Tropical North Australia Research Articles

A possible remote tropical forcing for the interannual variability of peak summer muggy hot days in Northeast China

The peak summer (July–August; JA) muggy hot weather over Northeast China (NEC) negatively impacts local socioeconomic development and human health. This study investigates the physical connection between sea surface temperature (SST) and year-to-year variations in the number of peak summer muggy hot days (MHDs) in NEC (PSMHDNEC) for the period 1979–2018. We found that on the interannual timescale, SST anomalies (SSTAs) over the tropical North Australia (TNA) sector have a stable and significant negative correlation with PSMHDNEC since the early summer of June; however, the strongest negative correlation occurs in the JA. Our further analyses indicate that the SST cooling over the TNA sector could form a large-scale atmospheric teleconnection emanating northwest of the TNA through the profound in situ diabatic cooling anomalies tied to the SST cooling, which propagates poleward from the northeastern Pacific Ocean. This teleconnection might remotely strengthen the local-scale anticyclonic anomaly centered near NEC, a critical system responsible for a higher PSMHDNEC. Under such circumstances, the NEC region is dominated by high-pressure anomalies, facilitating the establishment of localized MHD-favorable environmental conditions (e.g., increased surface air temperature and enhanced downward solar radiation flux with suppressed convection activities). During years of negative SSTAs over TNA, local SSTAs can persist from early summer until JA via the wind–evaporation–SST feedback. Therefore, it appears that SSTAs over the TNA sector may be a significant remote tropical forcing factor for the interannual variability of PSMHDNEC, and the corresponding June SST cooling may act as a potential predictability source physically contributing to a higher PSMHDNEC.

Epidemiological analysis of association between lagged meteorological variables and pneumonia in wet-dry tropical North Australia, 2006-2016.

Pneumonia accounts for 1.5% of all overnight hospital admission in Australia. We investigated the nonlinear and delay effect of weather (temperature and rainfall) on pneumonia. This study was based on a large cohort of inpatients that were hospitalized due to pneumonia between 2006 and 2016. Cases were identified using the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD10-AM) codes J10.0*-J18.0*. A time-varying distributed lag nonlinear model was used to estimate the burden of the disease attributable to varying weather-lag pneumonia relationships and identify vulnerable groups. The relative risk (presented as logRR) associated with temperature was immediate and highest in late winter at the lowest temperature of 16 °C (logRR = 1.13, 95% confidence intervals (CI): 0.59, 1.66). The cumulative effect over the lag range 0-8 weeks revealed two peaks for low (12 mm, logRR = 0.73, 95% CI: 0.32, 1.13) and moderately high rainfall (51 mm) with logRR of 1.15 (95% CI: 0.10, 2.20). A substantial number, 22.50% (95% empirical CI: 1.83, 34.68), of pneumonia cases were attributable to temperature (mostly due to moderate low temperatures). Females and indigenous (Aboriginal and Torres Strait Islander) patients were particularly vulnerable to the impact of temperature-related pneumonia. In this study, we highlighted the delayed effects and magnitude of burden of pneumonia that is associated with low temperature and rainfall. The findings in this study can inform a better understanding of the health implications and burden associated with pneumonia to support discussion-making in healthcare and establish a strategy for prevention and control of the disease among vulnerable groups.

Circling the Cyclone: Children’s Understanding of Natural Disasters through the Arts

Natural disasters can occur unexpectedly with devastating effects as attested by recorded history documents. They have caused immense suffering and destruction. In recent years, natural disasters have increased due to climate change. Further, the need for public awareness of catastrophic events has also increased, along with the media push to prepare for these events. Disaster preparedness has reduced loss of life and property, and children have demonstrated that they have the capacity to be actively involved in disseminating important and useful disaster information and the ability to assist with disaster preparedness in their families. Therefore, disaster preparedness is now an established part of the school curricula. However, while the topic of natural disasters is increasingly being included in school curricula, teachers may still feel uneasy introducing students to this topic. If they have not experienced a natural disaster and are not aware of the severity of disasters, teachers may lack the necessary information to best educate and support children. Further, teachers may need to tread a fine line between transmitting facts and shocking students with the emotive results of disasters. This is further exacerbated by media reporting. Arising from a document study of children's drawings from the 2006 Cyclone Larry natural disaster in tropical north Queensland, Australia, and research into cyclones, this paper presents strategies, including a poem, for teachers to introduce natural disasters to students in the upper primary school years. It may help to facilitate understanding about natural disasters and preparedness for these occurrences.

