COVID-19 Advice for the JCU Community - Last updated: 20 October 2021, 8am (AEST)

College of Science and Engineering CSE publications Recent publications in Earth and Environmental Sciences

Apply now

Recent publications in Earth and Environmental Sciences

Munksgaard, Niels C., and Nelson, Paul N. (2021) Coupled polymer-membrane equilibration and cavity ring-down spectrometry for the highly sensitive determination of dissolved methane in environmental waters. Analytical Letters. (In Press)
High sensitivity field-based analysis of dissolved methane in surface water and groundwater is needed to monitor the environmental impacts of natural gas-field development and understand microbial carbon cycling in water bodies. A new analytical technique using a polymer membrane contactor coupled to a laser-based cavity ringdown spectrometer was developed and tested. By recirculating a water sample for approximately 10 mins, equilibrium was established between dissolved methane in the sample and methane in the measured gas phase according to Henry’s Law. The performance of the system was investigated by replicate analyses of several different water samples, spike recovery tests, comparison to analysis by headspace gas chromatography, and consideration of memory effects. The technique provided an adequate detection limit for the determination of natural background concentrations of methane in environmental waters and was approximately 28 times more sensitive than analysis by gas chromatography. The system is field-capable, simple to operate and calibrate, and takes advantage of the low-drift characteristics of the cavity ring-down spectrometer.

Sims, Kearrin, and Roy, Sajal (2021) Climate change mitigation and adaptation in Bangladesh: the need for community-based approaches. Asia-Pacific Viewpoint. (In Press)
Climate change is a leading threat to sustainable socio-economic development in Bangladesh. Adverse impacts of climatic disasters including flash floods, recurrent cyclones and erratic rainfall patterns are already causing hardship for both rural and urban people and are expected to accelerate into the future. The aim of this research note is to identify the core contributing economic sectors to climate change in Bangladesh, and to consider effective mitigation strategies. Following the 5th Assessment Report (AR5) of the Intergovern- mental Panel on Climate Change (IPCC) report (2014), in this paper, we argue that comprehensive mitigation measures are required in the energy, transport, buildings, industry and land-use sectors to reduce Greenhouse Gas (GHG) emissions. Our findings indicate that it is crucial that government and non-government mitigation efforts engage with community knowledge practices in order to most effectively reduce GHG emissions and combat the adverse impacts of climate change.

Law, Lisa, Azzali, Simona, and Conejos, Sheila (2021) Planning for the temporary: temporary urbanism and public space in a time of COVID-19. Town Planning Review, 92 (1). pp. 65-74.
It is a cliché to say we live in strange times: COVID-19 has focused our attention on schedules of lockdowns and long-term economic effects, and has even slowed down our experience of time due to increased cognitive loads. But as planners or urban designers it is our urban places that have also become strange: COVID-19 is altering our use of, and behaviour in, public space – from physical and social distancing to staying at home or even leaving the city altogether. We are concerned with how long we will tolerate state encroachments in public space, especially new techniques of surveillance and control, but we also see local governments opening up streets to give more public spaces back to pedestrians. In this Viewpoint we explore these paradoxes of public space in a time of COVID-19, from its temporary disappearance to the potential for temporary changes to underpin lasting strategies for liveable, economically viable and resilient public space. Although some link temporary urbanism to neo-liberal urban development and austerity policies (Stevens et al., 2019), we ponder how the COVID-19 moment critiques the status quo by providing new openings for shifting temporary urbanism into the mainstream planning toolkit. Does COVID-19 present an opportunity to make temporariness more deliberate and programmatic,thereby catalysing long-term change?

Sims, Kearrin (2021) Risk navigation for Thinking and Working Politically: the work and disappearance of Sombath Somphone. Development Policy Review. (In Press)
Motivation: On December 15, 2012 Sombath Somphone was abducted at a police checkpoint in his home city of Vientiane, the capital of Laos. This article considers his work and enforced disappearance through the lens of Thinking and Working Politically (TWP) approaches to development. The article is supportive of TWP, but emphasizes the significant risks of politicized programming in authoritarian contexts. Purpose: By examining Sombath Somphone’s work and enforced disappearance, the article seeks to produce insights for safer, and more effective, TWP programming. It considers how specific events in authoritarian contexts can suddenly re‐cast development workers and/or organizations as political dissidents. Approaches and Methods: The argument draws on analysis of grey literature; conversational and observational knowledge accrued during 18 months of fieldwork in Laos between 2011 and 2018; on‐going formal and informal interviewing with members of Laos’ civil society sector; and extensive dialogue with Sombath Somphone’s wife, Ng Shui Meng. Findings: The article identifies four key factors that contributed to the enforced disappearance of Sombath Somphone: international exposure; timing; particular elites; and strategies of oppression. It finds that there is a need for further consideration of how the dangers of politically oriented development work may be anticipated and mitigated, as well as the different forms of risk experienced by local and international development actors working within authoritarian contexts. Policy Implications: Thinking and Working Politically has much to offer to development practice, but its contributions should not threaten the safety of local development actors. More attention must be given to risk prevention and mitigation.

