Regions Of Southern Australia Research Articles

Acacia Pycnantha Gum Exudates Recognised As a Traditional Food in Two Countries May Have Economic Potential

_Acacia pycnantha _is a native tree growing in the southern regions of Australia, particularly South Australia. The tree trunk and branches exude gum, which is most prolific around April (autumn) and can be removed by simply pulling off or cutting, yielding about 10g/tree/year. Approximately 40% of trees have gum available with about 1%, usually mature trees, having significant amounts. Food Standards Australia and New Zealand has recently formed a view that _Acacia pycnantha _gum can be recognised as a traditional food for consumption up to 30g/day in these countries. The economic potential of _Acacia pycnantha_ gum as a food, additive or for other uses, requires further research into increasing the yield/tree and creating demand.

Acacia pycnantha gum exudates recognised as a traditional food in two countries may have economic potential

_Acacia pycnantha _is a native tree growing in the southern regions of Australia, particularly South Australia. The tree trunk and branches exude gum, which is most prolific around April (autumn) and can be removed by simply pulling off or cutting, yielding about 10g/tree/year. Approximately 40% of trees have gum available with about 1%, usually mature trees, having significant amounts. Food Standards Australia and New Zealand has recently formed a view that _Acacia pycnantha _gum can be recognised as a traditional food for consumption up to 30g/day in these countries. The economic potential of _Acacia pycnantha_ gum as a food, additive or for other uses, requires further research into increasing the yield/tree and creating demand.

Impact of Zonal and Meridional Atmospheric Flow on Surface Climate and Extremes in the Southern Hemisphere

Abstract The Southern Annular Mode (SAM) describes the annular or zonal component of the large-scale atmospheric circulation in the Southern Hemisphere (SH) extratropics and influences surface climate across the SH. Although this annular flow is dominant in austral summer, in other seasons considerable zonal asymmetries are evident, reflecting a zonal wave 3 (ZW3) pattern. We define an index representing asymmetric flow using the first two leading modes of meridional wind variability in the SH. Two orthogonal ZW3 indices are used together to capture longitudinal shifts in the wave train and their connection to tropical convection. We compare the impacts of the SAM and ZW3 on surface climate by examining composites of temperature and precipitation fields during each season. Impacts on mean and extreme surface climates are assessed. We find that the SAM and ZW3 are not clearly separated modes, but rather, ZW3 modulates the impact of the SAM across the midlatitudes. The SAM influence on regional temperature and precipitation is similar for both mean impacts and extremes. The ZW3 influence on extremes is more varied across indices and does not always reflect the ZW3 impact on mean fields. Notably, amplified ZW3 activity has a significant influence on the number of midlatitude fronts and frontal rainfall, highlighting the importance of considering ZW3 when exploring the surface climate impacts of large-scale SH circulation states, particularly for nonsummer seasons. Significance Statement Variations in the strength and position of the midlatitude westerly winds have a strong influence on surface climates. While these winds are predominantly zonally symmetric in the Southern Hemisphere, few studies to date have explored the role of the asymmetric component of this circulation, particularly for seasons outside of summer. By defining two new indices of meridional circulation, this study reveals new important impacts on temperature, rainfall, and the likelihood of extreme climates in regions of southern Australia and South America, and sea ice regions around Antarctica. These findings question the validity of considering only zonal-mean winds for climate studies of the Southern Hemisphere and have important implications for the seasonal forecasting and predictability of extreme climate events in the near future.

Characterisation of physical properties of prepared cane from soft-cane varieties

