Journal articles on the topic 'Water shortage (Australia'
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1
Martínez, Gustavo, and María A. Gutiérrez. "Early Holocene water well in the Pampas of Argentina: Human responses to water shortage events." Holocene 29, no. 1 (October 24, 2018): 145–57. http://dx.doi.org/10.1177/0959683618804643.
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Water wells are ethnographically and archaeologically described in Australia and the plains of North America. Recently, a prehistoric water well from the early Holocene was recorded in the Pampas of Argentina. The aim of this paper is to present the main characteristics of the water well, considering its form, dimension, sediment analyses (texture and chemical parameters), and material culture content. This is the first water well recorded in the Pampas of Argentina. Consequently, a discussion about natural or cultural origins of this kind of features is provided. An evaluation of similarities and differences with well-described water wells from the United States and Australia is included in order to highlight the cultural origin of the pit. Also, the meaning of the cultural response to water availability in terms of early-Holocene hunter–gatherer adaptations as well as the implications of this strategy for understanding paleoenvironmental scenarios of the Pampas of Argentina are discussed. The well seems to have mitigated an exceptional lack of surface water in the eastern Pampas or offered an alternative for the non-drinkable quality of the available surface water. The strategy of digging water wells was available in the behavioral repertoire of the Pampean hunter–gatherer populations as early as c. 8700–8000 14C yr BP ( c. 9700–8800 cal. yr BP), as these groups were fairly flexible and resilient in dealing with short-term shortages of water.
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Turner, NC. "Crop production on duplex soils: an introduction." Australian Journal of Experimental Agriculture 32, no. 7 (1992): 797. http://dx.doi.org/10.1071/ea9920797.
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Duplex or texture-contrast soils occur over about 60% of the agricultural areas of south-west Western Australia. Annual crops of wheat, barley, oats, and lupins predominate on these soils, grown in rotation with annual pastures. The climate is characterised by cool, wet winters and hot, dry summers. Crop production is restricted to the winter and spring and is limited by waterlogging in the wet winter months and by water shortage during grain filling in spring. Research on crop production on duplex soils has been undertaken for the past 8 years by a collaborative team from the CSIRO Dryland Crops andyoils Program and the Western Australian Department of Agriculture. This research has been focussed on 3 sites at which processes limiting crop production on duplex soils have been highlighted. This special issue was initiated to summarise that research and to put it in its regional and national perspective. Additionally, opportunity was taken to compare and contrast experiences both within Western Australia and throughout Australia, and to draw out management options for crop production on duplex soils.
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Cary, J. W. "Influencing attitudes and changing consumers' household water consumption behaviour." Water Supply 8, no. 3 (September 1, 2008): 325–30. http://dx.doi.org/10.2166/ws.2008.078.
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Programs for demand management have become critical following extended water shortage in Australia. Changing attitudes is a major element of water conservation programs. Information and education are likely to be necessary but not sufficient components of any program for behaviour change. A combination of factors is needed to promote water saving behaviour. Changing the behaviours of less responsive water users requires a better understanding of what shapes water conservation behaviours. Programs and conservation behaviour models need to take account of both ‘internal’ influences, such as attitudes and habits, and ‘external’ influences, such as the water delivery environment, pricing and social norms for water use.
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Yoon, Dong-Hyun, Won-Ho Nam, Min-Gi Jeon, Hyun-Uk An, Do-Guen Yoo, and Moojong Park. "Assessment of Regional Drought Preparedness and Response Capacity on the Basis of Water Resources Shortage." Journal of the Korean Society of Hazard Mitigation 22, no. 2 (April 30, 2022): 39–46. http://dx.doi.org/10.9798/kosham.2022.22.2.39.
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Due to global climate change and weather fluctuations, weather phenomena such as global warming and increasing carbon dioxide concentration are intensifying. Climate change increases the frequency of natural disasters and has been affecting the occurrence of drought. In recent years, severe drought has been occurring all over the world. California in the United States experienced a mega drought from 2006 to 2016, Australia experienced a millennium drought from 2001 to 2009, and the Central and Northern African continent suffered a mega drought from 2005 to 2018. With regard to extreme drought events, depletion of water resources has continued for a long time, causing enormous damage that is difficult to restore socially and economically. Drought response strategy for South Korea has focused on drought recovery and emergency measures for drought damage. To respond to severe drought events, it is necessary to evaluate regional drought response capacity and drought preparedness. In this study, long-term water resource comprehensive plan, water management yearbook, and water statistics were used to evaluate drought response capabilities according to region, including resilience analysis such as local economy, drought preparation system, and drought training. The water resource shortage of each local government was calculated based on water demand and supply data, and drought response capability of the local government was analyzed by combining it with resilience analysis for drought. The results of this study can be used for long-term drought preparedness and establishment of countermeasures in the future through the evaluation of drought response capacity according to region.
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C. Paton, David. "Windows and missed opportunities." Pacific Conservation Biology 9, no. 2 (2003): 83. http://dx.doi.org/10.1071/pc030083.
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WATER rationing has been introduced in most of the larger cities of southern Australia as a consequence of a shortage of water. The rationing is implemented by limiting the timing (to cooler parts of the day) and frequency with which gardens can be watered, and preventing unneeded waste, such as cleaning vehicles and concrete paths with hoses. There is, however, no guarantee that this method will lead to less water being used and no predetermined target for the level of reduction required. Few people complain about this type of rationing because the quality of our lives has not altered. But what if the requirement was for every one of us to reduce our current water consumption by at least 20% or perhaps to have an absolute limit placed on the volume of water we could use. How would we use the ration of water that we were allocated?
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Smith, Phil, Grahame Collier, and Hazel Storey. "As Aussie as Vegemite: Building the Capacity of Sustainability Educators in Australia." Australian Journal of Environmental Education 27, no. 1 (2011): 175–85. http://dx.doi.org/10.1017/s0814062600000161.
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AbstractVegemite, a thick, rich and salty product made from yeast extract, is a paste commonly spread on bread or toast in Australian households. This iconic product mirrors some of the unique aspects of this country. For example, Vegemite thinly spread is best. The population of this country is sparse across the wide lands, and the Australian environment with its thin soils, water shortages and intense climates, might also be described as spread thin. These aspects of context present challenges because Australia needs quality sustainability educators thick on the ground to deal with the many and diverse environmental issues.This paper describes the development of the Australian National Professional Development Initiative for Sustainability Educators (NPDISE) and how it was infuenced by the Australian context. Multiple challenges existed: the size of the country, its environmental conditions and rich biodiversity, distance and space between major centres, distribution of people and resources, understanding of and support for education, and three tiers of government – each with its own policies, programs and priorities. On top of this, the practice of sustainability education crosses multiple professional sectors and disciplines. All these challenges had to be taken into account.Research conducted by the Waste Management Association Australia in 2009 revealed that the needs of Australia's sustainability educators in overcoming many of these challenges were broadly consistent around Australia. This gave encouragement to the establishment of a national professional development approach for those working in the environmental education feld. This paper shows how four professional associations – Australian Association for Environmental Education, Waste Management Association Australia, Australian Water Association, and the Marine Education Society of Australasia – worked together for the frst time and approached these challenges whilst developing the NPDISE. A 1954 jingle said Vegemite would help children “grow stronger every single week”. The NPDISE represents a similar ethos with an emphasis on building the sector.
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Kavehei, Emad, Syezlin Hasan, Carla Wegscheidl, Matthew Griffiths, James C. R. Smart, Carlos Bueno, Liz Owen, et al. "Cost-Effectiveness of Treatment Wetlands for Nitrogen Removal in Tropical and Subtropical Australia." Water 13, no. 22 (November 22, 2021): 3309. http://dx.doi.org/10.3390/w13223309.
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Treatment wetlands can reduce nitrogen (N) pollution in waterways. However, the shortage of information on their cost-effectiveness has resulted in their relatively slow uptake in tropical and subtropical Australia, including the catchments of the Great Barrier Reef and Moreton Bay. We assessed the performance of constructed treatment wetlands (CW) and vegetated drains (VD) that treat agricultural runoff, and of sewage treatment plant wetlands (STPW), which polish treated effluent. Treatment performance was estimated as changes in concentration (dissolved inorganic nitrogen, DIN, and total nitrogen, TN; mg L−1) and annual load reductions (kg N ha−1 yr−1). We calculated their cost-effectiveness by comparing their N removal against the costs incurred in their design, construction, and maintenance. Overall, CWs and VDs reduced DIN concentrations by 44% (0.52 to 0.29 mg L−1), and STPW reduced them by 91% (2.3 to 0.2 mg L−1); STPWs also reduced TN concentrations by 72%. The efficiency varied among sites, with the best performing CWs and VDs being those with relatively high inflow concentrations (>0.2 mg L−1 of DIN, >0.7 mg L−1 of TN), low suspended solids, high vegetation cover and high length: width ratio. These high performing CWs and VDs removed N for less than USD 37 kg−1 DIN (AUD 50 kg−1 DIN), less than the end-of-catchment benchmark for the Great Barrier Reef of USD 110 kg−1 DIN (AUD 150 kg−1 DIN). When adequately located, designed, and managed, treatment wetlands can be cost-effective and should be adopted for reducing N in tropical and subtropical Australia.
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Silburn, D. M., J. L. Foley, A. J. W. Biggs, J. Montgomery, and T. A. Gunawardena. "The Australian Cotton Industry and four decades of deep drainage research: a review." Crop and Pasture Science 64, no. 12 (2013): 1049. http://dx.doi.org/10.1071/cp13239.
