Thesis (M.A.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The burgeoning problem of alien plant invasions in South Africa necessitates effective decision-making based on an understanding of the complex processes that govern these invasions. Due to the spatial nature of the problem, this study explored the use of Geographic Information Systems and spatial models for predicting the spread of alien vegetation and assessing the effectiveness of clearing strategies. The Spatially Explicit Individual Based Simulation (SEIBS) model was identified as a potentially useful tool for alien plant management. This thesis documents the further investigation and development that was necessary before recommendations could be made regarding the future use of the model. The landscape version of the SEIBS model was adapted to allow for the convenient input and output of spatial data, making it possible to simulate invasions in different areas. An ArcView extension was developed in order to facilitate the pre- and post-processing of the spatial data required and created by the model. Changes were also made to the fire routine of the model. The new version of the model was called Clear. A series of model tests for Pinus pinaster were conducted to assess the sensitivity of the Clear model to spatial resolution, initial spatial fragmentation and heterogeneity. These tests revealed that the model was sensitive to changes in resolution and needed to be reparameterised when using different resolutions. The initial level of fragmentation was shown to have a major influence on the invasion rate. Although greater levels of spatial heterogeneity with respect to vegetation age did not significantly affect the spread rate, it did increase the effectiveness of clearing strategies based on clearing juvenile or sparse vegetation. Based on these tests, it is concluded that the model can be readily applied to different areas, provided the influence of spatial characteristics is understood and accommodated. The Clear model was shown to be a useful tool for evaluating clearing strategies and for investigating invasion rates. It is recommended that the model be introduced to a wider audience, in order to obtain user feedback and further improve the accessibility of the model. / AFRIKAANSE OPSOMMING: Die toenemende probleem van uitheemse indringerplante in Suid Afrika, noodsaak effektiewe besluitneming wat gebaseer is op 'n begrip van die ingewikkelde prosesse wat indringing beheer. As gevolg van die ruimtelike geaardheid van die probleem, is die gebruik van Geografiese Inligtingstelsels en ruimtelike modelle vir die voorspelling van die verspreiding van indringerplante en die evaluasie van die effektiwiteit van opruimingstrategieë in hierdie studie ondersoek. Die Spatially Explicit Individual Based Simulation (SEIBS) model is as 'n moontlike geskikte hulpmiddel vir die bestuur van uitheemse indringerplante geïdentifiseer, alhoewel verdere ondersoeke en ontwikkeling nodig was voordat aanbevelings vir die gebruik van die model gemaak kon word. Vir hierdie studie is die landskapweergawe van die SEIBS model aangepas om die maklike toevoer en afvoer van ruimtelike data te fasiliteer. 'n ArcView uitbreiding is ontwikkel om met die voor- en naprosessering van ruimtelike data, wat deur die model gebruik en geskep is, te fasiliteer. Veranderinge is ook aan die vuur sub-roetine van die module gemaak. Die nuwe weergawe van die model word Clear genoem. 'n Reeks toetse is vir Pinus pinaster gedoen om die sensitiwiteit van die Clear model te toets teenoor ruimtelike resolusie, aanvanklike vlak van versnippering en vlak van heterogeniteit. Vanuit die toetse het dit geblyk dat die model sensitief was ten opsigte van verandering in resolusie en dat die model se parameters verstel moes word wanneer verskillende resolusies gebruik word. Daar is ook gewys dat die die vlak van aanvanklike versnippering 'n groot impak op die verspreidingstempo het. Alhoewel hoër vlakke van ruimtelike heterogeniteit teenoor plantegroei nie 'n merkbare impak op die verspreidingstempo gehad het nie, het dit wel die effektiwiteit van opruiming-strategieë, gebaseer op die opruiming van jong of yl verspreide plante, verbeter. Die gevolgtrekking wat uit die toetse gemaak kan word is dat die model geredelik op verskillende areas toegepas kan word, op die voorwaarde dat die invloed van ruimtelike eienskappe in ag geneem word en in berekening gebring word. Dit word aanbeveel dat die model wyer bekendgestel word om sodoende gebruikersterugvoer te bekom.