MacKeracher, Tracy, Mizrahi, Me'ira, Bergseth, Brock, Chit Maung, Khin May, Khine, Zin Lin, Phyu, Ei Thal, Simpfendorfer, Colin A., and Diedrich, Amy (2021) Understanding non-compliance in small-scale fisheries: shark fishing in Myanmar's Myeik Archipelago. Ambio, 50. pp. 572-585.
Achieving fisheries compliance is challenging in contexts where enforcement capacity is limited and the incentives for rule-breaking are strong. This challenge is exemplified in Myanmar, where an active shark fishery exists despite a nationwide ban on targeted shark fishing. We used the Kipling method (5W1H) to gather a complete story of non-compliance in five small-scale fishing communities in the Myeik Archipelago. Among 144 fishers surveyed, 49% were aware of the nationwide ban. Shark fishers (24%) tended to be younger individuals who did not own a boat and perceived shark fishing to be prevalent. Compliant fishers were motivated by a fear of sharks and lack of capacity (equipment, knowledge), whereas food and income were cited as key motivations for non-compliance. The results of our study emphasize that in resource-dependent communities, improving compliance for effective shark conservation may require addressing broader issues of poverty, food security and the lack of alternatives.

Thiault, Lauric, Curnock, Matthew I., Gurney, Georgina G., Heron, Scott F., Marshall, Nadine A., Bohensky, Erin, Nakamura, Nao, Pert, Petina L., and Claudet, Joachim (2021) Convergence of stakeholders' environmental threat perceptions following mass coral bleaching of the Great Barrier Reef. Conservation Biology, 35 (2). pp. 598-609.
Managing human use of ecosystems in an era of rapid environmental change requires an understanding of diverse stakeholders' behaviors and perceptions to enable effective prioritization of actions to mitigate multiple threats. Specifically, research examining how threat perceptions are shared or diverge among stakeholder groups and how these can evolve through time is increasingly important. We investigated environmental threat perceptions related to Australia's Great Barrier Reef and explored their associations before and after consecutive years of mass coral bleaching. We used data from surveys of commercial fishers, tourism operators, and coastal residents (n = 5254) conducted in 2013 and 2017. Threats perceived as most serious differed substantially among groups before bleaching but were strongly aligned after bleaching. Climate change became the most frequently reported threat by all stakeholder groups following the coral bleaching events, and perceptions of fishing and poor water quality as threats also ranked high. Within each of the 3 stakeholder groups, fishers, tourism operators, and coastal residents, the prioritization of these 3 threats tended to diverge in 2013, but convergence occurred after bleaching. These results indicate an emergence of areas of agreement both within and across stakeholder groups. Changes in perceptions were likely influenced by high-profile environmental-disturbance events and media representations of threats. Our results provide insights into the plasticity of environmental-threat perceptions and highlight how their convergence in response to major events may create new opportunities for strategic public engagement and increasing support for management.

