Modelling the influences of land use and land management on water quality

This chapter describes the approach taken, the findings and the implications for land managers of research into the influences of land use and land management on water quality in Tasmanian rivers. The objective was to assist future environmental management decisions and investment in water quality protection. Our team approached this task through six activities that spanned four spatial scales (multiple catchment, single catchment, paddock and site) using a combination of historic gauging station data, aerial imagery and modelling. This work resulted in new information on characteristic nutrient generation rates for different land uses, modelled daily nutrient and turbidity concentrations, compared the effectiveness of current cropping practices for managing water and nutrient leaching, assessed the impact of past riparian intervention on water quality and included a simplified conceptual model of the major drivers of nutrient loads and turbidity in Tasmanian catchments. The core of this multi-scale approach, if not all the results, should be of wide relevance to different landscapes across Australia and elsewhere where there are insufficient data and information to be of direct use for managing water quality.