[pt] No modelo econômico tradicional, o sistema elétrico podia ser constituído por empresas verticalizadas, isto é, os serviços de geração, transmissão e distribuição podiam ser providos por uma mesma empresa. Nesta estrutura, serviços como reserva de potência, suporte de reativos, reserva de transmissão, ou seja, os chamados Serviços Ancilares à operação do sistema elétrico, não eram computados com custos específicos a serem restituídos, já que os mesmos encontravam-se agregados ao preço da energia elétrica. No novo modelo econômico, onde cada empresa presta um tipo de serviço, é crescente a importância da caracterização de cada Serviço Ancilar. Definidos os prestadores do serviço e usuários, torna-se explícita a necessidade de uma estrutura de mercado para aquisição e revenda do Serviço Ancilar. Este trabalho propõe um mecanismo de mercado para compra e venda de Serviços de Reserva de Potência Operativa por intermédio de um agente de mercado sem fins lucrativos. Este é baseado no mecanismo praticado pelo California Independent System Operator e, devidamente adaptado, pode ser aplicado ao sistema elétrico brasileiro. As principais adaptações são: i) o ajuste da venda para permitir uma distribuição justa da vantagem econômica obtida com a compra considerando os mercados interdependentes, e ii) o ajuste da venda para que os compradores somente das reservas R1 e R2 afetem os preços de R1 e R2, e não os preços de R3 e R4. / [en] In the previous structure of the Brazilian power sector, the economic model was such that the same company could provide generation, transmission and distribution services. In this model, services such as power reserve, reactive power support and transmission reserve, i.e., the so-called Ancillary Services to the operation of the electric system, were not considered explicitly. Therefore, no specific costs had to be paid as they were aggregated to the final energy price. In the new structure of the power sector, where each company provides a different type of service, the distinction of each Ancillary Service becomes a very important issue to the energy business. Once defined the service providers and users, it is evident the need of a market structure for selling and buying the service. This work suggests a market mechanism for selling and buying the Power Operative Reserve Service through a non-profit market agent. This proposal is based on the California`s Independent System Operator mechanism and, if properly adapted, can be applied to the Brazilian Power System. The main adaptations are: i) the adjustments of the sale price to allow a fair distribution of the economic advantage gotten with the purchase considering the interdependent markets, and ii) the adjustments of the sale price for the purchasers of only R1 and R2 reserves to affect only the prices of R1 and R2 and not the prices of R3 and R4. / [es] En el modelo económico tradicional, el sistema eléctrico podía ser constituido por empresas verticalizadas, es decir, los servicios de generación, transmisión y distribuición podían pertenecer a una misma empresa. En esta extructura, servicios como reserva de potencia, soporte de reactivos, reserva de transmisión, o sea, los llamados Servicios Auxiliares a la operación del sistema eléctrico, no eran calculados con costos específicos que serían restituidos, ya que éstos se encontraban agregados al precio de la energía eléctrica. En el nuevo modelo económico, donde cada empresa presta un tipo de servicio, cresce la importáncia de la caracterización de cada Servicio Auxiliar. Una vez definidos los prestadores del servicio y los usuarios, se necesita de una extructura de mercado para adquisición y revenda del Servicio Auxiliar. Este trabajo propone un mecanismo de mercado para compra y venda de Servicios de Reserva de Potencia Operativas por intermedio de un agente de mercado sen fines lucractivos. Este es basado en el mecanismo praticado por el California Independent Systen Operator y, debidamente adaptado, puede ser aplicado al sistema eléctrico brasilero. Las principales adaptaciones son: i) ajuste de la venda para permitir una distribuición justa de la ventaja económica obtenida con la compra considerando los mercados interdependientes, y ii) el ajuste de la venda para que los compradores solamente de las reservas R1 y R2 afecten los precios de R1 y R2, y no los precios de R3 y R4.