The aim of this study was to carry out a research about the invasions of alien species of herpetofauna and their impacts, to present contemporary state of the studies of alien species in Europe, to analyze success of the invasions in terms of their taxonomic groups, to analyze the impacts of successful inavasions, to evaluate the results and suggest the project of appropriate precausions. Database Web of Science, Zoological Records and web browser Google Scholar were used as sources for searching scientific papers. These were the key words: "alien, reptiles/reptilia; alien, amphibians/ambhibia, invasive". The scientific studies which mentioned introduction of alien reptiles and amphibians to Europe were chosen from database. Population which was viable and reproduced repeatedly was considered as the stable population. Eight species from order salamanders, 20 frogs, eight turtles, 23 lizards and 11 snakes were introduced into geografic part of Europe. The most of the introduced species of alien herpetofauna belonged into families: Ranidae, Lacertidae and Emydidae. The most common pathways for introduction of alien species of herpetofauna were: pet trade, intentional release and cargo stowaway. In the future, the restriction of breeding certain problematic species (ban of import Lithobates catesbeianus and Trachemys scripta scripta into the Europe), more thorough controls of cargo transportation and especially information campaign in schools and media could be solution to the issue of introduction of alien species.

>Magister Scientiae - MSc / Invasive alien plants (IAPs) are often reported to use more water than indigenous plants. Inaddition, IAPs have an ability to adapt to harsh environmental conditions and they tend to spread at rapid rates, thereby threatening the country’s water resources, agricultural land, and biodiversity. Much of South Africa is expected to get drier in future due to climate change and the new climatic conditions are also predicted to accelerate the rate at which alien plants will spread. Approximately 10 million hectares are currently estimated to have been invaded by alien plants in South Africa, with an estimated average annual rate of spread of more than 5%. The first objective of this study was to compare the water use by deep rooted tree species which include invasive alien Prosopis (sp) trees and the co-occurring indigenous A. karroo. These trees are growing in a flood plain of a groundwater dependent catchment in the Northern Cape Province. Both species are dependent on groundwater and thus compete with local communities for this resource. The second objective was to determine the sources of water that the trees were using in order to understand the impacts of each species on groundwater resources. Transpiration was measured using the heat ratio method of the heat pulse velocity sap flow technique while the volumetric soil water content was monitored at several depths down the soil profile using automated capacitance soil water content probes. Weather data was collected using an automatic weather station. Stable isotopes of oxygen and hydrogen from plant, soil and groundwater samples were analysed to determine the sources of water used by the trees. Average tree density was approximately 613 stems per hectare for Prosopis compared to about 100 stems per hectare for A. karroo. Comparative measurements of water use shows that the annual stand level transpiration from Prosopis invasions was approximately 353 mm/year while that from A. karroo was only about 137 mm/year. Differences in stand transpiration were a result of the higher plant density for Prosopis than A. karroo. There were no significant differences in the transpiration rates of the two species for trees with a similar transpiring leaf area. Application of a two compartment linear mixing model for the oxygen isotope ratio during the peak transpiration period in summer showedthat Prosopis derived 23% of its water from the unsaturated zone and 77% from the saturated zone. A. karroo on the other hand derived 53% of its water from the unsaturated zone and47% from the saturated zone. Diurnal fluctuations in groundwater levels were strongly related to the transpiration dynamics of both species. This supports the observation that these deep rooted trees have substantial impacts on groundwater at the study site. Root sap flow patterns of Prosopis showed evidence of hydraulic redistribution wherein the groundwater abstracted by the tap roots was deposited in the shallow soil layers by lateral roots. However, the root sap flow patterns of A. karroo growing adjacent to the Prosopis did not show this phenomenon.

