Geospatial Sciences & Technology

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An analysis of the risk of collisions between aircraft and vultures in Namibia
(Environmental Information Service and Namibia University of Science and Technology, 2020) Hauptfleisch, Morgan; Knox, Nichola; Heita, P; Aschenborn, Ortwin; MacKenzie., Monique Lea
Collisions between aircraft and birds and other animals occur frequently and are known in the aviation industry as wildlife strikes. They are considered to be one of the most serious safety and financial risks to the global aviation industry. The International Civil Aviation Organisation, a United Nations specialised Agency, requires that the appropriate authority shall take action to eliminate or to prevent the establishment of any source which may attract wildlife to the aerodrome, or its vicinity, unless an appropriate wildlife assessment indicates that they are unlikely to create conditions conducive to a wildlife hazard problem. Namibian airports reduce the wildlife strike risk by managing the airport habitat and actively chasing birds and other hazardous animals away. The bird strike risk in airspace between airports is not managed or assessed in Namibia. Following one White-Backed Vulture strike and several reports of near-misses with vultures by pilots of small aircraft, this study investigated possible collision hotspot areas considering small commercial aircraft flight paths and vulture movement areas. The study used spatial proximity analysis and temporal overlap to compare telemetry and nesting location data for the three most commonly encountered vulture species to flight paths and times of small commercial aircraft. Collision risk hotspots were identified over three national parks: Etosha, Waterberg and the Pro-Namib portion of the Namib-Naukluft. Ascending from, or approaching, Hosea Kutako International Airport from the east was identified as a particular risk for White-backed Vulture conflict, while risk of Lappet-faced vulture strikes was high to the east of Walvis Bay airport. Flight times of vultures and aircraft corresponded greatly, increasing the collision risk. The recommendations of this work are that pilots of small commercial aircraft should be made aware of particular risk areas, and that landing at Hosea Kutako from the east, or taking off in an easterly direction should be minimised when wind conditions allow, to reduce vulture collision risk.
An analysis of the risks collisions between aircraft and vultures in Namibia
(Namibian Journal of Environment, 2020-05) Hauptfleisch, ML; Knox, Nichola; Aschenborn, O; MacKenzie, ML; Heita, P
Collisions between aircraft and birds and other animals occur frequently and are known in the aviation industry as wildlife strikes. They are considered to be one of the most serious safety and financial risks to the global aviation industry. The International Civil Aviation Organisation, a United Nations specialised Agency, requires that the appropriate authority shall take action to eliminate or to prevent the establishment of any source which may attract wildlife to the aerodrome, or its vicinity, unless an appropriate wildlife assessment indicates that they are unlikely to create conditions conducive to a wildlife hazard problem. Namibian airports reduce the wildlife strike risk by managing the airport habitat and actively chasing birds and other hazardous animals away. The bird strike risk in airspace between airports is not managed or assessed in Namibia. Following one White-Backed Vulture strike and several reports of near-misses with vultures by pilots of small aircraft, this study investigated possible collision hotspot areas considering small commercial aircraft flight paths and vulture movement areas. The study used spatial proximity analysis and temporal overlap to compare telemetry and nesting location data for the three most commonly encountered vulture species to flight paths and times of small commercial aircraft. Collision risk hotspots were identified over three national parks: Etosha, Waterberg and the Pro-Namib portion of the Namib-Naukluft. Ascending from, or approaching, Hosea Kutako International Airport from the east was identified as a particular risk for White-backed Vulture conflict, while risk of Lappet-faced vulture strikes was high to the east of Walvis Bay airport. Flight times of vultures and aircraft corresponded greatly, increasing the collision risk. The recommendations of this work are that pilots of small commercial aircraft should be made aware of particular risk areas, and that landing at Hosea Kutako from the east, or taking off in an easterly direction should be minimised when wind conditions allow, to reduce vulture collision risk.
Application of a total station in savanna vegetation surveys.
(NUST, 2004-05) Graz, F.P.
