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Birds of the riparian corridors of Potchefstroom, South Africa / Rindert WymaWyma, Rindert January 2012 (has links)
A riparian ecosystem is the area between the aquatic and terrestrial setting of a stream, and serves as a corridor and habitat for birds. Several riparian ecosystems are located in urban environments, and three main riparian corridors are located in Potchefstroom. They are the Mooi River, Wasgoed Spruit, and Spitskop Spruit, which encompass a wide range of different vegetation types and anthropogenic factors. Therefore, different habitat types for birds occur along the riparian corridors of Potchefstroom. Factors such as food and water availability, nesting sites, competition, predation, learning, presence of other species, and those species that are able to adapt to environmental changes influence the avian diversity and communities along riparian corridors.
The hypothesis is that bird variables along the riparian corridors in Potchefstroom are affected by vegetation, anthropogenic, and seasonal influences. To investigate these affects, two secondary objectives were formulated. The first was to characterise riparian avian habitats (CAHs) according to vegetation and anthropogenic factors, and the second was to identify temporal and spatial changes in avian variables.
The three streams were divided into 79 consecutive transects, each 300 m long. The study area consisted of: 17 transects along Spitskop Spruit, 12 along Wasgoed Spruit and 50 along the Mooi River. Bird observations were conducted monthly from June 2006 to June 2007. Birds that were observed with a perpendicular distance ≤ 30 meters towards the streams were included in the results. The bird species that were observed were also classified into different nesting and feeding guilds.
Environmental data recorded included: vegetation structure (estimated cover percentages and height classes of trees, shrubs, grasses, herbs, sedges, and reeds), anthropogenic structures (estimated cover percentages of roads, footpaths, bridges, electrical pylons, houses, and drainage pipes), and the presence of informal settlers along each transect (the mean number of people and the space they occupy). Vegetation was monitored in summer– (February 2007 until April 2007) and winter months (June 2007 until August 2007). The anthropogenic structures and the presence of informal settlers (anthropogenic factors) were monitored simultaneously with the bird counts.
Transect-time profiles were drawn for the four parameters, which differed on spatial and time scales. Multivariate analyses included non-metric multidimensional scaling (NMS), cluster analysis, and indicator species analysis. Cluster analyses and NMS bi-plots were used to define characterised avian habitats (CAHs). Two types of CAHs were characterised: Summer CAHs (summer vegetation and anthropogenic factors) and Anthropogenically CAHs (Anthropogenic factors alone). Bird species were then ordinated with the summer and anthropogenically CAHs on NMS successional vector graphs. The successional vectors illustrate the avian community trajectories of the different CAHs. Indicator species analyses were performed to describe associations between the bird species and the summer and anthropogenically CAHs.
The summer and anthropogenic CAHs that were characterised had different avian community trajectories and different species were associated with these CAHs. Different levels in avian diversity appeared among these CAHs, and convergence and divergence in communities appeared among these CAHs. Birds also selected their habitats according to feeding and nesting behaviours.
Consequently, it can be deduced that environmental factors such as vegetation structures and anthropogenic factors, as well as seasonality, had an effect on the distribution of birds along the riparian corridors of Potchefstroom. / Thesis (Master of Environmental Sciences)--North-West University, Potchefstroom Campus, 2013
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Birds of the riparian corridors of Potchefstroom, South Africa / Rindert WymaWyma, Rindert January 2012 (has links)
A riparian ecosystem is the area between the aquatic and terrestrial setting of a stream, and serves as a corridor and habitat for birds. Several riparian ecosystems are located in urban environments, and three main riparian corridors are located in Potchefstroom. They are the Mooi River, Wasgoed Spruit, and Spitskop Spruit, which encompass a wide range of different vegetation types and anthropogenic factors. Therefore, different habitat types for birds occur along the riparian corridors of Potchefstroom. Factors such as food and water availability, nesting sites, competition, predation, learning, presence of other species, and those species that are able to adapt to environmental changes influence the avian diversity and communities along riparian corridors.
The hypothesis is that bird variables along the riparian corridors in Potchefstroom are affected by vegetation, anthropogenic, and seasonal influences. To investigate these affects, two secondary objectives were formulated. The first was to characterise riparian avian habitats (CAHs) according to vegetation and anthropogenic factors, and the second was to identify temporal and spatial changes in avian variables.
