The exponential growth of the human population is limiting the wildlife habitat all around the word. In recent years habitat loss and fragmentation is one of the main reasons that threats the wild life species. The Grévy’s zebra (Equus grevyi) is the most endangered member of Zebras. Their historical range was previously from north Ethiopia to southwest Somalia and to northern Kenya. Currently they are distributed only in fragmented habitats in central and eastern part of Ethiopia and in the north of Kenya. They are listed as endangered in the IUCN red list, as their population has declined 68% in 27 years. There are very few studies on genetic structure of this species, and investigating the genetic connection between different populations is needed. Molecular markers are one of the best tools to understand the level of fragmentation, population bottlenecks or potential inbreeding. In this study, the population structure of Ethiopian zebra population from Alledeghi Wildlife Reserve (WR) and Sarite area was studied using non-invasively obtained fecal samples collected during 2001-2011. This study analyzes genetic variation at 10 microsatellite loci and a 350-bp fragment of the mitochondrial DNA control region. The results showed that the genetic diversity is very low between the populations (π=0.00116 for Alledeghi WR and π=0 for Sarite population). The population of Alledeghi WR is probably isolated from the population of Sarite, as they don’t share any haplotypes. As the population of Alledeghi WR is separated from the ones from Sarite and Kenya, applying more conservational programs in this area is needed to protect the genetic diversity of the Grévy’s zebras in this area.

Pattern of Linkage Disequilibrium (LD) is a major factor largely determining the power of association mapping studies. Along with nucleotide diversities and DNA polymorphism, knowledge of patterns of LD along the genome needs to be to known to effectively design association mapping studies. In this study, patterns of nucleotide diversity, population structure, LD was estimated in Norway spruce (Picea abies). The data used for this were 23 nuclear loci sequenced in around 90 individuals originating from natural populations of Norway spruce throughout the current distribution range in Sweden and Finland. The observed levels of nucleotide diversity are variable among loci varying between 0.002 and 0.008 if measured by average pairwise nucleotide diversity. Despite the samples stretching large part of Finland and Sweden there were no evidence for strong population structure. As in earlier studies LD decays fast with distance and the average pattern of the squared correlation of allele frequencies drops to less than 0.2 within 100bp. In order to put the data in perspective previously generated data sets were re-analyzed and compared to the inferred results.

Revegetation is employed to mitigate the spread of mine tailings in the environment by ameliorating tailings with organics to promote plant cover. Revegetation has proven to be successful in establishing plant cover, but the long-term effects are largely unknown. A field study was conducted to evaluate the success of four artificially revegetated tailings from Manitoba by comparing plant cover and diversity. Central Manitoba, Flin Flon, and Thompson had moderate cover while cover was low in Lynn Lake. All four sites had low diversity and were composed of early-successional species. The results suggest that while current revegetation methods promote plant growth on tailings, it is currently difficult to determine if and how the vegetation will progress from a grass-legume community to a boreal forest. In addition, while various amounts of effort were invested into each site, the results indicate the degree of remediation does not affect overall success.