The article describes the methods used to obtain data with the use of a total station. The advantage of the proposed method is the ease with which data for investigation of spatial relationships between plants and topographical features may be obtained. In addition to location, the total station can be used to assess some plant parameters such as plant height, crown spread, trunk size and others
Application of a total station in savanna vegetation surveys.
(Namibian Scientific Society., 2004) Graz, F. P.
The article describes the methods used to obtain data with the use of a total station. The advantage of the proposed method is the ease with which data for investigation of spatial relationships between plants and topographical features may be obtained. In addition to location, the total station can be used to assess some plant parameters such as plant height, crown spread, trunk size and others.
Are urban land tenure regulations in Namibia the solution or the problem?
(Taylor & Francis, 2009) De Vries, Walter; Lewis, Joe
Land tenure in Namibia is regulated by a variety of Acts, some of which date back to as far as 1937, and some of which are yet to be approved by Cabinet. This variety of Acts makes it difficult to evaluate the performance of land administration as a whole, and the appropriateness of coercive instruments with regards to urban land tenure in particular. In this article we evaluate how urban land tenure regularization practices are conducted in Namibia, and to compare new formal procedures, designed to address problems of efficiency and efficacy, to older existing procedures, supposedly not efficient or effective. This evaluation uses a theoretical framework of (Pritchett and Woolcock, 2004) , which deals with public service delivery and transaction-intensive services. Applying this framework for a comparative analysis of 5 different land subdivision practices – each relying on a different land-related act - we conclude that the degree of regulation and regularization is perhaps not so much a solution for urban land tenure problems but perhaps more of a problem in itself.
Assessing Namibia’s performance two decades after independence.
(2011) Christiansen, T.
This paper presents the results of a study which reviews Namibia’s performance over its two decades since independence. The study examines the achievements and shortcomings of the country in various fields: politics, civil society, economy, and social / socio-economic development. The results have been split into two separate but interconnected papers. This first article analyses Namibia’s situation at the dawn of independence, its external support by foreign countries and Namibia’s overall performance as compared to the neighbouring countries Angola, Botswana, South Africa, Zambia, and Zimbabwe. The present paper evaluates in particular data drawn from the World Bank Development Indicator Database and the 2010 Ibrahim-Index of African Governance. A subsequent second paper will present a more detailed appraisal of the above-mentioned development sectors
Assessing Namibia’s performance two decades after independence. Part 2: Sectoral Analysis.
(2011) Christiansen, T.
This paper presents the results of a study which reviews Namibia’s performance over its two decades since independence. The study examines the achievements and shortcomings of the country in various fields: politics, civil society, economy, and social / socio-economic development. The results have been split into two separate but interconnected papers. This first article analyses Namibia’s situation at the dawn of independence, its external support by foreign countries and Namibia’s overall performance as compared to the neighbouring countries Angola, Botswana, South Africa, Zambia, and Zimbabwe. The present paper evaluates in particular data drawn from the World Bank Development Indicator Database and the 2010 Ibrahim-Index of African Governance. A subsequent second paper will present a more detailed appraisal of the above-mentioned development sectors.
Collaborative postgraduate programme in applied science in earth observation, Geographic Information Systems and Remote Sensing
(Klaus Hess Publishers, 2018) Louw, Frikkie; Mwewa, Lameck; Maphanyane, Joyce; Sakala, Enock; Motola, Siddique
Capacity-building in the Southern Africa Science Services Centre for Climate Change and Adaptive Land Management (SASSCAL) is an essential part of the initiative’s science programme. One of the major capacity limitations identifi ed at the Southern African Development Community (SADC) level is in the fi eld of Earth Observation, Geographic Information Systems, and Remote Sensing. Within Task 303, a collaborative Master of Science degree in Geographic Information Systems, Remote Sensing, and Earth Observation was designed and implemented by four SADC universities: University of Botswana (UB), University of Zambia (UNZA), Cape Peninsula University of Science and Technology (CPUT, SouthAfrica), and Namibia University of Science and Technology (NUST), the coordinating university.)
