Assessing the impact of drought and forestry on streamflows in south-eastern Australia using a physically based hydrological model

An increase in plantation forestry has been linked to a reduction in streamflows in some catchments. Quantifying the relative contribution of this land-use change on streamflows can be complex when those changes occur during weather extremes such as drought. In this study, the Soil and Water Assessment Tool (SWAT) model was applied to two sub-catchments in south-eastern Australia which have seen the introduction and establishment of plantation land use in the past 15 years, coinciding with severe drought (1997–2009). The models were both manually and auto-calibrated and produced very good fits to observed streamflow data during both calibration (1980–1991) and validation (1992–2009) periods. Sensitivity analyses indicated that the models were most sensitive to soil and groundwater parameterisation. Analysis of drought conditions on streamflows showed significant declines from long-term average streamflows, while assessment of baseflow contributions by the models indicated a mix of over- and underestimation depending on catchment and season. The modelled introduction of plantation forestry did not significantly change streamflows for a scenario which did not include the land-use change, suggesting that the modelled land-use change in the catchments was not sufficiently extensive to have an impact on streamflows despite simulating actual rates of change. The SWAT models developed by this study will be invaluable as a basis for future use in regional climate-change studies and for the assessment of land management and land-use change impact on streamflows.

‘On my ground’: Indigenous farmers at New Norcia 1860s-1900s

These words were penned in 1867 by Father Venancio Garrido, a Benedictine monk at New Norcia Aboriginal mission in Western Australia (see Map 4.1). They form part of his lengthy report on the mission which was requested by the Colonial Secretary to be forwarded to the Aborigines Protection Society in London. In 1871 Father Garrido’s report was collated alongside other ‘information’ about Aborigines in Western Australia that had been collected by missionaries and government agents, and was printed by the government printer. The above statement suggests two issues which I will draw out in this chapter: the Aboriginal residents at New Norcia had a strong sense of right and wrong; and the Benedictine community at New Norcia considered them to be the original owners of the land which was, in 1867, increasingly occupied by pastoralists.

Potential for water-resource infrastructure to act as refuge habitat

Permanent sources of natural water are expected to decline in Mediterranean-climate regions under future climate change. Therefore, stable water bodies that act as refuge habitats will become increasingly important to the maintenance of freshwater biodiversity. Man-made water bodies such as those associated with water-resource infrastructure could contribute to the available refuge habitat but little is known about fish, zooplankton and frog assemblages in such water bodies. We quantified the diversity and abundance of fish, zooplankton and frogs that reside within raw water storages and water reclamation plants and compared them to assemblages from nearby natural water bodies over a total of 19 water bodies.Overall, the faunal assemblages within the man-made water bodies showed similarities to the nearby natural water bodies with very few differences found among the three water body types. Diversity of available substrates and of submerged and emergent macrophytes were the habitat variables best correlated with diverse faunal assemblages. This study suggests that the faunal assemblages within raw water storages and water reclamation plants resemble those found within nearby natural water bodies and that there is therefore potential for water-resource infrastructure to act as an important refuge habitat during drought. Furthermore, small changes in the management of these storages to maximise habitat diversity could increase the value of the refuge, complementing their role in water-resource delivery.

Limitations to the feasibility of using hypolimnetic releases to create refuges for riverine species in response to stream warming

Given predicted increases associated with human-induced climate change, stream temperatures are likely to approach upper tolerance limits of aquatic biota within the coming decades. Little information is available regarding thermal tolerance limits of lotic fauna or mechanisms allowing fauna to persist following high temperature events (e.g. use of thermal refuges). Cold-water refuges can facilitate survival of fish in the Northern Hemisphere, but little evidence of similar refuges exists elsewhere.Planned releases of hypolimnetic, or a mixture of top and bottom, waters from reservoirs have recently been touted as a novel method to potentially ameliorate extreme temperature events. However, the feasibility of this technique has not been fully discussed in the published literature. Therefore, we present a literature review, an analysis of thermal data for some large dams in southern Australia in relation to known thermal tolerances of native fauna, and an assessment of current management practices regarding the technique. We show that hypolimnetic releases have variable impacts on water temperatures downstream of a dam, depending on size, off-take infrastructure and management practices but, even where there is an effect, knowledge gaps are too numerous for this technique to be currently feasible. Furthermore, hypolimnetic releases generally evoke negative connotations among natural resource managers, due to the occurrence of cold-water shock in some species. If knowledge gaps and limitations can be addressed, it is possible that the technique may be considered in future, so we present potential tools for future assessment, capacities and limitations and discuss potential scenarios where environmental managers might consider this technique.

An internet-supported physical activity intervention delivered in secondary schools located in low socio-economic status communities : study protocol for the activity and motivation in physical education (AMPED) cluster randomized controlled trial

BACKGROUND: School-based physical education is an important public health initiative as it has the potential to provide students with regular opportunities to participate in moderate-to-vigorous physical activity (MVPA). Unfortunately, in many physical education lessons students do not engage in sufficient MVPA to achieve health benefits. In this trial we will test the efficacy of a teacher professional development intervention, delivered partially via the Internet, on secondary school students' MVPA during physical education lessons. Teaching strategies covered in this training are designed to (i) maximize opportunities for students to be physically active during lessons and (ii) enhance students' autonomous motivation towards physical activity. METHOD: A two-arm cluster randomized controlled trial with allocation at the school level (intervention vs. usual care control). Teachers and Year 8 students in government-funded secondary schools in low socio-economic areas of the Western Sydney region of Australia will be eligible to participate. During the main portion of the intervention (6 months), teachers will participate in two workshops and complete two implementation tasks at their school. Implementation tasks will involve video-based self-reflection via the project's Web 2.0 platform and an individualized feedback meeting with a project mentor. Each intervention school will also complete two group peer-mentoring sessions at their school (one per term) in which they will discuss implementation with members of their school physical education staff. In the booster period (3 months), teachers will complete a half-day workshop at their school, plus one online implementation task, and a group mentoring session at their school. Throughout the entire intervention period (main intervention plus booster period), teachers will have access to online resources. Data collection will include baseline, post-intervention (7-8 months after baseline) and maintenance phase (14-15 months after baseline) assessments. Research assistants blinded to group allocation will collect all data. The primary outcome will be the proportion of physical education lesson time that students spend in MVPA. Secondary outcomes will include leisure-time physical activity, subjective well-being, and motivation towards physical activity.
DISCUSSION: The provision of an online training platform for teachers could help facilitate more widespread dissemination of evidence-based interventions compared with programs that rely exclusively on face-to-face training.

Establishing precise estimates of abundance in patchy habitats of the marine nearshore

Exploratory investigations of optimal sampling designs are a critical component of the decision-making process in ecology where inherent natural variation can lead to erroneous conclusions if left unexamined. Pilot studies and exploratory analyses that investigate the precision of sampling regimes may reduce the chances of erroneous results and can be used to optimise processing time in larger ecological research programs. In our study, we calculated optimal precision estimates for sampling macroinvertebrates and ichthyofauna in surf-zone wrack accumulations by investigating the precision of the mean for sub-samples of seine nets and also for the number of replicate seine nets to guide future sampling regimes. We discovered that the processing time for individual seine net samples could be reduced by 50% using sub-sampling and that time to process replicate seine net samples could be reduced by 25% while maintaining acceptable precision. In future, we suggest that the use of pilot studies with similar exploratory approaches should be less of an exception and more a critical component of ecological investigations, particularly in under-studied or newly-developing areas of research. Further, these types of exploratory approaches are crucially important in a variety of extremely patchy environments where variability is likely to be high.