic modelling and geographical information systems to form the basis for regional scale simulations. Some of the orthodox uses of Geographic Information System (GIS) are described and it is argued that most applications do not incorporate process based causal models. A description of a pilot study into developing a processed base model of ESD in the Northern Territory is given. This dynamic process based simulation model consists of two regions namely the 'Top End' and the 'Central' district. Each region consists of ten sub-sectors and the pattern of land use represents a common sector to both regions. The role of environmental defence expenditure, including environmental rehabilitation of uranium mines, in the model is noted. Similarly, it is hypothesized that the impact of exogenous changes such as the greenhouse effect and global economic fluctuations can have a differential impact on the behaviour of several sectors of the model. Some of the problems associated with calibrating and testing the model are reviewed. Finally, it is suggested that further refinement of this model can be achieved with the pooling of data sets and the development of PC based transputers for more detailed and accurate regional scale simulations. When fully developed it is anticipated that this pilot model can be of service to environmental managers and other groups involved in promoting ESD in the Northern Territory. 54 refs., 6 figs

[en] A Geographic Information System (GIS), embedded in a Decision Support System linking spatial data bases and biophysical models of the environment, will be an important tool in the design and assessment of rehabilitation of uranium mines in the Alligator Rivers Region. The Office of the Supervising Scientist (OSS) and the Northern Territory of University are collaborating in the development of GIS and its introduction into rehabilitation planning. The achievements obtained to date are briefly outlined. There is every expectation that the system developed by OSS will be of general use in environmental assessment and management. 33 refs., 1 fig

[en] The waste products from the mining and milling processes at Ranger include waste rock (containing <0.02%U) and tailings which are contained in a one square kilometer tailings dam. Ranger's preferred strategy for rehabilitation of the minesite involves construction of a 5 square kilometre landform from waste rock and low mineralised material to contain the tailings dam and operational areas of the mine. The objective is to produce a rehabilitated landscape that will release contained elements at a rate and loading that is not significantly different from the natural landforms of the region, which is naturally highly mineralised. Ranger's five-year rehabilitation plan shows the proposed development of below cut-off grade stockpiles in line with the final landform plan and in accordance with planned mining tonnages from the mill and mine five year plans. Progressive revegetation plans, water management aspects of stockpile development and tailings deposition plans are also incorporated into this plan. Some examples of completed research projects are presented. ills