The ecology and life history of the vlei rat, Otomys irroratus (Brants, 1827), were studied in a population on the Van Riebeeck Nature Reserve near Pretoria. Two main procedures were used to collect the basic information and material for the project. First, a permanent live-trapping grid was established where 333 animals were captured, marked, released, and recaptured over a period of 26 months, Second, snap-trapping and live-trapping were conducted elsewhere in the study area for supplementary material. Because Otomys angoniensis Wroughton, 1906, a sibling species of 0. irroratus, also occurred in the study area and grid, it was necessary to define the differences in morphology and ecological distribution between the two species. The ecology and life history of 0. irroratus are described and discussed in regard to the following major topics: taxonomy and morphology, distribution, population dynamics, reproduction, postnatal growth and development, activity, behavior, and economic importance. In addition to the presently used means of distinguishing 0. irroratus and 0. angoniensis, it was found that the hind foot length of the two species differed, being 29-34 mm in 0. irroratus and 25-28 mm in O. angoniensis. The baculum of the two species was also found to be distinct in both shape and size. In Southern Africa 0. irroratus occurs primarily in the grassland subregion of the Southern Savanna biotic zone, while O. angoniensis occurs primarily in the woodland subregion of the same biotic zone. The preferred habitats of the two species on the study grid were determined. There was little overlap of niches and each species had a high degree of association with a different veld type, O. irroratus being associated with the more mesic habitat. The population size of O. irroratus reached a peak in May and a low in September. The population also fluctuated considerably from one year to the next, with rainfall possibly being the main contributing cause. The ratio of juveniles, subadults, and adults fluctuated primarily in respect to the season when the young were born. The sex ratio did not depart significantly from 1:1. Males comprised 49,5 per cent of the total and females 50,5 per cent. The rate of disappearance after one month from first capture was 41 per cent, indicating that a large number of transients and individuals dispersing from their birth site were involved. The overall rate of disappearance, excluding the high first month rate of disappearance, was 3,1 per cent per month. The mortality rate appeared to be at its highest between August and September when the food and cover were of very poor quality and quantity. This was also the period when males demonstrated a significant loss in body weight. The major factors causing mortality appeared to be flooding of the habitat and owl predation. Floods not only reduced the population but significantly interrupted breeding. Otomys irroratus was one of the most prominent prey species of both barn and grass owls. The major factors causing mortality appeared to be flooding of the habitat and owl predation. Floods not only reduced the population but significantly interrupted breeding. Otomys irroratus was one of the most prominent prey species of both barn and grass owls. Recapture data revealed that the mean home range size was 1 443m2, while that of males (1 730 m2) was highly significantly different (P<O,Ol) from that of females (1 252m2). Home range size decreased significantly in winter but only slightly in relation to a doubling of the population size. Of 18 individuals recaptured after a flood, 12 (66,7 per cent) had returned to their previously determined home range. Despite a small mean litter size (2,33) and relatively long gestation period (about 40 days), the long breeding season (nine months) and precocial birth, rapid development, and nipple-clinging behavior of the young together give O. irroratus a good reproductive potential. Several litters of young were reared. They are precocial at birth and development proceeds rapidly. At birth the incisors are erupted, enabling the young to cling firmly to the nipples of the mother, thereby reducing mortality losses. Most adult behavior patterns are developed before weaning at 13 days of age. Sexual maturity is reached at approximately three months of age. Otomys irroratus is primarily crepuscular, but activity tests conducted in the field and laboratory indicated some activitv throughout the day and night. Individual and social behavior are described and discussed. The vlei rat is shy and retiring in captivity and in nature is not easily captured by the use of snap-traps. Interactions of adults were tested and they were found to be antisocial, with intrasexual aggression occurring when caged. Complex threat and communication patterns exist, a feature of asocial behavior. Mating failed to occur in captivity, probably as a result of their antisocial nature. Marking behavior is very distinctive and, combined with urination and possibly defecation, would appear to be useful in delineating territories. It would also appear from their social habits, marking behavior, and considerable overlap of home ranges that their interactions with conspecifics in nature are represented by a dominance hierarchy. The influence of O. irroratus upon the environment was found to be slight. The species serves as a common prey item for a number of predators and was found to harbor several endo- and ectoparasites of public health importance. / Thesis (DSc)--University of Pretoria, 1973. / gm2013 / Zoology and Entomology / Unrestricted