Concerns have been raised that many sugarcane varieties in the development pipeline, particularly in the Central and Southern regions of Australia, have fiber quality classified as soft, with some soft enough to cause processing problems in the factory. The main issues have been feeding off the cane through the milling train and high bagasse moisture contents, causing subsequent combustion issues and low steam pressure at the boiler station. These cane varieties are usually designated as ‘soft-canes’, and their presence had been noted for at least 60 years. An attractive trait is their relatively high sugar yield per hectare. Some other general characteristics have been reported as often (but not always) having relatively low fiber content and being easier to prepare by the shredder, resulting in a larger number of smaller sized particles in the prepared cane. During the development of new cane varieties, Sugar Research Australia carries out tests for ‘fiber quality’. Experiments were carried out at Isis Central Mill to understand and improve the processing of existing soft-cane varieties. During the 2019 crushing season, a pilot-scale shredder was used to simulate the effect of shredder settings (speed and grid setting) that are known to affect preparation levels. Four existing soft-cane varieties (SRA1A, SRA4A, SRA11A and QN04-1643) were tested, along with Q208A that provided a reference as a middle-of-the-range variety (perceived to be neither a soft nor hard cane). The prepared cane produced was tested for fiber quality at the SRA fiber quality laboratory in Bundaberg. As measured at the factory, the preparation level and two physical properties (compression and permeability) were identified as important for the milling process. All the cane varieties responded similarly to speed and grid setting, with the soft-canes being part of a continuum, not a separate subset. The overall conclusion was that adjusting shredder speed and grid setting can control preparation and potentially address feeding problems at the milling train through improved control strategies.

An economic assessment of options for operating within plantation forestry water entitlements and tightening cap and trade policy

AbstractThe Green Triangle (GT) region of southern Australia is one of only two jurisdictions globally to licence plantation forestry's groundwater use. In response to declines in groundwater resources caused by historical plantation expansion, reductions in forest water allocations (~50%) are likely for some parts of the region, presenting novel challenges for forest managers in maintaining revenues and timber flows. This article presents a mathematical programming model evaluation of water trade opportunities for plantation forest owners to adapt to reduced water entitlements and explores how tightening groundwater policy could affect forestry returns and land use mix for the region. Results suggest that even absent opportunity to sell water, relatively limited 11% reduction in return could be expected for a large (−50%) water entitlement and (−48%) land‐use change out of forestry. Results suggest that opportunities for forestry companies to sell water entitlements may allow them to maintain or even increase combined returns from forestry and water sales. Whilst the results highlight the adaptive capacity of the plantation forestry sector to operate within reduced water entitlement, a significant sectoral and regional economy adjustment would be likely. The discussion focusses on the potential to realise optimisation model‐identified adaptation opportunities accounting for real‐world thin markets, transaction costs and market friction.

Climate, currents and species traits contribute to early stages of marine species redistribution

Anthropogenic climate change is causing a rapid redistribution of life on Earth, particularly in the ocean, with profound implications for humans. Yet warming-driven range shifts are known to be influenced by a variety of factors whose combined effects are still little understood. Here, we use scientist-verified out-of-range observations from a national citizen-science initiative to assess the combined effect of long-term warming, climate extremes (i.e., heatwaves and cold spells), ocean currents, and species traits on early stages of marine range extensions in two warming ‘hotspot’ regions of southern Australia. We find effects of warming to be contingent upon complex interactions with the strength of ocean currents and their mutual directional agreement, as well as species traits. Our study represents the most comprehensive account to date of factors driving early stages of marine species redistributions, providing important evidence for the assessment of the vulnerability of marine species distributions to climate change.

Phytochemistry and Pharmacology of Ceratonia siliqua L. leaves

Ceratonia siliqua commonly known as carob belongs to the Fabaceae (Legumunosae). Its original habitats are the western parts of Asia, but after its domestication, it spread to all Mediterranean Basin and then to the western shores of the Americas, South Africa and southern regions of Australia. This review is devoted to health benefits of the carob leaf which are attributed in particular to its phytochemical constituents such as quercetin and gallic, coumaric, chlorogenic acids. Extracts from carob leaves (CLs) have been investigated for their biological activities including anti-cholestinerase, anti-inflammatory, Antidiarrhoeal, anti-tumor, anti-cancer, antimicrobial, hepatoprotective, nephroprotective, antidiabetic and antiobesity as well as phytochemical profile and nutritive value of the CLs. Hence, extracts from Ceratonia siliqua L. leaves, a huge source of bioactive compounds, exhibit a panoply of biological properties. Thus, leaves can be used as a functional food or as a phyto-pharmaceutical herbal-type product. However, it would be wise to undertake clinical trials to prove the efficacy of carob leaf extracts.

Single-step genomic BLUP enables joint analysis of disconnected breeding programs: an example with Eucalyptus globulus Labill.