Poblete, Jaime A., Dirks, Paul H.G.M., Chang, Zhaoshan, Huizenga, Jan Marten, Griessmann, Martin, and Hall, Chris (2021) The Watershed tungsten deposit, Northeast Queensland, Australia: Permian metamorphic tungsten mineralization overprinting Carboniferous magmatic tungsten. Economic Geology. (In Press)
The Watershed tungsten deposit (49.2 Mt avg 0.14% WO3) lies within the Mossman orogen, which comprises deformed Silurian-Ordovician metasedimentary rocks of the Hodgkinson Formation intruded by Carboniferous-Permian granites of the Kennedy Igneous Association. The Hodgkinson Formation in the Watershed area comprises skarn-altered conglomerate, psammite, and slate units that record four deformation events evolving from ductile, isoclinal, colinear folding with transposition (D1–D3) to brittle ductile shear zones (D4). Multiple felsic to intermediate dikes cut across the metasedimentary rocks at Watershed including: (1) Carboniferous, monzonite dikes (zircon U/Pb age of 350 ± 7 Ma) emplaced during D1–2; and (2) Permian granite plutons and dikes (zircon U/Pb ages of 291 ± 6, 277 ± 6, and 274 ± 6 Ma) and diorite (zircon U/Pb age of 281 ± 5 Ma) emplaced during D4. Tungsten mineralization is largely restricted to skarn-altered conglomerate, which preserves a peak metamorphic mineralogy formed during ductile deformation and comprises garnet (Grt40–87 Alm0–35Sps1–25Adr0–16), actinolite, quartz, clinopyroxene (Di36–59Hd39–61Jhn1–5), and titanite. A first mineralization event corresponds to the crystallization of disseminated scheelite in monzonite dikes (pre-D3) and adjacent units, with scheelite grains aligned in the S1–2 fabric and affected by D3 folding. This event enriched the Hodgkinson Formation in tungsten. The bulk of the scheelite mineralization formed during a second event and is concentrated in multistaged, shear-related, quartz-oligoclase-bearing veins and vein halos (muscovite 40Ar-39Ar weighted average age of 276 ± 6 Ma), which were emplaced during D4. The multistage veins developed preferentially in competent, skarn-altered conglomerate units and formed synchronous with four retrograde alteration stages. The retrograde skarn minerals include clinozoisite after garnet, quartz, plagioclase, scheelite, and phlogopite with minor sodium-rich amphibole, which formed during retrograde stages 1 and 2, accompanied by later muscovite, calcite, and chlorite formed during retrograde stage 3. Retrograde stage 4 was a late-tectonic, noneconomic sulfide stage. The principal controls on scheelite mineralization at Watershed were the following: (1) early monzonite dikes enriched in scheelite; (2) D4 shear zones that acted as fluid conduits transporting tungsten from source areas to traps; (3) skarn-altered conglomerate lenses that provide a competent host to facilitate vein formation and a source for calcium to form scheelite; and (4) an extensional depositional environment characterized by vein formation and normal faulting, which provide trapping structures for tungsten-bearing fluids, with decompression being a likely control on scheelite deposition. The coexistence of scheelite with oligoclase in monzonite dikes and veins suggests that tungsten was transported as NaHWO4⁠. Exploration in the area should target Carboniferous monzonite, associated with later syn-D4 shear zones cutting skarn-altered conglomerate.

Ziegler, Alan D., Lim, H.S., Wasson, Robert J., and Williamson, Fiona C. (2021) Flood mortality in SE Asia: can palaeo‐historical information help save lives? Hydrological Processes, 35 (1). e13989.
[Excerpt] Asia is one of the world's most flood-prone regions by many metrics: high flood magnitudes, frequency, severity; the number countries affected, the area of inundation; the number of people at risk; and importantly, flood-related fatalities (AIR, 2014; Luo, Maddoks, Iceland,Ward, & Winsemius, 2015; Table 1). With respect to mortality, nearly all the countries with more than 5,000 flood-related deaths since 1985 are from Asia (11 of 13; Table 1; Figure 1). As we write this commentary, flooding associated with tropical storm Nangka has caused more than 40 deaths in Laos, Cambodia, and Vietnam(Floodlist, 2020).

Spence, Joshua S., Sanislav, Ioan V., and Dirks, Paul H.G.M. (2021) 1750–1710 Ma deformation along the eastern margin of the North Australia Craton. Precambrian Research, 353. 106019.
In this contribution, we present field-based evidence that in the Mary Kathleen Domain from the Eastern Fold Belt of the Mount Isa Inlier the 1790–1750 Ma metasediments of the Leichhardt Superbasin were sheared and folded between 1750 and 1710 Ma. The Mary Kathleen Domain consists of a series of anastomosing high and low strain domains intruded syn- to late-tectonically by a series of 1740–1710 Ma felsic and mafic plutons and dykes. The timing relationships in the high strain domains are unclear due to mylonitisation and transposition but in the lower strain domains are well-preserved. The earliest deformation, D1, consists of a series of low angle truncation surfaces and shear zones that are folded around large scale N-S trending upright folds during D2. The D2 folds were refolded during D3 along NW to EW trending fold axes. An undeformed granitic pluton from the Mt Godkin area dated at ~1710 Ma that crosscuts the D2-D3 folds and the youngest detrital zircon population of ~1750 Ma constrains the timing of D1-D3 deformation between 1750 and 1710 Ma. Later, N-S (D4) and N-E (D5) trending brittle-ductile shears are interpreted to indicate a late Isan Orogeny overprint. The occurrence of contemporaneous folding in the Western Fold Belt suggests that between 1750 and 1710 Ma the eastern margin of the North Australia Craton was experiencing a significant deformation event that can be correlated with similarly aged deformation events from other parts of the North Australia Craton, from South Australia Craton and from East Antarctica. Following the assembly of most of the Nuna Supercontinent by 1.8 Ga, we postulate that the 1750–1710 Ma deformation and plutonism observed in Mount Isa Inlier is part of a series of worldwide orogenic events that contributed to the final configuration of the Nuna Supercontinent.