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The Australian cotton industry and governments have funded research into the deep-drainage component of the soil–water balance for several decades. Cotton is dominantly grown in the northern Murray–Darling and Fitzroy Basins, using furrow irrigation on cracking clays. Previously, it was held that furrow irrigation on cracking clays was inherently efficient and there was little deep drainage. This has been shown to be simplistic and generally incorrect. This paper reviews global and northern Australian deep-drainage studies in irrigation, generally at point- or paddock-scale, and the consequences of deep drainage. For furrow-irrigated fields in Australia, key findings are as follows. (i) Deep drainage varies considerably depending on soil properties and irrigation management, and is not necessarily ‘very small’. Historically, values of 100–250 mm year–1 were typical, with 3–900 mm year–1 observed, until water shortage in the 2000s and continued research and extension focussed attention on water-use efficiency (WUE). (ii) More recently, values of 50–100 mm year–1 have been observed, with no deep drainage in drier years; these levels are lower than global values. (iii) Optimisation (flow rate, field length, cut-off time) of furrow irrigation can at least halve deep drainage. (iv) Cotton is grown on soils with a wide range in texture, sodicity and structure. (v) Deep drainage is moderately to strongly related to total rainfall plus irrigation, as it is globally. (vi) A leaching fraction, to avoid salt build-up in the soil profile, is only needed for irrigation where more saline water is used. Drainage from rainfall often provides an adequate leaching fraction. (vii) Near-saturated conditions occur for at least 2–6 m under irrigated fields, whereas profiles are dry under native vegetation in the same landscapes. (viii) Deep drainage leachate is typically saline and not a source of good quality groundwater recharge. Large losses of nitrate also occur in deep drainage. The consequences of deep drainage for groundwater and salinity are different where underlying groundwater can be used for pumping (fresh water, high yield; e.g. Condamine alluvia) and where it cannot (saline water or low yield; e.g. Border Rivers alluvia). Continuing improvements in WUE are needed to ensure long-term sustainability of irrigated cropping industries. Globally there is great potential for increased production using existing water supplies, given deep drainage of 10–25% of water delivered to fields and WUE of <50%. Future research priorities are to further characterise water movement through the unsaturated zone and the consequences of deep drainage.
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Tidemann, Sonia C. "Causes of the decline of the Gouldian Finch Erythrura gouldiae." Bird Conservation International 6, no. 1 (March 1996): 49–61. http://dx.doi.org/10.1017/s0959270900001301.
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SummaryPopulations of Gouldian Finch Erythrura gouldiae, an estrildid endemic to northern Australia, declined markedly during the last two or three decades. A survey revealed the species in two areas of Northern Territory, with an estimated 2,000 individuals, including juveniles. Recaptures were low either because of mortality or dispersal. Gouldian Finches eat predominantly Sorghum spp. seeds, but consume other seeds before Sorghum ripens. Other finches declined as cattle increased. Gouldian Finches breed in tree hollows of predominantly two species of eucalypts that grow on rocky slopes. They require water within about 4 km of the nest site. There was no shortage of nesting hollows at the known breeding sites. Fires in the early to mid-dry season allow birds access to seed without damaging trees, but later fires can destroy trees with nest hollows and remove shade. Average clutch-size is 5.2. About 72% of eggs laid, and 63% of nests, fledged young. Pairs lay up to three clutches in a season (February-August), the length of which may depend on rainfall during the preceding wet season. Air-sac mite (Sternostoma tracheacolum), found in 62% of Gouldian Finches sampled, may be preventing the species recovering to former numbers. New colonies of Gouldian Finches should be identified, populations monitored, and habitat managed by effecting patchy burns by low-intensity fires early in the dry season.
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Venkatesan, Srikanth, Mahzabin Afroz, Satheeskumar Navaratnam, and Rebecca Gravina. "Circular-Economy-Based Approach to Utilizing Cardboard in Sustainable Building Construction." Buildings 13, no. 1 (January 10, 2023): 181. http://dx.doi.org/10.3390/buildings13010181.
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Circular-economy-based sustainability approaches in construction are gaining wide acceptance due to the volume of waste generation and increasing demand for natural materials. Propelled by the recent timber shortage in Australia and the issues of waste management of cardboard, this study aims to analyse the possibilities of using cardboard as a construction material, based on its initial strength and multiple recycling options. A systematic review of research papers published in the last 40 years has been undertaken using a single keyword search to select the database. The review is presented in terms of the characteristics of the cardboard, dimensional stability, durability, structural strength, design, and analysis of cardboard. Recurring themes are evaluated using a latent Dirichlet allocation approach to identify the factors that ascertain the suitability of cardboard. Analysis reveals that despite certain constraints, such as water absorption and fire resistance, cardboard can be used as a replacement for timber by overcoming such limitations. This observation has benefits for the construction industry and the recycling industry. This study found that cardboard adheres to the circular economy principles, which should inspire policymakers. The paper concludes by highlighting the current circumstances and scientific challenges that impede the usage of cardboard in construction and recommends potential works needed to address these challenges for the benefit of practitioners and researchers.
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Bait-Suwailam, Tahani K., and Abdulrahim M. Al-Ismaili. "Review on Seawater Greenhouse: Achievements and Future Development." Recent Patents on Engineering 13, no. 4 (December 27, 2019): 312–24. http://dx.doi.org/10.2174/1872212113666181211151658.
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Background: Seawater greenhouse (SWGH) is a technology established to overcome issues related to open field cultivation in arid areas like high temperatures and freshwater shortage. So far, five pilot Seawater greenhouses were built around the world; in Spain, United Arab Emirates, Oman, Australia and Somaliland. All the patents related to the Seawater greenhouse components and designs mentioned were reviewed. Methods:: The Seawater greenhouse adopts the humidification-dehumidification (HDH) concept where evaporated moisture from saline water source is condensed to produce freshwater within the greenhouse body. Many advancements have been made throughout the past 25 years to optimize the Seawater greenhouse by means of structural improvement, heat distribution, condenser design and material, source of feed water and the evaporator via both trial-and-error and simulation approaches. The latter included numerical, mathematical, analytical and artificial neural network simulations. Various condenser designs were adopted in order to increase freshwater production to meet the irrigation demand of the seawater greenhouse. Results and Conclusion: To make the Seawater greenhouse self-sufficient in terms of energy production, the use of renewable energies and nonconventional sources was also investigated like the use of geothermal, solar and wind energy to produce electricity for the greenhouse operation and for other requirements as well. The use of reverse osmosis along with reverse electro dialysis to produce freshwater and electricity in the seawater greenhouse, was also one of the ideas suggested to improve and solve the associated constraints. Direct contact dehumidification is another development suggested to improve the condensation rate. This new approach seems to be very promising as it involves low capital, operation and maintenance costs, high freshwater production, and fouling- and corrosion-free.
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King, Lesley, Bridget Kelly, Joey Ho, and Libby Hattersley. "Water shortage in Australian fast food outlets." Australian and New Zealand Journal of Public Health 32, no. 5 (October 2008): 492. http://dx.doi.org/10.1111/j.1753-6405.2008.00288.x.
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Wang, Bingyu, Takashi Oguchi, and Lin Zhang. "Simulating impact of over-grazing on grassland degradation using GIS: a case study in the Heihe River Basin, China." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-389-2019.
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<p><strong>Abstract.</strong> Inland river basins in arid to semi-arid regions are widely distributed in Northwest China, Central Asia, Central Australia, and North Africa, and are often subject to significant human activities. The most distinctive natural feature of such basins is the shortage of water resources, and the pivotal reasons involve less precipitation and heavy evapotranspiration (ET). In recent years, intensive human activities also damage the natural environment of the basins. They result in many problems especially the deterioration of ecological environment which will lead to severe consequences such as desertification, sandstorm, the disappearance of wetlands, reduction of forest and grassland degradation. They prevent us from achieving the goal of sustainable development. How to balance economic development and ecosystem conservation and to realize the sense of sustainability in inland river basins will be vitally important.</p><p>The Heihe River is the second largest inland river in the Northwest of China with a long history development by human (Figure 1). Water resources from the river are crucial not only for the ecosystem but also for local human societies. The Heihe River Basin (HRB) is divided into three zones with different landscapes and natural environments. The upstream of HRB is the headstream which generates water resources mainly from glaciers and snow in Qilian Mountain. A large population of nomadic national minorities inhabits here and keeps animal husbandry as the primary production activity. In the early times, the Chinese government encouraged production activities to stimulate economic growth, and significant over-grazing and resultant severe grassland degradation occurred. Grassland is crucial for maintaining water resources especially in arid regions, without grasses most water will quickly evaporate into the air. Therefore, land resource management about grassland and the impact of human activities on the natural environment are of high research value in the HRB.</p><p>This research aims to investigate the impact of over-grazing on grassland degradation in the inland ecosystem of the HRB. The changes of grassland distribution were simulated under different over-grazing scenarios to provide a reference for resource management and the related decision-making process and to contribute to the sustainable development of the region.</p>
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Soltani, Ali, and Ehsan Sharifi. "Understanding and Analysing the Urban Heat Island (UHI) Effect in Micro-Scale." International Journal of Social Ecology and Sustainable Development 10, no. 2 (April 2019): 14–28. http://dx.doi.org/10.4018/ijsesd.2019040102.
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The shortage of vegetation cover alongside urban structures and land hardscape in cities causes an artificial temperature increase in urban environments known as the urban heat island (UHI) effect. The artificial heat stress in cities has a particular threat for usability and health-safety of outdoor living in public space. Australia may face a likely 3.8°C increase in surface temperature by 2090. Such an increase in temperature will have a severe impact on regional and local climate systems, natural ecosystems, and human life in cities. This paper aims to determine the patterns of the UHI effect in micro-scale of Adelaide metropolitan area, South Australia. The urban near-surface temperature profile of Adelaide was measured along a linear east-west cross-section of the metropolitan area via mobile traverse method between 26 July 2013 and 15 August 2013. Results indicate that the while the maximum UHI effect occurs at midnight in the central business district (CBD) area in Adelaide, the afternoon urban warmth has more temperature variations (point-to-point variation), especially during the late afternoon when local air temperature is normally in its peak. Thus, critical measurement of heat-health consequences of the UHI effect need to be focused on the afternoon heat stress conditions in UHIs rather than the commonly known night time phenomenon. This mobile traverse urban heat study of Adelaide supports the hypothesis that the UHI effect varies in the built environment during daily cycles and within short distances. Classical UHI measurements are commonly performed during the night – when the urban-rural temperature differences are at their maximum. Thus, they fall short in addressing the issue of excess heat stress on human participants. However, having thermally comfortable urban microclimates is a fundamental characteristic of healthy and vibrant public spaces. Therefore, urban planning professionals and decision makers are required to consider diurnal heat stress alongside nocturnal urban heat islands in planning healthy cities. The results of this article show that the diurnal heat stress varies in the built environment during daily cycles and within short distances. This study confirms that the maximum urban heat stress occurs during late afternoon when both overall temperature and daily urban warmth are at their peak. Literature indicates that diurnal heat stress peaks in hard-landscapes urban settings while it may decrease in urban parklands and near water bodies. Therefore, urban greenery and surface water can assist achieving more liveable and healthy urban environments (generalisation requires further research). A better understanding of daily urban warmth variations in cities assists urban policy making and public life management in the context of climate change.