Comparison of Three Algorithms for the Evaluation of TanDEM-X Data for Gully Detection in Krumhuk Farm (Namibia)
(2019) Vallejo Orti, M.; Negussie, K.; Corral-Pazos-de-Provens, E.; Höfle, B.; Bubenzer, O.
Namibia is a dry and low populated country highly dependent on agriculture, with many areas experiencing land degradation accelerated by climate change. One of the most obvious and damaging manifestations of these degradation processes are gullies, which lead to great economic losses while accelerating desertification. The development of standardized methods to detect and monitor the evolution of gully-affected areas is crucial to plan prevention and remediation strategies. With the aim of developing solutions applicable at a regional or even national scale, fully automated satellite-based remote sensing methods are explored in this research. For this purpose, three different algorithms are applied to a Digital Elevation Model (DEM) generated from the TanDEM-X satellite mission to extract gullies from their geomorphological characteristics: (i) Inverted Morphological Reconstruction (IMR), (ii) Smoothing Moving Polynomial Fitting (SMPF) and (iii) Multi Profile Curvature Analysis (MPCA). These algorithms are adapted or newly developed to identify gullies at the pixel level (12 m) in our study site in the Krumhuk Farm. The results of the three methods are benchmarked with ground truth; specific scenarios are observed to better understand the performance of each method. Results show that MPCA is the most reliable method to identify gullies, achieving an overall accuracy of approximately 0.80 with values of Cohen Kappa close to 0.35. The performance of these parameters improves when detecting large gullies (>30 m width and >3 m depth) achieving Total Accuracies (TA) near to 0.90, Cohen Kappa above 0.5, and User Accuracy (UA) and Producer Accuracy (PA) over 0.50 for the gully class. Small gullies (<12 m wide and <2 m deep) are usually neglected in the classification results due to spatial resolution constraints within the input DEM. In addition, IMR generates accurate results for UA in the gully class (0.94). The MPCA method developed here is a promising tool for the identification of large gullies considering extensive study areas. Nevertheless, further development is needed to improve the accuracy of the algorithms, as well as to derive geomorphological gully parameters (e.g., perimeter and volume) instead of pixel-level classification.
The Cost of Land Registration: a Case Study of Cost Efficiency in Namibia.
(International Institute of Geo-Information Science and Earth Observation (ITC), Enschede, Netherlands, 2003-06) De Vries, W.T.; Georgiadou, P.Y (Yola).; Lewis, J.
In the light of the global discussion on reducing public and private expenditure on cadastral processes and services, this article reviews the transaction costs of land registration, based on data gathered in Namibia. The data show a large differentiation in the types of costs incurred in the process, as well as various levels of cost recovery. In addition, the degree to which delays in the operational registration processes influence the total cost to land developers and landowners is reviewed.
Description and ecology of pterocarpus angolensis in Namibia.
(NUST, 2004-05) Graz, F.P.
The tree Pterocarpus angolensis is an important component of the dry woodland savanna of northern Namibia. Its timber provides the basic resource for much of the carvings in Namibia. Unfortunately little management, particularly regeneration, has been implemented in the country and current exploitation practices amount to mining of the species.
Description and ecology of pterocarpus angolensis in Namibia.
(Namibian Scientific Society., 2004) Graz, F. P.
The tree Pterocarpus angolensis is an important component of the dry woodland savanna of northern Namibia. Its timber provides the basic resource for much of the carvings in Namibia. Unfortunately little management, particularly regeneration, has been implemented in the country and current exploitation practices amount to mining of the species.
Description and ecology of Schinziophyton rautanenii (Schinz) Radcl.-Sm. in Namibia
(NUST, 2002-02) Graz, F.P
The Manketti, Mangongo or Mangetti, Schinziophyton rautanenii (Schinz) Radcl.-Sm is an indigenous tree in Namibia, the fruit of which are of significant socio-economic value. The tree occurs in what appears to be even aged groves on deep sand, as part of the dry savanna woodlands. Natural regeneration in the woodland areas seems to be scarce, although some success has been achieved by planting truncheons.