In 2006, a baseline survey for the UNEP/GEF-IAS Project was conducted in BFR to assess the status of IAS in the area. Findings indicated that extensive forest parts had severe S. spectabilis encroachment which appeared to interfere with the normal functioning and productivity of the forest. This study was motivated by the magnitude of S. spectabilis invasion in BFR, the level of public and government concern about the invasion, and the magnitude of the IAS problem across East Africa. This study was thus undertaken to address a specific need of the research and capacity building components of the UNEP/GEF-IAS Project. The study1 was carried out to assess the impacts of S. spectabilis invasion on the productivity of BFR and the socio-economic implications on the livelihoods of the dependent stakeholders (local resident population, timber suppliers and the tourism sector). The study used descriptive statistics to assess the levels of awareness of S. spectabilis invasion, perceptions and knowledge of the conservation values of BFR, knowledge on the benefits and costs of living with S. spectabilis and impacts of S. spectabilis on the flow of quantities and revenues from the benefits it generates. The impact on financial profitability and efficiency of timber firms was assessed using Gross margin analysis (GMA) and financial efficiency ratio analysis respectively. The impact on the population structure of chimpanzees was studied using mean differentials and focused group discussions. Results indicate that the level of awareness about S. spectabilis invasion and the knowledge of the conservation values of BFR were high among all the three stakeholder groups. GMA revealed that S. spectabilis invasion increases variable costs in timber production thus reducing profit margins and financial efficiency of timber firms. Alteration of habitat environment occasioned by S. spectabilis invasion was advanced, though with uncertainty, as a possible reason for the difference in chimpanzee numbers between the infested and non infested forest conditions. Like other IAS, S. spectabilis was found to have both benefits and costs though the distribution of the same differs. S. spectabilis can be considered a net benefit to the local dependent communities whereas it may be a net loss to both the timber and tourism sectors. Conflict of interest in S. spectabilis management is discussed and possible solutions suggested. It was recommended that the threat of invasive species should be tackled through a multisectoral approach. / Dissertation (MSc)--University of Pretoria, 2009. / Agricultural Economics, Extension and Rural Development / unrestricted

Alien invasive species pose a great threat to ecosystems and human communities (Richardson & van Wilgen 2004; Hobbs & Humphries 1995). On private lands, there is a need to find institutional, administrative and scientific responses to the alien plant problem that operate beyond the scale imposed by property boundaries (Slocombe 1998; Grumbine 1994). One such response is the development and support of institutions, such as the St Francis Conservancy, that foster cross-boundary management of landscapes (Hurley et al. 2002). This study seeks to promote collective decision-making and collaborative management by private landowners through the development of a resource allocation system for the control of alien invasive plants on the St Francis Conservancy. The conservancy is located in the south-eastern lowlands of the Cape Floristic Region, between the villages of Cape St Francis and Oyster Bay, and is comprised of the properties of multiple landowners. Mutliple Criteria Decision Analysis (MCDA) and Geographical Information Systems (GIS) techniques were integrated to provide a spatially explicit resource allocation system that considered environmental, social and economic concerns. The MCDA technique selected for use was the Analytical Hierarchy Process (AHP). This technique has a record of providing robust, defensible decisions and enabled the resource allocation decision-problem to be decomposed into a hierarchy of objectives, criteria and indicators. Stakeholders participated in the development of the resource allocation system, especially through providing input into the determination of the relative importance of criteria and indicators through the assignment of weights. Various weighting scenarios were presented and these were interpreted into an ii implementation plan. The costs and effort required to clear alien plants were estimated, and obstacles facing the implementation of the plan were identified.

Most invertebrate species are becoming extinct due to habitat loss and alien plant invasions. Hence this study aimed at determining the response of invertebrates to alien and indigenous vegetation within protected areas in the King Sabatha Dalindyebo (KSD) Local Municipality, Eastern Cape, South Africa. Invertebrates were collected using pitfall traps, during 12 sampling occasions from May 2010 to April 2011 numbers of sampling sites. Although the sampling method was adapted to collecting ground dwelling invertebrates, opportunistic flying invertebrates were also collected. A total of 7 flying invertebrate orders, 25 families, 34 species and 248 individuals were attracted to traps while 5 orders, 19 families, 50 species and 1976 individuals of soil surface-dwelling invertebrates were collected. ANOVA test showed no significant differences (p > 0.05) in species richness and abundance across sites for soil surface-dwelling invertebrates. Bray-Curtis similarity measures in PRIMER and correspondence analysis (CA) in CANOCO showed that sampling units with alien invasive plants shared most soil surface-dwelling invertebrate species at ± 75% level of similarity. Sampling unit A from the Mix alien (MA) site shared most species with indigenous vegetation sites. Sampling units from indigenous vegetation sites shared most species at ± 65% level of similarity. Multivariate analysis using CANOCO indicated that certain site variables such litter depth influenced the distribution of soil surface-dwelling invertebrates across sites. The study provided preliminary data and information for promoting invertebrate biodiversity conservation within protected areas (Nduli and Luchaba Nature Reserves) of the KSD Local Municipality. Key words: invertebrates, indigenous vegetation, alien vegetation, Lantana camara, Acacia mearnsii, and Eucalyptus.

