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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.
11

Ecology of the naturalisation and geographic distribution of the non-indigenous seed plant species of New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University /

Gatehouse, Hazel A. W. January 2008 (has links)
Thesis (Ph. D.) -- Lincoln University, 2008. / Also available via the World Wide Web.
12

Why are some species invasive? : determining the importance of species traits across three invasion stages and enemy release of southern African native plants in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science at Lincoln University /

Nghidinwa, Kirsti C. January 2009 (has links)
Thesis (M. Sc.) -- Lincoln University, 2009. / Also available via the World Wide Web.
13

Management of Acacia species seed banks in the Table Mountain National Park, Cape Peninsula, South Africa /

Jasson, René January 2005 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
14

Allelopathic interference potential of the alien invader plant Parthenium hysterophorus

Van der Laan, Michael. January 2006 (has links)
Thesis (M.Sc.(Agric.))(Plant Production)--University of Pretoria, 2006. / Includes bibliographical references. Available on the Internet via the World Wide Web.
15

Assessing the values and impacts of invasive alien plants on the livelihoods of rural land-users on the Agulhas Plain, South Africa

De la Fontaine, Samantha 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Invasive alien plants (IAPs) are known for their detrimental impacts on biodiversity and ecosystem goods and services. A substantial body of research has contributed to our understanding of their impacts on ecology. In comparison the socio-economic aspects of IAPs, are not well understood. Additionally, valuation practises have usually excluded the positive and the non-monetary impacts (benefits and uses) that IAPs hold for local livelihoods. Holistic valuation has been regarded as imperative for decision-making and managerial frameworks. A study was conducted in Elim on the southern Cape coast of the Agulhas Plain, South Africa, which aimed to explore the various impacts of IAPs on the livelihoods of rural land-users. Individual qualitative interviews were conducted face to face with landholders (referred to as farmers) (N = 12) and individuals from the economically marginalized community (referred to as marginalized community) (N = 12). The grounded theory approach to data analysis was used and results of the coding method used were displayed by means of superscripts. Results indicate that farmers were aware of broader uses of IAPs although they themselves did not utilise them as extensively as members of the marginalized communities. Invasive alien and problem plants that held value for both land-users were not perceived as being „invasive‟. Invasive alien plants were believed to have detrimental impacts on biodiversity and ecosystems goods and services which support people‟s livelihoods. Alien clearing programmes such as Working for Water (WfW) and LandCare have done much to alleviate the socio-economic burden of unemployment in this marginalized community. Aside from the social development aims set out by WfW (i.e. employment of low-income communities, poverty alleviation and skills training), knock-on social development benefits (e.g. feelings of pride, responsibility and awareness as well as conflict management skills) were also realised by individuals from the marginalized community that were previously employed by the programme. Farmers regarded alien clearing and management as a process that demands excessive time, energy and financial resources. On single occasions it was found that farmers employed methods other than the conventional clearing and management strategies (e.g. livestock that feed on IAPs and giving refuse IAP biomass from clearing and felling to neighbouring poor communities). No clear consensus was reached about regarding alien clearing and management but more support is desired from government. Working for Water relies on private landholders for alien clearing as it is required by law. This study emphasizes that stronger relationships between government and private landholders