Paull, NJ, Krix, D, Irga, PJ & Torpy, FR 2020, 'Airborne particulate matter accumulation on common green wall plants.', International journal of phytoremediation, pp. 1-13.View/Download from: Publisher's site
In order to better design greening systems for effective particulate matter (PM) removal, it is important to understand the impact leaf traits have on PM deposition. There are however, inconsistences amongst the leaf traits that have previously been correlated with PM accumulation. The aim of this paper was to identify vegetation characteristics of green wall plants that were associated with the accumulation of particulate matter. To determine patterns associated with different leaf morphologies, eleven common ornamental plant species were sampled across 15 sites, over a 6 month duration. PM deposition was determined gravimetrically and its associated size fractions determined microscopically. Linear mixed models were used to identify statistical patterns relating to differences in PM deposition across plant species. PM deposition and the relative frequencies of particle size fractions were found to be statistically different among species, sites and months. Green wall plants were shown to be effective at PM accumulation as all of the assessed plant species had equivalent PM removal efficiency, with minimal evidence of influential leaf characteristics that could enhance PM removal.
Paull, NJ, Krix, D, Torpy, FR & Irga, PJ 2020, 'Can green walls reduce outdoor ambient particulate matter, noise pollution and temperature?', International Journal of Environmental Research and Public Health, vol. 17, no. 14, pp. 1-19.View/Download from: Publisher's site
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Green walls have previously demonstrated the capacity to reduce particulate matter (PM), noise pollution, and temperature conditions in manipulative experiments and computational models. There is, however, minimal evidence that green walls can influence ambient environmental conditions, especially taking into account the variable environmental conditions encountered in situ. The aim of this paper was to determine if green walls have a quantitative effect on ambient air quality in an urban environment. Ambient PM, noise, and temperature were recorded at 12 green wall and adjacent reference wall locations across a dense urban centre, over a 6-month period. The results indicated that PM levels and temperature did not significantly differ between the green wall and reference wall sites. Ambient noise at the green wall sites, however, was significantly lower than at the reference wall locations. It is suggested that mechanically assisted, or 'active' green wall systems may have a higher PM and temperature reduction capacity, and if so, they will be more valuable for installation in situ compared to standard passive systems, although this will require further research.
Murray, BR, Brown, C, Murray, ML, Krix, DW, Martin, LJ, Hawthorne, T, Wallace, MI, Potvin, SA & Webb, JK 2020, 'An Integrated Approach to Identify Low-Flammability Plant Species for Green Firebreaks', Fire, vol. 3, pp. 1-5.View/Download from: Publisher's site
Knight, S, Leigh, A, Davila, Y, Martin, L & Krix, D 2019, 'Calibrating Assessment Literacy Through Benchmarking Tasks', Assessment and Evaluation in Higher Education, vol. 44, no. 8, pp. 1121-1132.View/Download from: Publisher's site
In calibration tasks students assess exemplar texts using criteria against which their own work will be assessed. Typically these tasks are used in the context of training for peer assessment. Little research has been conducted on the benefits of calibration tasks, such as benchmarking, as learning opportunities in their own right. This paper examines a dataset from a long-running benchmarking task ( 500 students per semester, for four semesters). We investigate the relationship of benchmarking performance to other student outcomes, including ability to self-assess accurately. We show that students who complete the benchmarking perform better, that there is a relationship between benchmarking performance and self-assessment performance, and that students appreciate the support for learning that benchmarking tasks provide. We discuss implications for teaching and learning flagging the potential of calibration tasks as an under-explored tool.