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Mudd, Gavin M. "The Legacy of Early Uranium Efforts in Australia, 1906 - 1945: From Radium Hill to the Atomic Bomb and Today." Historical Records of Australian Science 16, no. 2 (2005): 169. http://dx.doi.org/10.1071/hr05013.
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The existence of uranium minerals has been documented in Australia since the late nineteenth century, and uranium-bearing ores were discovered near Olary ('Radium Hill') and in the Gammon Ranges (Mount Painter) in north-eastern South Australia early in the twentieth century. This occurred shortly after the discovery of radioactivity and the isolation of radium, and a mining rush for radium quickly began. At Radium Hill, ore was mined and concentrated on site before being transported to Woolwich in Sydney, where the radium and uranium were extracted and refined. At Mount Painter, the richness of the ore allowed direct export overseas. The fledgling Australian radium industry encountered many difficulties, with the scale of operations generally much smaller than at overseas counterparts. Remoteness, difficulties in treating the ore, lack of reliable water supplies and labour shortages all characterized the various attempts at exploitation over a period of about 25 years to the early 1930s. Hope in the potential of the industry, however, was eternal. When the British were working with the Americans during the Second World War to develop the atomic bomb, they secretly requested Australia to undertake urgent and extensive studies into the potential supply of uranium. This led to no exports but it did lay the groundwork for Australia's post-war uranium industry that has dominated the nation's nuclear diplomacy ever since. Some three decades later, the modest quantity of radioactive waste remaining at Woolwich was rediscovered, creating a difficult urban radioactive waste dilemma. The history of both the pre-war radium–uranium industry and Australia's involvement in the war-time exploration work is reviewed, as well as the radioactive waste problems resulting from these efforts, which, despite their relatively small scale, persist and present challenges in more modern times.
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An, Subang, Xingtu Liu, Bolong Wen, Xiaoyu Li, Peng Qi, and Kun Zhang. "Comparison of the Photosynthetic Capacity of Phragmites australis in Five Habitats in Saline‒Alkaline Wetlands." Plants 9, no. 10 (October 6, 2020): 1317. http://dx.doi.org/10.3390/plants9101317.
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Water shortages have an important impact on the photosynthetic capacity of Phragmites australis. However, this impact has not been adequately studied from the perspective of photosynthesis. An in-depth study of the photosynthetic process can help in better understanding the impact of water shortages on the photosynthetic capacity of P. australis, especially on the microscale. The aim of this study is to explore the photosynthetic adaptation strategies to environmental changes in saline‒alkaline wetlands. The light response curves and CO2 response curves of P. australis in five habitats (hygrophilous, xerophytic, psammophytic, abandoned farmland, paddy field drainage) in saline‒alkaline wetlands were measured at different stages of their life history, and we used a nonrectangular hyperbolic model to fit the data. It was concluded that P. australis utilized coping strategies that differed between the growing and breeding seasons. P. australis in abandoned farmland during the growing season had the highest apparent quantum efficiency (AQE) and photosynthetic utilization efficiency for weak light because of the dark environment. The dark respiration rate of P. australis in the drainage area of paddy fields was the lowest, and it had the highest values for photorespiration rate, maximum photosynthetic rate (Pmax), photosynthetic capacity (Pa), biomass, maximum carboxylation rate (Vcmax), and maximum electron transfer rate (Jmax). The light insensitivity of P. australis increased with the transition from growing to breeding season, and the dark respiration rate also showed a downward trend. Moreover, Vcmax and Jmax would decline when Pmax and Pa showed a declining trend, and vice versa. In other words, Vcmax and Jmax could explain changes in the photosynthetic capacity to some extent. These findings contribute to providing insights that Vcmax and Jmax can directly reflect the variation in photosynthetic capacity of P. australis under water shortages in saline‒alkaline wetlands and in other parts of world where there are problems with similarly harmful environmental conditions.
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Schwartz, Andrew J., Hamish A. McGowan, Alison Theobald, and Nik Callow. "Quantifying the impact of synoptic weather types and patterns on energy fluxes of a marginal snowpack." Cryosphere 14, no. 8 (August 28, 2020): 2755–74. http://dx.doi.org/10.5194/tc-14-2755-2020.
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Abstract. Synoptic weather patterns are investigated for their impact on energy fluxes driving melt of a marginal snowpack in the Snowy Mountains, southeast Australia. K-means clustering applied to ECMWF ERA-Interim data identified common synoptic types and patterns that were then associated with in situ snowpack energy flux measurements. The analysis showed that the largest contribution of energy to the snowpack occurred immediately prior to the passage of cold fronts through increased sensible heat flux as a result of warm air advection (WAA) ahead of the front. Shortwave radiation was found to be the dominant control on positive energy fluxes when individual synoptic weather types were examined. As a result, cloud cover related to each synoptic type was shown to be highly influential on the energy fluxes to the snowpack through its reduction of shortwave radiation and reflection/emission of longwave fluxes. As single-site energy balance measurements of the snowpack were used for this study, caution should be exercised before applying the results to the broader Australian Alps region. However, this research is an important step towards understanding changes in surface energy flux as a result of shifts to the global atmospheric circulation as anthropogenic climate change continues to impact marginal winter snowpacks.
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Gregory, Jenny. "“A Spirit of Bolshevism?”: Perth’s Water Crisis of the 1920s." Journal of Urban History 46, no. 1 (February 17, 2017): 79–97. http://dx.doi.org/10.1177/0096144217692989.
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The early 1920s were a pivotal period in Perth’s water history, marked by conflict over the inadequacies of the city’s water supply. Only a small area of the city had reticulated water; most people relied on wells or rainwater tanks. Water shortages, particularly in new suburbs and higher districts, prompted the Western Australian Government to impose water restrictions. The press, local government authorities, and opposition politicians took the government to task, and officials and householders protested at public meetings. This article analyzes the causes of water shortages, the level of protest, tensions over the governance of the water supply, and the response of the state government. As on America’s west coast in the same period, government decision making was often influenced by rural needs, but the role played by urban householders, with the support of the press and opposition politicians, was paramount in shaping new water supply systems for city dwellers.
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Aldirawi, Safaa, Regina Souter, and Cara D. Beal. "Barriers and opportunities for behavior change in managing high water demand in water scarce Indigenous communities: an Australian perspective." Journal of Water, Sanitation and Hygiene for Development 9, no. 4 (October 22, 2019): 765–73. http://dx.doi.org/10.2166/washdev.2019.091.
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Abstract Managing water demand by reducing water consumption and improving water use efficiency has become essential for ensuring water security. This research aimed to identify the primary determinants of household water consumption in an Australian Indigenous community to develop evidence-based water demand management policies and strategies that might be implemented by the water service provider. A behavior change framework was applied to investigate the opportunity, ability, and motivational determinants affecting household water consumption and conservation in an Australian Indigenous community. The lack of water conservation knowledge and skills of high water users could be barriers to saving water. Low water users have positive attitudes towards water conservation and a higher level of awareness about their own water use. While there is a lack of a belief that water shortages will occur, low water users do have concerns of vulnerability to droughts, and that could be a driver for their sense of obligation to engage in water conservation practices. The research recommended communication messages and tools to address identified barriers to enabling positive changes to water use behaviors, which have wider applications in remote Australian Indigenous communities.
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Hammer, Michael P., Christopher M. Bice, Arkellah Hall, Adrienne Frears, Adam Watt, Nick S. Whiterod, Luciano B. Beheregaray, James O. Harris, and Brenton P. Zampatti. "Freshwater fish conservation in the face of critical water shortages in the southern Murray–Darling Basin, Australia." Marine and Freshwater Research 64, no. 9 (2013): 807. http://dx.doi.org/10.1071/mf12258.
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The lower reaches of the expansive Murray–Darling Basin, Australia, are a hotspot for freshwater biodiversity. The regional ecosystem, however, has been significantly altered by river regulation, including local and catchment-wide water abstraction. Freshwater fishes have suffered from the resultant altered flow regime, together with other threats including habitat degradation and alien species. Impacts reached a critical point (imminent species extinction) during a prolonged drought (1997–2010) that lead to broad-scale habitat loss and drying of refuges during 2007–2010, and urgent conservation measures were subsequently instigated for five threatened small-bodied fish species. A critical response phase included ad hoc interventions that were later incorporated within a broader, coordinated multi-agency program (i.e. the Drought Action Plan and Critical Fish Habitat projects). On-ground actions included local translocation, alien species control, in situ habitat maintenance (e.g. earthworks, environmental water delivery), fish rescues, artificial refuge establishment and captive breeding. Improved river flows signalled an initial phase of recovery in 2011–2012 that included reintroductions. The present paper aims to document the actions undertaken in the Lower Murray, and review successes and lessons from practical examples that will help guide and inform management responses to conserve fish in modified systems subjected to severe water decline.
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Kenway, S. J., G. M. Turner, S. Cook, and T. Baynes. "Water and energy futures for Melbourne: implications of land use, water use, and water supply strategy." Journal of Water and Climate Change 5, no. 2 (December 21, 2013): 163–75. http://dx.doi.org/10.2166/wcc.2013.188.
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This paper quantifies the effect of three policy levels on the water and energy futures of Melbourne, Australia. During a time of severe water shortages attributed to climate change, water strategies lacked consideration of energy consequences. Modeling, guided by urban metabolism theory, demonstrated that a compact urban form, reduced water consumption by 90 GL/a, compared with a sprawling city, and had greater water conservation impact than simulated demand management measures. Household water conservation, coupled with increased use of solar hot water systems, reduced grid energy use by some 30 PJ/a. Desalination, tripled water supply energy demand, growing to a total of 4.5 PJ/a, by 2045. While the increase is less than 1% of total Melbourne urban energy use, it contributes to a substantial increase in the energy bill for urban water provision. Importantly, the energy impact could be offset through demand management measures. Recommendations for the combined management of water and energy include improving energy characterization of the urban water cycle; impact-evaluation of regional plans; using total urban water and energy balances in analysis to provide context; and developing reporting mechanisms and indicators to help improve baseline data across the water and energy systems.
