La télédétection radar a déjà montré son fort potentiel dans la caractérisation des états de surface et des processus hydriques. La connaissance de ces paramètres est d'un intérêt fondamental pour mieux quantifier et prévoir la répartition des pluies ainsi que pour modéliser l'érosion des sols. Plusieurs modèles ont déjà été développés (empiriques, analytiques, numériques) mais présentent encore des limitations dans la compréhension du comportement du signal radar. L'objectif de cette thèse est d'apporter des améliorations dans la modélisation de la rétrodiffusion et la description des sols agricoles nus, à l'aide de mesures terrain et d'images radar SAR. Nous avons considéré un profil d'humidité en introduisant un aspect multicouche et utilisé le modèle IEM. Nous avons montré qu'une humidité constante sur les premiers centimètres de la surface ne reflète pas la réalité terrain. Nous avons ensuite pris en compte les poches d'air présentes dans la structuration du sol en redéfinissant la constante diélectrique par l'introduction d'un composé air/sol. Ces développements ont permis de contribuer à l'amélioration des résultats de la simulation, de mieux comprendre le comportement du signal radar et les variations du coefficient linéaire liant le coefficient de rétrodiffusion à l'humidité du sol. Enfin, nous avons effectué une représentation plus réaliste des sols agricoles en incluant des mottes de terre sur les profils. A partir d'un modèle de diffusion électromagnétique numérique, basé sur la méthode des moments, nous avons étudié leur influence sur le coefficient de rétrodiffusion.

The need for public participation in the development of policies, programmes or actions has been widely accepted by both government and private sectors because of the benefits of such involvement. Involving the public in the development of any policy, programme or action is, however, a daunting task. Public involvement in the development of a policy or action often leads to protest, legal litigation, criticism and delay in carrying out the project. The main objectives of this research are to examine the process of public participation in the Gautrain project and to interrogate how public involvement in the decision-making processes of environmental concerns can be improved. A quantitative study was conducted to describe and explore the process of public participation in the Gautrain environmental impact assessment procedure. The purposive sampling method was used. Thereafter, the data generated was analysed using statistical tools such as charts, tables and the Wilcoxon Mann Whitney U test to examine the similarities and differences in the response patterns of the public and the project proponent. Cronbach alpha statistical methodology was also used to test the reliability of the measurement. The findings are discussed in relation to the objectives of the study and research hypotheses. The results indicate that (1) the public were not involved early enough during the project planning and design phases; (2) adequate information was not provided to the public; and (3) public input does not have much impact on decisionmaking processes. The study does, however, indicate that the process has enhanced the participants’ learning and that the process of participation has improved in recent time as compared to the 2002-2003 periods. The study concludes by providing relevant solutions and recommendations. / Environmental Sciences / M. Sc. (Environmental Management)

Dans le cadre de la mission spatiale SMOS (Soil Moisture and Ocean Salinity), nous présentons dans cette thèse une nouvelle approche numérique de modélisation du calcul de l’émissivité et du coefficient bi-statique de systèmes forestiers sol-litière en Bande L. Le système sol-litière est représenté par deux couches diélectriques 3D comportant des interfaces rugueuses, une démarche qui n’apparait pas actuellement dans la littérature. Nous validons notre approche pour une seule couche en comparant les simulations de l'émissivité avec celles produites par la méthode des moments et des données expérimentales. A partir de ce nouveau modèle, nous évaluons la sensibilité de l’émissivité du système sol-litière en fonction de l’humidité et de la rugosité de la litière. Ce nouveau modèle permettra de créer une base de données synthétiques d’émissivités calculées en fonction de nombreux paramètres qui contribuera à améliorer la prise en compte de la litière dans l'algorithme d’inversion des données de la mission spatiale SMOS. / In the context of the SMOS (Soil Moisture and Ocean Salinity) mission, we present a new numerical modelling approach for calculating the emissivity and bistatic scattering coefficient of the soil-litter system found in forests, at L-band. The soil-litter system is modelled as two 3-dimensional dielectric layers, each with a randomly rough surface, which to our knowledge has not previously been achieved. We investigate the validity of the approach for a single layer by comparing emissivity simulations with results of Method of Moments simulations, and experimental data. We then use the approach to evaluate the sensitivity of the soil-litter system as a function of moisture content and the roughness of the litter layer. The numerical modelling approach which has been developed will allow us in the future to create a synthetic database of the emissivity of the soil-litter system as a function of numerous parameters, which will contribute to validating and improving the inversion algorithm used by the SMOS mission to retrieve soil moisture over forests.

