This research evaluated the extent to which forests in Virginia have either become fragmented (disconnected) and/or connected over a ten year time period. The study analyzed the accuracy of forest fragmentation analysis depending on the spatial resolution of the satellite imagery used. This analysis highlights the importance of using appropriate satellite images for forest fragmentation analysis. Secondly, this research focused on building a model to identify the significance of factors such as slope, physiographic region and forest types on Virginia's populations of Wood Thrush and Ovenbird. This assessment identified the difference in effects of variables on bird populations depending on the scale at which the analysis is carried out. Third and final analysis combined the first two assessments to determine how management policies can be used to mitigate negative effects of forest fragmentation and protect biodiversity. The research results highlight increasing forest fragmentation trends in Virginia between 2001 and 2011 and the negative impacts of this trend on Wood Thrush and Ovenbird species. The results also demonstrate the effectiveness of riparian buffers as corridors. / Doctor of Philosophy / This research evaluated the extent to which forests in Virginia have either become fragmented (disconnected) and/or connected over a ten year time period. The study analyzed the accuracy of forest fragmentation analysis depending on the spatial resolution of the satellite imagery used. This analysis highlights the importance of using appropriate satellite images for forest fragmentation analysis. Secondly, this research focused on building a model to identify the significance of factors such as slope, physiographic region and forest types on Virginia’s populations of Wood Thrush and Ovenbird. This assessment identified the difference in effects of variables on bird populations depending on the scale at which the analysis is carried out. Third and final analysis combined the first two assessments to determine how management policies can be used to mitigate negative effects of forest fragmentation and protect biodiversity. The research results highlight increasing forest fragmentation trends in Virginia between 2001 and 2011 and the negative impacts of this trend on Wood Thrush and Ovenbird species. The results also demonstrate the effectiveness of riparian buffers as corridors.

Darbo tikslas: atlikti Neries upės ichtiofaunos rūšinės sudėties, gausumo ir pasiskirstymo analizę pagal turimas ataskaitas bei literatūros šaltinius. Darbo objektas: Neries upė. Darbo metodai: darbas atliktas panaudojant literatūroje skelbtas pagal temą metodikas bei atlikta turimų duomenų analizė. Kadangi ichtiofaunos (nektono) rūšinė sudėtis esminiai skiriasi ne tik sistematiniu požiūriu, bet ir fiziniais parametrais jie buvo tiriami pagal sekančias metodikas skirtas Neries upės ichtiofaunai. Detaliau buvo analizuojama vykstantys pokyčiai tarp atskirų hidrobiontų grupių. Darbo rezultatai: Upės nektoną dažniausiai sudaro žuvys. Jų įvairovė gana didelė. Dalis organizmų gyvena priekrantėse, kiti laikosi prie dugnų, dar kitos – vandens sluoksnyje. Neries upės nektoną sudaro lašišos, upėtakiai, šlakiai, salačiai ir kt. žuvys. Upių žuvingumą lemia natūralūs ir antropogeniniai veiksniai. Neries hidrobiontus labiausiai įtakoja vandens tarša, kuri yra ir organinė ir cheminė. / The aim of the thesis: to perform analysis of ichthyofauna of Neris river on the basis of existing sources of literature and scientific reports of the Institute of Ecology. The object of the thesis: Neris river. The work methods: the methods published in the literature, corresponding to the topic of the thesis, were applied in the work, and analysis of the existing data was performed. As species composition of ichthyofauna (nekton) differs essentially not only in the systematic respect, but also by physical parameters, they were investigated with application of the following parameters intended for ichthyofauna of Neris river. The changes occurring between different groups of hydrobionts were analysed in more detail. The results of the thesis: Nekton of the river consists mainly of fish. Their variety is rather large. Some organisms live in the littoral area, some at the bottom, others in the water layer. Nekton of Neris river consists of salmon, trout, sea trout, asp, etc.. Quantity of fish is determined by natural and anthropogenic factors. The hydrobionts of Neris river are mainly influenced by water pollution, both organic and chemical.

