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Many forest ecosystems are in decline around the world due to increasing biotic and abiotic stresses. Marri (Corymbia calophylla) is an endemic and common eucalypt species of southwestern Australia, which is in decline primarily due to stem canker caused by the pathogenic fungus Quambalaria coyrecup. This study determined to what extent disease susceptibility and plant growth were associated with climate at origin for eight provenances of marri. Plants of all provenances were grown in a common garden with or without pathogen inoculation. Disease development and physiological performance of plants were monitored during an initial irrigated and subsequent terminal drought period. Provenances from drier regions were more susceptible to the fungal pathogen than those from wetter regions, having on average 31% higher incidence rates at 20 days post‐inoculation (dpi) and larger canker lesions at 130 dpi (on average 49% increase) and 230 dpi (on average 42% increase). However, canker development for each provenance was fastest during the initial irrigated wetter growing period. Overall, the average relative canker growth rate was 4‐fold higher during the irrigated period compared to the terminal drought period (p <.001). There were no significant differences between the provenances in leaf water status, photosynthetic rates, or relative growth rates (p >.05). Canker infection reduced both photosynthetic rates and growth rates but only during the later part of the terminal drought period, with significant (p <.05) reductions observed in two out of eight provenances, when plants had relatively large canker sizes. This effect tended to be strongest in the provenances from drier regions as they had relatively larger canker sizes than the provenances from wetter regions. We propose that the increased susceptibility of drier provenances is related to their lower exposure to the pathogen in their drier habitats. Since this is potentially due to suboptimal defence responses, using provenances from drier locations to 'future‐proof' local restoration outcomes in a drying climate may be counterproductive due to plant–pathogen interactions. [ABSTRACT FROM AUTHOR]

Functional traits are proxies for a species' ecology and physiology and are often correlated with plant vital rates. As such they have the potential to guide species selection for restoration projects. However, predictive trait‐based models often only explain a small proportion of plant performance, suggesting that commonly measured traits do not capture all important ecological differences between species. Some residual variation in vital rates may be evolutionarily conserved and captured using taxonomic groupings alongside common functional traits. We tested this hypothesis using growth rate data for 17,299 trees and shrubs from 80 species of Eucalyptus and 43 species of Acacia, two hyper‐diverse and co‐occurring genera, collected from 497 neighborhood plots in 137 Australian mixed‐species revegetation plantings. We modeled relative growth rates of individual plants as a function of environmental conditions, species‐mean functional traits, and neighbor density and diversity, across a moisture availability gradient. We then assessed whether the strength and direction of these relationships differed between the two genera. We found that the inclusion of genus‐specific relationships offered a significant but modest improvement to model fit (1.6%–1.7% greater R2 than simpler models). More importantly, almost all correlates of growth rate differed between Eucalyptus and Acacia in strength, direction, or how they changed along the moisture gradient. These differences mapped onto physiological differences between the genera that were not captured solely by measured functional traits. Our findings suggest taxonomic groupings can capture or mediate variation in plant performance missed by common functional traits. The inclusion of taxonomy can provide a more nuanced understanding of how functional traits interact with abiotic and biotic conditions to drive plant performance, which may be important for constructing trait‐based frameworks to improve restoration outcomes. [ABSTRACT FROM AUTHOR]

Alpine plants in Australia are increasingly exposed to more frequent drought and heatwaves, with significant consequences for physiological stress responses. Acclimation is a critical feature that allows plants to improve tolerance to environmental extremes by directly altering their physiology or morphology. Yet it is unclear how plant performance, tolerance, and recovery are affected when heat and water stress co-occur, and whether prior exposure affects responses to subsequent climate extremes. We grew a common alpine grass species under high or low watering treatments for three weeks before exposure to either none, one, or two heat stress events. We determined photosynthetic heat and freezing tolerance (LT50, mean temperature causing 50% irreversible damage to photosystem II) and growth. Physiological adjustments to low watering, including more negative water potentials and reduced growth, were also characterised by improved tolerance to high and low-temperature extremes. Shifts to higher heat tolerance were also evident with increasing exposure to heat stress events, though freezing tolerance was not affected. Acclimation effects were mostly short-term, however; prior exposure to heat and/or water stress had little to no effect on growth and thermal tolerance following the six-week recovery period. We conclude that rapid acclimation to water and heat stress that co-occur during summer enhances the capacity of alpine plants to tolerate increasingly frequent temperature extremes. [ABSTRACT FROM AUTHOR]

