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1. Changes in vegetation community composition, such as a transition from grassland to shrubland (woody encroachment), are associated with reductions in plant cover and increases in bare ground. Encroachment‐driven changes in surface cover at small spatial scales can alter ant community assemblages by changing their foraging behaviour and their ability to locate and monopolise resources. 2. Artificial arenas with three levels of complexity were used to examine changes in ant foraging efficiency, body size and ability to monopolise food. The three levels of complexity included a control (no substrate), low‐complexity treatment (woody debris) and high‐complexity treatment (leaf litter). 3. No difference was found in ant species composition within the complexity arenas between grassland and shrubland, but ant functional groups ‘generalised Myrmicinae’ and ‘subordinate Camponotini’ were more abundant in grassland arenas, whereas ‘opportunists’ were more abundant in shrubland arenas. Ants took twice as long to find baits in high‐complexity treatments, and 1.5 times as long in low‐complexity treatments, than in control treatments, which were bare arenas with no substrate. Ant body size declined with increasing surface complexity, suggesting that larger ants are discouraged from foraging in complex habitats. 4. There was also significantly greater monopolisation of the protein bait (tuna) in low‐ and high‐complexity treatments, but there were no differences between tuna and carbohydrate (honey) in the control treatment. Consistently, no differences were found in ant behaviour between grasslands and shrublands. 5. The present study shows that ants are more responsive to small‐scale alterations in soil surface complexity than to changes in vegetation community composition. Changes in soil surface complexity select for ants based on body size, which in turn influences their foraging success. Changes in vegetation complexity at small spatial scales are therefore likely to influence ant behaviour and abundance of some functional groups, potentially having an effect on the many ecosystem functions carried out by ants. [ABSTRACT FROM AUTHOR]

Background Obtaining informed consent from patients considering bunion surgery can be challenging. This study assessed the efficacy of a multimedia technology as an adjunct to the informed consent process. Methods A prospective, cohort study was conducted involving 55 patients (7 males, 48 females) who underwent a standardized verbal discussion regarding bunion correction surgery followed by completion of a knowledge questionnaire. A multimedia educational program was then administered and the knowledge questionnaire repeated. Additional supplementary questions were then given regarding satisfaction with the multimedia program. Results Patients answered 74% questions correctly before the multimedia module compared with 94% after it ( P < 0.0001). Patients rated the ease of understanding and the amount of information provided by the module highly. Eighty-four percent of patients considered that the multimedia tool performed as well as the treating surgeon. Conclusion Multimedia technology is useful in enhancing patient knowledge regarding bunion surgery for the purposes of obtaining informed consent. [ABSTRACT FROM AUTHOR]

Abstract We examined the dynamics of cryptogamic soil crusts in a derived (disclimax) grassland near Orange in south-eastern Australia. Changes in the cover of cryptogamic crusts and floristics and abundance of the constituent species were measured on four treatments with two levels each of grazing and cultivation. Twenty-two lichens, mosses and liverworts were found at the study site and, of these, 13 were collected in the quadrats. Three moss species (Barbula calycina, Eccremidium arcuatum and Bryum pachytheca) and one lichen species (Cladonia tessalata) accounted for 67% of total cover-abundance scores. Generally, cover-abundance was significantly higher in the unvegetated microsites than in the vegetated microsites. Species richness was not significantly different between the four grazing-cultivation treatments but, on average, there were significantly more species in the unvegetated microsites (mean = 3.2 species) than in the vegetated microsites (0.54 species). Grazing and cultivation resulted in significantly greater cover of bare ground and consequently significantly greater crust cover. Averaged across all treatments, approximately half of the area of unvegetated soil was occupied by cryptogams. Overall, the results indicate that lichens and bryophytes are important components of derived temperate grasslands, surviving in even densely vegetated swards. This study suggests that strategies which disturb the soil surface (e.g. grazing and cultivation) will stimulate the abundance and cover of soil crust organisms by increasing the availability of unvegetated microsites. [ABSTRACT FROM AUTHOR]

Abstract Hip holes are shallow, reniform-shaped depressions found next to the trunks of many trees and shrubs in arid and semi-arid Australia. They are constructed by kangaroos (Macropus spp.), who use them as diurnal resting sites, particularly during hot weather. Physical and chemical properties of soils in hip holes were compared with non-hole microsites adjacent to the trunk (‘trunk’), microsites below the canopy (‘canopy’) and microsites out in the open (‘open’) under two trees (Eucalyptus intertexta , Alectryon oleifolius ) and one shrub (Dodonaea viscosa ) in a semi-arid woodland in eastern Australia. Overall, there were few effects under D. viscosa apart from a greater (10-fold) mass of litter in the hip holes compared with the trunk microsite. Hip holes under E. intertexta and A. oleifolius , however, contained six times more dung compared with the trunk microsite. For the two tree species, soils in the hip holes were significantly more erodible, as measured by aggregation levels, compared with the other microsites, but there were no significant differences in bulk density nor pH. Steady-state infiltration rates at the hip hole and trunk microsites were significantly greater than those in the open, but there was no significant hip hole effect. Soils in the hip holes contained greater levels of exchangeable calcium and magnesium (E. intertexta ) and greater exchangeable sodium (A. oleifolius ) compared with trunk microsites. Hip holes under E. intertexta contained approximately 68% more organic carbon, total carbon and nitrogen, and 86% more sulfur compared with trunk microsites. Similarly, hip holes under A. oleifolius contained on average 38% more organic and total carbon, and 47% more nitrogen than trunk microsites. Given the density of hip holes and their impact on soil chemistry, kangaroos are considered to be important elements in the maintenance of heterogeneity in these woodlands. [ABSTRACT FROM AUTHOR]