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.

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)

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Successful biological invasions take place when species introduced to regions outside their natural dispersal range overcome several barriers and establish, persist, proliferate and spread potentially resulting in major threats to biodiversity. The success of invasive alien plants depends on species-specific traits and characteristics of the introduced environment. In this thesis I explore which species traits are important and which environmental barriers need to be overcome for an invasion to occur using Proteaceae as a test case. Firstly, I assessed the global introduction history and invasion ecology of Proteaceae - a large plant family with many taxa that have been widely disseminated by humans, but with few known invaders. This revealed that at least 402 species (i.e. 24% of 1674 species in this family) are known to have been moved by humans out of their native ranges, 58 species (14%) have become naturalized and 8 species (2%) are invasive. The probability of naturalization was greatest for species with large native range sizes, low susceptibility to Phytophthora root-rot disease, larger seeds, mammal-dispersed seeds and those with the capacity to resprout after fire or other disturbances. The probability of naturalized species becoming invasive was greater for species with larger range sizes, species used as barrier plants, taller species, species with smaller seeds, serotinous species, and those that regenerated mainly through re-seeding. Secondly, I looked at mechanisms underlying naturalization on a regional scale, using species which are not already classified as major invaders. At least 26 non-native Proteaceae species have been introduced to, and are cultivated in, South Africa. Propagule pressure facilitated the naturalization of Hakea salicifolia populations in climatically suitable areas, but in suboptimal climates human-mediated land disturbance and land management activities are important for naturalization. Similar drivers are important for naturalization of other alien Proteaceae: a long residence time, fire regimes, poor land management, and propagule pressure were important mechanisms for naturalization. Thirdly, I determined whether reproduction, which in part drives propagule pressure, serves as a barrier for naturalization. I examined several Australian Proteaceae species introduced to South Africa and observed that all species were heavily utilized by native nectar-feeding birds and insects. The five Banksia species that were assessed are self-compatible but four species have a significantly higher reproductive output when pollinators visit inflorescences. Fruit production in H. salicifolia does not differ between naturally-pollinated and autonomously-fertilized flowers. Moreover, no significant difference in fruit production was observed between the five pollination treatments (i.e. natural, pollen-supplementation, autonomous, hand-selfed and hand-crossed treatments) and naturalized and non-naturalized populations. However, pollen limitation was detected in non-naturalized populations which received fewer pollinator visits than naturalized populations. Thus, reproduction limits but is not a fundamental barrier to invasion for H. salicifolia. I conclude that reproductive success of the studied Proteaceae, which is a key barrier determining invasiveness, is not limited by autonomous seed set or mutualisms in the introduced range. In this thesis I highlight biogeographical characteristics, a set of life-history traits and ecological traits as important determinants of invasiveness. These traits are in turn dependent on the stage of invasion. Characteristics of the recipient environment are also important drivers of invasions. This study provides a better understanding of plant invasions in general, but the patterns and processes of invasions highlighted in this thesis will be particularly useful for the current and future management of alien Proteaceae in South Africa and elsewhere, as well as, other species that are adapted to Mediterranean and nutrient poor ecosystems. For example, combining traits of invasiveness and susceptible environments will help to identify which non-native species pose a high risk of becoming invasive (e.g. species with large home ranges and barrier plants) and which conditions in the target area are likely to facilitate or exacerbate invasions (e.g. strong climate match and high propagule pressure). / AFRIKAANSE