M.Sc. (Geography) / This study concentrates. not only on the physical and chemical factors influencing erosion levels in the Pilanesberg area, but also on the impact of anthropogenic factors such as artificial drainage and other cultural irregularities that have modified the local catchment in the Pilanesberg area. For this reason, a comparative study of soil erosion has been made across the perimeter of the Pilanesberg Nature Reserve. The study'aimed to analyze the impact of climatic factors, chemical and physical properties of the soils on the local erosion system. Possible triggering mechanisms of the erosion have been discussed and conservation concerns in the Pilanesberg area have been raised. Of major importance in this study has been the'estimation of soil loss rates across the perimeter of the PNR.. This was premised on the 'rationale that population pressure has an impact on the local erosion system, Through the' analysis of sediment trapped at the monitoring sites it has been possible to indicate the tremendous impact of population pressure on the slopes of the Pilanesberg hills, just outside of the PNR. The rate at which soil is lost on the surrounding rural landscape in the Pilanesberg area has been found to be on average. nearly four times higher than inside of the PNR.

Magister Legum - LLM / South Africa

Namaqualand is a semi-desert area situated in the winter rainfall region of South Africa hosting the world’s richest succulent flora, and is one of only two arid areas to classify as a global hotspot of biodiversity. The Goegap Nature Reserve, east of Springbok, lies in the Upland Succulent Karoo. After all the livestock were removed and the reserve fenced in 1969, a long-term monitoring project was initiated to record possible vegetation changes under the reduced grazing pressure. The first monitoring was done in 1974 when two line transects, of 1 km each, were surveyed. These surveys have been repeated annually covering a period of more than 30 years. When the reserve was enlarged in 1990, five additional line transects were set out in highly degraded areas. The main aim of this study was therefore to determine whether any changes in the vegetation in terms of species composition, species richness and life form richness in the monitored line transects could be detected. Rainfall as possible force driving these changes was also examined. It was found that changes did indeed take place in the vegetation. The species composition revealed notable changes over the entire monitored period, specifically in the two longest established line transects, whereas in the case of the species richness changes were also detected, but to a lesser extent and not notable in terms of an overall increase or decrease in the number of species. These changes are referred to as fluctuations. Rainfall can be regarded as a definite environmental driving force, with the time, intensity and duration of importance, specifically to the annual species composition. Overall, the veld condition improved and continuous monitoring of the line transects on a regular basis should take place to improve our understanding of the complex dynamics of this ecosystem. Because the changes in species composition are reflected in changes in grazing capacity the results are of direct importance to the management of the wildlife on the reserve. / Dissertation (MSc)--University of Pretoria, 2010. / Plant Science / unrestricted

This thesis explores ways in which open space can be made memorable through the application of ecological design and landscape narrative principles. The Faerie Glen Nature Reserve is located in the predominantly residential eastern suburbs of Pretoria and has been identified as an important open space due to its unique ecological sensitivity. The hypothesis argues that through an understanding of the landscape narrative, interventions can be made in the reserve that will not negatively affect the ecological importance or the visual aesthetic of the reserve. These interventions will contribute to making a memorable landscape by reinforcing its beauty and genius loci. The interventions in the reserve should increase the daily use of the Faerie Glen Nature Reserve and thus promote the reserve as a sustainable open space while preserving its ecological importance. Copyright / Dissertation (ML(Prof))--University of Pretoria, 2010. / Architecture / unrestricted

The exact ecological and economic role of lion Panthera leo populations on small enclosed reserves is poorly understood. The management and monitoring of such populations is important to ensure their long-term survival. The prey use, range use and habitat selection of an isolated lion population were investigated. The study was conducted on a small (> 1000km2), enclosed predator camp of Tswalu Kalahari Reserve, situated in the Northern Cape Province of the Republic of South Africa. The prey selection, prey preferences and prey biomass removal were determined by using indirect and direct observations. Kill sites, carcasses and scats were located by spoor tracking and opportunistic observations and collated into a prey selection list. The prey selection was used to determine any prey preferences and the prey biomass removal by the lion population. The scats data was corrected for relative prey biomass and compared to the kill data and uncorrected scat data. 19 prey types were used, with the gemsbok Oryx gazelle and blue wildebeest Connochaetes taurinus being utilized most. The lion population had clear preferences for specific small and large mammals which concurred with other studies done on Kalahari lion behaviour. The prey biomass removal (9.9kg/Lion feeding Unit/day) was higher than several other studies done on lion consumption rates. The range use and habitat selection were determined by using direct and indirect observations. The minimum convex polygon method and kernel density estimates were used to delineate the ranges of the lion population. The mean range size of the Tswalu lions (91 km2) was similar to those found for lions in more mesic environments. The lions also had clear habitat preferences which depended on the habitat preferences of the prey and the prey density. A population viability analysis, using VORTEX 9.72, was conducted. An Ecological capacity was determined and used to model various environmental scenarios. The population was found to be viable, but constant monitoring and updating are needed. Management recommendations for the conservation of lions and their prey are provided. / Dissertation (MSc)--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted

