Browsing by Author "Lane, Wade Howard"

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    The diversity of ground bryophyte communities along an altitudinal gradient on La Réunion island
    (2011) Lane, Wade Howard; Hedderson, Terry A; Ah-Peng, Claudine; Slingsby, Jasper A
    Aim: To compare the α, β and phylogenetic diversity of the ground bryophyte communities along a tropical altitudinal gradient in order to determine which processes govern these assemblages. Location: La Réunion island (55°39'E; 21 °00'S), in the western Indian Ocean. Methods: The ground bryophyte communities were surveyed along the eastern slope of Piton des Neiges (350 - 3050 m). α, β and phylogenetic diversity along the altitudinal gradient was determined and graphically presented. Results: The α diversity had two distinct peaks at 1150 - 1350 m and at 2750 m, these corresponded to a dominance in liverwort and moss species, respectively. The phylogenetic diversity along the altitudinal gradient was far greater than is predicted from the null models suggesting that ground bryophyte communities are structured according to "environmental filters". The mid-domain effect and mass effect could not be used to describe the changing diversity along the altitudinal gradient, however a correlation analysis revealed temperature and relative humidity influences the changing a diversity. Main Conclusions: In conclusion both ecological and evolutionary processes structure the ground bryophyte communities.
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    Open Access
    Is the grass really greener on the other side?
    (2013) Lane, Wade Howard; February, Edmund C; Woolley, Leigh-Ann
    While many studies focus on identifying pollutants within an ecosystem or how they affect primary producers, few look at how pollutants move through trophic levels or their influence on animal demography. The aim of this study was to determine whether additional nitrogen, phosphorus and water, to a savanna would alter the vegetation quality enough to influence the feeding behaviour and diet of the ungulate populations both of which would alter the vegetation quantity. The study was conducted in the Kruger National Park. One site was supplied with additional nutrients and compared to three control sites. The nitrogen and phosphorus content of grass and tree leaves collected at the enriched site were higher than the leaves collected at the control site, indicating the additional nutrients are improving the vegetation quality. Feeding rates (determined from photos captured by camera traps) indicated a higher degree of herbivory at the enriched site. However, there was no difference in the δ¹³C value, nitrogen and phosphorus content in the ungulate dung collected amongst the study sites suggesting no change in the diet. The dominant grass was significantly shorter at the enriched site suggesting that increased grazing was diminishing grass biomass. Basic assessment of the trees indicated that the additional water at the enriched site seemed to be triggering an earlier start to the growing season for the trees. It was concluded that the additional nutrients have altered the vegetation structure enough to potentially influence animal demographics.