Asian Servants for the Imperial Telegraph: Imagining North Australia as an Indian Ocean Colony before 1914

In the late nineteenth century, the officers of the Eastern Extension Australasia and China Telegraph Company provided north Australia with a cable connection to London via Java, Singapore, and India. The telegraph project prompted a new era of colonisation in tropical north Australia and the officers of the company sought to ensure that the north would be shaped according to their notions of Indian Ocean colonial culture. They insisted on employing Asian domestic servants in opposition to White Australian nationalists who advocated restrictions on Asian migration. Like the pearling industry, which was permitted ongoing access to Asian labour, the telegraph company drew on the support of liberal parliamentarians, and leveraged their privileged position as providers of imperial telecommunications to develop an elite colonial counter-culture in north Australia.

Putting Carmona’s Place-shaping Continuum to use in research practice

This paper critically considers Carmona’s Place-shaping Continuum in the context of Cairns in tropical north Australia to explore the model’s applicability across different cultures and contexts. Drawing from context analysis and interviews with knowing and unknowing urban designers, this research uses a critical policy lens to consider how the process of designing the city for use might apply in Cairns, a regional, tropical city quite different from where Carmona’s model of urban design was developed from. Results indicate that in Cairns, the geopolitical, economic, environmental and cultural contexts continue to influence how things are done in the city; there is little to distinguish knowing and unknowing urban designers from one another; and that whilst urban designers consider themselves to have a role in the urban design process, few assume ownership of the process. The paper concludes that Carmona’s context elements of place, polity and power are fundamentally important in the application of the model in research practice.

Ampithoidae and Maeridae amphipods from Timor-Leste (Crustacea: Peracarida)

Five known and four new species of amphipod are documented from Timor-Leste. The species biodiversity of the region shows a close affinity to what is known from tropical north Australia. Although records of amphipods from the Lesser Sunda Region are limited, the species recorded have distributions throughout the broader Indo-Pacific. The new species Ampithoe atauro, Elasmopus tibarensis, Linguimaera christorei and Quadrimaera metinaro are described herein.