OPSOMMING: Suksesvolle biologiese indringing vind plaas wanneer ʼn spesie geïntroduseer word in ʼn area buite sy natuurlike verspreidings area, sekere versperrings oorkom, vestig, bly voortbestaan, vermenigvuldig en versprei en potensieel ʼn groot bedreiging inhou vir biodiversiteit. Die sukses van uitheemse indringer plante hang af van spesifieke kenmerke van die spesie en kenmerke van die omgewing waarin dit geïntroduseer word. In hierdie tesis maak ek gebruik van Proteaceae om te ondersoek watter kenmerke is belangrik en watter omgewing versperrings moet oorkom word vir indringing om plaas te vind. Ten eerste assesseer ek die wêreldwye introduksie geskiedenis en indringers ekologie van Proteaceae – ʼn groot plant familie wat wyd gebruik word deur mense, maar met min indringer spesies. Dit het gewys dat mense ten minste 402 spesies (dus 24% van die 1674 spesies in die familie) uit die inheemse areas verskuif het, 58 spesies (14%) genaturaliseer het en 8 spesies (2%) indringers geword het. Die moontlikheid van naturalisasie was die grootste vir spesies met ʼn groot inheemse streek, lae vatbaarheid vir Phytophthora wortelvrot, groter sade, dier verspreide sade en die met ʼn vermoë om weer uit te spruit na ʼn vuur of ander versteuring. Die moontlikheid van genaturaliseerde spesies om indringers te word, was groter vir spesies met groter streek grootte, spesies wat as versperring plante gebruik word, hoër spesies, spesies met kleiner sade, serotiniese spesies, en die wat hoofsaaklik voortbestaan as saadspruiters. Tweedens, het ek gekyk na onderliggende meganismes op ʼn regionale skaal, deur gebruik te maak van spesies wat nie alreeds as belangrike indringers geklassifiseer is nie. Ten minste 26 nie-inheemse Proteaceae spesies is alreeds geïntroduseer en word gekultiveer in Suid Afrika. Propaguul druk fasiliteer die naturalisering van Hakea salicifolia populasies in areas met geskikte klimaat, terwyl in areas met ʼn sub optimale klimaat, versteurings deur mense en grond bestuurs aktiwiteite belangrik is vir naturalisering. Die selfde drywers is belangrik vir die naturalisering van ander uitheemse Proteaceae: lang verblyftyd, vuur bestel, swak land bestuur en propaguul druk. Derdens het ek bepaal of reproduksie, wat gedeeltelik propaguul druk dryf, ʼn versperring is vir naturalisasie. Ek het gekyk na verskeie Australiese Proteaceae spesies wat geïntroduseer is in Suid Afrika, en het gevind dat al die spesies besoek word deur inheemse nektar etende voëls en insekte. Die vyf Banksia spesies wat geassesseer is, kan self bestuif, maar vier van die spesies het ʼn betekenisvolle hoër reproduksie wanneer bloeiwyses deur bestuiwers besoek word. Vrug produksie verskil nie tussen natuurlik bestuifde en self bestuifde blomme in H. salicifolia nie. Verder was daar geen verskil tussen vrug produksie van die vyf bestuiwings behandelinge (naamlik: natuurlik, stuifmeel bygevoeg, self, hand self en hand kruis) en tussen genaturaliseerde en nie genaturaliseerde populasies. Ewenwel, stuifmeel beperking is gevind in nie-genaturaliseerde populasies wat egter ook minder besoeke ontvang het dan die genaturaliseerde populasies. Dus, reproduksie kan die verspreiding beperk maar is nie ʼn fundamentele versperring vir indringing van H. salicifolia nie. My konklusies is dat die reproduktiewe sukses, wat andersins ʼn sleutel versperring is vir indringing, in die bestudeerde Proteaceae nie beperk word deur outonomiese saad produksie of mutualismes in die geïntroduseerde gebied nie. In hierdie tesis beklemtoon ek die biogeografiese karakters, lewens geskiedenis kenmerke en ekologiese kenmerke as belangrike bepalers van indringing. Hierdie kenmerke is op hulle beurt weer afhanklik van die stadium van indringing. Karakters van die ontvangende omgewing is ook belangrike dryfvere van indringing. Hierdie studie verbeter hoe ons plant indringing in die algemeen verstaan, maar die patrone en prosesse van indringing wat beklemtoon word in hierdie tesis sal besonder bruikbaar wees vir huidige en toekomstige bestuur van uitheemse Proteaceae in Suid Afrika en op ander plekke, asook vir ander spesies wat aangepas is tot Mediterreense en nutriënt arm ekosisteme. Byvoorbeeld, die kombinasie van kenmerke van indringing en vatbare omgewings sal help om te identifiseer watter uitheemse spesies ʼn hoë risiko inhou om ʼn indringer te word (byvoorbeeld spesies met ʼn groot streek grootte en versperring spesies) en watter kondisies in die teiken area die waarskynlikste indringing fasiliteer of vererger (byvoorbeeld sterk klimaat ooreenstemming en hoë propaguul druk).

