A hairy situation: Plant species in warm, sunny places are more likely to have pubescent leaves

Aim: Leaf pubescence has several important roles, including regulating heat balance, reducing damage from UV radiation, minimizing water loss and reducing herbivory. Each of these functions could affect a plant's ability to tolerate the biotic and abiotic stresses encountered in different parts of the world. However, we know remarkably little about large scale biogeographic patterns in leaf pubescence. Our aims were: (a) to determine whether a higher proportion of species have pubescence at sites where it is hot, dry and solar radiation is high, and (b) to quantify the latitudinal gradient in pubescence. Location: Australia. Taxon: Vascular land plants. Methods: We compiled data on the presence/absence of pubescence on mature photosynthetic organs for 4,183 species, spanning 107 families. We combined these data with over 1.9 million species occurrence records from the Atlas of Living Australia to calculate the proportion of species with pubescence in 3,261 grid cells spanning the Australian continent. Results: The proportion of pubescent species was most closely related to solar radiation (R2 = 0.33), followed by maximum temperature in the warmest month (R2 = 0.30). Mean annual precipitation was very weakly related to pubescence (R2 = 0.01). We found a significant negative relationship between latitude and pubescence (R2 = 0.19), with the average percentage of species with pubescence dropping from 46% at 10° S to 35% at 44° S. This cross-species relationship remained significant after accounting for phylogenetic relationships between species. We found that a quadratic model explained more variation in pubescence across latitudes than did a linear model. The quadratic model shows a peak in the proportion of pubescent species at 19° S (within the tropics). Main conclusions: Our findings are consistent with the idea that leaf pubescence may have a protective function in areas with high solar radiation and high temperatures. Our data are also consistent with the idea that species towards the tropics should be better defended than are species at higher latitudes

Macroecological patterns in flower colour are shaped by both biotic and abiotic factors

There is a wealth of research on the way interactions with pollinators shape flower traits. However, we have much more to learn about influences of the abiotic environment on flower colour. We combine quantitative flower colour data for 339 species from a broad spatial range covering tropical, temperate, arid, montane and coastal environments from 9.25ºS to 43.75ºS with 11 environmental variables to test hypotheses about how macroecological patterns in flower colouration relate to biotic and abiotic conditions. Both biotic community and abiotic conditions are important in explaining variation of flower colour traits on a broad scale. The diversity of pollinating insects and the plant community have the highest predictive power for flower colouration, followed by mean annual precipitation and solar radiation. On average, flower colours are more chromatic where there are fewer pollinators, solar radiation is high, precipitation and net primary production are low, and growing seasons are short, providing support for the hypothesis that higher chromatic contrast of flower colours may be related to stressful conditions. To fully understand the ecology and evolution of flower colour, we should incorporate the broad selective context that plants experience into research, rather than focusing primarily on effects of plant–pollinator interactions

The potential interaction between time perception and gaming: a narrative review

Compromised time control is a variable of interest among disordered gamers because time spent on videogames can directly affect individuals’ lives. Although time perception appears to be closely associated with this phenomenon, previous studies have not systematically found a relationship between time perception and gaming. Therefore, the purpose of this narrative review is to explore how gaming disorder may be associated with time perception. It has been found that gamers exhibit a stronger attentional focus as well as an improved working memory compared with non-gamers. However, gamers (and especially disordered gamers) exhibit a stronger reaction to gaming cues which—coupled with an altered emotion regulation observed among disordered gamers—could directly affect their time perception. Finally, “'flow states”' direct most of the attentional resources to the ongoing activity, leading to a lack of resources allocated to the time perception. Therefore, entering a flow state will result in an altered time perception, most likely an underestimation of duration. The paper concludes that the time loss effect observed among disordered gamers can be explained via enhanced emotional reactivity (facilitated by impaired emotion regulation)

Potential lantana invasion of the Greater Blue Mountains World Heritage Area under climate change

