Northern Part Of Australia Research Articles

Genetic Diversity Analysis of Indian Salmon, <i>Eleutheronema tetradactylum</i> from South Asian Countries Based on Mitochondrial COI Gene Sequences

Eleutheronema tetradactylum is an important commercial fish species exposed to intense exploitation both in Southeast Asian countries and Northern parts of Australia. Research on the population structure of E. tetradactylum in these coastal waters is substantial in order to ensure sustainable use and appropriate resource management. In this study, genetic variation, diversity and population structure of E. tetradactylum among four FAO fishing areas, along South Asian countries, were evaluated using cytochrome c oxidase subunit I (COI) gene. Totally 30 sequences of COI gene were collected from four FAO fishing areas. Among these 30 individuals, 18 distinct haplotypes were defined. High levels of haplotype diversity (hd = 0.952 ± 0.096) and nucleotide diversity (π = 0.01536 ± 0.00312) were observed in the population within the Bay of Bengal. No haplotype and nucleotide diversity were observed in South China Sea population. Hierarchical analysis of molecular variance (AMOVA) indicated that 0.81% of the genetic variation occurred within the populations, while 7.09% variation occurred among populations. Significant genealogical branches were recognized in North Australian populations (one clade), South China Sea populations (one clade), Arabian Sea and Bay of Bengal populations (one clade) on the neighbor-joining tree. These results suggested that E. tetradactylum populations in FAO fishing areas 51, 57 and 61 have developed different genetic structures. Tests of neutral evolution and mismatch distribution suggest that a population growth of E. tetradactylum may take place in these fishing areas.

Evaluation of the economic feasibility of water harvesting for irrigation in a large semi-arid tropical catchment in northern Australia

There is interest by governments and private organisations in exploring alternative models of irrigation in parts of northern Australia where there has been little irrigation development to date. One alternative is ‘water harvesting’, which is defined here as the practice of pumping or diverting water during streamflow events and either applying directly to a crop or (more commonly) holding water in off-stream storage on a property for later use. This study presents a detailed farm-scale bio-economic analysis of water harvesting using river system modelling to represent the interactions between farm-scale returns, reliability of extraction and scale of development. In doing so the farm-scale viability of irrigation within a whole of catchment is assessed, and uses the Flinders catchment, a large, semi-arid tropical catchment in northern Australia as a case study. Extraction reliability varied spatially across the catchment and decreased with increasing total catchment extraction. The farm-scale profitability of water harvesting enterprises was found to be particularly sensitive to fluctuations in price, reliability of water extraction, discount rate, cost of storage and timing of crop-failure years. For crops requiring off-site processing, the existence of local processing facilities was a major factor. This study also highlighted that for irrigation developments based on water harvesting there is potential for serious mismatches between the timing of streamflow and time at which planting must occur.For the cropping scenarios modelled here for the Flinders catchment it was found that mosaics of irrigation based on water harvesting and off-stream storage are unlikely to be profitable, and short to medium season crops provided the best return, although still negative. This is because land developed for irrigation of short to medium season crops returns no income for six or more months every year, while for permanent cropping the cost of constructing a storage that could provide water for irrigation throughout the year is prohibitively expensive. Assuming an optimal water storage to pump capacity ratio of 5, it was found that if an additional 240GL of water were added to the existing 105GL catchment entitlement, most new irrigators could extract their entitlement in approximately 70 to 80% of years, discounting any environmental or legislative issues that would need to be addressed. At these reliabilities, most high value crops would require high prices to be sustained through the entire investment period (for which there is no historical precedent), to acquire a return equal to inflation. The method and results presented in this manuscript would be useful to water planners and regulators to help inform water allocation, pricing decisions and policy initiatives, particularly where agricultural development may be based on water harvesting.

Genetic analysis of Giardia and Cryptosporidium from people in Northern Australia using PCR-based tools

To date, there has been limited genetic study of the gastrointestinal pathogens Giardia and Cryptosporidium in northern parts of Australia. Here, PCR-based methods were used for the genetic characterization of Giardia and Cryptosporidium from 695 people with histories of gastrointestinal disorders from the tropical North of Australia. Genomic DNAs from fecal samples were subjected to PCR-based analyses of regions from the triose phosphate isomerase (tpi), small subunit (SSU) of the nuclear ribosomal RNA and/or the glycoprotein (gp60) genes. Giardia and Cryptosporidium were detected in 13 and four of the 695 samples, respectively. Giardia duodenalis assemblages A and B were found in 4 (31%) and 9 (69%) of the 13 samples in persons of <9years of age. Cryptosporidium hominis (subgenotype IdA18), Cryptosporidium mink genotype (subgenotype IIA16R1) and C. felis were also identified in single patients of 11–21years of age. Future studies might focus on a comparative study of these and other protists in rural communities in Northern Australia.

