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For benthic marine invertebrates with planktonic larvae, adult abundance at the species' range limit may depend on local fecundity, and recruitment from central, source populations. We tested the importance of these processes using a hierarchical design at multiple spatial scales (from tens to hundreds of kilometres) to assess relationships between patterns of adult abundance, fecundity and recruitment in the rocky intertidal barnacle Tesseropora rosea, approaching its geographical range limit on the southeast coast of Australia. Across the 600 km region, adult abundance, recruitment and fecundity all declined towards the range limit, but only adult abundance and recruitment were positively correlated, suggesting that recruitment is negatively affected at the range limit and that recruitment plays a significant role in setting the geographical patterns of abundance of T. rosea. In contrast, at smaller spatial scales within this region, adult abundance and recruitment varied by up to 15- and 100-fold, respectively, among some locations only tens of kilometres apart, and no obvious patterns in adult-recruit relationships were revealed towards the range limit. Local patterns of abundance and life-cycle relationships do not, therefore, translate to biogeographic scales, but investigation at this multitude of spatial scales helps to identify the defining processes that account for spatial variation and determine population structure towards the range limits of benthic marine invertebrates.

The school environment has an essential role in encouraging children to exercise. This study explores variables which may contribute to increased activity levels on the playground.

Soil erosion in the Canterbury high country has been a concern for many years, and Environment Canterbury wishes to encourage land management practices that will preserve soil quality and vegetative cover. Environment Canterbury brought to MISG2005 a data set spanning three decades of bare ground monitoring in the Canterbury high country, along with data on factors with potential to impact on the processes of revegetation. These include topographic and climate data, soil nutrient status and land management factors. The study group analysed these data with the aim of determining whether trends in bare ground can be predicted from the potential causative factors. Analysis was difficult due to the high level of confounding between many of the variables, such as soil quality with land management. However a predictive model of change in percent bare ground was derived (explaining 63% of the variation in the data) in which the most important factors were fertiliser application, percent bare ground at the start of the monitoring period, annual average temperature and winter rainfall. Removal of low intensity grazing (to no grazing) had no discernable effect on percent bare ground.

Objective: Investigation of relative bias in diet history measurement during dietary intervention trials. Design: Retrospective analysis of human dietary data from two randomised controlled trials examining modified fat diets in the prevention and treatment of type II diabetes mellitus. Setting: Wollongong, Australia. Subjects: Thirty-five overweight, otherwise healthy subjects in trial 1 and 56 subjects with diabetes in trial 2. Interventions: Diet history interviews and three-day weighed food records administered at one-month intervals in trial 1 and three-month intervals in trial 2. Results: In a cross-sectional bias analysis, graphs of the association between bias and mean dietary intake showed that bias decreased in higher carbohydrate consumers in trial 1 ( r = −0.344, P<0.05 ). No other significant associations were found. In a longitudinal analysis, bias did not change over time in either trial. There were no significant differences in bias magnitudes between the trials, with the exception of monounsaturated fat measurement where bias was significantly greater and more positive in trial 2, indicating overestimation of monounsaturated fat intake with the diet history. Subjects in control and intervention groups underestimated energy, fat, saturated fat and alcohol intakes with the diet history in both trials. Overweight and obese individuals appeared to make the greatest contribution to the overall underestimation of saturated fat intake by the diet history regardless of whether they were in the control or intervention group and whether they were healthy or had diabetes. Conclusion: Bias in diet history measurement appears to be macronutrient-specific, with energy, fat and saturated fat consistently underreported in the interview by subjects with and without diabetes and in both intervention and control groups in a dietary intervention trial. Relative bias analysis appears to be an informative tool in quality control for dietary intervention trials when bioch