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The sustainability of agricultural practices is enhanced when vegetation makes optimal use of natural hydrological processes. For example, planting tree belts where slope gradient sharply decreases can enable harvesting of run-on water. This can be beneficial for example in reducing water logging and enhancing tree production. There is a need for rapid and low cost identification of water flow paths and conceptualisation of hillslope hydrology so that local landuse planning can reflect such opportunities. The collection of detailed hillslope hydrological data is prohibitively expensive for such applications and so the use of soil morphology and visual observation of topography and surface condition is evaluated as an alternative. At a study site in south eastern Australia the soil physical profile was described down a hillslope with additional measurements of the hydraulic conductivity, bulk density, cation exchange capacity, electrical conductivity, and particle size distribution of the key horizons. This data was used to identify the perceived significant hydrological flow paths down the hillslope. Measurement of the surface runoff, subsurface lateral flow, and the distribution of saturation measured in piezometers were subsequently used to test the conceptual hydrological model. Soil morphology, particularly the soil colour and presence of redox concretions were useful in identifying the locations and depths where saturation and lateral flow occur. The morphology provides an integrated reflection of the dominant hydrological conditions, but care must be taken to ensure that the observations reflect the current hydrological environment and not relic conditions. Other collaborating information such as the history of geomorphological events at the site, a validation of plausible water sources for the potentially transmitting layers, surface soil condition and landholder observations give improved confidence. Combining soil morphological understanding with visual obs

This report recommends a range of protocols and actions required by a number of agencies that will ensure the successful long-term monitoring of soil condition across Australia. The four priority processes which potentially have a major impact on the welfare of the Australian population are wind erosion, water erosion, soil acidification, and soil organic carbon change. These processes are difficult to monitor because they usually affect large areas and are either irregular or progress very slowly. The monitoring protocols released in 2003 did not adequately address these difficulties. The Expert Panels identified a range of factors which require attention. • The current institutional framework within Australia is unsuited to long-term monitoring and a long-term mandate is required. • The biggest advances in monitoring soil condition are likely to come from improved data for modeling. • There are dual objectives for monitoring: local monitoring for project management and accountability, and broader monitoring for the purpose of managing the national soil resource base. These two objectives often demand different approaches. Recommendations specific to each of the four processes appear in the appropriate chapters.