Flood-flipped boulders: In-situ cosmogenic nuclide modeling of flood deposits in the monsoon tropics of Australia

During the Quaternary, extreme floods along the Durack River, in the Kimberley, northern Australia, dislodged, transported, and stacked massive meter-sized boulders from the underlying bedrock channel floor. Field evidence identified a population of the boulders to have been overturned after detachment. We measured in situ cosmogenic 10 Be and 26 Al concentrations in six imbricated boulders to constrain the timing of flood events. We present a simple numerical model that simultaneously solves the expressions for the predicted nuclide concentrations from the exposed and hidden surfaces of a flipped boulder to calculate the time since it was overturned. The ability of the model to unequivocally discern whether a boulder was overturned depends on boulder thickness and the site-specific steady-state erosion rate. Of the six boulders sampled, our model successfully determined four finite flip ages, whereas the other two boulders indicated steady state and were either not flipped or flipped sufficiently long ago for the nuclide profile to have returned to steady state. While the two older model ages (ca. 150 ka and ca. 260 ka) are strongly sensitive to assumptions made for the local erosion rate correction, the two younger flip ages, 5.6 ± 1.0 ka and 10.3 ± 1.9 ka, are robust against such corrections. Early to mid-Holocene major floods have been recorded in other parts of northern Australia. We suggest that similar Holocene floods occurred in the Kimberley and that such extreme events may have been widespread in northern Australia in the late Quaternary. Our boulder-flip model can be applicable to similar deposits associated with other extreme events such as paleo-tsunamis.

Predictors of suicides occurring within suicide clusters in Australia, 2004–2008

A number of studies have investigated the presence of suicide clusters, but few have sought to identify risk and protective factors of a suicide occurring within a cluster. We aimed to identify socio-demographic and contextual characteristics of suicide clusters from national and regional analyses of suicide clusters. We searched the National Coroners Information System for all suicides in Australia from 2004 to 2008. Scan statistics were initially used to identify those deaths occurring within a spatial-temporal suicide cluster during the period. We then used logistic regression and generalized estimation equations to estimate the odds of each suicide occurring within a cluster differed by sex, age, marital status, employment status, Indigenous status, method of suicide and location. We identified 258 suicides out of 10,176 suicides during the period that we classified as being within a suicide cluster. When the deceased was Indigenous, living outside a capital city, or living in the northern part of Australia (in particular, Northern Territory, Queensland and Western Australia) then there was an increased likelihood of their death occurring within a suicide cluster. These findings suggest that suicide clustering might be linked with geographical and Indigenous factors, which supported sociological explanations of suicide clustering. This finding is significant for justifying resource allocation for tackling suicide clustering in particular areas.

Chagas disease in Australia and New Zealand: risks and needs for public health interventions

International migration has changed the global distribution of Chagas disease, with the emerging importance of non-endemic regions. We aimed at better documenting the Australia and New Zealand risk of Chagas disease and needs for interventions. We reviewed Chagas disease-related evidences, policies and practices in Australia and New Zealand and calculated the estimated prevalence. Australia hosts a rapidly growing population at risk and had 1928 infected residents in 2011; New Zealand had 98 in 2006. These figures underestimate the real situation, as they do not consider non-permanent residents. The only existing policy in both countries is the identification of blood donors with a history of or a risk of infection via questionnaire. There is no programme of detection and care of patients. The lifetime economic burden of disease for society is potentially very high. Chagas disease is an emerging health risk with potential high human and economic costs in Australia and New Zealand in the absence of public health attention. Implementing strategies to screen high-risk groups and prevent transmission should be considered. Moreover, migration between the Western Pacific and Chagas endemic regions and the presence of vectors means this risk applies in the whole region.