제주도 내 난과(Orchidaceae) 보춘화속(Cymbidium)식물의 분포 및 자생지의 식생 구조

본 연구는 난과 희귀식물인 보춘화속의 제주도 분포범위와 자생지의 식생구조를 파악하기 위하여 실시되었다. 보춘화속은 전 세계적으로 아시아 및 호주 북부의 열대 및 아열대 지역에 분포하고 있다. 국내에서는 한란, 소란, 대흥란, 죽백란, 녹화죽백란, 보춘화 등 총 6종이 분포하고 있으며, 이들 6종은 모두 제주도에 분포하고 있다. 제주도 내 보춘화속은 해발 16-547m 사이에 분포하였는데, 이 중 대흥란은 해발 16-547m 사이에 분포하여 가장 넓은 해발 분포 범위를 나타냈다. 반면에 죽백란, 녹화죽백란, 소란 등은 한라산 남사면의 돈내코 계곡 및 효돈천계곡 등 좁은 해발 분포 범위를 나타냈다. 이들 종은 열대 및 아열대 지역에 분포하는 종으로서 기후온난화가 진행될 경우 제주도내에서의 해발 분포 범위 확대와 한반도 내륙으로의 자생지 확산이 예측된다. 한편, 제주도내에서 보춘화속자생지의 식생구조를 분석한 결과, 구실잣밤나무 군락과 구실잣밤나무-곰솔 군락, 곰솔-상수리나무 군락, 곰솔군락, 종가시나무-푸조나무 군락 등 5개 군락으로 구분되었다. 이들 군락내에서 자라는 보춘화속 중 한란과 소란 및 죽백란 등 3종은 구실잣밤나무 군락에서만 출현하였으며, 녹화죽백란은 구실잣밤나무-곰솔 군락에서 출현하였고, 대흥란은 곰솔-상수리나무 군락과 곰락 군락 및 종가시나무-푸조나무 군락 등 3개 군락에 분포하였다. 반면 보춘화는 구실잣밤나무-곰솔 군락, 곰솔-상수리나무 군락에서 출현하였다. 제주도에 분포하는 보춘화속은 불법 채취에 의해 개체수가 급격히 감소하고 있으며, 특히 한란, 죽백란, 녹화죽백란, 소란등은 식생학적으로 분포 범위가 매우 협소한 것으로 판단되며 이들 종에 대한 보전방안 마련이 필요할 것으로 사료된다. This study was carried out to investigate the range of distribution and vegetation structure of habitats of genus Cymbidium which is distributed in Jeju Island, Korea. This genus is distributed in tropical and subtropical Asia and North Australia. In Korea, there are six species [i. e. C. goeringii (Rchb. f.) Rchb. f., C. kanran Makino, C. lancifolium Blume var. aspdistrifolium (Fukuy.) S. S. Ying., C. macrorhizum Lindl., C. nagifolium Masam. and C. ensifolium L.], which were also distributed in Jeju Island. The habitats of this genus ranged between 16 meter and 574 meter above sea level in Jeju Island. C. macrorhizum had the broadest altitudinal range (16-574 meter above sea level), whereas C. ensifolium, C. nagifolium and C. lancifolium var. aspidistrifolium had the narrow altitudinal range. According to the classification analysis by TWINSPAN, the plant communities were divided into five groups of Castanopsis sieboldii community, Castanopsis sieboldii-Pinus thunbergii community, Pinus thunbergii-Quercus acutissima community, Pinus thunbergii community and Quercus glauca- Aphananthe aspera community. Three species, C. kanran, C. nagifolium, and C. ensifolium inhabited Castanopsis sieboldii community and C. lancifolium var. aspdistrifolium inhabited Castanopsis sieboldii-Pinus thunbergii community. C. macrorhizum inhabited Pinus thunbergii community, Pinus thunbergii-Quercus acutissima community and Quercus glauca-Aphananthe aspera community. C. goeringii inhabitated Castanopsis sieboldii-Pinus thunbergii community and Pinus thunbergii-Quercus acutissima community. The populations of the genus Cymbidium have been extremely decreased due to illegal collection in Jeju Island. Especially, the distribution range of C. kanran, C. nagifolium, and C. ensifolium was narrow and limited to evergreen broad-leaved forests, therefore, conservation plans are needed for the protection of these species.

Effect of temperature and salinity on egg hatching and description of the life cycle of Lernanthropus latis (Copepoda: Lernanthropidae) infecting barramundi, Lates calcarifer

The parasite Lernanthropus latis (Copepoda: Lernanthropidae) is a major threat to the sustained mariculture of barramundi, Lates calcarifer (Perciformes: Latidae). We investigated the effect of water temperature and salinity on egg hatching success of L. latis and describe the life cycle for the first time. Wild and sea-caged L. calcarifer examined in tropical north Australia exhibited similar parasite prevalence (range: 80–100%) and mean parasite intensity (range: 3–6), whereas land-based maricultured fish were not infected. Hatching success and time to first and last hatch was determined for a range of water temperature (22, 30, 32 and 34°C) and salinity (0, 11, 22, 35 and 40‰) combinations representing current and predicted climate conditions. There was a significant interaction between water temperature and salinity on the hatching success of L. latis nauplii. Eggs hatched in all temperature treatments, with the greatest hatching success at 30°C and 32°C (98 and 92% success, respectively) in 35‰. Hatching did not occur at 0‰ and was severely reduced at 11‰ (1.6% success). Hatching began within 6h at all water temperatures with >95% of eggs hatched within 30h at 30, 32 and 34°C and within 60h at 22°C. Adult parasites differed from the original description by the presence of the parabasal flagellum, small setae on the legs and caudal rami and minor incongruences regarding morphological measurements. The life cycle of L. latis includes three free living stages and five parasitic stages. Although L. latis exhibits broad environmental tolerance, freshwater can be used as an effective management strategy to break the life cycle in aquaculture.

