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Context The goal of increasing sequestration of carbon (C) in soil assumes that management factors can be as influential as intrinsic factors such as climate and parent material. Aim The hypotheses tested in this study were (i) that soil C would increase more in limed than in unlimed pasture treatments, and (ii) that well-managed perennial pasture treatments would accumulate soil C to a greater depth than annual pasture treatments. Method An 18-year field experiment was conducted on a duplex soil in the mixed farming zone of south-eastern Australia. The experiment contained four treatment contrasts: limed and unlimed perennial and annual pasture systems. Soils samples to 120cm were taken annually and analysed for C and nitrogen (N) concentrations. Soil C and N stocks were calculated. Key results The four treatments produced a similar annual rate of increase in soil C concentration and C stocks. The increase in C stock was confined to the surface 30cm of soil in all four treatments, leading to the rejection of both hypotheses. Nitrogen concentration and N stocks to 30cm depth increased significantly over the 18years, with no difference among treatments. Conclusion Pasture land use increased soil C storage by ~700kgha−1year−1; however, the increase was confined to the surface soil. Implication The soil C sequestered in this duplex soil is vulnerable to erosion. The co-retained N might have more value from both production and environmental perspectives.

Context Crop production is one of the agricultural sectors most vulnerable to climate change. In order to minimise risks, innovative technologies and management strategies are continually being developed. Early sowing is a strategy used in wheat production; however, with irregular rainfall patterns, false breaks can occur. Aims We sought to determine the optimal volume of autumn-break rainfall for the start of season, and whether formation of a larger rhizosheath (i.e. the thick layer of soil adhering to roots) can buffer wheat seedlings from false-break conditions, thereby keeping plants alive until the next rainfall. Methods In glasshouse experiments, six varieties of common wheat (Triticum aestivum L.), two with contrasting rhizosheath-forming ability and the other four untested, were grown on two soil types (Kandosol and Vertosol) under simulated autumn-break rainfall and false-break durations. Rhizosheath size and plant establishment traits were measured. Key results The ability to form large rhizosheaths explained ~80% of the variability in crop establishment under various scenarios of false-break conditions. Comparative growth performance of the cultivars forming the largest (cv. Flanker) and smallest (cv. Westonia) rhizosheaths showed that they were largely similar for the first 28days of drought but differed significantly thereafter. Flanker was progressively better able to establish as false-break duration increased and showed significantly greater tiller and leaf production than Westonia. Conclusions We demonstrate that genotype selection for formation of large rhizosheaths can help to reduce plant seedling death under false-break conditions. Implications Although the amount of starting rainfall is critical, cultivars differ significantly with regard to how far they can develop without follow-up rain. Future research is suggested for a field-scale study of the potential for selection for larger rhizosheaths to improve wheat crop establishment under harsh conditions.

There is current need for objective measures of sciatic nerve mobility in patients with sciatic‐type pain. The objective of the study was to assess the feasibility and reliability of ultrasound elastography to quantify sciatic nerve displacement and shear strain at the sciatic nerve–hamstring muscle interface during active and passive knee extension‐flexion exercises performed while sitting in healthy people. Ultrasound elastography showed excellent intrarater within‐session reliability for assessing sciatic nerve displacement and sciatic nerve–hamstring muscle interface shear strain during active knee extension‐flexion exercises. These findings will inform similar future work conducted in patients with sciatic‐type pain.

ABSTRACTWhen the abundance of ship rats (Rattus rattus) is reduced, sympatric house mice (Mus musculus) are released from constraints of food shortage, intimidation or predation. As a result, mice may become either more abundant or more active and detectable. To distinguish between these effects, we monitored mice at eight sites within Pureora Forest Park during periods of rat removal and non-removal, and supplemented food in mouse-specific feeders to half of the sites. We used live-trapping to estimate mouse relative abundance, and tracking tunnels to detect activity. Mouse relative abundance increased when rats were removed, which correlated with increased mouse activity in tracking tunnels. Analysis of mouse capture probability showed that although rat population levels predominantly influenced mouse relative abundance, mouse detectability was also affected at a subtler level. Fluctuations in mouse relative abundance were driven by immigration, and there was evidence that mice were food-limited in the presence of abundant rats. However, this effect was not offset by supplementing food, so it is unlikely that exploitation competition alone limits mice in the presence of rats. Instead, when ship rats were abundant the danger to mice was likely to have limited their foraging opportunities. Evidence of direct predation of mice by ship rats was observed, but it is unclear what role direct predation plays in determining mouse abundance relative to risk effects.