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Grimstad, Sidsel, and John Burgess. "Environmental sustainability and competitive advantage in a wine tourism micro-cluster." Management Research Review 37, no. 6 (May 13, 2014): 553–73. http://dx.doi.org/10.1108/mrr-01-2013-0019.
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Purpose – The paper aims to examine the competitive advantage of the environmental behaviour at a firm level and micro-cluster level, building the analysis on Harts model of natural resource-based view of the firm and by using Brown et al.'s framework for analysing contextual resources that would provide locational advantage based on environmental behaviour. The case study examines the drivers and the obstacles to environmental action and demonstrates how clustering has been important in progressing a sustainability agenda. Design/methodology/approach – A case study of a single wine tourism cluster in Australia is undertaken using mixed methods. Findings – The main drivers for environmental action are genuine concerns for the environment by the cluster participants, especially water conservation in the Australian context. Supporting this is the co-ordination of the Lovedale Chamber of Commerce which has promoted its “greening Lovedale” project as a source of regional identity and potential competitive advantage. The obstacles to action are those that are present when small firms dominate, a lack of resources and a lack of know how. Through clustering small businesses can share resources, access specialists and share knowledge. Research limitations/implications – A single cluster case study within the Australian and the wine tourism context confined to one point in time. Practical implications – The clustering of firms in agricultural regions offers the opportunity to achieve individual and collective benefits. Clustering participation can reduce costs, achieve scale economies and share knowledge. These advantages are relevant for environmental actions. In the context of weak or absent government actions and regulations over the environment, regional clusters can utilise the advantages of clustering to meet environmental goals. These in turn can contribute to regional identity and regional comparative advantage. These issues are addressed through the study of the Lovedale wine cluster in Australia. Originality/value – There are few studies of how clustered agricultural industries are addressing environmental challenges independently of central government directives or subsidies. Clustering enables small firms to participate in environmental programs despite being faced by resource and knowledge shortages.
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Moglia, M., K. S. Alexander, and A. Sharma. "Discussion of the enabling environments for decentralised water systems." Water Science and Technology 63, no. 10 (May 1, 2011): 2331–39. http://dx.doi.org/10.2166/wst.2011.443.
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Decentralised water supply systems are becoming increasingly affordable and commonplace in Australia and have the potential to alleviate urban water shortages and reduce pollution into natural receiving marine and freshwater streams. Learning processes are necessary to support the efficient implementation of decentralised systems. These processes reveal the complex socio-technical and institutional factors to be considered when developing an enabling environment supporting decentralised water and wastewater servicing solutions. Critical to the technological transition towards established decentralised systems is the ability to create strategic and adaptive capacity to promote learning and dialogue. Learning processes require institutional mechanisms to ensure the lessons are incorporated into the formulation of policy and regulation, through constructive involvement of key government institutions. Engagement of stakeholders is essential to the enabling environment. Collaborative learning environments using systems analysis with communities (social learning) and adaptive management techniques are useful in refining and applying scientists' and managers' knowledge (knowledge management).
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Li, Fuqin, David L. B. Jupp, Thomas Schroeder, Stephen Sagar, Joshua Sixsmith, and Passang Dorji. "Assessing an Atmospheric Correction Algorithm for Time Series of Satellite-Based Water-Leaving Reflectance Using Match-Up Sites in Australian Coastal Waters." Remote Sensing 13, no. 10 (May 14, 2021): 1927. http://dx.doi.org/10.3390/rs13101927.
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An atmospheric correction algorithm for medium-resolution satellite data over general water surfaces (open/coastal, estuarine and inland waters) has been assessed in Australian coastal waters. In situ measurements at four match-up sites were used with 21 Landsat 8 images acquired between 2014 and 2017. Three aerosol sources (AERONET, MODIS ocean aerosol and climatology) were used to test the impact of the selection of aerosol optical depth (AOD) and Ångström coefficient on the retrieved accuracy. The initial results showed that the satellite-derived water-leaving reflectance can have good agreement with the in situ measurements, provided that the sun glint is handled effectively. Although the AERONET aerosol data performed best, the contemporary satellite-derived aerosol information from MODIS or an aerosol climatology could also be as effective, and should be assessed with further in situ measurements. Two sun glint correction strategies were assessed for their ability to remove the glint bias. The most successful one used the average of two shortwave infrared (SWIR) bands to represent sun glint and subtracted it from each band. Using this sun glint correction method, the mean all-band error of the retrieved water-leaving reflectance at the Lucinda Jetty Coastal Observatory (LJCO) in north east Australia was close to 4% and unbiased over 14 acquisitions. A persistent bias in the other strategy was likely due to the sky radiance being non-uniform for the selected images. In regard to future options for an operational sun glint correction, the simple method may be sufficient for clear skies until a physically based method has been established.
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Williams, CK. "Water Physiology and Nutrition in Fluctuating Populations of Rattus-Colletti in Monsoonal Northern-Territory, Australia." Wildlife Research 14, no. 4 (1987): 443. http://dx.doi.org/10.1071/wr9870443.
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During wet and dry seasons and transitions of the monsoonal cycle, rates of water turnover and nutritional variables were measured on a population of Rattus colletti which fluctuated between extremes of high and low abundance. Rate of water turnover (RWT in millilitres per day) and body weight ( W, in kilograms) were related allometrically: RWT = aW*O.742 � 0.061, where a varied between seasons and sexes. Seasonal rates of water turnover were consistent with physiological adaptation in R. colletti to seasonal aridity. Rate of water turnover correlated with seasonal hydric regime, varying by a factor of 3.5 between dry and wet seasons. During the wet season, low body weight and lack of breeding seemed to be caused by flooding and its physical and social consequences. During dry season aridity the rats were short of food and water, but not in a dry season when rain fell and breeding ensued. Reproduction increased requirements for food and water in both sexes. Juveniles had relatively high requirements, and shortages appeared to retard growth. Very large populations resulted from prolific breeding after dry season rain had sustained high consumption of food and water on the riverine plains, the dry season habitat. Population decline resulted from very high wet season rainfall followed by a rainless dry season when food and water intakes were depressed, probably because the previous rainfall pattern reduced the availability of sedge corms, the dry season source of food and water. This climatic pattern recurred in the next wet and dry seasons, reinforcing the effects on R, colletti, which became rare for several years on both riverine systems studied.
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Yihdego, Yohannes, and John A. Webb. "Comparison of evaporation rate on open water bodies: energy balance estimate versus measured pan." Journal of Water and Climate Change 9, no. 1 (October 4, 2017): 101–11. http://dx.doi.org/10.2166/wcc.2017.139.
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Abstract Much attention has been paid to establish accurately open water evaporation since the lake itself is the largest consumer of water. The aim of this study is to assess the discrepancy in the measured (pan evaporation) and estimated (Penman) evaporation rate, seasonally, based on the results from a 37-year energy budget analysis of Lake Burrumbeet, Australia. The detailed analysis of meteorological data showed that evaporation is fully radiation driven and that the effect of wind is minimal. Sensitivity analysis shows that evaporation estimation is more sensitive to shortwave radiation followed by relative humidity. An increase or decrease of estimated shortwave radiation by 10% could result in an increase or decrease of estimated evaporation up to 18%. The Penman combination method is relatively the least sensitive to wind speed but could bring a significant effect on the lake level fluctuation since a 10% increase of wind speed increases the estimated evaporation by 2.3%. The current analysis highlights the relative roles of radiation, temperature, humidity, and wind speed in modulating the rate of evaporation from the lake surface, by employing an inter-monthly seasonal adjustment factor to the estimated evaporation in the lake water budget analysis, with implications for the inter-monthly variability and short-term trends assessment of water resource through various meteorological parameters.
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Okun, D. A. "Water reuse introduces the need to integrate both water supply and wastewater management at local and regulatory levels." Water Science and Technology 46, no. 6-7 (September 1, 2002): 273–80. http://dx.doi.org/10.2166/wst.2002.0689.
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Growing population and increasing urbanization is resulting in shortages of water supply for communities even in water-rich areas of the world. An approach to addressing this problem has been the introduction of wastewater reclamation and reuse for nonpotable purposes through dual distribution systems in municipalities in the United States on a significant scale in the 1970s and more recently in Japan and Australia. Many hundreds of communities, some very small and others very large, have adopted dual systems to add to their water resources and to reduce the burden of water pollution. Two issues deserve attention. The first is that the provision of water supply and its regulation by government is generally entirely separated from the provision of sewerage and wastewater treatment, so that the management of a reclaimed water service requires new arrangements both on the part of communities and of the government agencies that are concerned with the oversight of water supply and pollution control. The second issue is that the availability of new technology for treating waters drawn from polluted sources has led to proposals for purposefully using reclaimed water for potable purposes. The integration of water supply and wastewater disposal functions in professional organizations, such as IWA, is a useful step towards integrating water management in practice.
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Das, Sushil K., Amimul Ahsan, Md Habibur Rahman Bejoy Khan, Muhammad Atiq Ur Rehman Tariq, Nitin Muttil, and Anne W. M. Ng. "Impacts of Climate Alteration on the Hydrology of the Yarra River Catchment, Australia Using GCMs and SWAT Model." Water 14, no. 3 (February 1, 2022): 445. http://dx.doi.org/10.3390/w14030445.
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A rigorous evaluation of future hydro-climatic changes is necessary for developing climate adaptation strategies for a catchment. The integration of future climate projections from general circulation models (GCMs) in the simulations of a hydrologic model, such as the Soil and Water Assessment Tool (SWAT), is widely considered as one of the most dependable approaches to assess the impacts of climate alteration on hydrology. The main objective of this study was to assess the potential impacts of climate alteration on the hydrology of the Yarra River catchment in Victoria, Australia, using the SWAT model. The climate projections from five GCMs under two Representative Concentration Pathway (RCP) scenarios—RCP 4.5 and 8.5 for 2030 and 2050, respectively—were incorporated into the calibrated SWAT model for the analysis of future hydrologic behaviour against a baseline period of 1990–2008. The SWAT model performed well in its simulation of total streamflow, baseflow, and runoff, with Nash–Sutcliffe efficiency values of more than 0.75 for monthly calibration and validation. Based on the projections from the GCMs, the future rainfall and temperature are expected to decrease and increase, respectively, with the highest changes projected by the GFDL-ESM2M model under the RCP 8.5 scenario in 2050. These changes correspond to significant increases in annual evapotranspiration (8% to 46%) and decreases in other annual water cycle components, especially surface runoff (79% to 93%). Overall, the future climate projections indicate that the study area will become hotter, with less winter–spring (June to November) rainfall and with more water shortages within the catchment.