Amphibians are of great ecological importance and a loss of species will have widespread and dire consequences. Recent population declines and extinctions have resulted in amphibians being labelled the most threatened vertebrate class on a global scale. The unique Okavango ecosystem is well known and documented, yet the amphibians of this region are poorly known. This project aimed at assessing diversity in the Okavango Delta by testing isolation as a possible driver for community composition; determining the effect of hydrology on breeding behaviour; and assessing the status and prevalence of the pathogen Batrachochytrium dendrobatidis (Bd) responsible for the widespread epidemic chytridiomycosis implicated in amphibian decline. Using various monitoring techniques, observations of species occurrence were made at three locations representing different degrees of isolation over a 20 month period. Breeding indicators were observed and frogs were screened for amphibian chytrid fungus. A total of 29 species were recorded, and results indicated that there were no significant differences in community composition between the sampled localities. Species presence, however, was significantly correlated with habitat type. Thus, the availability of suitable habitat appears to be driving amphibian diversity patterns, rather than geographic isolation; and increased habitat diversity near the Delta periphery explains increased amphibian diversity in these areas. Results from breeding indicators suggested that reproduction in continuous breeders was correlated with the annual flood as well as rainfall, whilst that of explosive breeders was correlated with rainfall alone. It is thus proposed that opportunistic breeding behaviour for some amphibian species is driven by the hydrology of the ecosystem; and this may be explained by increased biological production associated with the flood pulse. Outcomes highlight the unique nature of the Okavango Delta system, and emphasises the need for its preservation. A total of 249 swab samples were collected and screened for amphibian chytrid fungus. The geographical distribution of collection samples were evenly spread throughout the localities, and were obtained from at least 25 amphibian species. Analyses proved negative for Bd for the 79.92% swabs analysed thus far and it is concluded that Bd seems absent in the study region, a result which has massive conservation implications for the region. Despite the fact that the Okavango Delta has benefitted from conservation and tourism efforts in the past, the system and its biodiversity remains threatened and effective conservation management strategies must be devised and implemented to ensure its preservation. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

Amphibians are of great ecological importance and a loss of species will have widespread and dire consequences. Recent population declines and extinctions have resulted in amphibians being labelled the most threatened vertebrate class on a global scale. The unique Okavango ecosystem is well known and documented, yet the amphibians of this region are poorly known. This project aimed at assessing diversity in the Okavango Delta by testing isolation as a possible driver for community composition; determining the effect of hydrology on breeding behaviour; and assessing the status and prevalence of the pathogen Batrachochytrium dendrobatidis (Bd) responsible for the widespread epidemic chytridiomycosis implicated in amphibian decline. Using various monitoring techniques, observations of species occurrence were made at three locations representing different degrees of isolation over a 20 month period. Breeding indicators were observed and frogs were screened for amphibian chytrid fungus. A total of 29 species were recorded, and results indicated that there were no significant differences in community composition between the sampled localities. Species presence, however, was significantly correlated with habitat type. Thus, the availability of suitable habitat appears to be driving amphibian diversity patterns, rather than geographic isolation; and increased habitat diversity near the Delta periphery explains increased amphibian diversity in these areas. Results from breeding indicators suggested that reproduction in continuous breeders was correlated with the annual flood as well as rainfall, whilst that of explosive breeders was correlated with rainfall alone. It is thus proposed that opportunistic breeding behaviour for some amphibian species is driven by the hydrology of the ecosystem; and this may be explained by increased biological production associated with the flood pulse. Outcomes highlight the unique nature of the Okavango Delta system, and emphasises the need for its preservation. A total of 249 swab samples were collected and screened for amphibian chytrid fungus. The geographical distribution of collection samples were evenly spread throughout the localities, and were obtained from at least 25 amphibian species. Analyses proved negative for Bd for the 79.92% swabs analysed thus far and it is concluded that Bd seems absent in the study region, a result which has massive conservation implications for the region. Despite the fact that the Okavango Delta has benefitted from conservation and tourism efforts in the past, the system and its biodiversity remains threatened and effective conservation management strategies must be devised and implemented to ensure its preservation. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

<p>My dissertation identifies and deconstructs the interracial codes of conduct produced and enacted by three distinct racial-ethnic communities in an integrated neighborhood. My analysis of Creekridge Park is based on data collected via in-depth interviews, a neighborhood survey, and participant observation. By addressing the particularities of an integrated neighborhood, this project augments traditional index-based studies of segregation research and examines how the concept of social distance can explain the quantity and quality of encounters between Black, White, and Latino/a residents. I also evaluate the social environment of an integrated neighborhood by documenting and questioning the attitudes, behaviors, and relationships of neighborhood residents. Finally, I analyze the data using modified grounded theory, an iterative process that uses data and existing theory to develop conceptual models. Overall, this project emphasizes the importance of race as a social marker of status, privilege, and marginalization; the limits of diversity as an emancipating ideology; and the importance of power as a conceptual tool in analyses of White and nonwhite experiences in integrated settings.</p> / Dissertation

No description available.

