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New Zealand is highly dependent on its soil resource for continued agricultural production. To avoiddepleting this resource, there is a need to identify soils and associated land management practices wherethere is a risk of soil degradation. Environmental integrity and ecosystem services also need to be maintained.Accordingly, to ensure sustainable production, the on- and off-site environmental impacts of land managementneed to be identified and managed. We developed a structural vulnerability index for New Zealand soils. Thisindex ranks soils according to their inherent susceptibility to physical degradation when used for agricultural(pasture, forestry and cropping) purposes. We also developed a rule-based model to assess soil compactionvulnerability by characterising the combined effects of resistance and resilience. Other soil attributes havebeen appraised using seven chemical, physical and biological indicators of soil quality. These indicators havebeen applied in a nation-wide project involving data collection from over 500 sites for a range of land uses.These soil quality data can be interpreted via the World Wide Web - through the interactive decision-support tool SINDI. The land-use impact model is a framework to assess agricultural land management andenvironmental sustainability, and may be applied to land units at any scale. Using land resource data andinformation the model explicitly identifies hazards to land productivity and environmental integrity. It utilisesqualitative expert and local knowledge and quantitative model-based evaluations to assess the potentialenvironmental impacts of land-management practices. The model is linked to a geographic informationsystem (GIS), allowing model outputs, such as the environmental impacts of site-specific best managementpractices, to be identified in a spatially explicit manner. The model has been tested in New Zealand in anarea of pastoral land use. Advantages of this risk identification model include: utilising current knowledge ofthe causes and effects of land-management practices on soil degradation; linking land management practiceto both on- and off-site environmental consequences; identifying important gaps in local knowledge; andproviding spatially explicit information on the environmental impact of land-management practices.