Palma, Ana C., Goosem, Miriam, Fensham, Roderick J., Goosem, Steve, Preece, Noel D., Stevenson, Pablo R., and Laurance, Susan G.W. (2021) Dispersal and recruitment limitations in secondary forests. Journal of Vegetation Science. e12975. (In Press)
Aims: Secondary forests are expanding rapidly in tropical regions and could play an important role in conserving native biodiversity and stabilising global climate. The recovery rate of plant communities in secondary forests varies considerably due to mechanisms associated with seed dispersal and recruitment dynamics. We explored these mechanisms along a chronosequence of tropical secondary forests in an agricultural landscape that was extensively cleared. Location: We explored these mechanisms along a chronosequence of secondary forests in tropical Australia. Methods: We used selected plant traits to characterise plant species and compared community composition between demographic stages (i.e. soil seedbank, understorey and overstorey) and forest age categories. We collected soil samples to assess seedbank composition and used quadrants and transects to assess understorey and overstorey plant community composition at each site. Results: For all demographic stages, we found that young (4-12 years) and intermediate-aged forests (16-20 years) were dominated by early successional, small-seeded species and traits associated with disturbed forests. In old secondary forest (23-34 years) some traits associated with late successional stages were present (e.g. large seeds, trees). However, the traits and species composition of mature forests remained distinct from all secondary forests. Across the chronosequence, forest age and demographic stage were significant factors in discriminating species and trait composition between forest sites. We found clear plant community similarities within demographic stages, despite the forest age differences. This suggests stronger limitations to dispersal and recruitment between demographic stages than between forest ages. Conclusions: Our results show that secondary forests in this region assemble slowly with dispersal and recruitment limitations constraining their recovery. Although a successional transition in species and plant traits composition along the chronosequence is clear, similarities to mature forests remain low. The slow recovery of late successional and large-seeded species in these secondary forests suggests that active restoration of such species may be necessary if we want to enhance the capacity of these forests to conserve native biodiversity.

Younes, Nicolas, Joyce, Karen E., and Maier, Stefan M. (2021) All models of satellite-derived phenology are wrong, but some are useful: a case study from northern Australia. International Journal of Applied Earth Observation and Geoinformation, 97 (102285).
Satellite-derived phenology (or apparent phenology) is frequently used to illustrate changes in plant phenology (i.e. true phenology) and the effects of climate forcing. However, each study uses a different method to detect phenology. Plant phenology refers to the relationship between the life cycle of plants and weather and climate events. Phenology is often studied in the field, but recently studies have transitioned towards using satellite images to monitor phenology at the plot, country, and continental scales. The problem with this approach is that there is an ever-increasing variety of earth observation satellites collecting data with different spatial, spectral, and temporal characteristics. In this paper we ask if studies that detect phenology using different sensors over the same site produce comparable results. Mangrove forests are one example where different methods have been used to examine their apparent phenology. In general, plant phenology, including mangroves, is described using few individual plants, but continental-scale descriptions of phenological events are scarce or inexistent. Few attempts have been made to describe the phenology of mangroves using satellite imagery, and each study presents a different method. We hypothesize that apparent phenology changes with: 1) areal extent; 2) site location; 3) frequency of observation; 4) spatial resolution; 5) temporal coverage; and 6) the number of cloud contaminated observations. Intuitively, one would assume that these hypotheses hold true, yet few studies have investigated this. For example, one would expect that clouds change the observed phenology of vegetation, that the number of species captured at spatial resolution will impact the apparent phenology, or that mangroves in different places display different phenologies, but how are these changes represented in the apparent phenology? We use the Enhanced Vegetation Index (EVI) to examine the changes in the start of season and peak growing season dates, as well as the shape and amplitude of the apparent phenology in each hypothesis. We use Landsat and Sentinel 2 imagery over the mangrove forests in Darwin Harbour (Northern Territory, Australia) as a case study, and found that apparent phenology does change with the sensor, site, and cloud contamination. Importantly, the apparent phenology is comparable between Landsat and Sentinel 2 sensors, but it is not comparable to phenology derived from MODIS. This is due to differences in the spatial resolution of the sensors. Cloud contamination also significantly changes the apparent phenology of vegetation. In this paper we expose the complexity of modelling phenology with remote sensing and help guide future phenology investigations.