as well as more substantial incentives to clear IAPs on private land are prerequisites if required outcomes are to be achieved. Educating society at large about the detrimental impacts of IAPs is fundamental. Additionally, informing landholders on effective alien clearing methods and policies and legislation pertaining to it are key activities for the South African government. Finally, clearing and management programmes need to consider the benefits that local land-users obtain from IAPs when prioritising areas for the management of alien vegetation. / AFRIKAANSE OPSOMMING: Uitheemse indringerplante (UIPe) is bekend vir die nadelige gevolge wat hulle vir biodiversiteit en ekosisteem goedere en dienste inhou. ʼn Aansienlike liggaam van navorsing het bygedra tot ons begrip van die impak daarvan op ekologie. In teendeel, die sosio-ekonomiese aspekte van UIPe word egter nie goed verstaan nie. Daarbenewens, evalueringspraktyke het gewoonlik die positiewe en nie-monetêre impakte (voordele en gebruike) wat UIPe vir plaaslike lewensbestaan hou, uitgesluit. Holistiese evaluering word as noodsaaklik beskou vir besluitneming en bestuursraamwerke. ʼn Studie was uitgevoer in Elim op die Suid-Kaapse kus van die Agulhas-vlakte, Suid-Afrika. Die doel was om die verskillende aspekte van UIP impakte op die lewensbestaan van landelike grondgebruikers aan te spreek. Individuele kwalitatiewe onderhoude is van aangesig tot aangesig gevoer met grondeienaars (na wie verwys word as boere) (N = 12) en individue van die ekonomies gemarginaliseerde gemeenskap (na wie verwys word as gemarginaliseerde gemeenskap) (N = 12). Die gegronde teorie metode tot data analise was gebruik en die resultate van die kodering metode is vertoon deur middel van boskrifte. Resultate dui daarop dat boere bewus was van ʼn wyer reeks van gebruike van UIPe alhoewel hulle dit nie so ekstensief benut het soos die lede van die gemarginaliseerde gemeenskappe nie. Uitheemse en probleem plante wat waarde gehou het vir beide landgebruikers,was nie soseer beskou as „indringers‟ nie. Daar was geglo dat UIPe nadelige impakte het op biodiversiteit en ekosisteme goedere en dienste wat mense se lewensbestaan ondersteun. Programme soos Werk vir Water (WvW) en LandCare wat fokus op die uitroeiing van UIPe, het baie gedoen om die sosio-ekonomiese laste as ʼn gevolg van werkloosheid in hierdie gemarginaliseerde gemeenskap te verlig. Benewens die sosiale ontwikkelings doelwitte uiteengesit deur WvW (o.a. indiensneming van lae-inkomste gemeenskappe, armoedeverligting en vaardigheidsopleiding), is daar ook domino-voordele (bv. gevoelens van trots, verantwoordelikheid en bewustheid sowel as konflik bestuursvaardighede) aangaande sosiale ontwikkeling ervaar deur individue van die gemarginaliseerde gemeenskap wat voorheen in diens van die program was. Boere beskou die uitroeiing en bestuur van UIPe as ʼn proses wat oormatige tyd, energie en finansiële hulpbronne vereis. Op enkele geleenthede was dit gevind dat boere gebruik maak van metodes anders as die konvensionele skoonmaak-en bestuurs strategieë (bv. vee wat voed op UIPe en biomassa wat na afloop van skoonmaak aan die naburige arm gemeenskappe gegee word). Geen duidelike konsensus is bereik met betrekking tot die uitroeiing en bestuur van UIP nie, maar meer ondersteuning van die regering word verlang. Werk vir Water maak staat op private grondeienaars vir die uitroeiing van UIPe. Hierdie studie beklemtoon dat sterker verhoudings tussen die regering en private grondeienaars sowel as meer aansienlike aansporings om UIPe op private grond skoon te maak ʼn voorvereiste is as verwagte uitkomste bereik wil word. Opvoeding van die breër gemeenskap oor die nadelige impakte van UIPe is fundamenteel. Om grondeienaars in te lig oor effektiewe UIP verwyderingsmetodes asook beleide en wetgewing met betrekking daartoe, is belangrikste aktiwiteite vir die Suid-Afrikaanse regering. Ten slotte, skoonmaak- en bestuursprogramme moet oorweging skenk aan die voordele wat plaaslike landgebruikers put uit UIPe wanneer daar geprioritiseer word vir gebiede vir die bestuur van indringerplante.
16

Understanding local knowledge and perceptions about invasive alien plants : a case study of the upper Illovu working for water project.