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R. Terry, Daniel, and Quynh Lê. "Social capital among migrating doctors: the “Bridge” over troubled water." Journal of Health Organization and Management 28, no. 3 (June 10, 2014): 315–26. http://dx.doi.org/10.1108/jhom-09-2012-0178.
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Purpose – The purpose of this paper is to examine the concept of social capital among International Medical Graduates (IMGs). It will specifically examine bridging social capital and greater intercultural communication which provides IMGs access to the wider community and plays a key role in cross-cultural adaptation and acculturation. Design/methodology/approach – A review of the literature. Findings – An Australian wide shortage of doctors has led to an increased reliance on the recruitment of IMGs. As IMGs migrate, they may encounter different meanings of illness, models of care and a number of social challenges. Nevertheless, greater cross-cultural adaptation and acculturation occurs through bridging social capital, where intercultural communication, new social networks and identity aids integration. This process produces more opportunities for economic capital growth and upward mobility than bonding social capital. Practical implications – Concerns regarding immigration, appropriate support and on-going examination processes have been expressed by IMGs in a number of studies and policy papers. However, there is very little insight into what contributes cross-cultural adaptation of IMGs. Originality/value – As IMGs migrate to not only a new country, but also a new health system and workplace they arrive with different cultural meanings of illness and models of care. These differences may be in contrast to the dominant western medical model, but often bring positive contributions to patient care in the new environment. In addition, improving bridging social capital provides IMGs access to the wider community and has been demonstrated to play a key role in cross-cultural adaptation and ultimately acculturation.
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Prata, A. J., I. F. Grant, R. P. Cechet, and G. F. Rutter. "Five years of shortwave radiation budget measurements at a continental land site in southeastern Australia." Journal of Geophysical Research: Atmospheres 103, no. D20 (October 1, 1998): 26093–106. http://dx.doi.org/10.1029/98jd02349.
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Hatt, B. E., A. Deletic, and T. D. Fletcher. "Stormwater reuse: designing biofiltration systems for reliable treatment." Water Science and Technology 55, no. 4 (February 1, 2007): 201–9. http://dx.doi.org/10.2166/wst.2007.110.
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Stormwater reuse is increasing in popularity as a technique for overcoming water shortages in urban Australia. However, technology for the reliable treatment of stormwater for reuse is still not fully developed. This paper presents the first steps in refining biofilters for stormwater reuse. Six different filter media were selected, to target specific stormwater pollutants, as well as support plant growth. They were tested in the laboratory, where the filters were dosed three times per week with semi-synthetic stormwater for five weeks. Pollutant removal performance was monitored, and revealed that all soil-based filters performed similarly (while sand filters behaved somewhat differently). All filters removed more than 80% of solids and greater than 90% of lead, copper, and zinc. Three filter types were able to remove some phosphorus (particularly in the top 30 cm of the media). Apart from sand, all filter media were net producers of nitrogen, leading to an important conclusion that non-vegetated, soil-based filters are not suitable for targeting nutrients. However, since heavy metals are the primary pollutant of concern with respect to stormwater reuse for irrigation (the most popular end-use), it was concluded that biofilters may be promising technologies for treatment of stormwater for reuse.
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Voloudakis, Andreas E., Sotirios A. Kosmas, Spyros Tsakas, Elias Eliopoulos, Michael Loukas, and Kyratso Kosmidou. "Expression of selected drought-related genes and physiological response of Greek cotton varieties." Functional Plant Biology 29, no. 10 (2002): 1237. http://dx.doi.org/10.1071/pp01253.
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Drought-tolerant cotton varieties are very important for Greece and throughout the world. Four Greek cotton varieties (Zeta 2, Zeta 5, Korina and Eva) and an Australian variety (Siokra L23) were subjected to three water-stress levels (0.0, –0.1 and –0.3 MPa). Morphological and physiological parameters studied were plant height, total leaf area, shoot, root and total plant fresh and dry weights, stomatal resistance (SR), water potential (Ψ w), and relative water content. Siokra L23 was confirmed to be the most drought-tolerant variety based on its high SR and Ψ w , it's having the smallest total leaf area, and expression of drought-tolerance-related genes. The Greek cotton varieties were ranked from most to least drought tolerant as follows: Eva, Korina, Zeta 2, Zeta 5.Molecular responses of the cotton varieties were studied by investigating the expression of five drought-tolerance-related genes, namely, trehalose-6-P synthase, heat-shock protein calmodulin-binding homolog, late embryogenesis abundant (Lea) proteins 14A and 5D, and NAD(P)H oxidase. Reverse transcription–polymerase chain reaction was performed utilizing total RNA samples isolated after a 4-d drought treatment (i.e. at the end of the stress period). Heat-shock protein calmodulin-binding homolog was induced by water stress in drought-tolerant varieties (Eva and Siokra L23) and Zeta 2. This correlation between physiological and molecular data for this gene allows it to be used in cotton breeding programs. Trehalose-6-P synthase and NAD(P)H oxidase genes were not expressed in almost all varieties and treatments. In contrast, the Lea genes showed, with minor exceptions, expression that was independent of variety and treatment. Eva and Korina varieties should be used under conditions of water shortage, whereas Zeta varieties provide a significant advantage to the grower when planted under conditions of high water availability.
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Hartigan, Joshua, Shev MacNamara, Lance M. Leslie, and Milton Speer. "Attribution and Prediction of Precipitation and Temperature Trends within the Sydney Catchment Using Machine Learning." Climate 8, no. 10 (October 20, 2020): 120. http://dx.doi.org/10.3390/cli8100120.
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Droughts in southeastern Australia can profoundly affect the water supply to Sydney, Australia’s largest city. Increasing population, a warming climate, land surface changes and expanded agricultural use increase water demand and reduce catchment runoff. Studying Sydney’s water supply is necessary to manage water resources and lower the risk of severe water shortages. This study aims at understanding Sydney’s water supply by analysing precipitation and temperature trends across the catchment. A decreasing trend in annual precipitation was found across the Sydney catchment area. Annual precipitation also is significantly less variable, due to fewer years above the 80th percentile. These trends result from significant reductions in precipitation during spring and autumn, especially over the last 20 years. Wavelet analysis was applied to assess how the influence of climate drivers has changed over time. Attribute selection was carried out using linear regression and machine learning techniques, including random forests and support vector regression. Drivers of annual precipitation included Niño3.4, Southern Annular Mode (SAM) and DMI, and measures of global warming such as the Tasman Sea sea surface temperature anomalies. The support vector regression model with a polynomial kernel achieved correlations of 0.921 and a skill score compared to climatology of 0.721. The linear regression model also performed well with a correlation of 0.815 and skill score of 0.567, highlighting the importance of considering both linear and non-linear methods when developing statistical models. Models were also developed on autumn and winter precipitation but performed worse than annual precipitation on prediction. For example, the best performing model on autumn precipitation, which accounts for approximately one quarter of annual precipitation, achieved an RMSE of 418.036 mm2 on the testing data, while annual precipitation achieved an RMSE of 613.704 mm2. However, the seasonal models provided valuable insights into whether the season would be wet or dry compared to the climatology.
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Zhang, Xinzhong, Yu Li, Qin Han, and Yuxin Zhang. "Timescale-dependent responses of hydrological changes from global closed basins since the last glacial maximum." Progress in Physical Geography: Earth and Environment 46, no. 2 (December 7, 2021): 201–16. http://dx.doi.org/10.1177/03091333211051939.
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Water shortage has plagued the social development and human well-being of global closed basins. However, the hydroclimate research on different time scales in these regions remains inadequate at a global scale. In this paper, the hydrological responses from global closed basins to millennial-scale and centennial-scale cold/warm events since the Last Glacial Maximum were explored. Closed-basin lake records indicate that the westerlies-dominated closed basins are generally wetter during cold events than the corresponding warm ones on the millennial and centennial scales. In contrast, the monsoon-influenced closed basins prevail wetter climates during warm events. According to the hydroclimate simulations, precipitation seasonality plays a significant role in causing above spatial–temporal patterns. There is more winter rainfall in westerlies-dominated closed basins during cold events in the Last Glacial Maximum and Little Ice Age and more summer rainfall in monsoon-influenced closed basins during warm events in the mid-Holocene and Medieval Climate Anomaly. Under modern and future global warming, the hydroclimate changes in global closed basins show more regional differentiation, resulting in wetter mid-latitude Asian and low-latitude African closed basins but drier southwest North American and Australian closed basins.
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Joshi, Rakesh Chandra, Dongryeol Ryu, Gary J. Sheridan, and Patrick N. J. Lane. "Modeling Vegetation Water Stress over the Forest from Space: Temperature Vegetation Water Stress Index (TVWSI)." Remote Sensing 13, no. 22 (November 17, 2021): 4635. http://dx.doi.org/10.3390/rs13224635.
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The conventional Land Surface Temperature (LST)–Normalized Difference Vegetation Index (NDVI) trapezoid model has been widely used to retrieve vegetation water stress. However, it has two inherent limitations: (1) its complex and computationally intensive parameterization for multi-temporal observations and (2) deficiency in canopy water content information. We tested the hypothesis that an improved water stress index could be constructed by the representation of canopy water content information to the LST–NDVI trapezoid model. Therefore, this study proposes a new index that combines three indicators associated with vegetation water stress: canopy temperature through LST, canopy water content through Surface Water Content Index (SWCI), and canopy fractional cover through NDVI in one temporally transferrable index. Firstly, a new optical space of SWCI–NDVI was conceptualized based on the linear physical relationship between shortwave infrared (SWIR) and soil moisture. Secondly, the SWCI–NDVI feature space was parameterized, and an index d(SWCI, NDVI) was computed based on the distribution of the observations in the SWCI–NDVI spectral space. Finally, standardized LST (LST/long term mean of LST) was combined to d(SWCI, NDVI) to give a new water stress index, Temperature Vegetation Water Stress Index (TVWSI). The modeled soil moisture from the Australian Water Resource Assessment—Landscape (AWRA-L) and Soil Water Fraction (SWF) from four FLUXNET sites across Victoria and New South Wales were used to evaluate TVWSI. The index TVWSI exhibited a high correlation with AWRA-L soil moisture (R2 of 0.71 with p < 0.001) and the ground-based SWF (R2 of 0.25–0.51 with p < 0.001). TVWSI predicted soil moisture more accurately with RMSE of 21.82 mm (AWRA-L) and 0.02–0.04 (SWF) compared to the RMSE ranging 28.98–36.68 mm (AWRA-L) and 0.03–0.05 (SWF) were obtained for some widely used water stress indices. The TVWSI could also be a useful input parameter for other environmental models.