Rowe, Cassandra, Wurster, Christopher M., Zwart, Costijn, Brand, Michael, Hutley, Lindsay B., Levchenko, Vladimir, and Bird, Michael I. (2021) Vegetation over the last glacial maximum at Girraween Lagoon, monsoonal northern Australia. Quaternary Research, 102. pp. 39-52.
Northern Australia is a region where limited information exists on environments at the Last Glacial Maximum (LGM). Girraween Lagoon is located on the central northern coast of Australia and is a site representative of regional tropical savanna woodlands. Girraween remained a perennial waterbody throughout the LGM, and as a result retains a complete proxy record of last glacial climate, vegetation and fire. This study combines independent palynological and geochemical analyses to demonstrate a dramatic reduction in tree cover, woody richness and expansion of grassland relative to current vegetation at the site. The process of tree decline was primarily controlled by the cool-dry glacial climate and CO2 effects, though more localised site characteristics restricted wetland associated vegetation. Fire processes played less of a role determining vegetation than in the Holocene and modern day, with reduced fire activity consistent with significantly lower biomass available to burn. This unique and detailed palaeoecological record provides the opportunity to explore and assess modelling studies of vegetation distribution during the LGM, particularly where a number of different global vegetation and/or climate simulations are inconsistent for northern Australia, and at a range of resolutions.

Zhao, Xu, Fu, Lebing, Wei, Junhao, Huizenga, Jan, Liu, Yan, Chen, Jiajie, and Wang, Dianzhong (2021) Generation and structural modification of the giant Kengdenongshe VMS-type Au-Ag-Pb-Zn polymetallic deposit in the East Kunlun Orogen, East Tethys: constraints from geology, fluid inclusions, noble gas and stable isotopes. Ore Geology Reviews, 131. 104041.
The Kengdenongshe giant Au-Ag-Pb-Zn polymetallic deposit is located in the East Kunlun Orogen (EKO). It contains about 42.2 t of Au, 608.6 t of Ag and 1.05 Mt of Pb and Zn with an average grade of Au 2.31 g/t, Ag 19.29 g/t and Pb + Zn 3.49 wt% (Pb: 1.23 wt%, Zn: 2.26 wt%). The NWW-trending ore bodies are predominantly hosted in Late Permian to Triassic rhyolitic tuff, which formed during Late Permian back-arc extension to Triassic arc-continental collision. The ore bodies are subdivided into Pb-Zn rich ore bodies on the top with high grades of Pb and Zn and low grades of Au and Ag, and Au-Ag rich ore bodies below with high grades of Au and Ag and low grades of Pb and Zn. The Pb-Zn rich ore bodies occur as vein, stockwork, and in breccia, and comprise quartz, pyrite, galena, sphalerite, and small amounts of chalcopyrite. The Au-Ag rich ore bodies consist of auriferous barite-sulfide-oxide veins and contain barite, pyrite (early strawberry and oolitic pyrite and later eu- to subhedral pyrite), galena, sphalerite, chalcopyrite, tetrahedrite and covellite. Gold is present as electrum, kustelite and native gold and silver is present as polybasite, pearceite, kongsbergite, and as minor native silver in microfractures in sulfides. The hydrothermal alteration minerals include, from bottom to top, quartz + barite + calcite around the Au-Ag rich orebodies, quartz + chlorite + epidote around the Pb-Zn rich orebodies, and quartz + K-feldspar within the tuff. Fluid inclusions from both the Pb-Zn rich and the Au-Ag rich orebodies consist of two phases (V–L-type) fluid inclusions of which the vapor phase has a size of 10–40 vol%. Fluid inclusions microthermometry reveal homogenization temperatures of fluid inclusions in Pb-Zn rich and Au-Ag rich ore bodies of 128–230 °C and 110–320 °C, with corresponding salinities of 0.7–9.9 and 0.2–18.3 wt% NaCl equivalent, respectively. H-O-S-Pb stable isotope and He-Ar noble gas isotope data indicate a mixed magmatic water-seawater source for both the Pb-Zn and Au-Ag rich ore bodies, and an additional meteoric water component for the Au-Ag rich ore bodies. The Pb-Zn and Au-Ag rich ore bodies share the same sulfur and lead sources, i.e. sulfur is derived from crustal magma and seawater/marine sulfate, and the lead originated from a mixed magmatic-ancient crustal sedimentary source. Collectively, the regional geology, mineralogy, alteration, and geochemistry indicate that the Kengdenongshe Au-Ag-Pb-Zn polymetallic deposit can be characterized as a VMS-type (volcanic-associated massive sulfide) deposit. Formation of the ore-hosting rhyolite tuff and mineralization are associated with Late Permian to Triassic marine volcanic exhalation. Middle to Late Triassic basin closure and arc-continent collision modified the deposit and resulted in the location inversion of the Pb-Zn and Au-Ag rich orebodies.