Single-step GBLUP (HBLUP) efficiently combines genomic, pedigree, and phenotypic information for holistic genetic analyses of disjunct breeding populations. We combined data from two independent multigenerational Eucalyptus globulus breeding populations to provide direct comparisons across the programs and indirect predictions in environments where pedigreed families had not been evaluated. Despite few known pedigree connections between the programs, genomic relationships provided the connectivity required to create a unified relationship matrix, H, which was used to compare pedigree-based and HBLUP models. Stem volume data from 48 sites spread across three regions of southern Australia and wood quality data across 20 sites provided comparisons of model accuracy. Genotyping proved valuable for correcting pedigree errors and HBLUP more precisely defines relationships within and among populations, with relationships among the genotyped individuals used to connect the pedigrees of the two programs. Cryptic relationships among the native range populations provided evidence of population structure and evidence of the origin of landrace populations. HBLUP across programs improved the prediction accuracy of parents and genotyped individuals and enabled breeding value predictions to be directly compared and inferred in regions where little to no testing has been undertaken. The impact of incorporating genetic groups in the estimation of H will further align traditional genetic evaluation pipelines with approaches that incorporate marker-derived relationships into prediction models.

Cryptic diversity found in Didymellaceae from Australian native legumes.

Ascochyta koolunga (Didymellaceae, Pleosporales) was first described in 2009 (as Phoma koolunga) and identified as the causal agent of Ascochyta blight of Pisum sativum (field pea) in South Australia. Since then A. koolunga has not been reported anywhere else in the world, and its origins and occurrence on other legume (Fabaceae) species remains unknown. Blight and leaf spot diseases of Australian native, pasture and naturalised legumes were studied to investigate a possible native origin of A. koolunga.Ascochyta koolunga was not detected on native, naturalised or pasture legumes that had leaf spot symptoms, in any of the studied regions in southern Australia, and only one isolate was recovered from P. sativum. However, we isolated five novel species in the Didymellaceae from leaf spots of Australian native legumes from commercial field pea regions throughout southern Australia. The novel species were classified on the basis of morphology and phylogenetic analyses of the internal transcribed spacer region and part of the RNA polymerase II subunit B gene region. Three of these species, Nothophoma garlbiwalawardasp. nov., Nothophoma naiawusp. nov. and Nothophoma ngayawangsp. nov., were isolated from Senna artemisioides. The other species described here are Epicoccum djirangnandirisp. nov. from Swainsona galegifolia and Neodidymelliopsis tinkyukukusp. nov. from Hardenbergia violacea. In addition, we report three new host-pathogen associations in Australia, namely Didymella pinodes on S. artemisioides and Vicia cracca, and D. lethalis on Lathyrus tingitanus. This is also the first report of Didymella prosopidis in Australia.

Not all urban landscapes are the same: interactions between urban land use and stress in a large herbivorous mammal.

Urbanization significantly impacts the health and viability of wildlife populations yet it is not well understood how urban landscapes differ from non-urban landscapes with regard to their effects on wildlife. This study investigated the physiological response of eastern grey kangaroos (Macropus giganteus) to land use at a landscape scale. Using fecal glucocorticoid metabolites (FGM) we compared stress levels of kangaroo populations in urban and non-urban environments. We modeled FGM concentrations from 24 kangaroo populations against land use (urban or non-urban) and other anthropogenic and environmental factors, using a linear modeling approach. We found that land use was a significant predictor of FGM concentrations in eastern grey kangaroos with significant differences in concentrations between urban and non-urban populations. However, the direction of the relationship differed between northern and southern regions of Australia. In the northern study sites, kangaroos in urban areas had significantly higher FGM levels than their non-urban counterparts. In contrast, in southern sites, where kangaroos occur in high densities in many urban areas, urban kangaroos had lower FGM concentrations than non-urban kangaroos. Rainfall and temperature were also significant predictors of FGM and the direction of the relationship was consistent across both regions. These results are consistent with the contrasting abundance and persistence of kangaroo populations within the urban matrix between the two study regions. In the northern region many populations have declined over the last two decades and are fragmented, also occurring at lower densities than in southern sites. Our study indicates that it is the characteristics of urban environments, rather than the urban environment per se, which determines the extent of impacts of urbanization on kangaroos. This research provides insights into how the design of urban landscapes can influence large mammal populations.