Revegetation is employed to mitigate the spread of mine tailings in the environment by ameliorating tailings with organics to promote plant cover. Revegetation has proven to be successful in establishing plant cover, but the long-term effects are largely unknown. A field study was conducted to evaluate the success of four artificially revegetated tailings from Manitoba by comparing plant cover and diversity. Central Manitoba, Flin Flon, and Thompson had moderate cover while cover was low in Lynn Lake. All four sites had low diversity and were composed of early-successional species. The results suggest that while current revegetation methods promote plant growth on tailings, it is currently difficult to determine if and how the vegetation will progress from a grass-legume community to a boreal forest. In addition, while various amounts of effort were invested into each site, the results indicate the degree of remediation does not affect overall success.

Orthogonal Frequency Division Multiplexing, so called OFDM, has found a prominent place in various wireless systems and networks as a method of encoding data over multiple carrier frequencies. OFDM-based communication systems, however, lacking inherent diversity, are capable of benefiting from different spatial diversity schemes. One such scheme, Cyclic Delay Diversity (CDD) is a method to provide spatial diversity which can be also interpreted as a Space-Time Block Coding (STBC) step. The main idea is to add more transmit antennas at the transmitter side sending the same streams of data, though with differing time delays. In [1], the capacity of a point-to-point OFDM-based channel with CDD is derived for inputs with Gaussian and discrete constellations. In this dissertation, we use the same approach for an OFDM-based single-input single-output (SISO) two-user interference channel (IC). In our model, at the receiver side, the interference is treated as noise. Moreover, since the channel is time-varying (slow-fading), the Shannon capacity in the strict sense is not well-defined, so the expected value of the instantaneous capacity is calculated instead. Furthermore, the channel coefficients are unknown to the transmitters. Thus, in this setting, the probability of outage emerges as a reasonable performance measure. Adding an extra antenna in the transmitters, the SISO IC turns into an MISO IC, which results in increasing the diversity. Both the continuous and discrete inputs are studied and it turns out that decoding interference is helpful in some cases. The results of the simulations for discrete inputs indicate that there are improvements in terms of outage capacity compared to the ICs with single-antenna transmitters.

The roles of urban public spaces in urban cores are being re-assessed across many North American cities. Public spaces within downtown cores are essential in ensuring the long- term viability of such urban centers economically and socially. Public spaces have been researched by utilizing a number of theories and frameworks in the past few decades, most notably through a socio-cultural lens. Another possible method of assessing what makes a great public space in a downtown core is by looking at how diverse a range of activities and uses it provides. The City of Vancouver’s downtown core has undergone massive redevelopment schemes in the past two decades. The downtown area has been transformed into a hub that not only retains major commercial and retail functions in the City but also boasting an active and increasing residential population living in mixed-use high density condominiums. Downtown Vancouver’s public spaces have also been increasing in number during the past two decades, on par with promoting a more active outdoor lifestyle for both residents and visitors. Assessing the degree to which the range of uses and activities meet the diverse range of users’ expectations and requirements is a possible method of analyzing these spaces’ viability in the public realm. Data for this research was collected by reviewing previous literature, unobtrusive observation and mapping of activities, compiling contextual maps of surrounding areas and usage maps for each selected public space, administering on-site user surveys, and conducting semi-structured interviews with professional and academic actors involved with planning, maintaining, and designing public spaces. Through conducting this research, it was found out that while some public spaces in Downtown Vancouver are more successful in terms of being used in a variety of ways, others are less so. Downtown Vancouver was also found to be lacking central public spaces such as plazas and squares, as these spaces would provide for a wider range of activities in the public realm. A number of strategies need to be taken by planners, officials in the City, and other actors in order to ensure more diverse range of activities in Downtown Vancouver’s public spaces in the future.