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Huang, Yi, Steven T. Siems, Michael J. Manton, Luke B. Hande, and John M. Haynes. "The Structure of Low-Altitude Clouds over the Southern Ocean as Seen by CloudSat." Journal of Climate 25, no. 7 (March 28, 2012): 2535–46. http://dx.doi.org/10.1175/jcli-d-11-00131.1.
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Abstract A climatology of the structure of the low-altitude cloud field (tops below 4 km) over the Southern Ocean (40°–65°S) in the vicinity of Australia (100°–160°E) has been constructed with CloudSat products for liquid water and ice water clouds. Averaging over longitude and time, CloudSat produces a roughly uniform cloud field between heights of approximately 750 and 2250 m across the extent of the domain for both winter and summer. This cloud field makes a transition from consisting primarily of liquid water at the lower latitudes to ice water at the higher latitudes. This transition is primarily driven by the gradient in the temperature, which is commonly between 0° and −20°C, rather than by direct physical observation. The uniform lower boundary is a consequence of the CloudSat cloud detection algorithm being unable to reliably separate radar returns because of the bright surface versus returns due to clouds, in the lowest four range bins above the surface. This is potentially very problematic over the Southern Ocean where the depth of the boundary layer has been observed to be as shallow as 500 m. Cloud fields inferred from upper-air soundings at Macquarie Island (54.62°S, 158.85°E) similarly suggest that the peak frequency lies between 260 and 500 m for both summer and winter. No immediate explanation is available for the uniformity of the cloud-top boundary. This lack of a strong seasonal cycle is, perhaps, remarkable given the large seasonal cycles in both the shortwave (SW) radiative forcing experienced and the cloud condensation nuclei (CCN) concentration over the Southern Ocean.
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Ritman, Mathilde E. H., and Linden C. Ashcroft. "Revisiting the 1888 Centennial Drought." Proceedings of the Royal Society of Victoria 132, no. 2 (2020): 49. http://dx.doi.org/10.1071/rs20004.
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Droughts are a key feature of Australia’s climate and can lead to water shortages, crop failure and economic instability. Historical droughts are an important source of information to better understand recent droughts and how they might be managed. However, the majority of studies into Australian drought only consider dry periods in the 20th and 21st centuries. Here, a newly developed gridded rainfall dataset from the Bureau of Meteorology and a network of historical rainfall stations are used to re-examine the short but sharp Centennial Drought of 1888. The Centennial Drought is explored on a monthly scale, highlighting key periods of rainfall deficiency, and identifying the impacts of relevant atmospheric circulation patterns. The most significant rainfall declines occur in autumn and spring and are likely to be the result of an El Niño event, a positive Sub-Tropical Ridge intensity anomaly, and seasonal fluctuations of the Southern Annular Mode. Comparing the Centennial Drought to other short droughts of 1914–15, 1982–83 and 2017~ indicates that the magnitude of the rainfall deficiencies and widespread spatial extent are comparable, placing the Centennial Drought alongside some of the most severe short droughts in Australia’s colonial climate history.
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Kacenelenbogen, Meloë S., Mark A. Vaughan, Jens Redemann, Stuart A. Young, Zhaoyan Liu, Yongxiang Hu, Ali H. Omar, et al. "Estimations of global shortwave direct aerosol radiative effects above opaque water clouds using a combination of A-Train satellite sensors." Atmospheric Chemistry and Physics 19, no. 7 (April 12, 2019): 4933–62. http://dx.doi.org/10.5194/acp-19-4933-2019.
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Abstract. All-sky direct aerosol radiative effects (DARE) play a significant yet still uncertain role in climate. This is partly due to poorly quantified radiative properties of aerosol above clouds (AAC). We compute global estimates of shortwave top-of-atmosphere DARE over opaque water clouds (OWCs), DAREOWC, using observation-based aerosol and cloud radiative properties from a combination of A-Train satellite sensors and a radiative transfer model. There are three major differences between our DAREOWC calculations and previous studies: (1) we use the depolarization ratio method (DR) on CALIOP (Cloud–Aerosol Lidar with Orthogonal Polarization) Level 1 measurements to compute the AAC frequencies of occurrence and the AAC aerosol optical depths (AODs), thus introducing fewer uncertainties compared to using the CALIOP standard product; (2) we apply our calculations globally, instead of focusing exclusively on regional AAC “hotspots” such as the southeast Atlantic; and (3) instead of the traditional look-up table approach, we use a combination of satellite-based sensors to obtain AAC intensive radiative properties. Our results agree with previous findings on the dominant locations of AAC (south and northeast Pacific, tropical and southeast Atlantic, northern Indian Ocean and northwest Pacific), the season of maximum occurrence and aerosol optical depths (a majority in the 0.01–0.02 range and that can exceed 0.2 at 532 nm) across the globe. We find positive averages of global seasonal DAREOWC between 0.13 and 0.26 W m−2 (i.e., a warming effect on climate). Regional seasonal DAREOWC values range from −0.06 W m−2 in the Indian Ocean offshore from western Australia (in March–April–May) to 2.87 W m−2 in the southeast Atlantic (in September–October–November). High positive values are usually paired with high aerosol optical depths (>0.1) and low single scattering albedos (<0.94), representative of, for example, biomass burning aerosols. Because we use different spatial domains, temporal periods, satellite sensors, detection methods and/or associated uncertainties, the DAREOWC estimates in this study are not directly comparable to previous peer-reviewed results. Despite these differences, we emphasize that the DAREOWC estimates derived in this study are generally higher than previously reported. The primary reasons for our higher estimates are (i) the possible underestimate of the number of dust-dominated AAC cases in our study; (ii) our use of Level 1 CALIOP products (instead of CALIOP Level 2 products in previous studies) for the detection and quantification of AAC aerosol optical depths, which leads to larger estimates of AOD above OWC; and (iii) our use of gridded 4∘×5∘ seasonal means of aerosol and cloud properties in our DAREOWC calculations instead of simultaneously derived aerosol and cloud properties from a combination of A-Train satellite sensors. Each of these areas is explored in depth with detailed discussions that explain both the rationale for our specific approach and the subsequent ramifications for our DARE calculations.
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Fiddes, Sonya L., Alain Protat, Marc D. Mallet, Simon P. Alexander, and Matthew T. Woodhouse. "Southern Ocean cloud and shortwave radiation biases in a nudged climate model simulation: does the model ever get it right?" Atmospheric Chemistry and Physics 22, no. 22 (November 17, 2022): 14603–30. http://dx.doi.org/10.5194/acp-22-14603-2022.
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Abstract. The Southern Ocean radiative bias continues to impact climate and weather models, including the Australian Community Climate and Earth System Simulator (ACCESS). The radiative bias, characterised by too much shortwave radiation reaching the surface, is attributed to the incorrect simulation of cloud properties, including frequency and phase. To identify cloud regimes important to the Southern Ocean, we use k-means cloud histogram clustering, applied to a satellite product and then fitted to nudged simulations of the latest-generation ACCESS atmosphere model. We identify instances when the model correctly or incorrectly simulates the same cloud type as the satellite product for any point in time or space. We then evaluate the cloud and radiation biases in these instances. We find that when the ACCESS model correctly simulates the cloud type, cloud property and radiation biases of equivalent, or in some cases greater, magnitude remain compared to when cloud types are incorrectly simulated. Furthermore, we find that even when radiative biases appear small on average, cloud property biases, such as liquid or ice water paths or cloud fractions, remain large. Our results suggest that simply getting the right cloud type (or the cloud macrophysics) is not enough to reduce the Southern Ocean radiative bias. Furthermore, in instances where the radiative bias is small, it may be so for the wrong reasons. Considerable effort is still required to improve cloud microphysics, with a particular focus on cloud phase.
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Morrison, Anthony E., Steven T. Siems, and Michael J. Manton. "A Three-Year Climatology of Cloud-Top Phase over the Southern Ocean and North Pacific." Journal of Climate 24, no. 9 (May 1, 2011): 2405–18. http://dx.doi.org/10.1175/2010jcli3842.1.
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Abstract Moderate Resolution Imaging Spectroradiometer (MODIS) Level 2 observations from the Terra satellite are used to create a 3-yr climatology of cloud-top phase over a section of the Southern Ocean (south of Australia) and the North Pacific Ocean. The intent is to highlight the extensive presence of supercooled liquid water over the Southern Ocean region, particularly during summer. The phase of such clouds directly affects the absorbed shortwave radiation, which has recently been found to be “poorly simulated in both state-of-the-art reanalysis and coupled global climate models” (Trenberth and Fasullo). The climatology finds that supercooled liquid water is present year-round in the low-altitude clouds across this section of the Southern Ocean. Further, the MODIS cloud phase algorithm identifies very few glaciated cloud tops at temperatures above −20°C, rather inferring a large portion of “uncertain” cloud tops. Between 50° and 60°S during the summer, the albedo effect is compounded by a seasonal reduction in high-level cirrus. This is in direct contrast to the Bering Sea and Gulf of Alaska. Here MODIS finds a higher likelihood of observing warm liquid water clouds during summer and a reduction in the relative frequency of cloud tops within the 0° to −20°C temperature range. As the MODIS cloud phase product has limited ability to confidently identify cloud-top phase between −5° and −25°C, future research should include observations from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and other space-based sensors to help with the classification within this temperature range. Further, multiregion in situ verification of any remotely sensed observations is vital to further understanding the cloud phase processes.
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Lindawati, Lindawati. "Urban pollution control strategy: SBR technology to treat agricultural waste from pig farm in Indonesia." Sains & Teknologi 2, no. 2 (October 17, 2019): 21. http://dx.doi.org/10.24123/jst.v2i2.2250.