Huang, Han‐Xiao, Dai, Zuo-Wen, Liu, Hong, Li, Guang‐Ming, Huizenga, Jan Marten, Zhang, Lin‐Kui, Huang, Yong, Cao, Hua‐Wen, and Fu, Jian‐Gang (2021) Zircon U–Pb ages, geochemistry, and Sr–Nd–Pb–Hf isotopes of the Mugagangri monzogranite in the southern Qiangtang of Tibet, western China: implications for the evolution of the Bangong Co‐Nujiang Meso‐Tethyan Ocean. Geological Journal. (In Press)
We present in-situ zircon laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U–Pb ages, whole-rock geochemistry, and Sr–Nd–Pb–Hf isotopes of the Mugagangri monzogranite in the southern margin of the Qiangtang Block, Tibet, western China. The zircons yield a U–Pb age of ca. 123 Ma. The hornblende-bearing monzogranite shows metaluminous to weak peraluminous and high-K calc-alkaline characteristics exemplified by high silica (SiO2 = 67.57–70.57 wt%), high aluminium (Al2O3 = 14.68–15.78 wt%), high potassium (K2O = 4.00–5.14 wt%), high alkali (K2O + Na2O = 7.88–8.62 wt%), and low calcium contents (CaO = 1.72–2.17 wt%), with the aluminium saturation index (A/CNK) ranging from 0.98 to 1.09, suggesting that the Mugagangri monzogranite is a metaluminous to weak peraluminous I-type high-K calc-alkaline granite. Geochemically, similar to the arc magmas, the monzogranite is enriched in large-ion lithophile elements, and relatively depleted in high-field-strength elements. The monzogranite displays relatively high(87Sr/86Sr)i values (0.70972–0.71240), uniform εNd(t) values (−2.24 to −3.40), variable zircon εHf(t) values (−14.1 to +8.0), and high radiogenic Pb isotopic values (206Pb/204Pb = 18.588–18.790, 207Pb/204Pb = 15.616–15.642, and 208Pb/204Pb = 38.838–39.053). These geochemical characteristics indicate that the monzogranite was derived from a mixed source comprising ancient crustal and mantle materials, and experienced frac- tional crystallization during emplacement. We propose that the parental magma of the Mugagangri monzogranite was most likely generated during northward subduction of the Bangong Coujiang Meso-Tethys Ocean.

Barzehkar, Mojtaba, Parnell, Kevin E., Mobarghaee Dinan, Naghmeh, and Brodie, Graham (2021) Decision support tools for wind and solar farm site selection in Isfahan Province, Iran. Clean Technologies and Environmental Policy. (In Press)
Optimizing the location of wind and photovoltaic solar power plants is a significant environmental management problem. The effectiveness of the site selection process for renewable energy systems (RES) could be strengthened by flexible spatial and environmental planning strategies using decision support systems (DSS) to critically identify the most productive, environmentally friendly and acceptable sites for the production of sustainable and reliable wind and solar energy. This study discusses hybrid DSS, using multi-criteria evaluation based on the analytical hierarchy process (AHP), a geographical information system (GIS), fuzzy logic, and a weighted linear combination (WLC) approach to determine optimal locations for renewable energy generation infrastructure. In the first stage, the most decisive factors for evaluating the site suitability were identified, based on experts' opinions. Next, raster layers of ecological and socioeconomic sub-criteria were prepared GIS software. After incorporating the raster maps of each parameter, fuzzy membership functions were applied to normalize each raster layer between 0 and 1. The relative weights of different indicators were calculated using super decision software. Prioritizing vital elements were performed using AHP. In the final stage, the WLC approach was utilized to amalgamate layers in the GIS environment, which afforded the final site suitability maps. In Isfahan Province, Iran, 26% of the land area was found to be highly suitable for solar farms with 18% being highly suitable for wind farms. The results illustrate that using and comparing the results from combinations of computer-based DSS are more likely to result in better decisions than using individual DSS tools for the determination of the most suitable sites for RES location.