Description and ecology of Schinziophyton rautanenii (Schinz) Radcl.-Sm. in Namibia.
(Namibian Scientific Society., 2002) Graz, F. P.
The Manketti, Mangongo or Mangetti, Schinziophyton rautanenii (Schinz) Radcl.-Sm is an indigenous tree in Namibia, the fruit of which are of significant socio-economic value. The tree occurs in what appears to be even aged groves on deep sand, as part of the dry savanna woodlands. Natural regeneration in the woodland areas seems to be scarce, although some success has been achieved by planting truncheons.
An Exploration of Participatory Mapping Approaches for Integrated Land Use Planning in the Hardap Region, Namibia.
(2013) Mundia, L.C.
The paper presents empirical findings on the potential value of participatory mapping for effective Integrated Land Use Plan (ILUP) by local communities in Hardap Region. It reflects on how future participatory approaches should be structured. The research applied a combination of approaches that include sketch mapping, photo-mapping and consultative meetings. Both positive and negative impacts of participatory mapping on ILUP were measured and local communities’ knowledge of participatory approaches objectively tested on the basis of this investigation’s findings. The research established that although participatory mapping is known to the experts in the fields of Geography, Geographical Information Systems (GIS) and Land Use Planning (LUP), it is still not well known to local land users whose knowledge of other participatory approaches that can support ILUP in Namibia is limited. Participatory maps that were produced by local communities in Hardap region suggest that local communities are willing to learn about participatory approaches and willing to share their knowledge on land use. Sketch and photo-maps - although not accurate and sometimes imprecise - were found to be satisfactory approaches to capture and document local knowledge. Local communities are motivated to improve their land use activities by the outcomes of their knowledge input in participatory mapping. Key recommendations include comprehensive participatory land use planning and better knowledge gathering from local communities. The paper presents results of participatory mapping and lessons learned from exploring participatory mapping.
An exploration of participatory mapping approaches for integrated land use planning in the Hardap Region, Namibia.
(NUST, 2013) Mundia, Lisho Christoh
The paper presents empirical findings on the potential value of participatory mapping for effective Integrated Land Use Plan (ILUP) by local communities in Hardap Region. It reflects on how future participatory approaches should be structured. The research applied a combination of approaches that include sketch mapping, photo-mapping and consultative meetings. Both positive and negative impacts of participatory mapping on ILUP were measured and local communities’ knowledge of participatory approaches objectively tested on the basis of this investigation’s findings. The research established that although participatory mapping is known to the experts in the fields of Geography, Geographical Information Systems (GIS) and Land Use Planning (LUP), it is still not well known to local land users whose knowledge of other participatory approaches that can support ILUP in Namibia is limited. Participatory maps that were produced by local communities in Hardap region suggest that local communities are willing to learn about participatory approaches and willing to share their knowledge on land use. Sketch and photo-maps - although not accurate and sometimes imprecise - were found to be satisfactory approaches to capture and document local knowledge. Local communities are motivated to improve their land use activities by the outcomes of their knowledge input in participatory mapping. Key recommendations include comprehensive participatory land use planning and better knowledge gathering from local communities. The paper presents results of participatory mapping and lessons learned from exploring participatory mapping.
Fire damage to Schinziophyton rautanenii (Schinz) trees in north-eastern Namibia.
(NUST, 2003-05) Graz, F.P.
The nuts of the Mangetti, Schinziophyton rautanenii, are an important food source for a number of rural communities. The environment in which the tree grows, however, is subject to frequent burning. A number of trees have been seen with a characteristic inverted U-shaped fire lesion on the base of the trunk. A collapsed trunk as well as a vertical scar in the same tree showed that heavy branches or a second trunk may collapse under their own weight, thus providing a point for fire entry.
Fire damage to Schinziophyton rautanenii (Schinz) trees in north-eastern Namibia.