Resistance to very-long-chain fatty-acid (VLCFA)-inhibiting herbicides in multiple field-selected rigid ryegrass (Lolium rigidum) populations

AbstractFive populations of rigid ryegrass (Lolium rigidumGaudin) from fields across cropping regions in southern Australia were suspected of having resistance to thiocarbamates, chloroacetamides, and sulfonylisoxazoline herbicides. Resistant (R) populations 375-14, 198-15, 16.2, EP162, RAC1, and A18 and two susceptible (S) populations (SLR4 and VLR1) were included in a dose–response study. All suspected R populations expressed resistance to one or all herbicides (thiocarbamates, chloroacetamides, and pyroxasulfone). Population 198-15 exhibited the highest LD50to triallate (44.7-fold), prosulfocarb (45.7-fold),S-metolachlor (31.5-fold), and metazachlor (27.2-fold) compared with the S populations. Populations 198-15 and 375-14 were also resistant to pyroxasulfone (13.5- and 14.9-fold) compared with the S populations, as was population EP162. This study documents the first case of field-evolved resistance to thiocarbamate, chloroacetamide, and sulfonylisoxazoline herbicides inL. rigidum.

Pollen analysis of Australian honey.

Pollen analysis is widely used to verify the geographic origin of honeys, but has never been employed in Australia. In this study, we analysed the pollen content of 173 unblended honey samples sourced from most of the commercial honey producing regions in southern Australia. Southern Australian vegetation is dominated by Eucalyptus (Myrtaceae) forests and, as expected, most Australian honeys are palynologically dominated by Eucalyptus, while other important components include Myrtaceae taxa such as Corymbia/Angophora and the tribe Leptospermeae; plus Brassicaceae, Echium, Macadamia, and Acacia. An important feature of the honeys is the number of Myrtaceae pollen morphotypes per sample, which is generally high (mean = 4.6) compared to honeys produced outside of Australia, including Eucalyptus honeys produced in the Mediterranean region, and honeys produced in South America, which has its own rich indigenous Myrtaceae flora. In the latter regions, the number of Myrtaceae morphotypes is apparently generally ≤2. A high number of Myrtaceae morphotypes may be a feasible criterion for authenticating the origin of Australian honeys, since most Australian honey is produced by honey bees mainly working indigenous floral resources. Myrtaceae morphotype diversity is a convenient melissopalynological measure that could be applied even where detailed knowledge of the pollen morphology of the many component genera and species is absent. Palynological criteria developed in Europe for authenticating Eucalyptus honeys should not be relied upon for Australian honeys, since those criteria are not based on samples of Australian honey.

Three New Gastropods (Cypraeidae, Fasciolariidae, and Volutidae) from the Great Australian Bight

Three new gastropods, belonging to the families Cypraeidae, Fasciolariidae, and Volutidae, are described from the Great Australian Bight region of southern Australia. These new taxa, which encompass two new subspecies and a new species, include: Austrocypraea reevei bishopi new subspecies (Cypraeidae), Fusinus bishopi new species (Fasciolariidae), and Mitraelyria mitraeformis grockeae new subspecies (Volutidae).

Floral morphology of Eucalyptus leucoxylon (Myrtaceae) facilitates pollination by lorikeet (Aves: Psittacidae) tongues

Bird pollination is particularly common and widespread in the southern regions of Australia. Despite some eucalypts being heavily frequented by birds, they are usually considered to have a generalist pollination system because of their apparently unspecialised floral morphology. A few species possess protandrous anthers that dehisce within a tightly furled dome of filaments. We hypothesised that this facilitates pollen transport via the brush tongues of lorikeets. Using Eucalyptus leucoxylon F.Muell. and five captive rainbow lorikeets (Trichoglossus hematodus) as a model, we demonstrated that lorikeets remove significant quantities of pollen from flowers with inflexed filaments in a short time (30 min), compared with bagged control flowers (Mann–Whitney U test, Z = 165.4, d.f. = 29, P = 0.008). Some of this pollen is deposited on stigmas by the tongue, which is the organ that most regularly and reliably contacts stigmas. The mean number of pollen grains deposited on stigmas by each bird was as high as 121.2. Adhesive tape contacted by the tongue during foraging removed up to 2104 pollen grains, which was significantly greater than for uncontacted control tape (Mann–Whitney U test, Z = 110, d.f. = 21, P < 0.001). Scanning electron micrograph imaging of a lorikeet tongue showed many pollen grains that had been transferred onto its keratin papillae, which is likely to have contributed to high carryover rates by retaining pollen for a substantial amount of time. Minimal pollen is available for generalist pollination once the filaments unfurl. It appears highly unlikely that insects are able to access pollen from these male-phase flowers and inflexed filaments may therefore fulfil an exclusionary role.