Krix, DW, Phillips, ML & Murray, BR 2019, 'Relationships among leaf flammability attributes and identifying low-leaf-flammability species at the wildland-urban interface', International Journal of Wildland Fire, vol. 28, no. 4, pp. 295-297.View/Download from: Publisher's site
© 2019 IAWF. Leaf flammability is a multidimensional plant functional trait with emerging importance for wildfire risk management. Understanding relationships among leaf flammability attributes not only provides information about the properties of leaves as fuels in the wildland-urban interface (WUI), it can also offer an effective way to identify low-leaf-flammability species. We examined relationships between leaf ignitibility, sustainability and combustibility among 60 plant species of the WUI of eastern Australia. We found that leaf ignitibility and sustainability worked in opposition to each other as dimensions of flammability. Species with leaves that were slow to ignite were those with leaves that sustained burning for the longest, whereas species with leaves that were fast to ignite had leaves that burned for the shortest periods of time. Low leaf combustibility was related to short leaf burning sustainability but not to ignitibility. We created an overall leaf flammability index (OLFI) to rank species on emergent properties of ignitibility, sustainability and combustibility attributes in combination. We found that low-leaf-flammability species with low OLFI values had small leaf area, high leaf mass per area and high leaf water content. Our findings have implications for species selection for green firebreaks in the WUI.
Murray, BR, Martin, LJ, Brown, C, Krix, DW & Phillips, ML 2018, 'Selecting low-flammability plants as green firebreaks within sustainable urban garden design', Fire, vol. 1, no. 1, pp. 1-4.View/Download from: Publisher's site
In response to an increasing risk of property loss from wildfires at the urban–wildland interface, there has been growing interest around the world in the plant characteristics of urban gardens that can be manipulated to minimize the chances of property damage or destruction. To date, considerable discussion of this issue can be found in the 'grey' literature, covering garden characteristics such as the spatial arrangement of plants in relation to each other, proximity of plants to houses, plant litter and fuel reduction, and the use of low-flammability plants as green firebreaks [1,2,3,4]. Recently, scientific studies from a geographically wide range of fire-prone regions including Europe , the USA , Australia , South Africa , and New Zealand  have been explicitly seeking to quantify variation among plant species with respect to different aspects of their flammability and to identify low-flammability horticultural species appropriate for implementation as green firebreaks in urban landscapes. The future prospects of this scientific work will ultimately depend on how successfully the results are integrated into the broader context of garden design in fire-prone regions at the urban–wildland interface. Although modern design of urban gardens must consider more than just the issue of green firebreaks, we and others [10,11] believe that selection of low-flammability plants should be high on the priority list of plant selection criteria in fire-prone regions.
Hingee, MC, Eamus, D, Krix, DW, Zolfagher, S & Murray, BR 2017, 'Patterns of plant species composition in mesic woodlands are related to a naturally occurring depth-to-groundwater gradient', Community Ecology, vol. 18, pp. 21-30.
Nguyen, KQ, Cuneo, P, Cunningham, SA, Krix, DW, Leigh, A & Murray, BR 2016, 'Ecological effects of increasing time since invasion by the exotic African olive (Olea europaea ssp. cuspidata) on leaf-litter invertebrate assemblages', Biological Invasions, vol. 18, no. 6, pp. 1689-1699.View/Download from: Publisher's site
© 2016 Springer International Publishing Switzerland Invasive African olive, Olea europaea ssp. cuspidata (Wall. ex G.Don) Cif., forms increasingly dense stands between initial and mature stages of invasion, leading to a progressive decline in native plant diversity. Here, we examined the response of leaf-litter invertebrates to increasing time since olive invasion. We compared invertebrate assemblages among early-stage olive (0–7 years since invasion, scattered olive shrubs and seedlings in native woodland), mature olive (>15 years, uniform olive stands dominated by multi-trunked trees) and uninvaded native grassy woodland habitats (both mature stands and edges) in a critically endangered ecological community of south-eastern Australia. Invertebrate species richness was significantly reduced in mature olive compared with early-stage olive and mature native woodland habitats. Species richness did not differ significantly between early-stage olive habitat and mature native woodland, demonstrating resistance in species richness to initial invasion. Invertebrate species composition of native woodlands differed significantly from both mature olive and early-stage olive habitats, demonstrating a lack of resistance in species composition to initial olive invasion. Compositional differences were principally driven by reduced abundances within Coleoptera, Hymenoptera and Polyxenida in mature olive habitat compared with mature native woodland. These changes were significantly correlated with an increase in bare ground, plant canopy cover and litter depth, and higher moisture and lower temperature within leaf litter, in mature olive habitat. Our findings show that negative ecological impacts of invasive African olive extend beyond plants to leaf-litter invertebrate assemblages and that significant impacts on invertebrate species assemblage composition occur early in the invasion process.