The three streams were divided into 79 consecutive transects, each 300 m long. The study area consisted of: 17 transects along Spitskop Spruit, 12 along Wasgoed Spruit and 50 along the Mooi River. Bird observations were conducted monthly from June 2006 to June 2007. Birds that were observed with a perpendicular distance ≤ 30 meters towards the streams were included in the results. The bird species that were observed were also classified into different nesting and feeding guilds.
Environmental data recorded included: vegetation structure (estimated cover percentages and height classes of trees, shrubs, grasses, herbs, sedges, and reeds), anthropogenic structures (estimated cover percentages of roads, footpaths, bridges, electrical pylons, houses, and drainage pipes), and the presence of informal settlers along each transect (the mean number of people and the space they occupy). Vegetation was monitored in summer– (February 2007 until April 2007) and winter months (June 2007 until August 2007). The anthropogenic structures and the presence of informal settlers (anthropogenic factors) were monitored simultaneously with the bird counts.
Transect-time profiles were drawn for the four parameters, which differed on spatial and time scales. Multivariate analyses included non-metric multidimensional scaling (NMS), cluster analysis, and indicator species analysis. Cluster analyses and NMS bi-plots were used to define characterised avian habitats (CAHs). Two types of CAHs were characterised: Summer CAHs (summer vegetation and anthropogenic factors) and Anthropogenically CAHs (Anthropogenic factors alone). Bird species were then ordinated with the summer and anthropogenically CAHs on NMS successional vector graphs. The successional vectors illustrate the avian community trajectories of the different CAHs. Indicator species analyses were performed to describe associations between the bird species and the summer and anthropogenically CAHs.
The summer and anthropogenic CAHs that were characterised had different avian community trajectories and different species were associated with these CAHs. Different levels in avian diversity appeared among these CAHs, and convergence and divergence in communities appeared among these CAHs. Birds also selected their habitats according to feeding and nesting behaviours.
Consequently, it can be deduced that environmental factors such as vegetation structures and anthropogenic factors, as well as seasonality, had an effect on the distribution of birds along the riparian corridors of Potchefstroom. / Thesis (Master of Environmental Sciences)--North-West University, Potchefstroom Campus, 2013
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Die invloed van 'n motories fundamentele vaardigheidsprogram op die fisieke en kognitiewe ontwikkeling van die graad 1 kind (Afrikaans)Kruger, Elmien 24 November 2003 (has links)
The primary aim of this study was to evaluate the influence of an eight-week fundamental motor skills program on the physical and cognitive development of Grade 1 learners. The Basic Motor Ability Test was used in the evaluation of the 39 learners that formed the experimental group as well as for the 29 learners in the control group. Two additional subtests were included, namely the 400m endurance run and a dynamic balance test. After the initial testing the experimental group participated in an eight-week skills program for 30 minutes a day, four days a week. The program included stability, locomotor and manipulation activities. Hereafter a retest was done. The control group only completes the test and retest and not the skills program. The data of the variables tested were coded in computer format and statistically evaluated. In the processing of the data, the raw datum (performance) was converted to percentile norms. In order to determine if a child had improved in a certain physiological parameter percentile norms are used. The t-test was used to determine if the skills program had a positive influence on the variables tested. Two different t-test were used: the t-test for independent groups and the t-test for paired groups. The experimental research revealed that the skills program did not have a significant influence on most of the tested variables. In some instances the experimental and control groups were not on the same level at the start of the research, which made it more difficult to compare the two groups. For some variables both the experimental and control groups improved which is an indication that the improvement cannot be ascribed to the skills program alone. The following two variables, sit-and-reach and co-ordination (hand-eye) did improve notably and it may be due to the influence of the skills program. In both instances the average performance of the experimental group improved while this improvement was not evident in the control group. The cognitive variables were assessed by a questionnaire administered by each learner’s teacher after the conclusion of the skills program. Only the experimental group was involved. The questionnaire consisted of six questions comprising both categorical and open responses. The cognitive variables that were assessed were the following: 1. venturesome ness; 2. attention and concentration; 3. self esteem; 4. socialization and ability to work in a group; 5. ability to plan; and 6. ability to finish his/her given task. The results indicated that more than half of the learners improved in all the cognitive variables. Socialization and the ability to work in a group improved in most of the learners. / Thesis (DPhil (Human Movement Science))--University of Pretoria, 2005. / Biokinetics, Sport and Leisure Sciences / unrestricted
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