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Land application of wastes is becoming an increasingly popular practice. The application of farm dairy effluent (FDE) to land, as opposed to direct discharge to waterways, is the preferred mechanism for disposal in New Zealand as regulatory authorities move to protect and enhance water quality and meet Maori spiritual and cultural values. For example, in the Waikato the percentage of dairy farmers who apply FDE to land has risen from 35% in 1993 to effectively 100% in 2004. Land application recognises the nutrient value of FDE; however, it is not without risks. At present the management of land application of FDE is primarily concerned with potential nitrate contamination of groundwater. There are other, considerable, potential risks such as microbial contamination and impacts on soil properties. Despite soil properties being spatially extremely variable and the effects of land application of FDE being long-term, the majority of studies on the impacts of FDE to soil properties are limited in their temporal and spatial extent. The evidence of effects of FDE on soil properties is limited; however, it is reviewed and linked to the effects of land application of other effluents in general and their effect on specific soil properties. The effects of FDE application on soil physical properties are highly variable (e.g., both increases and decreases in soil hydraulic conductivity have been observed). This is in part because of measurement issues and the difficulty in separating out the effects of the FDE application from the effects of stock management. Overall, most changes due to FDE application appear to improve the soil's long-term fertility, i.e., increased concentrations of total nitrogen, total phosphorus, and plant available nutrients. FDE application has been observed to result in a greater and more diverse microbial biomass. However, optimal environmental management and the continued use of the soil for FDE management require ongoing monitoring. [ABSTRACT FROM AUTHOR]

The article discusses the challenges faced by public administration issues in the country following the leadership of Sir Robert Garran, former public officer of the Commonwealth of Australia. It claims that post-Garran public administration faces several pressures on how to achieve the same satisfaction from the public. Economically, it notes that the country also encounters demands on how to make the people's future more prosperous. Moreover, it urges the government to ensure the efficiency of public service for the betterment of public management and decision making in the country.

A foreword to the special issue of the "Australian Journal of Political Science" is presented.

Rill development studies have focused almost exclusively on surface erosion processes and critical threshold hydraulic conditions. Characteristic rill features, such as arcuate headcuts and knickpoints, aremorphologically similar to the theatre-headed valleys which have been associated with sapping processes at various scales. This paper reports on laboratory experiments designed to identify linkages between surface flow hydraulics, subsurface moisture conditions and rill development. Experiments were carried out in a 16.57 m2 flume under simulated rainfall with soil samples up to 0.15 m depth in which moisture conditions were monitored by miniature time-domain reflectometer probes. Tests showed complex responses in which some rill incision reflected surface flow conditions, but major rill system development with markedly enhanced sediment yield was closely associated with high soil moisture contents. It was not possible to measure seepageforces directly, but calculation and observation indicate that thesewere less important than reduction in soil strength with saturation,which resulted in increased effective runoff erosivity. This caused concentrated undercutting along the water table at rill walls, while slightly stronger surface layers above the water table formed microscarps. These retreated along the water table into interrill surfaces, producing residual pediment transport slopes. The microscarps eventually disappeared when the water table reached the surface, eliminatingdifferential soil strength. The experiments showed complex relationships between surface and subsurface erosional processes in evolving rill systems, strongly influenced by soil moisture dynamics. The very small topographic and hydraulic head amplitudes indicate that seepageforces and sapping were minimal. The dominant effect of soil moisture was reduction of soil strength with saturation, and increased runoff entrainment. Experimental conditions were not unusual, either for agricul [ABSTRACT FROM AUTHOR]