Wetland conservation and sustainable use under global change: a tropical Australian case study using magpie geese

Imminent shifts in environmental parameters due to climatic change might have profound ramifications for wetlands listed under the Ramsar convention. Although the exact mechanisms by which global change will affect these systems are not known, models that simulate component drivers, particularly at a broad spatial scale, can nevertheless allow for more informed conservation decision making. Such general inference is particularly needed for wetlands across the tropics, where less knowledge and fewer resources are available to mitigate the impacts on important conservation sites. Here we develop a case study of wetland loss to sea level rise across tropical north Australia (including Ramsar‐listed sites), and link these to a metapopulation model for a keystone endemic waterbird, the magpie goose Anseranas semipalmata. We projected published models on sea level rise through to the year 2400, and found a non‐linear trajectory of inundation up to 20 m above present levels. Digital elevation models were used to simulate sea level rise and the spatially differentiated loss of wetland habitat used by geese. Range retraction was linked to decline in ecological carrying capacity, and we coupled wetland‐specific habitat loss projections to a spatially explicit demographic metapopulation model. Additionally, we included alternate harvest strategies based on present‐day estimates of indigenous and non‐indigenous offtake of geese, and examined the synergy between wetland loss and hunting on extinction risk. Our results suggest that Australia's once‐abundant and widespread magpie goose will be reduced to a fragmented population of just a few thousand individuals within the next 200–300 yr. Harvest could continue for some time, up to a “tipping point” at around 5% loss of current wetland habitat, after which the decline of geese is rapid. Given the inexorable nature of sea level rise, short‐ to medium‐term conservation of waterbirds across Ramsar wetlands must prepare for adaptive wetland management, such as through buffer‐placement, and ongoing monitoring of harvest.

A Satellite Analysis of Contrasting Fire Patterns in Aboriginal- and Euro-Australian Lands in Tropical North Australia

We use satellite imagery to compare and contrast fire patterns across a repeating mosaic of vegetation types occurring within the tropical savanna of the Northern Territory, Australia. Our study area included different land management settings that encapsulate three contrasting styles of management that have developed following European settlement in northern Australia: The lowland eucalypt savannas were the most burnt of any vegetation type, but within eucalypt savannas there were subtle differences in fire frequency. The highest fire frequencies were recorded in national park and military lands, intermediate frequencies on Aboriginal lands, and the lowest fire frequencies on pastoral properties. Aboriginal lands had an even distribution of fire throughout the dry season in contrast to the marked bias towards early dry season landscape burning on all Euro-Australian controlled lands. These findings illustrate the impact of different management paradigms and cultural decisions about fire on physical fire patterns.

The Jellyfish hunter—Jack Barnes: A pioneer medical toxinologist in Australia

Dr Jack Handyside Barnes (1922–1985) was one of the small and elite group of Pacific marine toxinologists whose work was characterised by an uncompromising rugged persona, a focussed resolve to solve challenging problems of human clinical envenomation, and who conducted curiosity-driven research under conditions of scientific isolation. He was a pioneering advocate for the preservation of marine heritage, particularly that of the Great Barrier Reef. A former military commando who later became a general medical practitioner with extensive surgical and obstetric skills, in 1947 he was appointed the Medical Superintendent of Thursday Island in the Torres Strait. Later (from January 1953), he worked indefatigably as a general medical practitioner in Cairns, in tropical North Australia. For four decades (1945–1985), Jack Barnes undertook detailed laboratory, clinical and field research into invertebrate envenomation, particularly medusan toxinology. In 1960 he discovered the species responsible for the Irukandji syndrome, a small carybdeid named Carukia barnesi in his honour. He invented the research technique for the extraction of venom from the world's most venomous creature, the Pacific box Jellyfish, Chironex fleckeri. By 1960, he had published taxonomic details of nematocyst structure and clinical envenomation details consequent upon stings by Physalia, Cyanea, Chironex, Chiropsalmus and Carukia. This paper is a précis of the chronology of his life, contributions and influence.