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Reduction of food rations and shortages is one of the impacts of the increasing human population. Food sector industries then try to cope with the fast growing number of customers. Agribusiness sector gains its popularity in these recent years, including pig farm. The increase trend of animal farming industry is likely to bring increasing pollution problem unless effective treatment methods are used. The main problems related to the pig farm include odor nuisance and pig manure disposal. The existing land application of piggery wastewater is the traditional way to discharge the wastewater. This may yield in land and water contamination, due to the accumulation of unused nutrients by crop plant. A case study of a large commercial pig farm from Australia is proposed to apply in smaller scale in Indonesia. Operational strategies for the small-scale SBR (Sequencing Batch Reactor) treating piggery effluent were developed based on lab-scale experiments. Due to SBR characteristics, which are money-saving and space-saving, it is very suitable to be applied in urban area. An economic evaluation was made of various process options. The cost estimation showed that SBR is a cost effective process, allowing operational batches to be adjusted to reduce unnecessary aeration cost. A reduction in the aeration cost was achieved by shortening the batch time from 24-h to 8-h. A comparison of three different SBR options showed that smaller size reactors could be more flexible and cost effective when compared with the larger ones.
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Principe, J. A., and W. Takeuchi. "ASSESSMENT OF SOLAR PV POWER POTENTIAL IN THE ASIA PACIFIC REGION WITH REMOTE SENSING CONSIDERING THE EFFECTS OF HIGH TEMPERATURE, DUST AND SNOW." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W19 (December 23, 2019): 339–46. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w19-339-2019.
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Abstract. The last half century has witnessed the increasing trend of renewable energy utilization with solar photovoltaic (PV) systems as one of the most popular option. Solar PV continues to supplement the main grid in powering both commercial establishments (mainly for reduced electricity expense) as well as residential houses in isolated areas (for basic energy requirement such as for lighting purposes). The objective of this study is to assess the available solar PV power (PPV) potential considering the effects of high temperature, dust and snow in the Asia Pacific region. The PPV potential was estimated considering the effects of the said meteorological parameters using several satellite data including shortwave radiation from Advanced Himawari Imager 8 (AHI8), MOD04 aerosol data from Moderate Resolution Imaging Spectroradiometer (MODIS), precipitation rate from Global Satellite Mapping of Precipitation (GSMaP), air temperature from NCEP/DOE AMIP-II Reanalysis-2 data, and snow water equivalent (SWE) from Microwave Scanning Radiometer for the Earth Observing System (AMSR-E). The model is validated by comparing its outputs with the measured PV power from two solar PV installations in Bangkok, Thailand and Perth, Australia. Results show that maximum PPV is estimated at 2.5 GW (cell efficiency of 17.47%) for the region with the maximum decrease in PPV estimated to be about < 2%, 22% and 100% due to high temperature (temperature coefficient of power = 0.47%/K), dust and snow, respectively. Moreover, areas in India and Northern China were observed to experience the effects of both dust and temperature during March-April-May (MAM) season. Meanwhile, countries located in the higher latitudes were severely affected by snow while Australia by high temperature during Dec-Jan-Feb (DJF) season. The model has a mean percentage prediction error (PPE) range of 5% to18% and 7% to 23% in seasonal and monthly estimations, respectively. Outputs from this study can be used by stakeholders of solar PV in planning for small-scale or large-scale solar PV projects in the solar rich region of Asia Pacific.
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Holechek, Jerry L. "Global trends in population, energy use and climate: implications for policy development, rangeland management and rangeland users." Rangeland Journal 35, no. 2 (2013): 117. http://dx.doi.org/10.1071/rj12077.
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Increasing world human population, declining reserves of cheaply extracted fossil fuels, scarcity of supplies of fresh water and climatic instability will put tremendous pressure on world rangelands as the 21st century progresses. It is expected that the human population of the world will increase by 40% by 2050 but fossil fuel and reserves of fresh water will be drastically reduced. Avoiding food shortages and famine could be a major world challenge within the next 10 years. Under these conditions, major changes in policies relating to economic growth and use of natural resources seem essential. Stabilisation of the human population, development of clean and renewable energy, enhanced supplies of water and its quality, increased livestock production, and changed land-use policies, that minimise agricultural land losses to development and fragmentation, will all be needed to avoid declining living conditions at the global level. The health and productivity of rangelands will need to receive much more emphasis as they are a primary source of vital ecosystem services and products essential to human life. Changes in tax policies by developed, affluent countries, such as the United States, Australia and Canada, are needed that emphasise saving and conservation as opposed to excessive material consumption and land development. Extreme levels of debt and chronic deficits in trade by the United States and European Union countries need to be moderated to avoid a devastating collision of debt, depletion of natural resources, and environmental degradation. Over the next 10 years, livestock producers of the rangelands will benefit from a major increase in demand and prices for meat. Rapidly increasing demand for meat in China and other Asian countries is driving this trend. Rangeland managers, however, will also likely encounter greater climatic, financial, biological and political risks. Higher interest rates, higher production costs and higher annual variability in forage resources are major challenges that will confront rangeland managers in the years ahead. Under these conditions, a low risk approach to livestock production from rangelands is recommended that involves conservative stocking, use of highly adapted livestock, and application of behavioural knowledge of livestock to efficiently use forage resources.
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Auger, J., F. Palma, I. Pérez, and M. Esterio. "First Report of Neofusicoccum australe (Botryosphaeria australis), as a Branch Dieback Pathogen of Avocado Trees in Chile." Plant Disease 97, no. 6 (June 2013): 842. http://dx.doi.org/10.1094/pdis-10-12-0980-pdn.
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Since 2007, Chilean avocado (Persea americana Mill.) orchards have been exposed to several abiotic stress conditions, namely frost damage and drought, due to three consecutive seasons of cold winters and shortage of irrigation water. At the same time, a severe disease resulting in tree dieback of cv. Hass, specifically, was observed in north-central Chile. Symptomatic trees exhibited abundant dead twigs in the tree canopy, and wilted leaves remained attached to the twigs in autumn. Closer inspection revealed reddish-brown necrotic lesions on the bark of the dead twigs, which girdled these symptomatic branches. When the bark was removed, the wood below appeared dark brown, in contrast to the yellowish-green coloring of healthy. The fungus was also consistently isolated from rotted fruit. A Neofusicoccum sp. with a yellow colony was consistently isolated from the necrotic lesions on PDA and incubated at room temperature for 3 days. Conidia produced in black pycnidia growing on 2% water agar with sterilized pine needles were smooth, unicellular, hyaline, and with granular contents. One or two septa developed at germination, but rarely before. The average length of the conidia was 27.0 ± 0.9 μm, with a length/width ratio of 3.9 ± 0.2 μm. Based on culture and conidial morphology, the isolates were putatively identified as Neofusicoccum luteum (1). DNA sequence analysis of the rDNA internal transcribed spacer (ITS) region was conducted for four representative isolates using primers ITS1 and ITS4 (4). The sequence analysis of ITS region of kiwifruit isolate H1M4 (Accession No. KC330230) reveled 100% nucleotide identity to N. australe (FJ157187 to FJ157192) (3). Pathogenicity tests were conducted with stem inoculations of 2-year-old cv. Hass plants grow in plastic containers in a sand/lime/peat mixture. For each inoculated plant (n = 8), a 7-mm-diameter agar plug from the margin of a 3-day culture was used as inoculum after wounding the stem to the depth to 7 mm with a cork borer. Negative control (n = 8) were wounded and then ‘mock-inoculated’ with sterile agar plugs. The inoculation sites were wrapped with Parafilm. All plants were kept in a greenhouse. After 5 months, all inoculated plants showed bark cankers and necrotic lesions beneath the bark, which were 5.2 cm long (n = 8). No symptoms developed on the control plants. N. australe was recovered from the margin of the necrosis lesion of every inoculated plant, thus fulfilling Koch's postulates and confirming its pathogenicity. Botryosphaeraceae spp. are the commonly reported to have ability to survive endophytically in their host, causing disease only when the host is exposed to a stress condition (2). To our knowledge, this is the first report of N. australe as a pathogen of avocado in Chile. The fungal isolates (PaHass No. 1 to 4) were deposited in the Laboratorio de Fitopatología Frutal y Molecular, Departamento de Sanidad Vegetal, Facultad de Ciencias Agronómicas de la Universidad de Chile. References: (1) A. J. L. Phillips. http://www.crem.fct.unl.pt/botryosphaeria_site/ Accessed November 20, 2011. (2) B. Slippers and M. J. Wingfield. Fungal Biol. Rev. 21:90, 2007. (3) B. Slippers et al. Mycologia 96:1030, 2004. (4) White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.
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Protat, A., J. Delanoë, E. J. O’Connor, and T. S. L’Ecuyer. "The Evaluation of CloudSat and CALIPSO Ice Microphysical Products Using Ground-Based Cloud Radar and Lidar Observations." Journal of Atmospheric and Oceanic Technology 27, no. 5 (May 1, 2010): 793–810. http://dx.doi.org/10.1175/2009jtecha1397.1.
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Abstract In this paper, the statistical properties of tropical ice clouds (ice water content, visible extinction, effective radius, and total number concentration) derived from 3 yr of ground-based radar–lidar retrievals from the U.S. Department of Energy Atmospheric Radiation Measurement Climate Research Facility in Darwin, Australia, are compared with the same properties derived using the official CloudSat microphysical retrieval methods and from a simpler statistical method using radar reflectivity and air temperature. It is shown that the two official CloudSat microphysical products (2B-CWC-RO and 2B-CWC-RVOD) are statistically virtually identical. The comparison with the ground-based radar–lidar retrievals shows that all satellite methods produce ice water contents and extinctions in a much narrower range than the ground-based method and overestimate the mean vertical profiles of microphysical parameters below 10-km height by over a factor of 2. Better agreements are obtained above 10-km height. Ways to improve these estimates are suggested in this study. Effective radii retrievals from the standard CloudSat algorithms are characterized by a large positive bias of 8–12 μm. A sensitivity test shows that in response to such a bias the cloud longwave forcing is increased from 44.6 to 46.9 W m−2 (implying an error of about 5%), whereas the negative cloud shortwave forcing is increased from −81.6 to −82.8 W m−2. Further analysis reveals that these modest effects (although not insignificant) can be much larger for optically thick clouds. The statistical method using CloudSat reflectivities and air temperature was found to produce inaccurate mean vertical profiles and probability distribution functions of effective radius. This study also shows that the retrieval of the total number concentration needs to be improved in the official CloudSat microphysical methods prior to a quantitative use for the characterization of tropical ice clouds. Finally, the statistical relationship used to produce ice water content from extinction and air temperature obtained by the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite is evaluated for tropical ice clouds. It is suggested that the CALIPSO ice water content retrieval is robust for tropical ice clouds, but that the temperature dependence of the statistical relationship used should be slightly refined to better reproduce the radar–lidar retrievals.