January 2010 (has links)
For decades, South Africa has been heavily infested by invasive alien plants. As a result there is concern over the increasing rate at which the alien plants are replacing indigenous vegetation. Another concern regarding the invasive alien plants is the indirect stress they pose on the environment due to their excessive water consumption. As a result of this, government of South Africa, through the Conservation of Agricultural Resources Acts (43 of 1983) and other environmental legislation, mandates and encourages the removal of invasive alien plants from the landscapes of South Africa. The need for removal of these invasive alien plants led to the formation of the Working for Water Programme (WfW), which is based on a novel approach to environmental management. It contends that the invasion of ecosystems by invasive alien plants could have detrimental effects on water yields from catchment areas, and that employing people to deal with the problem could both protect this vital resource and provide employment and upliftment in poor rural communities. It has been suggested that the supply of information to the public about invasive alien plants is generally poor, to the extent that many people are the causal agents of these plants entering their communities (McNeely 1999). If this lack of awareness is the case, then understanding the drivers of local knowledge which will feed into public awareness is essential to change public perceptions and values surrounding invasive alien plants. It is important to understand local knowledge in order to determine gaps in information transfer and enable them to make decisions that are grounded in local cultural interpretations of place and their environment (Ebohon et al 2000). It is also important to ii understand what the local communities know and what they need to know about these invasive alien plants. This study is premised on developing an understanding of local knowledge and perceptions about invasive alien plants. The assumption is that those involved in the programme would display positive values towards the environment. It is also assumed that those involved in the programme have developed their local/traditional knowledge of invasive alien plants through the educational component of WfW programme. A case study approach of Upper Illovu Working for Water project was adopted. The research was carried out by means of questionnaire interviews. The respondents were drawn from Indaleni community in Richmond, KwaZulu-Natal. Thirty respondents were interviewed and this was inclusive of the field workers, contractors, project manager and people who were not involved in the project but from the same community. Those not involved in the project were used as a control group. Five objectives were utilized to investigate the aim of this study. They were to: a) Determine the respondents’ relationship to, and perceptions of the Upper Illovu WfW project b) Establish the respondents’ understanding and perceptions about the levels of invasive alien plants in the area c) Determine the respondents’ knowledge and perceptions pertaining to prevention of the spread of invasive alien plants iii d) Establish the respondents’ competencies in controlling and managing invasive alien plants and e) Establish the respondents’ perceptions about the project’s ability to deliver on its objectives. The results of this study indicate that most of the respondents were aware of the Upper IIlovu WfW project and its ecological and social upliftment objectives. The pattern of the responses was such that those that did not participate in the project (control group) were for the most part not sure about their responses. Although those who participated in the project displayed better knowledge of issues concerning invasive alien plants, there were many occasions when they failed to provide some responses without being prompted – given clues or examples. To conclude, there was, therefore, a significant knowledge gap about invasive alien plants and information pertaining to them between the two groups. The implications are that those involved with the project must have received some form of information through public awareness about invasive alien plants. That is their traditional knowledge about these invasive plants has been developed by the education from the programme, WfW. But most importantly, the programme remains a key for economic reasons from the perspective of the participants. The need for constant improvement and development of local knowledge regarding these invasive alien plants is important in dealing with their spread and management of their effects on the environment. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
17

Evaluating the effects of invasive alien plants on water availability and usability of lake water in Gauteng Province

Rwizi, Lameck 08 1900 (has links)
The invasion of ecosystems by alien species is a growing threat to the delivery of ecosystem services. This study explored the spatial distribution of water hyacinth in the Benoni Lakes and made analysis of its impact on water availability and usability in order to understand the evolution and its propagation rates. The study used satellite imagery for lake level modelling using Remote Sensing and Geographical Information Systems for calculations of area covered by weeds in each lake from 2002 to 2012.The modelling approach illustrates the potential usefulness in projecting invasive plants under climate change and enabled the quantification of long term changes in aquatic weeds. The results showed that aquatic infestations in lakes may be used as powerful predictors of correlations between plant abundance and climate change. The study therefore informs decision makers to identify areas where invasion is likely to occur and increase surveillance for early invaders. / Environmental Sciences / M. Sc. (Environmental Management)
18

The impact of non-native woody plants on the native herbivorous insect community of northern Delaware

Zuefle, Marion E. January 2006 (has links)
Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: Douglas W. Tallamy, Dept. of Entomology & Wildlife Ecology. Includes bibliographical references.
19

Determining patterns and impacts of multiple forest stressors in Southern Ontario /

Tanentzap, Andrew Joseph. January 2007 (has links)
Thesis (M.Sc.)--York University, 2007. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 114-162). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR32029
20

Shorebird use of smooth cordgrass (Spartina alterniflora) meadows in Willapa Bay, Washington

Parks, Jared R. January 2006 (has links) (PDF)
Thesis (M.E.S.)--Evergreen State College, 2006. / Title from title screen viewed (3/30/2009). Includes bibliographical references (leaves 40-45).

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