Spectral nudging sensitivity experiments in a regional climate model

In this study, the scale selective bias correction (SSBC) method described by Kanamitsu et al. (2010) is further examined by considering the full wind nudging and the vertically weighted damping coefficient. The 2001 June–July–August RSM simulation over a relatively large domain covering much of the Asian continent, the northern part of Australia, and the Indian and western Pacific oceans was the main focus. The full wind nudging shows wind fields closer to the driving global analysis. However, it leads to significantly distorted fields (e.g., temperature and geopotential height) aloft, accompanying excessive precipitation over the western Pacific. The gradual reduction of vorticity nudging from the model top to the ground surface improves rainfall patterns without a discernible distortion of large-scale fields. Further evaluation of a 10-year-summer simulation over East Asia confirmed that this revised SSBC method improves the monsoonal rainfall against the method of Kanamitsu et al. It is therefore concluded that vorticity nudging alleviates largescale errors by maintaining the near geostrophic balance between mass and winds. The reduction of this nudging factor in the lower troposphere allows the ageostrophic component of wind to develop as in nature, which leads to the improvement of precipitation.

The First Record of Scleria caricina (R. Br.) Benth. (Cyperaceae) in Korea

We report S. caricina (R. Br) Benth. (Cyperaceae) as an unrecorded species from Sinan-gun, Jeollanam Province on the Korean peninsula. This taxon was known to be distributed mainly in southeast Asia, China, Japan, and the northern part of Australia. S. caricina is distinguished from other species of the genus Scleria in Korea by having congested inflorescences, 3-toothed pistillate scales at the apex, and enclosed achenes in 2 scales. The new Korean common name, 'Ae-gi-gae-ol-mi', is given considering the small-size of the plants. A description based on the morphological characters and the illustrations of this species are provided with a taxonomic key to the species of Scleria in Korea.

Heavy rainfall caused by interactions between monsoon depression and middle-latitude systems in Australia: a case study

The heavy rainfall caused by interactions between the monsoon depression and the middle-latitude systems in Australia has been investigated in this paper. For a better understanding of the Australian monsoon depression (AMD) and its synoptic-scale interaction with the middle-latitude systems, some key meteorological parameters have been calculated, including the vorticity budget, moisture budget, temperature advection, frontogenesis function and potential vorticity. The results show that interaction between the lower and mid-latitude systems does exist leading to the merging of the extratropical low with frontal systems and the AMD, meanwhile both the low-level cold air from the mid-latitude and the warm moist air that was lifted by the front were very favorable for the formation and the intensification of heavy rainfall, which was quite different from the rainfall caused by the AMD alone. Second, the obvious temperature advection and gradient were detected, so the baroclinicity was favorable to the intensification of the front, as well as to the development of the upper-level jet. Next, isentropic analysis revealed that the south-west cold-flow sank and met the warm flow coming from the northern part of Australia, thereby forming the obvious baroclinic zone in the lower troposphere. A high-PV anomaly area located in the upper level of the troposphere, which overlaid the low-level frontogenesis zone, also existed. The upper-level PV maximum extended downwards forming a vertical PV column when the extratropical low intensified. Furthermore, the AMD is a warm-cored vortex located in middle and upper troposphere with a deep and thick moisture layer, and there were some differences in the vorticity and moisture budgets of the two different stages. Finally, based on the above-mentioned analysis, a conceptual model describing the interactions between the lower and middle-latitude systems in the southern hemisphere was proposed.

TheEucalyptuscanker pathogenChrysoporthe cubensisdiscovered in eastern Australia

Chrysoporthe cubensis is an important pathogen of commercially planted Eucalyptus species (Myrtaceae) in tropical and subtropical parts of the world where these trees are planted as non-natives. Although the majority of Eucalyptus spp. are native to Australia, Chr. cubensis is not common there and has been reported only once from naturally growing Eucalyptus marginata in Western Australia. Chr. cubensis is able to infect hosts in the Myrtaceae and Melastomataceae other than Eucalyptus, but has not been found on hosts other than Eucalyptus in Australia. Recently, fruiting structures resembling those of Chr. cubensis were discovered on Tibouchina heteromalla, planted as a non-native in the Botanical Gardens in Cairns, northern Queensland. These fruiting structures and resulting isolates were characterised as Chr. cubensis in this study. Pathogenicity studies found that Corymbia spp., including commercially important spotted gum, are susceptible along with E. pilularis and E. dunnii. The discovery of Chr. cubensis on a non-native plant in the northern part of Australia is important as it might imply that the pathogen has been introduced into the country and pose a significant threat to native Eucalyptus forests. Alternatively, this fungus might occur naturally in the area on hosts other than Tibouchina, possibly Eucalyptus or related species, and that Australia forms part of its native range.