Conducting species inventories is important to provide baseline information essential for management and conservation. Furthermore, understanding the effects of anthropogenic and environmental factors on species richness and occurrence are crucial to conserve species. Aldesa Valley lies in the Tabuk Region of Saudi Arabia, and because of the presence of permanent water and vegetation, is thought to contain high biodiversity. I estimated avian species richness and occurrence in Aldesa Valley during May 10–August 10 in 2014 and 2015 to detect bird species richness and occurrence. I used generalized linear models and occupancy models for six commonly detected bird species. I recorded 24 bird species, and found that species richness and occupancy was affected by numerous anthropogenic and environmental factors that influenced species detection and presence. I encourage more biological inventories to further document species occurrences and facilitate conservation of the unique species assemblages in Aldesa Valley.

Development on dolomite poses a risk due to the possible formation of instability features such as sinkholes. Most of these features are however man-induced, and the risk associated with development on dolomitic areas can be mitigated through correct management. Therefore, since the Tlokwe City Council is accountable for safe development within its jurisdiction, a Dolomite Risk Management Strategy (DRMS) should be put in place. There are several factors that contribute to the risk for development on dolomite. These factors can be catagorised into two groups that should be considered during the hazard identification process, namely physical factors that consists of geology, geohydrology and geotechnical, and anthropogenic factors that consists of existing infrastructure and development, land use planning, as well as social structure and awareness. These factors are assessed by means of a risk assessment in order to obtain a disaster risk score for different areas within the study area. Based on this score, priority focus areas can be identified, mainly for critically important further research before any development can be allowed or mitigation measures implemented. Once these research activities are completed, a DRMS can be compiled based on the guidelines set by SANS 1936, which will promote the safety of people and property when further development on dolomite takes place. Urgent and interim mitigation measures are proposed to manage the risk during further research activities. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

Development on dolomite poses a risk due to the possible formation of instability features such as sinkholes. Most of these features are however man-induced, and the risk associated with development on dolomitic areas can be mitigated through correct management. Therefore, since the Tlokwe City Council is accountable for safe development within its jurisdiction, a Dolomite Risk Management Strategy (DRMS) should be put in place. There are several factors that contribute to the risk for development on dolomite. These factors can be catagorised into two groups that should be considered during the hazard identification process, namely physical factors that consists of geology, geohydrology and geotechnical, and anthropogenic factors that consists of existing infrastructure and development, land use planning, as well as social structure and awareness. These factors are assessed by means of a risk assessment in order to obtain a disaster risk score for different areas within the study area. Based on this score, priority focus areas can be identified, mainly for critically important further research before any development can be allowed or mitigation measures implemented. Once these research activities are completed, a DRMS can be compiled based on the guidelines set by SANS 1936, which will promote the safety of people and property when further development on dolomite takes place. Urgent and interim mitigation measures are proposed to manage the risk during further research activities. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

