Konlechner, T.M.; Buckley, E.C.B.; Hilton, M.J., and Wakes, S.J., 2016. Downwind dune dynamics following Ammophila arenaria invasion. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, ...R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 298–302. Coconut Creek (Florida), ISSN 0749-0208. The growth of large foredunes following invasion by non-native plants has been linked to changes in beach-dune sediment transfers, and the deflected evolution of transgressive dune systems. These changes have the potential to alter downwind plant communities by modifying habitats. This paper describes changes to a transgressive dune system in southern New Zealand following invasion by Ammophila arenaria and associated foredune development. Landforms were mapped using aerial imagery from 1958, when A. arenaria was present but not dominant, through to 2013. The landscape downwind of the foredune has evolved from a sparsely vegetated, sandy landscape, dominated by nebkha, to a landscape containing well-defined, long-walled parabolic dunes and stony deflation surfaces. These changes are associated with an increase in deflation surface habitat and plant species diversity, and a corresponding loss of habitat for species associated with dunal areas. The area of deflation surface has increased 18% to 31% of the study area while dune areas decreased from 74% to 51%. These results indicate species associated with transgressive dune systems are sensitive to variations in sand supply and changes in this supply may occur over decadal scales. Land managers are now restoring beach-hinterland sand exchange by destabilizing the foredune and adjacent parabolic dunes to encourage sand drift inland.
Buckley, E.C.B.; Hilton, M.J., Konlechner, T.M., and Lord, J.M., 2016. Downwind sedimentation and habitat development following Ammophila arenaria removal and dune erosion, Mason Bay, New Zealand. ...In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 268–272. Coconut Creek (Florida), ISSN 0749-0208. Since 2002 Ammophila arenaria has been progressively eradicated from a section of the transgressive dune system at Mason Bay, New Zealand to restore dune mobility. This study examines whether sand released from the treatment areas is accumulating in down-wind dune environments, particularly stony deflation surfaces. Deflation surfaces are nationally threatened habitats that contain at-risk native plants and are important flocking sites for endangered shore birds. Sand accumulation in the stonefield may cause a shift in texture and character from deflation lag to sand dunes, potentially reducing habitat for these species. Sediment accumulation was examined over a nine month period within a 200m × 50m plot located immediately downwind of a series of long-walled parabolic dunes, recently destabilised by A. arenaria removal. Sand accumulation was monitored using 500 erosion pins. Digital elevation models were derived from two total station surveys to determine whether sand is accumulating in conjunction with Ficinia spiralis nebkha. Wind speed and direction were measured during wind events to determine whether sand is deposited during these events or whether sand passes through. The surface of the study area accreted 3.22mm, on average, during the study. Accretion and erosion was not strongly correlated with vegetation cover. The intensity of aeolian sedimentation appears to increase with increasing distance inland, because the study site increases in elevation and exposure further inland. Sand pits dug across the area showed medium term sand accumulation aross the study site with most of the accumulation closer to the eroding depositional lobes.
Human-mediated biological exchange has had global social and ecological impacts. In sub-Saharan Africa, several domestic and commensal animals were introduced from Asia in the pre-modern period; ...however, the timing and nature of these introductions remain contentious. One model supports introduction to the eastern African coast after the mid-first millennium CE, while another posits introduction dating back to 3000 BCE. These distinct scenarios have implications for understanding the emergence of long-distance maritime connectivity, and the ecological and economic impacts of introduced species. Resolution of this longstanding debate requires new efforts, given the lack of well-dated fauna from high-precision excavations, and ambiguous osteomorphological identifications. We analysed faunal remains from 22 eastern African sites spanning a wide geographic and chronological range, and applied biomolecular techniques to confirm identifications of two Asian taxa: domestic chicken (Gallus gallus) and black rat (Rattus rattus). Our approach included ancient DNA (aDNA) analysis aided by BLAST-based bioinformatics, Zooarchaeology by Mass Spectrometry (ZooMS) collagen fingerprinting, and direct AMS (accelerator mass spectrometry) radiocarbon dating. Our results support a late, mid-first millennium CE introduction of these species. We discuss the implications of our findings for models of biological exchange, and emphasize the applicability of our approach to tropical areas with poor bone preservation.
Neisseria gonorrhoeae antimicrobial resistance (AMR) is a globally recognized health threat; new strategies are needed to enhance AMR surveillance. The Northern Territory of Australia is unique in ...that 2 different first-line therapies, based primarily on geographic location, are used for gonorrhea treatment. We tested 1,629 N. gonorrhoeae nucleic acid amplification test-positive clinical samples, collected from regions where ceftriaxone plus azithromycin or amoxicillin plus azithromycin are recommended first-line treatments, by using 8 N. gonorrhoeae AMR PCR assays. We compared results with those from routine culture-based surveillance data. PCR data confirmed an absence of ceftriaxone resistance and a low level of azithromycin resistance (0.2%), and that penicillin resistance was <5% in amoxicillin plus azithromycin regions. Rates of ciprofloxacin resistance and penicillinase-producing N. gonorrhoeae were lower when molecular methods were used. Molecular methods to detect N. gonorrhoeae AMR can increase the evidence base for treatment guidelines, particularly in settings where culture-based surveillance is limited.
This two-volume collection, supported by an in-depth introduction that addresses origins, actuality, endgame and afterlife, brings together for the first time contemporary documentation and more ...recent scholarship to give a broad picture of Japan's Treaty Ports and their inhabitants at work and play in the second half of the nineteenth century.
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