A case of pulmonary melioidosis

Melioidosis is a rare infectious disease that is very prevalent in certain areas of the world, namely Thailand and certain parts of Northern Australia. There are only 29 cases being reported in the UK since 1988. With air transport industry getting more and more readily available and affordable, it is important to recognise this disease especially those who have recently travelled to those endemic regions. We report a case of a man who presented with pulmonary melioidosis after recent travel to Thailand.

SAAFP/PC Mini-Congress: Saturday 9 May 2009

The book describes the peculiarities of practice in a small industrial town in England (''The trials of Rosie B'') where Rosie, who was fifteen years old, denied that she was pregnant and hid her baby under the wardrobe when the doctor was called! On the other hand, in ''Eggs and Bacon in Alice Springs'', a doctor working in a remote northern part of Australia with an aboriginal community, reflects on the high prevalence of scabies, tuberculosis and otitis media in children. He bemoans the inadequate health infrastructure, describes the frustration of efforts in saving children's lives only for them to return with similar problems not long afterwards and questions his relevance in such a situation.

Nematodes of the Superfamilies Diplotriaenoidea and Physalopteroidea in the Coelomic Cavity of a Pygmy Desert Monitor (Varanus eremius)

The pygmy desert monitor (Varanus eremius) is a small lizard that is found across the northern part of Australia. These timid lizards primarily prey on small lizards, scorpions, and large insects. As a carnivore, it is possible that these animals are exposed to a variety of parasites. Larval stages of the physa- lopterid nematode Abbreviata tumidocapitis were found encysted in various tissues and were free in the coelomic cavity of a wild-caught pygmy desert monitor. In addition, three adult Hastospiculum gouldi were recovered from the coelomic cavity. This is the first time that Abbreviata tumidocapitis and Hastospiculum gouldi have been found in this species of monitor. KEY W ORDS: Abbreviata tumidocapitis, cyst, Hastospiculum gouldi, nematode, pygmy desert monitor, Varanus eremius.

Clothing and Climate in Aboriginal Australia

Ethnohistorical study of the use of clothing among Australian Aborigines in relation to their thermal environment indicates that clothing was a behavioral adaptation to cold exposure. Seasonal data and trends in Tasmania and parts of northern Australia are not entirely consistent with the overall thermal pattern. Likely reasons for these anomalies include interaction between latitude and season of observation, greater biological adaptation to cold south of Bass Strait, and influence from a regional cultural sphere centered north of the mainland.

The short-term effects of an extensive and high-intensity fire on vertebrates in the tropical savannas of the central Kimberley, northern Australia

We report the effects of an extensive (&gt;7000 km2), high-intensity late-dry-season fire in the central Kimberley, Western Australia, on the species richness and abundance of mammals, reptiles and birds. Five weeks after the fire we surveyed 12 sites (six burnt, six unburnt); each pair of sites was closely matched for soil type and vegetation. The species richness and abundance of mammals and reptiles was greater at unburnt sites, especially for mammals (with a 4-fold difference in abundance between burnt and unburnt sites). There was an indication that reptiles immigrated into unburnt patches, but mammals did not. There were also species-specific responses to the fire: Rattus tunneyi and Pseudomys nanus were much more abundant in unburnt sites, whereas Pseudomys delicatulus was caught in equal numbers at burnt and unburnt sites. Diurnal reptiles were more abundant at unburnt sites, but nocturnal reptiles were equally common at burnt and unburnt sites. Avian species richness and overall abundance was similar between burnt and unburnt patches, although a few species showed preferences for one state or the other. The overall high trapping success for mammals (18% across all sites; 28% in unburnt patches) contrasts with the well documented mammal collapse in parts of northern Australia and seems paradoxical given that our study area has experienced the same increase in fire frequency and extent that is often blamed for species collapse. However, our study area has fewer pressures from other sources, including grazing by large herbivores, suggesting that the effects of these pressures, and their interaction with fire, may have been underestimated in previous studies.

Vulnerability model of an Australian high-set house subjected to cyclonic wind loading

This paper assesses the damage to high-set rectangular-plan houses with low-pitch gable roofs (built in the 1960 and 70s in the northern parts of Australia) to wind speeds experienced in tropical cyclones. The study estimates the likely failure mode and percentage of failure for a representative proportion of houses with increasing wind speed. Structural reliability concepts are used to determine the levels of damage. The wind load and the component connection strengths are treated as random variables with log-normal distributions. These variables are derived from experiments, structural analysis, damage investigations and experience. This study also incorporates progressive failures and considers the inter-dependency between the structural components in the house, when estimating the types and percentages of the overall failures in the population of these houses. The progressively increasing percentage of houses being subjected to high internal pressures resulting from damage to the envelope is considered. Results from this study also compare favourably with levels of damage and related modes of failure for high-set houses observed in post-cyclone damage surveys.