The purpose of this study is to revise the Department of Water Affairs and Forestry's (DWAF's) current Integrated Environmental Management (IEM) procedure and to develop an Environmental Management Framework (EMF), so as to ensure that the environment is considered in a structured, formal manner at each decision-making stage of the projects development business process. The proposed EMF provides process diagrams that align the IBM principles, the environmental assessment and management tools, and the engineering business process with the project life cycle approach for DWAF's water sector functional areas. Key decision-making points are introduced to the business process to ensure that all the specific requirements have been met before continuing to the next engineering stage of the business life cycle. Auditing nodes were identified within the life cycle approach and complement the decision-making points and strengthen the evaluation of environmental compliance and performance. These process diagrams is designed to prompt development planners and implementers to consider the environment at all stages of the business life cycle and practice sound environmental management. The EMF is based on international best practice and follows the Deming model philosophy as well as principles and elements of an environmental management system. The EMF must be an integral part in the way the department conduct its business and not seen as an ad hoc function and the duties of the environmental officer. To conclude, the EMF is the building block and interim management plan for an appropriate environmental management system in the future and the first step towards business excellence for the Department of Water Affairs and Forestry. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2005.

Magister Legum - LLM

The purpose of this study is to revise the Department of Water Affairs and Forestry's (DWAF's) current Integrated Environmental Management (IEM) procedure and to develop an Environmental Management Framework (EMF), so as to ensure that the environment is considered in a structured, formal manner at each decision-making stage of the projects development business process. The proposed EMF provides process diagrams that align the IBM principles, the environmental assessment and management tools, and the engineering business process with the project life cycle approach for DWAF's water sector functional areas. Key decision-making points are introduced to the business process to ensure that all the specific requirements have been met before continuing to the next engineering stage of the business life cycle. Auditing nodes were identified within the life cycle approach and complement the decision-making points and strengthen the evaluation of environmental compliance and performance. These process diagrams is designed to prompt development planners and implementers to consider the environment at all stages of the business life cycle and practice sound environmental management. The EMF is based on international best practice and follows the Deming model philosophy as well as principles and elements of an environmental management system. The EMF must be an integral part in the way the department conduct its business and not seen as an ad hoc function and the duties of the environmental officer. To conclude, the EMF is the building block and interim management plan for an appropriate environmental management system in the future and the first step towards business excellence for the Department of Water Affairs and Forestry. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2005.

Magister Legum - LLM / This study provides an overview of the development of environmental assessment legislation in South Africa since the advent of democracy and critically assesses whether an effective regulatory system is in place. Where necessary and appropriate, the study may include aspects of foreign and international law. This study also aims to provide an overview of the law as it stands by highlighting both the good and bad elements of the law in relation to EIAs and IEMs. It is furthermore aimed at exposing potential grey areas in the law and proposing possible recommendations for improvement

Monitoring is hugely important for musicians in any type of live situation for them to provide a good musical performance, and In-ear Monitoring (IEM) is increasingly popular among both musicians and audio engineers. Despite this, there has been little research on the topic and musicians and audio engineers would benefit from knowing more about the system, to utilize it in the best way possible. Because of the potentially added issues with structure borne sound, the study has chosen to focus on vocalists that use IEM. Through interviews with both Less experienced IEM users and Experienced IEM users, this study aims to find out what issues IEM users experience in live situations. Other than perceived issues, the study investigates how issues evolve with increased experience, comparing the two user groups, what solutions can be found and how an IEM mix should be for a vocalist. Through a Thematic analysis, the study reaches the conclusion that the main issue with the IEM system for vocalists is isolation from the surrounding world, and that the isolation leads to other perceived issues such as worsening the live feeling and obstructing contact with the audience. The study also concludes that there is a clear connection between monitoring and musical performance with poor monitoring leading to worse performance. The main solution observed is habit with the system, good communication between the audio engineers and musicians and an understanding for both sides workflow to increase efficiency in mixing. With this knowledge, further research can be made to increase the understanding for musicians and audio engineers respectively, and audio engineers and musicians can already focus on increasing cooperation.