McCoy-West, Alex J., Burton, Kevin W., Millet, Marc-Alban, and Cawood, Peter A. (2021) The chondritic neodymium stable isotope composition of the Earth inferred from mid-ocean ridge, ocean island and arc basalts. Geochimica et Cosmochimica Acta, 293. pp. 575-597.
Accurate knowledge of the composition of Earth’s major chemical reservoirs is fundamental for constraining all modern geochemical cycles. Basaltic rocks provide a direct way of sampling the composition of Earth’s inaccessible interior. Here, we present the first comprehensive neodymium (Nd) stable isotope analyses for a global compilation of mid-ocean ridge, ocean island, continental intraplate and island arc basalts using a double-spike technique. In these primitive magma compositions magmatic differentiation has no resolvable effect on δ146/144Nd. Mid-ocean ridge basalts possess an extremely homogenous δ146/144Nd with an average composition of δ146/144Nd = −0.025 ± 0.013‰ (±2 s.d.; n = 33). Ocean island and continental intraplate magmas possess more variable compositions (δ146/144Nd = 62 ppm) that are related to the variable incorporation of recycled components in their source regions. Island arc basalts from New Britain (δ146/144Nd = 61 ppm) reflect the complex interplay between source composition, degree of melting and slab-fluid inputs. Variations are uncorrelated with indicators of magmatic differentiation or slab-fluid addition, rather increasing δ146/144Nd with slab depth is attributed to a higher proportion of metasomatized sub-arc mantle in the melting region. A partial melting model for Nd stable isotopes has been constructed using Nd–O force constants calculated using the Born-Lande approximation. Melting of typical mantle peridotite will induce no resolvable fractionations of Nd stable isotopes (Δ146/144Ndmelt-mantle < 0.003‰ at 1200 °C). The lack of fractionation upon partial melting means primitive magmatic rocks can be used to calculate the average composition of the bulk silicate Earth (BSE), which is δ146/144Nd = −0.024 ± 0.031‰ (±2 s.d.; n = 80). This BSE composition is indistinguishable at the 95 % confidence level from that of chondritic meteorites, the building blocks of Earth. Therefore, sequestration of significant quantities of Nd into the sulfide matte did not occur, this combined with recent experimental evidence for no Sm-Nd fractionation means the sulfide matte cannot be considered a plausible solution for the 142Nd/144Nd offset between the Earth and chondrites. Despite resolvable variations in δ146/144Nd from the canonical value being widespread in terrestrial materials, they are not large enough to generate the difference in radiogenic Nd isotope ratios between the BSE and chondrites.

Koci, Jack, Wilkinson, Scott N., Hawdon, Aaron A., Kinsey-henderson, Anne E., Bartley, Rebecca, and Goodwin, Nicholas R. (2021) Rehabilitation effects on gully sediment yields and vegetation in a savanna rangeland. Earth Surface Processes and Landforms. (In Press)
Gully rehabilitation can contribute to catchment management by stabilising erosion and reducing downstream sediment yields, yet the globally observed responses are variable. Developing the technical basis for gully rehabilitation and establishing guidelines for application requires studies that evaluate individual rehabilitation measures in specific environments. An eight-year field experiment was undertaken to evaluate sediment yield and vegetation responses to several gully rehabilitation measures. The rehabilitation measures aimed to reduce surface runoff into gully head cuts, trap sediment on gully floors and increase vegetation cover on gully walls and floors. The study occurred in a savanna rangeland in northeast Australia. Two gullies were subject to treatments while four gullies were monitored as untreated controls. A runoff diversion structure reduced headcut erosion from 4.3 to 1.2 m2 y-1. Small porous check dams and cattle exclusion reduced gully total sediment yields by more than 80 percent, equivalent to a reduction of 0.3–2.4 t ha-1 y-1, but only at catchment areas less than 10 ha. Fine sediment yields (silt and clay) were reduced by 7 and 19 percent from the two treated gullies, respectively. The porous check dam deposits contained a lower percentage of the fine fraction than the parent soil. Significant regeneration of gully floor vegetation occurred, associated with trapping of organic litter and fine sediment. Increases in vegetation cover and biomass were comprised of native perennial grasses, trees and shrubs. In variable climates, long-term gully rehabilitation will progress during wetter periods, and regress during droughts. Understanding linkages between rehabilitation measures, their hydrologic, hydraulic and vegetation effects and gully sediment yields is important to defining the conditions for their success.