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: I investigated the impacts of the invasive wattle species (Acacia mearnsii, A. dealbata, A. decurrens), on the ecological function and productivity of rangelands in South Africa and their ability to sustain livestock production. More specifically, this study set out to: (1) assess grazing areas at a national scale; (2) identify evidence of progressive impacts of these species on livestock production across a selection of magisterial districts; (3) determine the effects of A. mearnsii density on growth form dominance of indigenous plant species, and highlight how this translates into impacts in forage quality and quantity; (4) determine the effects of A. mearnsii invasion on soil resources and conditions (key determinates of ecological function) required to support grazing production; and finally (5) determine to effects that clearing operations have had on the provision of grazing resources. My results indicate that the level of overlap between wattle invasion and areas with a high grazing potential, at the national scale, is relatively low (2.9%). However, at a magisterial district scale, areas with a high grazing potential have a moderate (approximately 35.1% high grazing potential area under wattle invasion for highest invaded district) level of invasion. Scattered and moderate levels of invasion currently dominate or characterise these species invasion patterns. Both light and dense A. mearnsii invasions reduce grazing capacity. Dense invasion had the most severe effect reducing grazing capacity from 2 ha, required to support one large stock unit, to 8 ha. The clearing of this species was found to improve grazing capacity within 5 years. The reduction in grazing capacity following invasion was largely due to reduced basal cover and herbaceous biomass. The clearing of invaded sites was found to increase both basal cover and herbaceous biomass to pre-invasion levels. Acacia mearnsii invasion was found to affect certain soil properties. Under an A. mearnsii canopy, plant litter, carbon content of the soil and nitrogen concentrations were all found to be elevated. Overall, this study demonstrates that Acacia invasions have a significant effect on grazing resources at a local or site scale, and that for the eastern region of South Africa, these effects are ultimately scaled up to a district level. This is likely to have important financial and human well-being repercussions. However clearing and restoration programs are clearly able to reverse or mitigate these effects. This study therefore lends support to or complements other ecosystem service provision arguments for clearing alien invasive species. / AFRIKAANSE OPSOMMING: Die impak van die indringer- wattelbome spesies ( A. mearnsii , A. dealbata , A. decurrens) , op die ekologiese funksie en produktiwiteit van weivelde in Suid-Afrika en hul vermoë om vee produksie te onderhou was ondersoek. Meer spesifiek, is hierdie studie uiteengesit om: (1) ondersoek in te stel na die mate van oorvleueling tussen indringing deur wattelbome spesies en belangrike weidingsgebiede op 'n nasionale skaal; (2) bewyse te verskaf van die progressiewe impak van hierdie spesies op vee-produksie oor 'n seleksie van politieke distrikte, (3) die gevolge van A. mearnsii digtheid op groei vorm en oorheersing van inheemse plante te wys, en hoe dit voer kwaliteit en kwantiteit affekteer; (4) die gevolge van A. mearnsii indringing op grond hulpbronne sowel as die kondisie (sleutel bepalende faktore van ekologiese funksie) wat benodig word om weiding produksie te ondersteun vas te stel, en uiteindelik (5) om die gevolge van skoonmaak bedrywighede op die voorsiening van weiding hulpbronne te bepaaal. My resultate dui daarop dat die vlak van oorvleueling tussen die wattelbome indringing en gebiede met 'n hoë weiding potensiaal, by die nasionale skaal, relatief laag is (2’9 %). Maar op 'n landdrosdistrik skaal, het gebiede met 'n hoë weiding potensiaal 'n matige (ongeveer 35.1 % weiding potensiaal area onder wattelbome indringing vir die hoogste binnegevalde distrik ) vlak van indringing. Verspreide en matige vlakke van indringing oorheers tans of kenmerk hierdie spesies se indringings patrone. Beide lig en digte A. mearnsii besettings verminder dravermoë. Digte inval het die mees ernstige uitwerking en verminder dravermoë van 2 ha, wat nodig is om een grootvee-eenheid te ondersteun na 8 ha. Bevindinge wys dat die verwydering van hierdie spesies weiding kapasiteit kan verbeter binne 'n tydperk van 5 jaar. Die afname in dravermoë na indringing is grootliks te wyte aan die afname in basale bedekking en kruidagtige biomassa. Na die skoonmaak van indringer persele is bevind dat beide basale bedekking en biomassa weer verhoog tot voor- indringings vlakke. Acacia mearnsii indringing beïnvloed sekere grondeienskappe. Onder A. mearnsii blaredak, is alle blaarafval, koolstof-inhoud van die grond en stikstof konsentrasies verhef. In die algeheel, toon hierdie studie dat die Acacia indringings 'n beduidende uitwerking op weidings hulpbronne by 'n plaaslike of perseel skaal het, en vir die oostelike streek van Suid-Afrika, is hierdie effekte ook uiteindelik vertaalbaar tot 'n distrik vlak. Dit sal waarskynlik belangrike finansiële en menslike welsyn gevolge hê, maar die skoonmaak en herstel programme is duidelik daartoe instaat om die gevolge te keer of te verminder. Hierdie studie leen dus ondersteuning aan of komplimenteer ander ekostelsel dienslewering argumente (soos dié van die Werk vir Water program) vir die verwydering van indringerspesies.