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Xu, X., D. Yang, and M. Sivapalan. "Assessing the impact of climate variability on catchment water balance and vegetation cover." Hydrology and Earth System Sciences 16, no. 1 (January 6, 2012): 43–58. http://dx.doi.org/10.5194/hess-16-43-2012.
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Abstract. Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected by fPAR) among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total, surface and subsurface runoff) and on vegetation cover (including total, woody and non-woody vegetation cover). Based on the results of statistical analysis, we conclude that annual runoff (R), evapotranspiration (E) and runoff coefficient (R/P) increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Control of water available on annual evapotranspiration in non-woody dominated catchments is relatively stronger compared to woody dominated ones. The ratio of subsurface runoff to total runoff (Rg/R) also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P) in current year is the most important factor affecting the change in annual total runoff (R), surface runoff (Rs) and subsurface runoff (Rg). The significance of other controlling factors is in the order of annual precipitation in previous years (P−1 and P−2), which represents the net effect of soil moisture and annual mean temperature (T) in current year. Change of P by +1% causes a +3.35% change of R, a +3.47% change of Rs and a +2.89% change of Rg, on average. Results of elasticity analysis on the maximum monthly vegetation cover indicate that incoming shortwave radiation during the growing season (Rsd,grow) is the most important factor affecting the change in vegetation cover. Change of Rsd,grow by +1% produces a −1.08% change of total vegetation cover (Ft) on average. The significance of other causative factors is in the order of precipitation during growing season, mean temperature during growing season and precipitation during non-growing season. Growing season precipitation is more significant than non-growing season precipitation to non-woody vegetation cover, but both have equivalent effects to woody vegetation cover.
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Bigg, E. Keith. "Trends in rainfall associated with sources of air pollution." Environmental Chemistry 5, no. 3 (2008): 184. http://dx.doi.org/10.1071/en07086.
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Environmental context. Decreasing trends in rainfall over large areas of eastern and south-western Australia have resulted in critical water shortages. Three reasons have been suggested. The first is a change in atmospheric circulation as a result of greenhouse gas forcing. The second is that changes in land usage have affected surface moisture, albedo and cloud formation. Another, the subject of this study, is that airborne particulates associated with urban areas have acted to decrease the mean efficiency of rainfall, the growth of urban areas thereby causing an underlying decreasing trend in rainfall. Abstract. Trends in rainfall in the 35 years 1970–2004 have been calculated for all 350 available rainfall stations having sufficiently complete records that lie between latitudes 26–30°S and longitudes 150–154°E. The area contains two major urban centers, Brisbane with a rapidly growing population approaching two million and the Gold Coast with a population of ~500 000. Statistically highly significant negative trends were found in the vicinity of Brisbane, with decreases exceeding 40% of mean daily rainfall in the 35 years, and in a smaller area inland from the Gold Coast. The spatial distribution of trends was consistent with aerosol production from human activities, the prevailing winds and losses due to the topography. A previously published observation using satellite data showed that cloud properties were affected by urban aerosols in a way that is likely to reduce precipitation. The results of this study reinforce the suggestion made then that monitoring of aerosol concentrations and properties and in-situ observations of rain formation processes in the area should be undertaken as a matter of urgency.
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Xu, X., D. Yang, and M. Sivapalan. "Assessing the impact of climate variability on catchment water balance and vegetation cover." Hydrology and Earth System Sciences Discussions 8, no. 3 (June 29, 2011): 6291–329. http://dx.doi.org/10.5194/hessd-8-6291-2011.
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Abstract. Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability (e.g., precipitation and temperature) on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected in fPAR) among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total runoff, surface and subsurface runoff) and on vegetation cover (including total, woody and non-woody vegetation cover). Based on the results of statistical analysis, we conclude that annual runoff (R), evapotranspiration (E) and runoff coefficient (R/P) all increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Annual evapotranspiration (E) is mainly controlled by water availability rather than energy availability for catchments in relatively dry climates in which non-woody vegetation is dominant. The ratio of subsurface runoff to total runoff (Rg/R) also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P) in the current year is the most important factor affecting the change in annual total runoff (R), surface runoff (Rs) and subsurface runoff (Rg). The significance of other controlling factors is in the order of the annual precipitation in the previous year (P−1 and P−2), which represent the net effect of soil moisture, and the annual mean temperature (T) in the current year. Change of P by +1 % causes a +3.35 % change of R, a +3.47 % change of Rs and a +2.89 % change of Rg, on average. Likewise a change of temperature of +1° causes a −0.05 % change of R, a −0.07 % change of Rs and a −0.10 % change of Rg, on average. Results of elasticity analysis on the maximum monthly vegetation cover indicate that incoming shortwave radiation during the growing season (Rsd,grow) is the most important factor affecting the change in vegetation cover. Change of Rsd,grow by +1 % produces a −1.08 % change of total vegetation cover (Ft) on average. The significance of other causative factors is in the order of the precipitation during growing season, mean temperature during growing season and precipitation during non-growing season. The growing season precipitation is more significant than the non-growing season precipitation to non-woody vegetation cover, but the both have equivalent effects to woody vegetation cover.
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van Oorschot, Fransje, Ruud J. van der Ent, Markus Hrachowitz, and Andrea Alessandri. "Climate-controlled root zone parameters show potential to improve water flux simulations by land surface models." Earth System Dynamics 12, no. 2 (June 21, 2021): 725–43. http://dx.doi.org/10.5194/esd-12-725-2021.
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Abstract. The root zone storage capacity (Sr) is the maximum volume of water in the subsurface that can potentially be accessed by vegetation for transpiration. It influences the seasonality of transpiration as well as fast and slow runoff processes. Many studies have shown that Sr is heterogeneous as controlled by local climate conditions, which affect vegetation strategies in sizing their root system able to support plant growth and to prevent water shortages. Root zone parameterization in most land surface models does not account for this climate control on root development and is based on lookup tables that prescribe the same root zone parameters worldwide for each vegetation class. These lookup tables are obtained from measurements of rooting structure that are scarce and hardly representative of the ecosystem scale. The objective of this research is to quantify and evaluate the effects of a climate-controlled representation of Sr on the water fluxes modeled by the Hydrology Tiled ECMWF Scheme for Surface Exchanges over Land (HTESSEL) land surface model. Climate-controlled Sr is estimated here with the “memory method” (MM) in which Sr is derived from the vegetation's memory of past root zone water storage deficits. Sr,MM is estimated for 15 river catchments over Australia across three contrasting climate regions: tropical, temperate and Mediterranean. Suitable representations of Sr,MM are implemented in an improved version of HTESSEL (Moisture Depth – MD) by accordingly modifying the soil depths to obtain a model Sr,MD that matches Sr,MM in the 15 catchments. In the control version of HTESSEL (CTR), Sr,CTR is larger than Sr,MM in 14 out of 15 catchments. Furthermore, the variability among the individual catchments of Sr,MM (117–722 mm) is considerably larger than of Sr,CTR (491–725 mm). The climate-controlled representation of Sr in the MD version results in a significant and consistent improvement of the modeled monthly seasonal climatology (1975–2010) and interannual anomalies of river discharge compared with observations. However, the effects on biases in long-term annual mean river discharge are small and mixed. The modeled monthly seasonal climatology of the catchment discharge improved in MD compared to CTR: the correlation with observations increased significantly from 0.84 to 0.90 in tropical catchments, from 0.74 to 0.86 in temperate catchments and from 0.86 to 0.96 in Mediterranean catchments. Correspondingly, the correlations of the interannual discharge anomalies improve significantly in MD from 0.74 to 0.78 in tropical catchments, from 0.80 to 0.85 in temperate catchments and from 0.71 to 0.79 in Mediterranean catchments. The results indicate that the use of climate-controlled Sr,MM can significantly improve the timing of modeled discharge and, by extension, also evaporation fluxes in land surface models. On the other hand, the method has not been shown to significantly reduce long-term climatological model biases over the catchments considered for this study.
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Mace, Gerald G., and Alain Protat. "Clouds over the Southern Ocean as Observed from the R/V Investigator during CAPRICORN. Part II: The Properties of Nonprecipitating Stratocumulus." Journal of Applied Meteorology and Climatology 57, no. 8 (August 2018): 1805–23. http://dx.doi.org/10.1175/jamc-d-17-0195.1.
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AbstractThe properties of clouds derived from measurements collected using a suite of remote sensors on board the Australian R/V Investigator during a 5-week voyage into the Southern Ocean during March and April 2016 are examined. Based on the findings presented in a companion paper (Part I), we focus our attention on a subset of marine boundary layer (MBL) clouds that form a substantial portion of the cloud-coverage fraction. We find that the MBL clouds that dominate the coverage fraction tend to occur in decoupled boundary layers near the base of marine inversions. The thermodynamic conditions under which these clouds are found are reminiscent of marine stratocumulus studied extensively in the subtropical eastern ocean basins except that here they are often supercooled with a rare presence of the ice phase, quite tenuous in terms of their physical properties, rarely drizzling, and tend to occur in migratory high pressure systems in cold-air advection. We develop a simple cloud property retrieval algorithm that uses as input the lidar-attenuated backscatter, the W-band radar reflectivity, and the 31-GHz brightness temperature. We find that the stratocumulus clouds examined have water paths in the 15–25 g m−2 range, effective radii near 8 μm, and number concentrations in the 20 cm−3 range in the Southern Ocean with optical depths in the range of 3–4. We speculate that addressing the high bias in absorbed shortwave radiation in climate models will require understanding the processes that form and maintain these marine stratocumulus clouds in southern mid- and high latitudes.