Po, Sovinda, and Sims, Kearrin (2021) The myth of non-interference: Chinese foreign policy in Cambodia. Asian Studies Review. (In Press)
The discourse of “non-interference” features prominently in China’s so-called “peaceful rise” and “win – win” approach to international diplomacy. This article contests Beijing’s non-interference rhetoric through a case-study analysis of Cambodia. We make two core arguments: first, interference by foreign powers is not limited to actions that challenge a regime’s leadership, but can also include the reinforcement of regimes that lack popular support. Second, Beijing’s “non-interference” rhetoric is not demonstrated in the context of Cambodia, where it has repeatedly interfered to reinforce Prime Minister Hun Sen’s leadership during times of political contestation. To make these arguments, the article offers a historical summary of Chinese interference in Cambodia followed by an analysis of the key domains in which Hun Sen’s regime supports Chinese geostrategic interests. These are: support for Beijing’s One China Policy and its Belt and Road Initiative; support for Beijing in negotiations with ASEAN; and support for Chinese economic interests. Collectively, we argue that these domains contribute to the advancement of China’s “core national interest”, and it is therefore a myth to suggest that China has not interfered in Cambodia’s domestic politics.

Wang, Yue, Zhu, Xiangkun, Tang, Chao, Mao, Jingwen, and Chang, Zhaoshan (2021) Discriminate between magmatic- and magmatic-hydrothermal ore deposits using Fe isotopes. Ore Geology Reviews, 130. 103946.
Although discriminating high temperature mineral systems, for example, magmatic- vs magmatic-hydrothermal origin Fe deposits, is challenging, the emerging Fe isotope systematics have shown good potentials to provide crucial information on resolving the problem. Here, Fe isotopes of multiple types of samples from one iron oxide-apatite (IOA) deposit and two skarn Fe deposits are measured, aiming to study their behaviors in high temperature magmatic and magmatic-hydrothermal environments. The primary observation of this study is that magnetite samples from high grade ores of magmatic origin IOA deposits has a heavier Fe isotopic signature relative to the associated igneous rocks, whereas a lighter Fe isotopic composition in magnetite samples from magmatic-hydrothermal origin skarn deposits relative to the causative intrusions. Another distinctive feature is that δ56Fe values of the causative intrusions in the magmatic origin IOA deposits are lighter than that of non-fertile intrusions, whereas the ore-associated intrusions of the magmatic-hydrothermal deposit are heavier in δ56Fe than that of non-fertile igneous rocks. The above two observed scenarios suggest that Fe isotope fractionation exists in both magmatic immiscibility and hydrothermal fluid exsolution processes. Magma immiscibility leads to heavy Fe isotope enrichment in immiscible Fe-rich melt phase, and resulting light Fe enrichment in Si-rich melt phase. Hydrothermal fluid exsolution results in lighter Fe isotope enrichment in the exsolved liquid phase, with a heavy Fe isotope enrichment in the residual magma. Fe isotopes behave in different ways in magmatic and magmatic-hydrothermal mineralization processes, which makes Fe isotopes an effective tool to discriminate mineral deposits of magmatic origin from those formed by magmatic-hydrothermal processes.

Fujii, Toshiyuki, Kato, Chizu, Mahan, Brandon, and Moynier, Frédéric (2021) Study on the Isotope fractionation of Zinc in Complexation with Macrocyclic Polyethers. Zeitschrift fuer Anorganische und Allgemeine Chemie, 647 (6). pp. 599-605.
Isotope fractionation of Zn was studied via liquid-liquid extraction with aqueous phase of ZnCl2/HCl and organic phase of crown ethers(CEs), including benzo15-crown-5(B15C5), benzo-18-crown-6(B18C6) and Dicyclohexano-24-crown-8(DC24C8)/1,2- dichloroethane. The isotope enrichment factor (ϵ66), expressed in permil notation, of the isotope pair 66Zn−64Zn was found to be between −0.24 and −0.52 ‰ in the order of enrichment: B15C5≥B18C6>DC24C8. The magnitude of ϵ66was well explained by theoretical isotope fractionation factors obtained by density functional theory method for zinc chloride and ZnCl2/CE model molecules, and a thermochemical description that correlates ϵ66 with the differences in Gibbs free energy(ΔG) of the exchange reaction, here termed δΔG, based on the mass differences of Zn isotopes involved. Finally, results suggest that ϵ66 may be used as a diagnostic and metric of Zn metabolic derangement, such as in porphyrias.

 Find more publications @ JCU Research Online