(Namibian Scientific Society., 2003) Graz, F. P.
The nuts of the Mangetti, Schinziophyton rautanenii, are an important food source for a number of rural communities. The environment in which the tree grows, however, is subject to frequent burning. A number of trees have been seen with a characteristic inverted U-shaped fire lesion on the base of the trunk. A collapsed trunk as well as a vertical scar in the same tree showed that heavy branches or a second trunk may collapse under their own weight, thus providing a point for fire entry.
Law Reform for Improved Delivery of Land to the Urban Poor
(Ministry of Justice Law Reform and Development Commission, 2017) Zongwe, D.P.; Dausab, Y.
The current formal land tenure system in Namibia is unable to effectively deal with the huge backlog in formalization of informal settlements, most of which are in the rural areas of Namibia. The system is considered too slow and expensive for this purpose, and is also perceived as only benefiting the rich, while being inaccessible and too expensive for the poor. The proposed Flexible Land Tenure System (FLTS) aims to resolve this problem by implementing cheaper forms of land tenure, and bringing cadastral services closer to the poor. The system offers security of title, but the titles have significant limitations compared to freehold. It is questionable whether the FLTS will significantly accelerate the delivery of land to the poor, and whether it will indeed achieve the aims of a pro-poor land tenure system. It might in fact burden the poor with an inferior land tenure system, thereby becoming an obstacle rather than an instrument for poverty reduction and economic development. The formal land tenure system, on the other hand, is in urgent need of reform. The development of the new Urban and Regional Planning Bill, Deeds Registries Act, Flexible Land Tenure Regulations, and the current review of land survey related regulations, present an opportunity to address this issue. The development of these acts and regulations should be approached in a holistic manner aimed at improving land delivery and administration in general, with specific focus on the needs of the urban poor. The aim should be to make the system accessible and beneficial to all classes of society, thereby eliminating the need for a parallel system for the poor.
Mapping and Monitoring Fractional Woody Vegetation Cover in the Arid Savannas of Namibia Using LiDAR Training Data, Machine Learning, and ALOS PALSAR Data
(2019-11) Knox, Nichola; Wessels, Konrad; Mathieu, Renaud; Main, Russell; Naidoo, Laven; Steenkamp, Karen
Namibia is a very arid country, which has experienced significant bush encroachment and associated decreased livestock productivity. Therefore, it is essential to monitor bush encroachment and widespread debushing activities, including selective bush thinning and complete bush clearing. The aim of study was to develop a system to map and monitor fractional woody cover (FWC) at national scales (50 m and 75 m resolution) using Synthetic Aperture Radar (SAR) satellite data (Advanced Land Observing Satellite (ALOS) Phased Arrayed L-band Synthetic Aperture Radar (PALSAR) global mosaics, 2009, 2010, 2015, 2016) and ancillary variables (mean annual precipitation—MAP, elevation), with machine learning models that were trained with diverse airborne Light Detection and Ranging (LiDAR) data sets (244,032 ha, 2008–2014). When only the SAR variables were used, an average R2 of 0.65 (RSME = 0.16) was attained. Adding either elevation or MAP, or both ancillary variables, increased the mean R2 to 0.75 (RSME = 0.13), and 0.79 (RSME = 0.12). The inclusion of MAP addressed the overestimation of FWC in very arid areas, but resulted in anomalies in the form of sharp gradients in FWC along a MAP contour which were most likely caused by to the geographic distribution of the LiDAR training data. Additional targeted LiDAR acquisitions could address this issue. This was the first attempt to produce SAR-derived FWC maps for Namibia and the maps contain substantially more detailed spatial information on woody vegetation structure than existing national maps. During the seven-year study period the Shrubland–Woodland Mosaic was the only vegetation structural class that exhibited a regional net gain in FWC of more than 0.2 across 9% (11,906 km2) of its area that may potentially be attributed to bush encroachment. FWC change maps provided regional insights and detailed local patterns related to debushing and regrowth that can inform national rangeland policies and debushing programs.

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