Invasive weeds represent one of the greatest threats to ecosystem integrity worldwide, with climate change predicted to allow expansion of weed ranges in coming decades. One of Australia's worst weeds is lantana (Lantana camara) which, given the potential for climatic change, is of increasing concern to those managing the mountainous regions in the country's southeast. In order to identify potential additional threats lantana may pose for Australia's valued biodiversity, this research develops a habitat suitability model for lantana in a portion of the Greater Blue Mountains World Heritage Area under current and simulated warmer conditions. Minimum temperature was found to be the most important predictor correlated with potential lantana establishment, explaining over 88% of the variation in lantana presence predicted by the model. Currently, 8% of the study area was found to be suitable for lantana, with this figure reaching 94% after a simulated 2°C rise in temperature anticipated by 2050. The sharp increase in suitable habitat highlights the importance of keeping the weed's range restricted in the study area. The strong link between temperature and predicted lantana establishment confirms prior research and further stresses the threat this weed poses to the area's biodiversity values as the climate warms. In addition, the model identified low-lying riparian areas as potential incursion pathways for the weed to travel further inland. Given the weed's invasiveness, potential for adverse impacts, and high capacity for dispersal, these pathways should not be overlooked when monitoring potential invasion of mountainous regions by lantana and other tropical weeds

Using sediment budgets to investigate the pathogen flux through catchments

We demonstrate a materials budget approach to identify the main source areas and fluxes of pathogens through a landscape by using the flux of fine sediments as a proxy for pathogens. Sediment budgets were created for three subcatchment tributaries of the Googong Reservoir in southeastern New South Wales, Australia. Major inputs, sources, stores, and transport zones were estimated using sediment sampling, dam trap efficiency measures, and radionuclide tracing. Particle size analyses were used to quantify the fine-sediment component of the total sediment flux, from which the pathogen flux was inferred by considering the differences between the mobility and transportation of fine sediments and pathogens. Gullies were identified as important sources of fine sediment, and therefore of pathogens, with the pathogen risk compounded when cattle shelter in them during wet periods. The results also indicate that the degree of landscape modification influences both sediment and pathogen mobilization. Farm dams, swampy meadows and glades along drainage paths lower the flux of fine sediment, and therefore pathogens, in this landscape during low-flow periods. However, high-rainfall and high-flow events are likely to transport most of the fine sediment, and therefore pathogen, flux from the Googong landscape to the reservoir. Materials budgets are a repeatable and comparatively low-cost method for investigating the pathogen flux through a landscape

Road impacts a tipping point for wildlife populations in threatened landscapes

The conservation of wildlife populations living adjacent to roads is gaining international recognition as a worldwide concern. Populations living in road-impacted environments are influenced by spatial parameters including the amount and arrangement of suitable habitat. Similarly, heterogeneity in threatening processes can act at a variety of spatial scales and be crucial in affecting population persistence. Common wombats (Vombatus ursinus) are considered both widespread and abundant throughout their eastern Australian continental distribution. They nevertheless face many threats, primarily human induced. As well as impacts from disease and predation by introduced species, high roadside fatality rates on many rural roads are frequently reported. We parameterized a model for common wombat population viability analysis within a 750-km2 area of the northwestern corner of Kosciuszko National Park in New South Wales, Australia, and tested its sensitivity to changes in the values of basic parameters. We then assessed the relative efficiency of various mitigation measures by examining the combined impact from roads, disease and predation on wombat subpopulation persistence in the area. We constructed a stage-structured and spatially explicit model incorporating estimates of survival and fecundity parameters for each of the identified subpopulations using RAMAS GIS. Estimates of current threatening processes suggest mitigating road-kill is the most effective management solution. Results highlight the importance of recognizing the interplay between various threats and how their combination has the capacity to drive local depletion events. © 2010 The Society of Population Ecology and Springer

Habitat selection by the common wombat (Vombatus ursinus) in disturbed environments: Implications for the conservation of a 'common' species