Current Understanding of Acute Bovine Liver Disease in Australia.

Acute bovine liver disease (ABLD) is a hepatotoxicity principally of cattle which occurs in southern regions of Australia. Severely affected animals undergo rapid clinical progression with mortalities often occurring prior to the recognition of clinical signs. Less severely affected animals develop photosensitization and a proportion can develop liver failure. The characteristic histopathological lesion in acute fatal cases is severe, with acute necrosis of periportal hepatocytes with hemorrhage into the necrotic areas. Currently there are a small number of toxins that are known to cause periportal necrosis in cattle, although none of these have so far been linked to ABLD. Furthermore, ABLD has frequently been associated with the presence of rough dog’s tail grass (Cynosurus echinatus) and Drechslera spp. fungi in the pasture system, but it is currently unknown if these are etiological factors. Much of the knowledge about ABLD is contained within case reports, with very little experimental research investigating the specific cause(s). This review provides an overview of the current and most recently published knowledge of ABLD. It also draws on wider research and unpublished reports to suggest possible fungi and mycotoxins that may give rise to ABLD.

Carbon uptake and water use in woodlands and forests in southern Australia during an extreme heat wave event in the “Angry Summer” of 2012/2013

Abstract. As a result of climate change warmer temperatures are projected through the 21st century and are already increasing above modelled predictions. Apart from increases in the mean, warm/hot temperature extremes are expected to become more prevalent in the future, along with an increase in the frequency of droughts. It is crucial to better understand the response of terrestrial ecosystems to such temperature extremes for predicting land-surface feedbacks in a changing climate. While land-surface feedbacks in drought conditions and during heat waves have been reported from Europe and the US, direct observations of the impact of such extremes on the carbon and water cycles in Australia have been lacking. During the 2012/2013 summer, Australia experienced a record-breaking heat wave with an exceptional spatial extent that lasted for several weeks. In this study we synthesised eddy-covariance measurements from seven woodlands and one forest site across three biogeographic regions in southern Australia. These observations were combined with model results from BIOS2 (Haverd et al., 2013a, b) to investigate the effect of the summer heat wave on the carbon and water exchange of terrestrial ecosystems which are known for their resilience toward hot and dry conditions. We found that water-limited woodland and energy-limited forest ecosystems responded differently to the heat wave. During the most intense part of the heat wave, the woodlands experienced decreased latent heat flux (23 % of background value), increased Bowen ratio (154 %) and reduced carbon uptake (60 %). At the same time the forest ecosystem showed increased latent heat flux (151 %), reduced Bowen ratio (19 %) and increased carbon uptake (112 %). Higher temperatures caused increased ecosystem respiration at all sites (up to 139 %). During daytime all ecosystems remained carbon sinks, but carbon uptake was reduced in magnitude. The number of hours during which the ecosystem acted as a carbon sink was also reduced, which switched the woodlands into a carbon source on a daily average. Precipitation occurred after the first, most intense part of the heat wave, and the subsequent cooler temperatures in the temperate woodlands led to recovery of the carbon sink, decreased the Bowen ratio (65 %) and hence increased evaporative cooling. Gross primary productivity in the woodlands recovered quickly with precipitation and cooler temperatures but respiration remained high. While the forest proved relatively resilient to this short-term heat extreme the response of the woodlands is the first direct evidence that the carbon sinks of large areas of Australia may not be sustainable in a future climate with an increased number, intensity and duration of heat waves.