Two saltmarsh locations within Lake Macquarie, NSW, Australia were selected to investigate the uptake and partitioning of metal(loid)s Cu, Zn, As, Se, Cd and Pb in the Australian saltmarsh halophyte, Sarcocornia quinqueflora and the associated sub-lethal effects of metal(loid)s on plant health, including photosynthetic performance, biomass, and productivity. Metal(loid)s primarily accumulated to roots (BCF > 1). Barriers to transport were observed at the root to non-photosynthetic stem transition (TF < 1) for all metal(loid)s, suggesting this species is suitable for phytostabilisation. Sediment and plant tissue metal(loid) concentrations were significantly correlated with photosynthetic performance and plant biomass. As such, the action of sediment and tissue metal(loid)s on photosynthetic performance and the subsequent effect on biomass of S.quinqueflora appear to be suitable targets for molecular analyses to further elucidate mechanisms responsible for the observed adverse effects and the development of adverse outcome pathways. • S. quinqueflora suitable for phytostabilisation of metal(loid)s • Essential metals regulated whilst non-essential metals accumulated in S.quinqueflora • Roots suitable bioindicator of Cd and Pb contamination • Metal(loid)s in sediment or tissues correlated with Chl fluorescence and biomass • Chl fluorescence parameters correlated with S.quinqueflora biomass [ABSTRACT FROM AUTHOR]

Summary: Understanding the current and future distributions of plant pathogens is critical to predict the plant performance and related economic benefits in the changing environment. Yet, little is known about the roles of environmental drivers in shaping the profiles of fungal plant pathogens in phyllosphere, an important habitat of microbiomes on Earth. Here, using a large‐scale investigation of Eucalyptus phyllospheric microbiomes in Australia and the multiple linear regression model, we show that precipitation is the most important predictor of fungal taxonomic diversity and abundance. The abundance of fungal plant pathogens in phyllosphere exhibited a positive linear relationship with precipitation. With this empirical dataset, we constructed current and future atlases of phyllosphere plant pathogens to estimate their spatial distributions under different climate change scenarios. Our atlases indicate that the abundance of fungal plant pathogens would increase especially in the coastal regions with up to 100‐fold increase compared with the current abundance. These findings advance our understanding of the distributions of fungal plant pathogens in phyllospheric microbiomes under the climate change, which can improve our ability to predict and mitigate their impacts on plant productivity and economic losses. [ABSTRACT FROM AUTHOR]

We tested the 'enemy release hypothesis' in relation to Lonicera japonica to determine the effects of soil microbes on plant growth. It was hypothesized that plant performance in the introduced range in Australia would be increased by escaping natural enemies in soils in its native range of Japan, and thus there was increased likelihood of invasion success. Greenhouse experiments were carried out where plants (stem cuttings) of L. japonica were inoculated with soil microbiota (conspecifics vs. heterospecifics) from either the native range in Japan or the introduced range in Australia. Survival rates and plant growth characteristics were documented, and overall plant performance as feedbacks were calculated. The results showed that the growth of L. japonica was influenced by soil microbial communities. Plant growth performance indicated strong negative feedback when grown in its native-range soil and positive feedback when grown in its introduced range soil. Difference between ranges was noticed that includes more positive feedback when L. japonica was grown in conspecific soil compared to when it was grown in the conditioned by heterospecifics from the introduced range and more negative feedback in conspecific soils compared to heterospecific soil in the native range. The findings are consistent with the 'enemy release hypothesis' and clearly indicate that plant–soil microbes' interactions of L. japonica can play an important role in facilitating the survival and growth of L. japonica in its introduced range. [ABSTRACT FROM AUTHOR]

Perennial ryegrass (Lolium perenne L.) is the predominant perennial forage species used in temperate irrigated dairy-production systems in Australia. However, when temperatures are high, even with optimal irrigation strategies and nutrient inputs, dry matter (DM) production can be compromised. This research investigated the effects of perennial ryegrass and tall fescue genotypes and summer irrigation on (DM) production and survival. Ten perennial ryegrass cultivars, three hybrid ryegrasses and two cultivars of tall fescue (Festuca arundinacea (Schreb) Darbysh.) were sown in northern Victoria, Australia, in May 2014, and were managed under full irrigation or restricted irrigation (no irrigation between late December and mid-March) over a 3-year period. Measurements included net pasture accumulation (DM production), sward density (plant frequency) and water-soluble carbohydrate concentration. Apart from the expected differences in DM yield over the summer period between full irrigation and restricted irrigation, there were few differences in DM production among perennial ryegrass or tall fescue cultivars. Plant frequency declined significantly under restricted irrigation in Years 2 and 3 compared with full irrigation but there were no differences among perennial ryegrass cultivars. In Year 2, plant frequency was higher in the tall fescue cultivars than the ryegrass cultivars. The recovery pattern in DM production following recommencement of irrigation in mid-March (autumn) varied across years. In Year 1, plants recovered rapidly once irrigation recommenced in autumn. However, in Years 2 and 3, autumn and winter pasture accumulation under restricted irrigation was 30–35% less than under full irrigation. These differences were possibly related to decreases in plant frequency, as well as to differences in the amounts of residual pasture mass (or carbohydrate reserves) present when growth ceased. Analyses of the water-soluble carbohydrate concentrations in the pseudostem during summer and autumn in Year 3 showed differences in total water-soluble carbohydrate and in fructan and sucrose concentrations between irrigation treatments but no consistent differences among genotypes. Perennial ryegrass is the predominant perennial forage species in temperate irrigated dairy systems in Australia; however, its summer production can be poor. This research investigated the effects of genotype and summer irrigation on growth and survival of 15 perennial ryegrass and tall fescue genotypes. Dry matter production and plant frequency were reduced under restricted irrigation and there were few differences among cultivars, suggesting that plant performance over summer may be more influenced by irrigation management than by cultivar selection. [ABSTRACT FROM AUTHOR]