Conservation genetics of Lumnitzera littorea (Combretaceae), an endangered mangrove, from the Indo-West Pacific

Mangrove forests, with their ecological significance and economic benefits, are vital inter-tidal wetland ecosystems. Lumnitzera littorea (Combreataceae) is a non-viviparous mangrove distributed in tropical Asia and North Australia. Due to natural and human impacts, populations of this species have been isolated, fragmented, and highly disturbed. In China, L. littorea is an endangered species, restricted to small regions of Hainan Island. The genetic composition of five populations of this species from the Indo-West Pacific (South China, Malay Peninsula, Sri Lanka, North Australia) was assessed using inter simple sequence repeat (ISSR) makers. At the species level, expected mean heterozygosity (He) was 0.240 with 75.6% of loci polymorphic (P). However, genetic variation was much lower at the population level (P = 37.1%, He = 0.118). A high coefficient of gene differentiation (Gst = 0.515) and low level of gene flow (Nm = 0.470) indicated significant genetic differentiation among populations. AMOVA also indicated that more than half the total variation (58.4%) was partitioned among populations. The high degree of differentiation observed among populations emphasizes the need for appropriate conservation measures that incorporate additional populations into protected areas, and achieve the restoration of separate, degraded populations.

Historical biogeography of Australian Rhamnaceae, tribe Pomaderreae

AbstractAim To discover the pattern of relationships of areas of endemism for Australian genera in the plant family Rhamnaceae tribe Pomaderreae for comparison with other taxa and interpretation of biogeographical history.Location Australian mainland, Tasmania and New Zealand.Methods A molecular phylogeny and geographic distribution of species within four clades of Pomaderreae are used as a basis for recognition of areas of endemism and analysis of area relationships using paralogy‐free subtrees. The taxon phylogeny is the strict consensus tree from a parsimony analysis of 54 taxa, in four clades, and sequence data for the internal transcribed spacer regions of ribosomal DNA (ITS1‐5.8S‐ITS2) and the plastid DNA region trnL‐F.Results The biogeographical analysis identified five subtrees, which, after parsimony analysis, resulted in a minimal tree with 100% consistency and seven resolved nodes. Three sets of area relationships were identified: the areas of Arnhem and Kimberley in tropical north Australia are related based on the phylogeny of taxa within Cryptandra; the moister South‐west of Western Australia, its sister area the coastal Geraldton Sandplains, the semi‐arid Interzone region and arid Western Desert are related, based on taxa within Cryptandra, Spyridium, Trymalium and Pomaderris; and the eastern regions of Queensland, McPherson‐Macleay, south‐eastern New South Wales (NSW), Victoria, southern Australia, Tasmania and New Zealand are related based on Cryptandra, Pomaderris and Spyridium. Tasmania and NSW are related based entirely on Cryptandra, but the position of New Zealand relative to the other south‐eastern Australian regions is unresolved.Main conclusions The method of paralogy‐free subtrees identified a general pattern of geographic area relationships based on Australian Pomaderreae. The widespread distribution of clades, the high level of endemicity and the age of fossils for the family, suggest that the Pomaderreae are an old group among the Australian flora. Their biogeographical history may date to the early Palaeogene with subsequent changes through to the Pleistocene.

Sustainable development in the indigenous-owned savanna: innovative institutional design for cooperative wildlife management

This study examines a particular form of cooperative wildlife management on Aboriginal land in the tropical savanna of the Northern Territory of Australia, in the context of broader questions about governance. It asks how governance at the local or community level can be designed to ensure sustainable development and real economic benefit for the region’s long-term indigenous residents. It is argued here that sustainable development will require hybrid institutions that accommodate and value the principles and practices of indigenous resource management, while also recognising the benefits of broader regional resource governance. Emerging best practice in wildlife harvesting that is founded on careful scientific assessments of sustainability is identified, and an approach to northern development based on sustainability and locally controlled commercialisation is canvassed. Future challenges to the proposed approach include convincing governments and state agencies of its national as well as regional benefits. Reform of governance to facilitate its rapid implementation is desirable, in the context of the relative poverty currently experienced by many indigenous people in tropical north Australia.

Spatial variation in the duration of the rainy season in monsoonal Australia

AbstractClimatological research in the tropics of northern Australia has focused particularly on the Australian summer monsoon. However, the timing of many ecologically important processes is determined not by the monsoon but by extra‐monsoonal rainfall events. These events produce a temporal pattern of wet and dry spells that is at least as important ecologically as the amount of rain. We defined the rainy season as that period when the probability of 10‐day dry spells was less than 0.5, and the wet season as that period within the rainy season when the probability of dry spells was less than 0.1. We applied these criteria to seven stations along a strong north–south rainfall gradient spanning more than 12° of latitude in tropical north Australia. The duration of the rainy and wet seasons in northern Australia decreases with increasing latitude. The timing and duration of these seasons were also affected by the El Niño–Southern Oscillation (ENSO). The relative contribution of temporally isolated rainfall events to both the duration of the rainy season and the amount of rainfall increases with latitude. The geographic variation in these seasons corresponds to many patterns occurring in natural ecosystems. We argue that understanding the extra‐monsoon rainfall events is critical to understanding how climate variation affects natural ecosystems. Copyright © 2001 Royal Meteorological Society