published_or_final_version / Social Work / Master / Master of Philosophy

Investigations were carried out into the allelopathic potential of the invasive alien annual Himalayan Balsam (Impatiens glandulifera Royle) using a series of bioassays, including ones developed or adapted for this study. They were evaluated for their suitability to detect three of the four main modes of allelochemical release, namely leaching, exudation and decomposition. Assays which involved the measurement of lettuce radicles and hypocotyls gave reliable results and allowed a range of different Impatiens material, both living and dead, to be assessed and ranked according to the allelopathic effects demonstrated. Attempts were made to isolate resource competition from allelopathy using separately grown but connected donor and receiver plants and a density dependent design where single I. glandulifera plants were grown in pots with variable numbers of receiver plants. Results proved inconclusive. Initial experiments showed that the allelopathic potential of I. glandulifera varied according to the organ from which the material was derived. Pods, leaves and stems produced the greatest inhibition of lettuce seedlings. Effects on germination were not significant at most of the concentrations tested. Live roots of I. glandulifera plants produced pronounced orange staining of the agar into which they were placed and showed clear evidence of distance dependent inhibition of lettuce radicles. Effects were limited to growth rather than germination of the test plants. Germinating I. glandulifera seeds caused a significant inhibition of lettuce radicle elongation when the two species were grown together in an agar medium. The inhibitory effects increased significantly with increasing exposure time. Increasing I. glandulifera seedling number also produced significant reductions in lettuce radicle length. Dormant seeds, by contrast, stimulated growth. Dead seeds did not produce significant changes to the growth of the test plants. When rhizosphere soil was gathered from pot grown I. glandulifera plants, the results were mixed. Initial samples inhibited growth, whereas those collected from dying plants over a period of weeks stimulated growth. Further experimentation is required before the indications of allelopathic interactions demonstrated here can be applied to the behaviour of wild populations of I. glandulifera.

