Gap-crossing decisions of forest birds in a fragmented landscape

Habitat loss and fragmentation are recognized as primary drivers of biodiversity loss worldwide. To understand the functional effects of habitat fragmentation on bird populations, data on movement across gaps in habitat cover are necessary, although rarely available. In this study, we used call playback to simulate a conspecific territorial intruder to entice birds to move through the landscape in a predictable and directional manner. We then quantified the probability of movement in continuous forest and across cleared gaps for two forest-dependent species, the grey shrike-thrush (Colluricincla harmonica) and the white-throated treecreeper (Cormobates leucophaeus). Fifty-four playback trials were conducted for each species across distances ranging from 25 to 480 m in continuous forest and 15-260 m across gaps in a forest-agricultural landscape in southern Victoria, Australia. The probability of movement was significantly reduced by gaps in forest cover for both species. Shrike-thrushes were six times more likely to move 170 m in continuous forest than to cross 170-m gaps. The mean probability that treecreepers would cross any gap at all was less than 0.5, and they were three times less likely to move 50 m across a gap than through continuous forest. Both species displayed non-linear responses to increasing gap distance: we identified a gap-tolerance threshold of 85 m for the shrike-thrush and 65 m for the treecreeper beyond which individuals were most unlikely to cross. The presence of scattered paddock trees increased functional connectivity for the shrike-thrush, with individuals crossing up to 260 m when scattered trees were present. We conclude that gaps in habitat cover are barriers to movement, and that characteristics of the intervening matrix influence landscape permeability.

Are adolescents from a forest community well-informed about forest management?

The indigenous community of San Juan Nuevo Parangaricutiro in Mexico has been engaged in a successful Community Forest Enterprise employing sustainable management practices since 1981. These environmental practices do not seem to be reflected in the educational programmes developed at school. In this study, the environmental knowledge and interest of 102 students at high-school (15 to 18 years old) towards forestry management were analysed. The association between their knowledge and interests in environmental issues was also estimated. These analyses examine their interest in forest management as potential employment and the effect of the educational system on environmental learning. A combination of quantitative and qualitative methods was used. Results showed that environmental concepts were poorly understood despite their inclusion in the curriculum. Adolescents did not envisage working in the forest in the future because they showed no interest in forest activities. Educational implications and strategies to encourage adolescents to become involved in community forest management are crucial for conservation.

Toward sustainable forest management : the potential contribution of timber certification and product labelling in Victoria

Sustainable forest management has emerged as a major international forestry issue. This research assessed the potential contribution of certification and labelling to sustainable forest management in Victoria. The results indicate a potential demand for certified forest products and a consumer willingness to pay to ensure forests are managed sustainably.

A critical review of multi-criteria decision making methods with special reference to forest management and planning

This paper provides a review of research contributions on forest management and planning using multi-criteria decision making (MCDM) based on an exhaustive literature survey. The review primarily focuses on the application aspects  highlighting theoretical underpinnings and controversies. It also examines the nature of the problems addressed and incorporation of risk into forest  management and planning decision making. The MCDM techniques covered in this review belong to several schools of thought. For each technique, a variety of empirical applications including recent studies has been reviewed. More than 60 individual studies were reviewed and classified by the method used, country of origin, number and type of criteria and options evaluated. The review serves as a guide to those interested in how to use a particular MCDM approach. Based on the review, some recent trends and future research directions are also highlighted.

Non-linear effects of landscape properties on mistletoe parasitism in fragmented agricultural landscapes

Ecological processes such as plant–animal interactions have a critical role in shaping the structure and function of ecosystems, but little is known of how such processes are modified by changes in landscape structure. We investigated the effect of landscape change on mistletoe parasitism in fragmented agricultural environments by surveying mistletoes on eucalypt host trees in 24 landscapes, each 100 km² in size, in south-eastern Australia. Landscapes were selected to represent a gradient in extent (from 60% to 2% cover) and spatial pattern of remnant wooded vegetation. Mistletoes were surveyed at 15 sites in each landscape, stratified to sample five types of wooded elements in proportion to their relative cover. The incidence per landscape of box mistletoe (Amyema miquelii), the most common species, was best explained by the extent of wooded cover (non-linear relationship) and mean annual rainfall. Higher incidence occurred in landscapes with intermediate levels of cover (15–30%) and higher rainfall (>500 mm). Importantly, a marked non-linear decline in the incidence of A. miquelii in low-cover landscapes implies a disproportionate loss of this species in remaining wooded vegetation, greater than that attributable to decreasing forest cover. The most likely mechanism is the effect of landscape change on the mistletoebird (Dicaeum hirundinaceum), the primary seed-dispersal vector for A. miquelii. Our results are consistent with observations that habitat fragmentation initially enhances mistletoe occurrence in agricultural environments; but in this region, when wooded vegetation fell below a threshold of ~15% landscape cover, the incidence of A. miquelii declined precipitously. Conservation management will benefit from greater understanding of the components of landscape structure that most influence ecological processes, such as mistletoe parasitism and other plant–animal mutualisms, and the critical stages in such relationships. This will facilitate action before critical thresholds are crossed and cascading effects extend to other aspects of ecosystem function.

