http://hdl.handle.net/10092/23 2013-05-24T02:17:28Z 2013-05-24T02:17:28Z Armstrong, Mark James http://hdl.handle.net/10092/4509 2011-12-07T11:46:10Z 2000-01-01T00:00:00Z

Title: Geomorphological and geophysical investigation of the effects of active tectonic deformation on the hydrogeology of North Culverden Basin, North Canterbury Authors: Armstrong, Mark James Abstract: This thesis examines the complex interaction between the tectonic evolution of Culverden Basin and the Late Quaternary sediments, which form the aquifer-bearing deposits, using geological and geomorphological mapping as well as near-surface geophysical investigations. Along the eastern margin of Culverden Basin, the deformation associated with the actively widening Australian-Pacific plate boundary zone, has resulted in the evolution of Culverden Basin and the progressive inversion of the basin floor. The eastern margin of the basin is structurally controlled by a NE trending, complexly segmented range-front fault system and associated thrust-propagated anticlines forming the basin boundary. Basin inversion is driven by the westward propagation of footwall imbricate thrusts and associated folds. The inversion of the basin floor lead to the creation of sub-basins within the larger basin, which have controlled the distribution and architecture of the Late Quaternary stratigraphy. The Late Quaternary sedimentary record documents periods of climatically induced aggradation during cold conditions and degradation in the intervening warmer times. The interaction between the sedimentation and ongoing tectonic deformation has resulted in complex lithological relationships between the locally sourced alluvial fans and the glacial outwash deposits of the major rivers entering the basin. The architecture of the aquifers is therefore controlled by the changing fluvial regime and its interaction with the evolving sub-basins. The progressive evolution of the sub-basins leads to increasing complexities in the facies relationships and to the confinement of the deposits into progressively smaller portions of the sub-basins. Once the basin boundaries become emergent, the basin becomes isolated, and potentially cut-off from its groundwater recharge source. Leonard Mound is an actively evolving imbricate thrust system along the eastern margin of Culverden Basin that has isolated the Wynyard sub-basin from the central portion of Culverden Basin, during the Late Pleistocene and present. The emergence of Leonard Mound is preventing the recharge to the Wynyard sub-basin from the high yielding aquifers of the central portion of the basin. In the central portion of Culverden Basin, high natural recharge combined with an irrigation scheme has allowed for transformation of the basin into a major dairy farming centre. In contrast, the Wynyard sub-basin is still subjected to frequent summer droughts, making it desirable to find a better source of groundwater for the eastern margin of the basin. The hydrogeological model provided by the Culverden Basin almost certainly has wider implications to the groundwater resources of other basins in similar active tectonic settings.

2000-01-01T00:00:00Z De Bruyn, A. Villemot, J. Lefeuvre, P. Villar, E. Hoareau, M. Harimalala, M. Abdoul-Karime, A.L. Abdou-Chakour, C. Reynaud, B. Harkins, G.W. Varsani, A. Martin, D.P. Lett, J-M. http://hdl.handle.net/10092/7745 2013-05-24T00:06:30Z 2012-01-01T00:00:00Z

Title: East African cassava mosaic-like viruses from Africa to Indian ocean islands: Molecular diversity, evolutionary history and geographical dissemination of a bipartite begomovirus Authors: De Bruyn, A.; Villemot, J.; Lefeuvre, P.; Villar, E.; Hoareau, M.; Harimalala, M.; Abdoul-Karime, A.L.; Abdou-Chakour, C.; Reynaud, B.; Harkins, G.W.; Varsani, A.; Martin, D.P.; Lett, J-M. Abstract: Cassava (Manihot esculenta) is a major food source for over 200 million sub-Saharan Africans. Unfortunately, its cultivation is severely hampered by cassava mosaic disease (CMD). Caused by a complex of bipartite cassava mosaic geminiviruses (CMG) species (Family: Geminivirideae; Genus: Begomovirus) CMD has been widely described throughout Africa and it is apparent that CMGs are expanding their geographical distribution. Determining where and when CMG movements have occurred could help curtail its spread and reveal the ecological and anthropic factors associated with similar viral invasions. We applied Bayesian phylogeographic inference and recombination analyses to available and newly described CMG sequences to reconstruct a plausible history of CMG diversification and migration between Africa and South West Indian Ocean (SWIO) islands.

2012-01-01T00:00:00Z Graham, F.F. White, P.S. Harte, D.J.G. Kingham, S.P. http://hdl.handle.net/10092/7741 2013-05-21T12:30:17Z 2012-01-01T00:00:00Z

Title: Changing epidemiological trends of legionellosis in New Zealand, 1979-2009 Authors: Graham, F.F.; White, P.S.; Harte, D.J.G.; Kingham, S.P. Abstract: This study evaluated the spatio-temporal variation of Legionella spp. in New Zealand using notification and laboratory surveillance data from 1979 to 2009 and analysed the epidemiological trends. To achieve this we focused on changing incidence rates and occurrence of different species over this time. We also examined whether demographic characteristics such as ethnicity may be related to incidence. The annual incidence rate for laboratory-proven cases was 2.5/100 000 and 1.4/100 000 for notified cases. Incidence was highest in the European population and showed large geographical variations between 21 District Health Boards. An important finding of this study is that the predominant Legionella species causing disease in New Zealand differs from that found in other developed countries, with about 30–50% of cases due to L. longbeachae and a similar percentage due to L. pneumophila for any given year. The environmental risk exposure was identified in 420 (52%) cases, of which 58% were attributed to contact with compost; travel was much less significant as a risk factor (6.5%). This suggests that legionellosis has a distinctive epidemiological pattern in New Zealand.

2012-01-01T00:00:00Z Mauger, R. P. http://hdl.handle.net/10092/7735 2013-05-17T12:30:45Z 1943-01-01T00:00:00Z

Title: The constitution of the aldobionic acid from phormium hemicellulose Authors: Mauger, R. P. Abstract: The term “Hemicellulose” is applied to the cell-wall constituents extracted from plant tissues by cold 4% sodium hydroxide, after preliminary extractions with cold water and 0.5% ammonium oxalate to remove pectic substances and water-soluble materials. The originator of the name was Schultze who, in 1891 and succeeding years, isolated there substances from a number of plant materials by extraction with dilute alkali and precipitation with acid. He observed that they were far more susceptible to dilute acid hydrolysis than cellulose, and believed them to be in some way related to cellulose, probably as intermediates in its formation. Although the eludication of the structure of cellulose and the analysis of hemicellulose have shown that there is little foundation for this belief, the name “hemicellulose” still persists. Hemicelluloses are polysaccharides which generally contain uronic acid. One of the few well-authenticated true hexosans that may be removed by alkali from the cell-wall of a higher plant is the mannan of the ivory nut. When dried by alcohol, hemicellulose preparations are obtained as fine, white or cream, amorphous powders; whereas, if dried from water, they form an extremely hard, horny mass, which will redissolve only with difficulty even if finely ground. The hemicelluloses are optically active, and usually more or less strongly laevo-rotatory. The majority of hemicellulose preparations give either no colour or a slightly greenish colour with iodine. The hemicellulose “A” of black-locust and of English oak sap-woods, precipitated by hydrochloric acid, was found to give a strong blue colouration with iodine. Anderson (1940) found that those hemicelluloses which are coloured by iodine solution usually give some d-glucose along with d-xylose in the products of hydrolysis. O’Dwyer suggests that in these hemicelluloses, anhydro-glucose units form a part of the molecule. It is more probable however, that they are derived from starch associated with it.

1943-01-01T00:00:00Z