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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Weeds, people and contested places : selected themes from the history of New Zealanders and their weeds 1770-1940

Clayton, Neil, n/a January 2007 (has links)
This study examines three basic questions. Why did so many familiar floral species with which agricultural people have more or less successfully contested places for some 10,000 years apparently become highly problematic in New Zealand? How did those in whom the developing contest aroused considerable anxiety try to solve the problems they saw emerging? And what were the outcomes of their chosen courses of action? This study is organised around three main themes, science, the law and agricultural practices. Within each theme I take into consideration the ways New Zealanders used particular aspects of these broad disciplines to try to identify, understand and solve the problems they perceived to have been caused by their weedy biota. I also consider the extent to which recourse to these means has helped or hindered the ends they sought. The methodology adopted for this study is a variation of an 'organisational approach', advocated by the German environmental historian Frank Uekoetter. It focuses on the ways responses to perceived environmental problems are organised within a society. From my use of Uekoetter�s model I conclude that, despite a number of setbacks during the mid to late 19th century, by 1939 New Zealanders had developed highly dynamic processes within their weed science, extending into the wider farming community, by which they could feel their way with some confidence into a future where they might better manage the contest with their weeds, if not actually eradicate them.
212

Alternatives to soil fumigation with methyl bromide for the management of soil-borne pathogens in vegetables

Ashley, M. Unknown Date (has links)
No description available.
213

The biology of parthenium hysterophorus L. in Australia

Navie, S. Unknown Date (has links)
No description available.
214

Predicting and preventing the spread of lantana into the Blue Mountains

Gold, Daniel Alexander, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2009 (has links)
Invasive weeds inflict significant harm on native species, ecosystem processes, and natural disturbance regimes. When managing these weed threats, some of the most useful tools are the outputs of predictive distribution models. As they supplement existing distribution data to assess where in the landscape is most susceptible to weed invasion, they allow for more efficient weed management because the areas most suited to weed species may be targeted for control. This research develops a habitat suitability model for the weed lantana (Lantana camara L. sensu lato) in a portion of the Greater Blue Mountains World Heritage Area at present and under forecast warmer climates. A generalised additive model (GAM) is used, which fits the regression curve used for prediction to the calibration data themselves and allows for an exploration of which environmental conditions favour lantana as well as where in the landscape is most suitable for the weed. Temperature was positively correlated with suitable habitat and explained over 90% of the variation in lantana presence predicted by the model. 15% of the study area was found to be suitable for lantana at present, with this figure reaching 58% after a simulated 3??C rise in temperature. Mapping habitat suitability across the study area allowed for the identification of five distinct pathways for lantana to further invade the Blue Mountains. Responding to calls for the integration of weed management with biodiversity conservation, the research also integrates the habitat suitability model with information regarding the distribution of vegetation communities and endangered species in the Blue Mountains. Thirteen native vegetation communities were found to have more than 20% suitable habitat for lantana at present, and an additional three contained more than 80% suitable habitat after a simulated 3??C rise in temperature. Five of these communities are listed as threatened under relevant legislation and harbour at least 27 endangered species, placing additional urgency on their conservation. This research has successfully used modelling techniques to identify areas for targeted weed management integrated with biodiversity conservation. The methods are easily adaptable to other weeds and regions and could thus be used to illustrate the comprehensive threat weeds pose to Australia???s biodiversity.
215

Ecology of wild radish (Raphanus raphanistrum) : crop-weed competition and seed dormancy.

Eslami, Seyed Vahid January 2006 (has links)
Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / Field experiments investigating the nature and extent of interference in monocultures and mixtures of wild radish and wheat were conducted in 2003 and 2004 at Roseworthy, South Australia. Intraspecific and interspecific interfenernce between wild radish and wheat was investigated in the field using additive series design. Results indicated that higher densities of wheat were able to suppress seed production of this weed species. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1274618 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2006
216

Alternatives to soil fumigation with methyl bromide for the management of soil-borne pathogens in vegetables

Ashley, M. Unknown Date (has links)
No description available.
217

Alternatives to soil fumigation with methyl bromide for the management of soil-borne pathogens in vegetables

Ashley, M. Unknown Date (has links)
No description available.
218

Alternatives to soil fumigation with methyl bromide for the management of soil-borne pathogens in vegetables

Ashley, M. Unknown Date (has links)
No description available.
219

Alternatives to soil fumigation with methyl bromide for the management of soil-borne pathogens in vegetables

Ashley, M. Unknown Date (has links)
No description available.
220

Predicting and preventing the spread of lantana into the Blue Mountains

Gold, Daniel Alexander, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2009 (has links)
Invasive weeds inflict significant harm on native species, ecosystem processes, and natural disturbance regimes. When managing these weed threats, some of the most useful tools are the outputs of predictive distribution models. As they supplement existing distribution data to assess where in the landscape is most susceptible to weed invasion, they allow for more efficient weed management because the areas most suited to weed species may be targeted for control. This research develops a habitat suitability model for the weed lantana (Lantana camara L. sensu lato) in a portion of the Greater Blue Mountains World Heritage Area at present and under forecast warmer climates. A generalised additive model (GAM) is used, which fits the regression curve used for prediction to the calibration data themselves and allows for an exploration of which environmental conditions favour lantana as well as where in the landscape is most suitable for the weed. Temperature was positively correlated with suitable habitat and explained over 90% of the variation in lantana presence predicted by the model. 15% of the study area was found to be suitable for lantana at present, with this figure reaching 58% after a simulated 3??C rise in temperature. Mapping habitat suitability across the study area allowed for the identification of five distinct pathways for lantana to further invade the Blue Mountains. Responding to calls for the integration of weed management with biodiversity conservation, the research also integrates the habitat suitability model with information regarding the distribution of vegetation communities and endangered species in the Blue Mountains. Thirteen native vegetation communities were found to have more than 20% suitable habitat for lantana at present, and an additional three contained more than 80% suitable habitat after a simulated 3??C rise in temperature. Five of these communities are listed as threatened under relevant legislation and harbour at least 27 endangered species, placing additional urgency on their conservation. This research has successfully used modelling techniques to identify areas for targeted weed management integrated with biodiversity conservation. The methods are easily adaptable to other weeds and regions and could thus be used to illustrate the comprehensive threat weeds pose to Australia???s biodiversity.

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