Random forest based lung nodule classification aided by clustering

An automated lung nodule detection system can help spot lung abnormalities in CT lung images. Lung nodule detection can be achieved using template-based, segmentation-based, and classification-based methods. The existing systems that include a classification component in their structures have demonstrated better performances than their counterparts. Ensemble learners combine decisions of multiple classifiers to form an integrated output. To improve the performance of automated lung nodule detection, an ensemble classification aided by clustering (CAC) method is proposed. The method takes advantage of the random forest algorithm and offers a structure for a hybrid random forest based lung nodule classification aided by clustering. Several experiments are carried out involving the proposed method as well as two other existing methods. The parameters of the classifiers are varied to identify the best performing classifiers. The experiments are conducted using lung scans of 32 patients including 5721 images within which nodule locations are marked by expert radiologists. Overall, the best sensitivity of 98.33% and specificity of 97.11% have been recorded for proposed system. Also, a high receiver operating characteristic (ROC) A_z of 0.9786 has been achieved.

Post-prandial remnant lipids impair arterial compliance

OBJECTIVES
We sought to examine the effects of plasma lipids, especially in remnants after a fat meal, on systemic arterial compliance (SAC), a newly recognized cardiovascular risk factor.
BACKGROUND
Post-prandial remnants correlate with coronary heart disease events through mechanisms that may include vascular dysfunction, although the effect on SAC has not been studied.
METHODS
Systemic arterial compliance was measured non-invasively over 6 h after a fat meal in 16 subjects with varying plasma triglyceride levels. Changes were related to rises in plasma lipids and remnant lipids. Systemic arterial compliance was measured in 20 subjects after a control low-fat meal.
RESULTS
The fat meal induced increments in plasma triglyceride and remnant cholesterol and triglyceride (respectively +54%, 50% and 290% at 3 h, analysis of variance <0.001). Systemic arterial compliance fell at 3 h and 6 h by 25% and 27% (analysis of variance <0.001). Baseline SAC correlated significantly with all lipid concentrations at 0, 3 h and 6 h, but only with triglyceride on stepwise regression analysis. The SAC response to the low-fat meal was very small and not significant.
CONCLUSIONS
This is the first demonstration of SAC becoming impaired after a fat meal. Remnant lipids and plasma total triglyceride appeared to contribute to the fall in SAC.

Spatial ecology of sooty owls in south-eastern Australian coastal forests : implications for forest management and reserve design

We investigated the home-range size and habitat use of eight Sooty Owls (Tyto tenebricosa tenebricosa) in coastal forests in East Gippsland, Victoria, Australia, between November 2006 and January 2008. The size of home-ranges varied widely; based on 95% adaptive kernel estimates, the average size of home-ranges of males was 3025ha (±1194s.d., n=3), whereas that of females was 994ha (±654s.d., n=5). Sooty Owls utilised a broad range of ecological vegetation classes and topographical features for roosting and foraging at a greater scale than previously assumed. There was minimal selection for habitat types based on floristic composition, primarily only avoiding heathlands (for foraging and roosting) and selecting particular dense foliage (rainforest and riparian scrub) for foliage roosting. Two Owls maintained home-ranges close to logged areas, with logging regrowth (<45 years old) being strongly avoided by both individuals. We recommend that the size of individual reserves for Sooty Owls in commercial forests should be increased to more closely resemble the core spatial resource requirements needed by a pair. Reserves should be largest where they feed predominantly on hollow-dependent prey. Most importantly, rather than conservation measures just focussing on the spatial requirements of Sooty Owls, efforts should be directed towards retaining high densities of crucial resources, such as hollow-bearing trees and mammalian prey species throughout the landscape.