The study was undertaken to investigate the following: limiting factors faced by the developers in complying with the EIA conditions and to determine whether the various developers comply with the conditions. The study was undertaken by use of questionnaires, site visits, meetings, photographs, group interviews. Trained fields assistants were also used to administer the questionnaires in order to collect data. Data from two sites were collected between 2012 and 2014 and were intentionally collected in order to provide information regarding the implementation of mitigation measures. The collected data was subjected to SAS (statistical software). Chi-square test for independence was performed in order to compare the differences (Snedecor & Cocharen, 1978) between the two sites. Based on the results of the study, it is therefore recommended that competent authorities should consider drafting and supplying follow-up guidelines and these guidelines should also apply to all the relevant role players involved. / Environmental Sciences / M. Sc. (Environmental Management)

Ces travaux de recherche proposent une approche expérimentale pour étudier les capacités de l'imagerie radar basse fréquence pour la détection des zones humides dans le sous-sol des régions arides terrestres et martiennes et la cartographie géologique de leur proche subsurface. En particulier, l'analyse phasimétrique d'images SAR (bande L) de la Dune du Pyla nous a permis de mettre en évidence un comportement particulier de la différence de phase copolaire, lié à la présence d'une zone humide dans la subsurface. Afin d'interpréter et de modéliser ce phénomène, nous avons développé un modèle analytique de diffusion simple, de type IEM, complété par une expression analytique du terme de diffusion par réflexion multiple. Simulant avec succès le phénomène observé, notre modèle confirme que le signal de phase est généré par le profil d'humidité des structures enfouies occasionnant une composante de diffusion par réflexion multiple. Il a également été montré que ce signal de phase copolaire permet la détection d'interfaces humides à des profondeurs plus importantes que celles autorisées par l'analyse des indicateurs radiométriques classiques. Participant au programme Terrestrial Analog to Mars de la NASA, nous avons également travaillé à la définition des performances d'un système SAR orbital en bande P pour la détection d'humidité dans la proche subsurface de la planète Mars, au moyen de la phase radar. Incluant un terme de diffusion de volume, notre précédent modèle IEM montre que la présence d'hétérogénéités dans les premiers mètres de la croûte martienne pourrait altérer les performances de la différence de phase copolaire pour la détection d'humidité en terme de profondeur d'investigation. Néanmoins, nos résultats de simulations indiquent qu'un tel système SAR, exploitant la phase copolaire, autoriserait la détection de l'humidité et son suivi à l'échelle saisonnière jusqu'à des profondeurs de 3 mètres dans les régions présentant un contexte géologique favorable i.e. une faible concentration de diffuseurs de surface et de proche subsurface. Au-delà de la détection d'humidité des sols, nous avons également cherché à mettre en évidence l'apport de l'imagerie radar pour les applications de cartographie d'interfaces géologiques à grande échelle au moyen de systèmes radar orbitaux. L'analyse polarimétrique de données SIR-C/XSAR pour la Mauritanie a permis de montrer le potentiel de l'imagerie radar basse fréquence pour la détection de structures géologiques de surface ainsi que pour la cartographie de la paléo-hydrologie de la proche subsurface en contexte aride. En particulier, nos résultats ont montré que les données polarimétriques fournissent non seulement des éléments d'information sur les mécanismes de diffusion mis en jeu, mais permettent également de différencier les structures de surface par la rugosité qu'elles occasionnent, des structures de subsurface par la diffusion de volume qu'elles génèrent.