The construction of habitat models is a repeatable technique for describing and mapping species distributions, the utility of which lies in enabling management to predict where a species is likely to occur within a landscape. Typically, habitat models have been used to establish habitat requirements for threatened species; however they have equal applicability for modelling local populations of common species. Often, few data exist on local populations of common species, and issues of abundance and habitat selection at varying scales are rarely addressed. We provide a habitat suitability model for the common wombat (Vombatus ursinus) in southern New South Wales. This species is currently perceived as abundant throughout its extensive range across temperate regions of eastern Australia, yet little factual survey data exist and populations appear under threat. We use wombat burrows to reflect habitat selection and as our basis for ecological modelling. We found that environmental variables representing proximity to cover, measures of vegetation and proximity to watercourses are important predictors of burrow presence. Extrapolation of habitat models identified an abundance of habitat suitable for burrows. However, burrows in many suitable areas were abandoned. Our estimate of the population size was similar to the total annual mortality associated with road-kill. Theoretically, given the availability of suitable habitat, common wombat populations in the region should be thriving. It seems likely that this area once supported a much higher number of wombats; however limiting factors such as road mortality and disease have reduced the populations. The persistence of wombats in the study region must be supported by migration from other populations. Our findings challenge the perception that wombats are currently common and not in need of monitoring, suggesting that perceptions of abundance are often clouded by socio-political motives rather than informed by biological and ecological factors. © 2007 Elsevier Ltd. All rights reserved

Using endemism to assess representation of protected areas - the family Myrtaceae in the Greater Blue Mountains World Heritage Area

Aim: We assess how much of species' ranges are present within protected areas and how different land units within protected areas contribute to overall protection, both within their region and at continental scales. We do this using the plant family Myrtaceae in relation to the globally important Greater Blue Mountains World Heritage Area (GBMWHA) in New South Wales, Australia. Location: South-eastern Australia. Methods: Compiling data throughout the region and nationally, we considered two spatially based quantitative measures of endemism (relative range restriction): weighted endemism (WE) and corrected weighted endemism (CWE). In both measures, species are weighted by the proportion of their ranges found within the analysis window, with the ranges calculated as the total number of cells in which they occur (10 km × 10 km in this research). We also derived a novel expectation for the contribution of each species to the endemism scores at each taxonomic level based on the additive properties of the metrics and their relationship to species richness. We used this expectation to assess the proportional contribution of each genus to the endemism scores. Results: The degree to which Myrtaceae species within the GBMWHA are endemic to the GBMWHA area is 16%, meaning that an average of 16% of the ranges of species found in the GBMWHA are restricted to that area. The figure for those species with ranges less than or equal to the median (80 cells) is 33%. The genus Eucalyptus contributes the most to the endemism scores obtained, but no more than would be expected given its number of species. The genus Leptospermum is 3.7% less restricted to the GBMWHA than would be expected, while the genus Melaleuca is 5% more restricted than expected. Main conclusions: Centres of high endemism within the GBMWHA and surrounds were identified. This research presents a template for quantifying endemism for regions at local to global scales. Spatially-based quantitative measures of endemism, such as outlined here, are an important means to quantify and visualize these aspects of conservation significance for the management of protected areas. © 2012 Blackwell Publishing Ltd

Incorporating a distance cost in systematic reserve design

The selection of parcels of land to incorporate into reserve systems necessitates trade-offs among biodiversity targets, costs such as land area and spatial compactness. There are well-established systematic reserve design algorithms that incorporate these trade-offs to assist decision-makers in this process. One cost that has received little attention is the proximity of new land parcels to the existing reserve network: the ability of environmental managers to effectively maintain and protect additional land units is often constrained by their proximity to existing reserve networks. The selection of parcels of land close to existing reserves makes them logistically easier to deploy infrastructure to and can also improve the spatial contiguity of the existing reserve network. Previous research has been limited to using distance from the centroids of existing reserves, which significantly biases algorithms when reserves are irregularly shaped. Here we describe a new approach that overcomes this limitation by using the existing reserve boundary to determine proximity. We provide an example of this approach by implementing it as an additional constraint in an analysis of biodiversity targets within the Greater Blue Mountains World Heritage Area, Australia, via the Marxan reserve design software. The incorporation of the distance cost in the analysis was effective in selecting parcels near to the existing reserve system and can be combined with other variables in the algorithm to improve spatial compactness while meeting biodiversity and other targets. It provides alternative solutions for use by reserve planners when extending reserve systems. © 2011 Taylor & Francis