Reconfiguring agriculture through the relocation of production systems for water, environment and food security under climate change

SUMMARYThe prospect of climate change has revived both fears of food insecurity and its corollary, market opportunities for agricultural production. In Australia, with its long history of state-sponsored agricultural development, there is renewed interest in the agricultural development of tropical and sub-tropical northern regions. Climate projections suggest that there will be less water available to the main irrigation systems of the eastern central and southern regions of Australia, while net rainfall could be sustained or even increase in the northern areas. Hence, there could be more intensive use of northern agricultural areas, with the relocation of some production of economically important commodities such as vegetables, rice and cotton. The problem is that the expansion of cropping in northern Australia has been constrained by agronomic and economic considerations.The present paper examines the economics, at both farm and regional level, of relocating some cotton production from the east-central irrigation areas to the north where there is an existing irrigation scheme together with some industry and individual interest in such relocation. Integrated modelling and expert knowledge are used to examine this example of prospective climate change adaptation. Farm-level simulations show that without adaptation, overall gross margins will decrease under a combination of climate change and reduction in water availability. A dynamic regional Computable General Equilibrium model is used to explore two scenarios of relocating cotton production from south east Queensland, to sugar-dominated areas in northern Queensland. Overall, an increase in real economic output and real income was realized when some cotton production was relocated to sugar cane fallow land/new land. There were, however, large negative effects on regional economies where cotton production displaced sugar cane. It is concluded that even excluding the agronomic uncertainties, which are not examined here, there is unlikely to be significant market-driven relocation of cotton production.

Keystone resources available to wild pollinators in a winter‐flowering tree crop plantation

Abstract Homogeneous tree crop plantations can adversely impact wild pollinator communities by limiting the temporal continuity of food and the availability of nesting sites. Identifying how structural differences between plantations and natural vegetation influence pollinator communities is necessary for ecological management of agroecosystems. Communities of potential wild pollinators (native bees, wasps, flies) were compared between monoculture almond plantations and native vegetation in a semi‐arid region of southern Australia, before, during and after the late winter almond flowering period. Abundance and richness of each insect group were related to site heterogeneity and keystone structural resources at each site, focusing on food and nesting resources. Relationships with site heterogeneity varied between taxa and across months. Native bee abundance and richness were strongly associated with specific keystone resources, despite showing no association with site heterogeneity. The present study highlights the value of focusing on biologically meaningful resources when investigating relationships between insects and habitat, rather than on generalized heterogeneity metrics. The results suggest that maintaining keystone resources in agroecosystems can support the conservation of insects and ecosystem services, especially in areas where homogeneous agricultural systems overlap dynamic natural ecosystems.

Developing the role of perennial forages for crop–livestock farms: a strategic multi-disciplinary approach

Developing new and improved grazing systems for crop–livestock farms where crop production is the major driver of farm management decisions presents a unique research and development challenge. In southern Australia, a substantial proportion of animal production from grazing comes from regions and farms where cropping is the major enterprise. In this paper, we describe a multi-disciplinary farming-systems research approach (EverCrop) aimed at improving farm profitability, risk management and environmental impacts through the development and integration of new grazing options with an emphasis on perennial species. It has been used to analyse and target new opportunities for farmers to benefit from perennial species across dry Mediterranean-type and temperate regions of southern Australia. It integrates field experimentation, on-farm trialling, farmer participatory research, soil–plant–climate biophysical modelling, whole-farm bioeconomic analysis and evaluations of adoptability. Multi-functional roles for summer-active grasses with winter cropping, integration of forage shrubs and establishment of new mixes of perennial grasses in crop rotations to improve farming system performance are identified, along with an analysis of factors likely to affect rate of uptake by farmers.

Public acceptance of plantation forestry: Implications for policy and practice in Australian rural landscape

Plantations are expanding in many parts of the world, often accompanied by public debate. If policy makers and plantation managers seek to better align land use policy with social values and to reduce social conflict, they require a clear understanding of public expectations of land use, and the kinds of plantations that are socially acceptable. This paper presents results of a large postal survey (n=2167) conducted in two regions of southern Australia. Residents of Tasmania and southwest Western Australia reported their acceptance of a range of plantations characterised with regard to factors such as type of product, location and size of plantation and ownership. Participants also indicated their beliefs about the impacts of commercial eucalypt plantations. The results showed that participants generally prioritised public good outcomes over individual gains from rural land use, and tended to view plantations as providing more benefits for owners than positive outcomes for the environment or the broader community. Plantations were more acceptable when grown for timber rather than pulp, when planted in areas with good water availability and poorer soils, when planted on part of a property rather than a whole property, and when owned by an individual landholder rather than a plantation company. Results are interpreted to highlight the implications for plantation policy and management in the Australian context, and to illustrate how social research can inform these practices.