Asian women make up the fastest growing category of the world's population of migrant workers. The thesis examines labor and immigration policies of Canada as a host country for Filipino women migrant workers. It also determines how Canada's working environment for Filipino women migrant workers is mapped out. The thesis is anchored on three major concerns. The first is an analysis of the Philippines as a leading labor exporting country. The thesis expounds on the state mechanisms promoting labor exportation and the corresponding problems that ensue. It is argued that a majority of the problems of labor migration from the Philippines can be attributed to the inadequate policies and laws of the government in the 1970s when labor export first flourished. The second area of concern is a situation analysis of the Filipina migrant workers who come to Canada to work as live-in caregivers. This discussion is focused on Canada's general framework of immigration laws, foreign worker policies and the pertinent provincial labor laws of British Columbia. It analyzes how these pieces of legislation have been shaped by Canada's national policies. The thesis argues that Canada's regulations restricting the rights of foreign domestic workers and the marginalization of their social mobility and status reflect the unequal relationship between the host and the sending countries. The third and most important concern is a policy analysis of the Live-In Caregiver Program vis-a-vis migrants' rights and labor issues. The thesis argues that Canada, through the continuation of the Live-In Caregiver Program, provides Filipino domestic workers inequitable working conditions. It is argued that since Canada is an international forerunner in championing human rights, it becomes anachronistic that a cluster of the country's immigration policies continue to advocate indentured form of labor. Canada is in a unique position, both as a traditional immigrants' country and as an international player, to blaze the trail for international recognition of migrant workers' rights. Canada must eliminate the double standards in the Live-In Caregiver Program vis-a-vis the general immigration policies. Therefore, it is argued that in order to maintain the high marks it has been receiving at the international level, Canada must eliminate two requirements of the Live-In Caregiver Program: First, the two-year live-in requirement and second, the temporary migrant status of live-in caregivers upon initial entry to Canada. Live-in work must be optional and not subject to the granting of permanent residence status. To preserve it international reputation, Canada must also make reforms on the international level by ratifying and implementing international conventions. / Law, Peter A. Allard School of / Graduate

An alien who commits a crime with imprisonment in the penalty scale can be expelled from Sweden. In order for deportation to be relevant, the alien must be sentenced to a more severe punishment than a fine. In examining the issue of deportation, the court must also take into account the alien's connection to Swedish society and make an overall assessment where the reasons for and against deportation are weighed against each other. If the alien has resided in Sweden for a longer period of time, special reasons for deportation are required, which provides a very strong protection for the alien.  The legislation on deportation due to crime is sparsely worded and entails ambiguities in many respects. Examples of ambiguities are which factors get into a recidivism risk assessment when there is no previously documented crime and how the factors in the assessment of an alien's connection to Sweden are to be evaluated. The problem with these ambiguities entails difficulties in predicting the outcome of the overall assessment that the court makes when the reasons for and against deportation are weighed against each other. It is reasonable to assume that the ambiguities can also lead to equal cases not being treated equally as the court is given a great deal of room for interpretation in its overall assessment. From a legal security perspective, these circumstances are problematic as legal security is largely based on the law being predictable. In order to remedy the problem, the legislator must take a clearer position and dare to legislate on the issues. Keywords: Alien, crime, deportation, severe punishment, legislation.

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