The proportionality principle and the deprivation of liberty of a foreigner in administrative law This thesis concerns the proportionality of the deprivation of liberty of the foreigner in Czech Republic. It only covers those types of deprivation of liberty that are specifically applied on foreigners and that are covered by the administrative law. In the first chapter this thesis defines legal concepts of a personal freedom and a proportionality principle. The second chapter covers the level of the international law, namely the article 5 of the European Convention of Human Rights, define legal conditions that a deprivation of liberty must meet and offers a relevant judicature of the European Court of Human Rights. The third chapter covers a deprivation of liberty from a view of the Return Directive (No. 2008/115/EC), the Reception Conditions Directive (No. 2013/33/EU) and the Dublin Regulation (No. 604/2013) and offers judicature of the Court of Justice of the European Union. The fourth chapter comprehends the Czech law and covers three acts, that enable a deprivation of liberty of a foreigner - the Act on the Police of the Czech Republic No. 273/2008 Coll., the Asylum Act No. 325/1999 Coll. and the on the Residence of the Foreign Nationals in the Czech Republic No. 326/1999 Coll. This chapter also...

Philosophiae Doctor - PhD / The Cape Floristic Region (CFR) of southern Africa is one of the world’s most unique biodiversity hotspots. However, this biodiversity continues to be threatened by habitat loss due to rapid urbanisation, agriculture and alien vegetation encroachment, and now, by future groundwater extraction and climate change. Previous work had shown that soil moisture is important in structuring wetland plant communities at fine-scale. What is not fully known, however, is how the spatial distribution of species at a local scale is related to soil hydrology and what the response in the future of species distributions will be to perturbations arising from changes in climate or subsurface moisture in the future. The current research investigated the water regime of the Restionaceae which is a key family in the Fynbos biome and the implications of possible changes in soil hydrology caused by climate change in communities within this region. The Restionaceae were particularly appropriate because they are shallow rooted perennials with the ability to tolerate a wide range of water regimes which allows them to successfully co-habit within mixed plant communities as segregated clusters along fine-scale hydrologic gradients. Vegetation survey counts for the presence of these species along with measurements of soil water table depth and moisture content data generated from eight small-scale plots (50 x 50 m) were used to investigate the possible hydrological niches and to envision the potential impacts of a substantial reduction in rainfall and an increase in temperature as projected by Global Climate Models (GCMs) on the structure of Restionaceae communities in seasonal wetlands by 2100. A comparative analysis of the effects of two extreme Representative Concentration emission Pathways (RCP2.6 and RCP8.5) on significant hydrological variables to plant water regimes was carried out. The IPCC AR5 report describes the RCP8.5 emissions scenario as the likely ‘business as usual’ scenario where emissions continue to rise through the 21st century while the RCP2.6 scenario assumes that emissions peak between 2010 and 2020 and substantially subside thereafter.

This dissertation explores the experiences and perspectives of unaccompanied migrant children in Johannesburg South Africa. The children are between the ages of thirteen to nineteen and are all from Zimbabwe. The research focuses on how the young immigrants undertook their journey managing to find ways around the spaces and people they met along the way. The research demonstrates how the vulnerability which research participants feel was not constant. It oscillated depending primarily on spaces and social relationships which children encountered. Through ethnography and the life history approach, the daily experiences of the young people are looked at to provide an understanding of the way they dealt and are still dealing with their vulnerability. The intention being to show that vulnerability is always shifting and being shifted by young people.

Worker. Trade Agent. Serf. Etain Ixtii detests the labels others give her, but there are some things she must accept. She was genetically designed to do specific tasks. Her breeding instincts interrupt her life every forty-five days. But workers like Etain are taught not to question so when she returns from training questioning her home world Gno's profit-based caste system, she risks her life. She doesn't want to be an agent and doesn't want to cross through the wormhole to never return. Why does she have to go? Can't someone else? Usurer Serria, the owner of Etain's birth and training debt, quickly tires of her problem worker and launches Etain through a collapsing wormhole so she can collect the insurance payout. Very bad business indeed, but Etain manages to survive the attempt, arriving on the other side plagued by debilitating headaches and hounded by a dangerous insectoid enemy that no one, including Physician Leigheas Sternbow, the Takla royal physician, and Mercine Feney, the Empire's powerful female leader, can make disappear. / https://dc.etsu.edu/alumni_books/1028/thumbnail.jpg