A revision of the marine eel-tailed catfish genus 'Euristhmus' (Teleostei: Siluriformes: Plotosidae)

The Indo-west Pacific plotosid catfish genus Euristhmus Ogilby is revised and found to include five species: E. lepturus (G nther) occurs along the eastern and northern parts of Australia, from Sydney to the Gulf of Carpentaria; E. microceps (Richardson) is reported from Shark Bay, Western Australia to Goulburn Islands, Northern Territory; and E. nudiceps (G nther), the most widely distributed species, extends along the northern margin of Australia, from Exmouth Bay, Western Australia to Moreton Bay, Queensland. Two new species are described herein: E. microphthalmus, from coastal regions of the Northern Territory, Australia and West Papua, Indonesia; and E. sandrae from the vicinity of Rowley Shoals and Exmouth Gulf, Western Australia. Exilichthys Whitley is a junior synonym of Euristhmus; Cnidoglanis microcephalus G nther is an unnecessary replacement name for E. microceps; and Plotosus elongatus Castelnau is a junior subjective synonym of E. lepturus. A lectotype is designated for Cnidoglanis lepturus G nther.

Knoelle, a new monotypic wolf spider genus from Australia (Araneae: Lycosidae)

A new monotypic wolf spider genus, Knoelle, is described to accommodate the Australian member of the Lycosinae Knoelle clara (L. Koch, 1877) comb. nov. as type species. Knoelle gen. nov. differs from all other wolf spiders in the peculiar structure of the male pedipalp. The tip of the cymbium carries a unique, large patch of macrosetae and the tegular apophysis has a unique lamellar structure between two hook-shaped processes. The median septum of the female epigyne widens distinctly anteriorly. Knoelle clara comb. nov. is common in the northern parts of Australia (New South Wales, Northern Territory, Queensland, Western Australia) north of ca. 30°S latitude. The species appears to prefer sandy, open to partly shaded habitats near freshwater, such as creeks, springs and lakes, but can also be found in sand dunes near beaches. Adults show a peak of activity in October (males) and November (females) and records of mature spiders are rare between May and August.

Predicting sheetwash and rill erosion over the Australian continent

Soil erosion is a major environmental issue in Australia. It reduces land productivity and has off-site effects of decreased water quality. Broad-scale spatially distributed soil erosion estimation is essential for prioritising erosion control programs and as a component of broader assessments of natural resource condition. This paper describes spatial modelling methods and results that predict sheetwash and rill erosion over the Australian continent using the revised universal soil loss equation (RUSLE) and spatial data layers for each of the contributing environmental factors. The RUSLE has been used before in this way but here we advance the quality of estimation. We use time series of remote sensing imagery and daily rainfall to incorporate the effects of seasonally varying cover and rainfall intensity, and use new digital maps of soil and terrain properties. The results are compared with a compilation of Australian erosion plot data, revealing an acceptable consistency between predictions and observations. The modelling results show that: (1) the northern part of Australia has greater erosion potential than the south; (2) erosion potential differs significantly between summer and winter; (3) the average erosion rate is 4.1 t/ha.year over the continent and about 2.9 × 109 tonnes of soil is moved annually which represents 3.9% of global soil erosion from 5% of world land area; and (4) the erosion rate has increased from 4 to 33 times on average for agricultural lands compared with most natural vegetated lands.

Melioidosis

Melioidosis is an infection with the gram-negative bacillus Burkholdria pseudomallei, previous known as Pseudomonas pseudomallei. We present a case report of a man with Non-Hodgkin's Lymphoma, who after visiting Indonesia presented himself with a urosepsis, with positive cultures to B. pseudomallei. Melioidosis is endemic in areas of southeast Asia and the northern part of Australia. Infection with the B. pseudomallei has a high mortality rate. Diagnosis can be made on the basis of cultures, the bacteria grow on standard media. Treatment should be based up on sensitivity studies. The optimum duration of therapy and choice of antibiotics remain to be determined. Due to the increase in travel, the infection will be seen more frequently in other parts of the world.