This study analyses the linkage between monetary policy and the stock market in South Africa using monthly data for the period from 2000 to 2010. It provides an overview of the Johannesburg Stock Exchange and the monetary regimes adopted by the South African Reserve Bank since the 1960s and the interrelation between the monetary variables and the stock market. It also provides a review of literature, both theoretical and empirical on the linkages between the two variables. Based on the review of literature, a Vector Autoregression [VAR] model was chosen as a method of analyzing the relationship between the two variables. The empirical results revealed that there is no long term relationship between the variables, however, in the short-run there is a dynamic relationship between monetary policy and the stock market in South Africa. This implies that innovations in the stock market affect the implementation of monetary policy and vice-versa. The study recommended that monetary authorities should pay attention to the fact that the stock market performance has a great impact on their decision making due to the fact it is greatly affected by repo rates.

Antalet med en demenssjukdom ökar i världen och siffran drabbade förväntas stiga till 132 miljoner år 2050. Kartläggning av riskfaktorer är en viktig del av det preventiva arbetet. Vissa studier har visat att socioekonomisk status och utbildning har ett samband med risk för att drabbas av demenssjukdom. I denna studie undersöktes relationen mellan utbildning, yrkesbaserad socioekonomisk status och risk för demenssjukdom, samt ifall utfallet ser olika ut för män respektive kvinnor. Ett stickprov med 489 personer från ett longitudinellt forskningsprojekt i Umeå undersöktes varav 70 personer var drabbade av demenssjukdom. Låg yrkesbaserad socioekonomisk status visade sig mer än fördubbla risken att insjukna i en demenssjukdom jämfört med de som hade en hög yrkesbaserad socioekonomisk status. Inget signifikant samband identifierades mellan utbildningslängd och demensinsjuknande, däremot observerades en interaktionseffekt mellan kön och utbildningsnivå där kvinnor med längre utbildning verkade få ett ökat skydd mot att insjukna i demens. Resultaten går till viss del i linje med kognitiv reservteori som bland annat menar att ett högstatusyrke med mer kognitiv stimulans under livet gör individer mer motståndskraftiga mot ett demensinsjuknande. Det är även möjligt att faktorer tidigt i livet, såsom socioekonomisk status under barndomen och kognitiv förmåga, medierar associationen mellan socioekonomisk status och demens. Detta undersöktes dock inte i denna studie men skulle kunna vara av intresse att inkludera i framtida och större longitudinella studier. / The prevalence of dementia in the world is rising and is expected to reach 132 million in the year 2050. Investigating risk factors is an important part of preventive efforts. Some studies have shown that socioeconomic status and education is associated with an increased risk of dementia. This study investigated the association between education, occupational socioeconomic status and dementia. Furthermore, outcomes for men and women were investigated. A sample of 489 people from a longitudinal study in Umeå, Sweden, was examined and 70 people in the sample was afflicted by dementia. Low occupational socioeconomic status was shown to more than double the risk of being afflicted by dementia compared to those with a high occupational socioeconomic status. No significant association could be identified between the length of education and dementia but an interaction between gender and length of education was identified where more years of education had a protective effect for women. The findings are partially consistent with the cognitive reserve theory, which states that having an occupation with higher status and more cognitive stimulation during life will postpone dementia onset. It is also possible that early life circumstances like childhood socioeconomic status and cognitive ability mediates the association between socioeconomic status and dementia which makes this an interesting area of exploration for future research.

My diploma thesis is focused on the subject of biosphere reserves, as an example of special protected areas, with special regard to BR Šumava. There is examined its current situation and its contribution to sustainable development. At the same time there are being found out the opinions, attitudes and expectations of key local stakeholders and other persons and organizations concerned towards the institution BR Šumava. This thesis deals with optimal functioning model of BR Šumava and its future sustainable development.