Simon McDonald

Integrating spatially referenced social and biophysical data to explore landholder responses to dryland salinity in Australia

Researchers attempting to integrate socio-economic data in watershed planning often draw on nationally collected census data. However, there are critical limitations to the usefulness of this type of data for decision makers operating at the watershed scale. In this paper we demonstrate the relevance of spatially referenced socio-economic data collected using mail surveys to random selections of rural landholders. The issue explored was dryland salinity management in two large watersheds in the Murray-Darling Basin of south-eastern Australia. Contrary to the assumptions underlying public policy in Australia, but consistent with the literature on farmer knowledge, comparisons of expert maps and landholder identified salinity sites suggested that landholders in these watersheds had excellent knowledge of the current extent of salinity on their property. Our research also suggested that salinity education was a sound investment by governments. At the same time, the expert maps failed to predict half of the saline affected sites identified by landholders. Accurately mapping the extent of salinity would seem a first step in addressing this nationally significant land degradation issue.

Effects of leaf age and psyllid damage on the spectral reflectance properties of Eucalyptus saligna foliage

Leaf chlorophyll content is influenced directly by many environmental stress factors. Because leaf pigment absorption is wavelength dependent, numerous narrow-band reflectance-based indices have been proposed as a means of assessing foliar health and condition. Chlorophyll content, however, also varies with leaf developmental stage. In this study, a range of morphological and physiological traits including insect damage, relative chlorophyll content (SPAD values), chlorophyll fluorescence (Fv/Fm) and reflectance spectra was measured of leaves sampled from mature Eucalyptus saligna. Relative differences among three leaf-age cohorts were compared with differences obtained from mature leaves that were either healthy or infested with the psyllid Glycaspis baileyi. Differences in relative chlorophyll content were greater between immature and mature foliage than between damaged and healthy mature leaves. These differences were confirmed in the comparisons of reflectance spectra and indices. As many eucalypt species have opportunistic crown phenology and long-lived leaves, leaf-age composition of crowns needs to be taken into account when applying reflectance-based indices to assess foliar condition of eucalypts.

A geographical analysis of speech-language pathology services to support multilingual children

Abstract The speech-language pathology workforce strives to provide equitable, quality services to multilingual people. However, the extent to which this is being achieved is unknown. Participants in this study were 2849 members of Speech Pathology Australia and 4386 children in the Birth cohort of the Longitudinal Study of Australian Children (LSAC). Statistical and geospatial analyses were undertaken to identify the linguistic diversity and geographical distribution of Australian speech-language pathology services and Australian children. One fifth of services offered by Speech Pathology Australia members (20.2%) were available in a language other than English. Services were most commonly offered in Australian Sign Language (Auslan) (4.3%), French (3.1%), Italian (2.2%), Greek (1.6%), and Cantonese (1.5%). Among 4–5-year-old children in the nationally representative LSAC, 15.3% regularly spoke and/or understood a language other than English. The most common languages spoken by the children were Arabic (1.5%), Italian (1.2%), Greek (0.9%), Spanish (0.9%), and Vietnamese (0.9%). There was a mismatch between the location of and languages in which multilingual services were offered, and the location of and languages spoken by children. These findings highlight the need for SLPs to be culturally competent in providing equitable services to all clients, regardless of the languages they speak.

Ecology of the red fox (Vulpes vulpes) in an agricultural landscape. 2. Home range and movements

The red fox (Vulpes vulpes) is a major predator of Australian wildlife and livestock, but relatively few data exist on fox home-range size and movements in agricultural landscapes. We used radio-telemetry to measure variability in fox home-range size and overlap, and to quantify nightly movements in farmland in south-eastern Australia. Home-range estimates were calculated using the Minimum Convex Polygon (MCP) and Kernel Contours methods. Fourteen foxes were radio-tracked, with home-range size varying from 287 to 3574 ha (mean = 1177 ha, ±920 ha (s.d.), n = 10 foxes) based on the 100% MCP and 151–3196 ha (mean = 639 ha, ± 930 ha (s.d.), n = 10 foxes) based on 95% Kernel. Home-range overlap was greater between subadults than adult foxes; especially at the core home-range level where adult home ranges were virtually exclusive. The average (minimum) area covered by adult foxes during a 12-h nightly period was 383 ha (±347 ha (s.d.), range = 136–1446 ha, n = 4 foxes). The minimum (straight-line) distance travelled by adult foxes during a night was 4.8–16 km (mean = 9.4 km, ± 3.7 km (s.d.), n = 4 foxes). Through continuous radio-tracking, we found that foxes habitually travel over the same ground when moving between foci of interest. Our results improve understanding of fox ranging behaviour in the agricultural landscapes of southern Australia.

Social Acceptability of a Duty of Care for Biodiversity

Biodiversity in Australia continues to decline despite substantial government efforts to promote conservation. A statutory duty of care for biodiversity could promote positive outcomes and complement existing regulatory and voluntary approaches. Interest in a duty of care has been persistent, but progress elusive. Two inter-related issues around the social acceptability of a statutory duty of care are impeding progress: (a) the absence of a practical framework to facilitate its implementation, and (b) concerns about the acceptability of a legal instrument to landholders. In this paper, we present research that, for the first time in Australia, addresses the social acceptability of a duty of care for biodiversity, drawing on data from surveys in two Victorian regions. Our findings suggest that there is broad acceptance of ‘duty of care’ as an abstract concept, but diminished support for its detailed implications. Farmers, in particular, are concerned about the potential for wider community input, the prospect of a legally defined instrument, and the use of industry standards as a surrogate measure for compliance with a duty of care. These findings suggest that efforts to introduce a statutory duty of care need to engage farmers closely.

Demographic patterns of a widespread long-lived tree are associated with rainfall and disturbances along rainfall gradients in SE Australia

Predicting species distributions with changing climate has often relied on climatic variables, but increasingly there is recognition that disturbance regimes should also be included in distribution models. We examined how changes in rainfall and disturbances along climatic gradients determined demographic patterns in a widespread and long-lived tree species, Callitris glaucophylla in SE Australia. We examined recruitment since 1950 in relation to annual (200–600 mm) and seasonal (summer, uniform, winter) rainfall gradients, edaphic factors (topography), and disturbance regimes (vertebrate grazing [tenure and species], fire). A switch from recruitment success to failure occurred at 405 mm mean annual rainfall, coincident with a change in grazing regime. Recruitment was lowest on farms with rabbits below 405 mm rainfall (mean = 0–0.89 cohorts) and highest on less-disturbed tenures with no rabbits above 405 mm rainfall (mean = 3.25 cohorts). Moderate levels of recruitment occurred where farms had no rabbits or less disturbed tenures had rabbits above and below 405 mm rainfall (mean = 1.71–1.77 cohorts). These results show that low annual rainfall and high levels of introduced grazing has led to aging, contracting populations, while higher annual rainfall with low levels of grazing has led to younger, expanding populations. This study demonstrates how demographic patterns vary with rainfall and spatial variations in disturbances, which are linked in complex ways to climatic gradients. Predicting changes in tree distribution with climate change requires knowledge of how rainfall and key disturbances (tenure, vertebrate grazing) will shift along climatic gradients.