Cupule engravings from Jinmium–Granilpi (northern Australia) and beyond: exploration of a widespread and enigmatic class of rock markings

Antiquity last year reported a startlingly old series of dates from Jinmium in tropical north Australia. At Jinmium are old rock-engravings, the pecked cups or cupules that are widespread in Australia. This study of the Jinmium cupules goes beyond that immediate topic to broader issues.

The Competition Effect of Brachiaria decumbens on the Early Growth of Direct-Seeded Trees of Alphitonia petriei in Tropical North Australia

The Competition Effect of Brachiaria decumbens on the Early Growth of Direct-Seeded Trees of Alphitonia petriei in Tropical North Australia

Survival and Growth Responses of a Number of Australian Tree Species Planted on a Saline Site in Tropical North Australia

The survival and growth of 15 species and provenances of Australian trees planted on a saline site in dry tropical northern Australia was examined. The study site was divided between high, moderate and low salinity subsites. A randomized complete block design was used for each subsite. 2. Tree survival and height were measured at 3 and 24 months. Measurements of diameter at breast height, tree crown size, branch number per tree, growth form, fork numbers per tree, and leaf length, width and thickness were conducted at 24 months. Soil salinity was measured at 3, 12 and 24 months. These data were statistically analysed to examine the effect of salinity on tree survival and growth and the differences in response between taxa. 3. The survival and growth varied with salinity and species. Trees grown on the high salinity subsite had the lowest survival and poorest growth rate. Casuarina cunninghamiana, C. glauca and Eucalyptus camaldulensis achieved the highest survival, fastest growth rate and best growth form. Acacia aulacocarpa showed the poorest performance. 4. It is suggested that species selection for utilization of saline sites should be made according to salinity, species salt tolerance and management objectives. Plant height and diameter, crown size and branch number are important characteristics which indicate salt tolerance. Those species with an ability to maintain a relatively large crown and a high number of branches when subjected to salinity are most likely to be highly tolerant to salt.

Salinity effects on tree growth, root distribution and transpiration of Casuarina cunninghamiana and Eucalyptus camaldulensis planted on a saline site in tropical north Australia

A study was carried out to compare tree response to soil salinity of Casuarina cunninghamiana and Eucalyptus camaldulensis grown on a saline site in tropical north Australia. The site was divided into low- (< 0.6 dS m −1), moderate- (0.6–1.1 dS m −1) and high- (> 1.1 dS m −1) salinity subsites on which seedlings were planted in a randomised complete block design. Tree response was examined with regard to survival, height, DBH (diameter at breast (1.4 m) height), root growth, transpiration rate and plant chemical components at ages 24–36 months. Both species had a similarly high survival rate. Compared with C. cunninghamiana, E. camaldulensis trees were taller with greater DBH at both low and moderate salinity, and transpired more water in both summer and winter. C. cunninghamiana possessed a shallow root system with the bulk of the lateral roots in the upper 12 cm of soil, while E. camaldulensis had a deep root system with the majority of the lateral roots located in the upper 28 cm. C. cunninghamiana appeared to use less water than E. camaldulensis in both summer and winter. It is suggested that although both C. cunninghamiana and E. camaldulensis were salt-tolerant, E. camaldulensis is preferable for reclamation of salt-affected land, particularly when the salinity is moderate or low.

A case study of shelterbelt effect on potato (Solanum tuberosum) yield on the Atherton Tablelands in tropical north Australia

An experimental study was conducted on the Atherton Tablelands of tropical north Australia to quantify the shelterbelt benefit to the production of potato (Solanum tuberosum). Wind speed, wind direction and potato yield were measured at various distances from the leeward side of the shelterbelt. Non-linear modelling was used to describe the relationship between potato yield and distance from the shelterbelt. With the developed model, definite integral was used to calculate the net increase percentage of potato yield.