Modeling of geometallurgical variables is becoming increasingly important for improved management of mineral resources. Mineral processing circuits are complex and depend on the interaction of a large number of properties of the ore feed. At the Olympic Dam mine in South Australia, plant performance variables of interest include the recovery of Cu and U 3O 8, acid consumption, net recovery, drop weight index, and bond mill work index. There are an insufficient number of pilot plant trials (841) to consider direct three-dimensional spatial modeling for the entire deposit. The more extensively sampled head grades, mineral associations, grain sizes, and mineralogy variables are modeled and used to predict plant performance. A two-stage linear regression model of the available data is developed and provides a predictive model with correlations to the plant performance variables ranging from 0.65–0.90. There are a total of 204 variables that have sufficient sampling to be considered in this regression model. After developing the relationships between the 204 input variables and the six performance variables, the input variables are simulated with sequential Gaussian simulation and used to generate models of recovery of Cu and U 3O 8, acid consumption, net recovery, drop weight index, and bond mill work index. These final models are suitable for mine and plant optimization. [ABSTRACT FROM AUTHOR]

Abstract: Substantial structural reform has occurred in the water and wastewater sectors of Australia’s major urban centers over the past two decades. This reform has involved the corporatization of government assets and some vertical and horizontal separation. This paper analyses the performance of these sectors since the mid 1990s. In particular, it uses Malmquist Data Envelopment Analysis (DEA) to determine the different levels of productivity and efficiency improvement over this period. The results point to modest, but positive productivity gains in the larger urban centers, independent of industry structure. Further, it highlights the need to consider exogenous factors that can influence productivity outcomes in an industry generally associated with monopoly characteristics and dependent on water sources that are, to varying extents, unpredictable and uncontrollable. [Copyright &y& Elsevier]

• Impact of dry cooling tower design on supercritical CO 2 power cycle performance. • Seasonal and annual variation of plant net power generation and tower performance. • Daily power fluctuations of the supercritical CO 2 power plant are studied. • Fluctuation of heat input, heat rejection, and air mass flow are examined. • Various plant performance indicators are evaluated. The dry cooling unit is integrated with a 25 MW recompression super-critical CO 2 (sCO 2) cycle for solar energy application. Based on the optimal operating condition, a natural draft dry cooling tower (NDDCT) is modelled for an ambient temperature of 20 °C and sCO 2 inlet condition of 67 °C and 7.96 MPa. The Kroger's detailed working principle of NDDCT is adapted in the simulation processes. The sCO 2 property variation with the change of bulk temperature is considered while modelling the heat exchanger unit inside the tower. The draft equation of the tower is solved by including various air-flow resistances at different parts of the tower. The heat input to the cycle is assumed to be supplied by the solar field with sufficient capacity of thermal storage. The seasonal effect on the performance of a dry-cooled sCO 2 recompression cycle is performed in Alice Spring, NT, Australia by using the daily meteorological data. The daily net power generation fluctuates in the range of 2.4% to 22.4% of the design value for the consecutive days. The year-round mean net power generation is 24.66 MW which corresponds to 50.9% cycle efficiency. The weekly and monthly seasonal variation of the plant performance in summer, autumn, winter, and spring is performed based on the mean maximum and minimum temperature data. The mean net power produced in summer and winter is 22.9 MW and 26.4 MW respectively. The fluctuation of heat input to the cycle, heat rejected by the cycle and air mass flow rate in NDDCT are demonstrated. Seven performance indicators (Thermal efficiency, exergetic performance criteria, exergy efficiency, maximum available work, ecological coefficient of performance, cooling efficiency, and ecological function criteria) are determined to evaluate the plant performance for the period of 1941 to 2018 using the mean temperature data. [ABSTRACT FROM AUTHOR]