Dans l'Arctique, le risque de transmission de maladies zoonotiques comme la rage est encore une préoccupation pour la santé publique, avec plusieurs cas rapportés chaque année chez différentes espèces animales. L’interface entre la faune sauvage, les animaux domestiques et les humains pour la transmission de maladies sera en augmentation en raison des pressions grandissantes du développement anthropique et du réchauffement climatique. Les interactions directes entre les chiens domestiques des villages nordiques et les renards sauvages, les principales sources d’exposition à la rage, sont des évènements critiques pour l’exposition des humains au virus, mais très peu d’études se sont attardées à ce sujet. Les objectifs de ce projet sont 1- de décrire et de quantifier l’activité spatiale et temporelle des renards et des chiens libres et d’identifier les facteurs anthropiques et environnementaux qui influencent leur présence à proximité et dans les villages nordiques, 2- de quantifier les contacts directs et le potentiel d’interactions entre les renards et les chiens libres afin de mieux identifier les périodes et les zones avec un risque de transmission de la rage, 3- de comparer et discuter des résultats de l’activité des renards et des chiens libres et leur potentiel d’interactions entre les deux villages nordiques à l’étude et 4- d’identifier des méthodes de gestion pour diminuer les opportunités d’interactions entre les renards et les chiens libres. Afin de détecter la présence des deux carnivores, un réseau de caméras automatiques a été installé sur une grille spatiale autour et à l’intérieur de deux villages typiques du Nord, Kuujjuaq (près de la limite des arbres) et Inukjuak (à > 100 km de la limite des arbres). Pour chaque station caméra, différents facteurs anthropiques et environnementaux ont été évalués (distance au dépotoir, distance à l’aéroport, densité d’habitations, densité de chiens de traîneau, distance aux rues, distance à l’eau, indice de végétation). Les contacts directs et les indices d’interaction ont été calculés pour évaluer le potentiel d’interactions entre les renards et les chiens libres. Les opportunités d’interactions entre les renards et les chiens sont plus élevées à l’aube et au crépuscule pendant les mois d'octobre et de novembre en périphérie des deux villages, particulièrement près des chiens de traîneau et légèrement près du dépotoir municipal (KU) et de l’aéroport (IN). Les renards roux et les renards arctiques ont été observés à proximité et dans les deux villages, mais les renards roux sont plus souvent observés à Kuujjuaq (87% des observations) qu’à Inukjuak (renards arctiques : 74% des observations), ce qui reflète également des particularités biotiques et abiotiques uniques à chaque village. Les résultats suggèrent que les opportunités d’interactions entre les renards et les chiens représentent un risque d’exposition à la rage pour les chiens et les humains, et possiblement pour d’autres pathogènes nordiques transmissibles entre les chiens et la faune. Cependant, les évènements de contacts directs interspécifiques renard-chien sont rares et les opportunités d’interactions sont concentrées dans le temps et dans des zones restreintes, ce qui peut aider à cibler des mesures préventives visant à limiter les évènements de transmission. Cette étude fournit la première documentation sur l'activité des renards et leurs interactions avec les chiens libres dans les villages de l'Arctique. L’application d’une approche « Une seule Santé » devrait être utilisée pour prévenir ou diminuer le risque de transmission de la rage entre les renards et les chiens. / In the Arctic, the risk of transmission of zoonotic diseases like rabies is still a public health concern, with several cases reported each year in different animal species. The interface between wildlife, domestic animals and humans for disease transmission will be increasing due to pressures from anthropogenic development and global warming. Direct interactions between domestic dogs in northern communities and wild foxes, the main source of rabies exposure, are critical of human exposure to the virus, but very few studies have focused on this. The objectives of this project are 1- to describe and quantify the spatial and temporal activity of free-ranging dogs and foxes, and identify the anthropogenic and environmental factors that influence their presence near and within northern villages, 2- to quantify direct contacts and the potential for interactions between free-ranging dogs and foxes in order to better identify periods and areas of higher risk of rabies transmission, 3- to compare and contrast dog-fox activity and interactions between the two northern villages under study, and 4- to identify management methods to reduce opportunities for fox-dog interactions. To detect the presence of the two carnivores, we set up a network of automatic cameras near and within two typical northern villages, i.e., Kuujjuaq (near the tree line) and Inukjuak (> 100 km from the tree line). For each camera, different anthropogenic and environmental factors were evaluated (distance to the landfill, distance to the airport, density of dwellings, density of sled dogs, distance to streets, distance to water, vegetation index). Direct contacts and interaction index were calculated to assess the potential for interactions between foxes and free-roaming dogs. Interaction opportunities between foxes and dogs are more likely to occur at dawn and dusk during the months of October and November, and on the outskirts of both villages, particularly near sled dogs and slightly nearer to the landfill (KU) and the airport (IN). Red and Arctic foxes were observed in and around both villages, but red foxes were more frequently observed in Kuujjuaq (87% of observations) while Arctic foxes were more frequent in Inukjuak (74% of observations), which also reflects the biotic and abiotic particularities specific to each village. These results suggest that fox-dog contacts around and within the village are likely, posing a real risk of peri-domestic rabies transmission to dogs and humans, and possibly for other northern pathogens transmissible between wildlife and dogs. Nevertheless, interspecific direct contact events are rare and interaction opportunities are concentrated in time and space, which may help target preventive measures aimed at limiting transmission events. This study provides the first documentation on the activity of foxes and their interactions with dogs and humans in Arctic communities. Considering the potential risk-by-proximity described in our study, a “One Health” approach could be applied to prevent or lower fox-dog rabies transmission.

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

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