11 research outputs found
Remote sensing-based fire frequency mapping in a savannah rangeland
Burnt area mapping and fire frequency analysis were carried out in Hwange National Park, Zimbabwe. Hwange National Park typifies a savannah ecosystem which is semi-arid and fire-prone. This paper presents a geospatial analysis to quantify the spatial distribution and fire frequency from 2000 to 2006. Moderate Resolution Imaging Spectroradiometer (MODIS) images from 2000 to 2006 were obtained and classified for burnt area mapping. Linear pixel unmixing was used for image classification and subsequent mapping of burnt areas. The results showed that it was feasible to have discrimination of burnt areas and ‘un-burnt’ areas as well as generating a six year fire frequency map of the study area. Accuracy assessment of the classified images was carried out using field obtained information on fire occurrence to validate the classification results. An error matrix quantified accuracy of classified maps through producer's accuracy, user's accuracy and overall accuracy. High overall accuracy rates of appromately 96%, in turne, justify use of linear pixel unmixing in identifying and mapping burnt areas. Thus pixel unmixing offers a viable mapping tool for fire monitoring and management in protected areas
Contribution of rainwater harvesting technologies to rural livelihoods in Zimbabwe: The case of Ngundu ward in Chivi District
Water has long been regarded as the main limiting resource for crop production in the drought-prone region of sub-Saharan Africa in which Zimbabwe is located. However, the introduction of novel agricultural technologies such as rain-water harvesting
(RWH) is seeking to mitigate the effects of these perennial droughts. The successful adoption of such technologies has the potential to alleviate problems faced by resource-poor ‘subsistence\' farmers. Thus this paper examines the contribution of RWH technologies to rural livelihoods in Zimbabwe and consequently to the sustainability of agriculture and rural livelihoods
thereof. The methods employed included a questionnaire survey; key informant interviews and field observations. Benefits of RWH technologies found include an increase in agricultural productivity, enhancing household food security and raising of incomes. The technologies also assisted in improving environmental management through water conservation, reduction of soil erosion and resuscitation of wetlands in the study area. The major constraints facing technology adopters were water distribution problems, labour shortage, water-logging during periods of high rainfall and risk of injury to people and livestock as a result of some of the technologies. However, in an area like Chivi where there are frequent droughts and consequently food shortages among smallholder farmers, the benefits of RWH technology adoption seem to outweigh the costs. It was therefore concluded that RWH technologies are suitable for smallholder farmers in semi-arid areas if they are properly tailored to the conditions of the locality where they are promoted. Water SA Vol.32 (3) 2006: pp.437-44
The revitalisation of planning education in Africa: a review of planning education at the Catholic University in Beira, Mozambique
Planning education at the Catholic University of Mozambique consists of undergraduate and post graduate programmes. These programmes aim to provide an overall understanding of the human-environment nexus by addressing physical, economic and human development needs as well as proposing appropriate and effective planning for different regions. The programmes are also part of the institution‟s way of complementing government efforts of decentralization by building the requisite manpower targeted for policy implementation. Of the post-graduate studies, the MSc in Regional Development Planning was introduced in February 2008 while the MSc in Geographic Information Systems (GIS) began in March 2009. In March 2010, the University will introduce a BSc Honours in Regional, District and Town Planning programme. The need to focus education towards development and planning was necessitated by the government's emphasis on decentralisation in planning and management of districts and noted uneven regional development between the north and south of the country. This noted uneven development then entailed the need for capacity building in the planning profession. This paper gives an overview of planning programmes at the Catholic University of Mozambique, Beira. It outlines economic, socio-political and physical environment within which programmes are offered in Mozambique as well as Beira City. Major challenges faced in delivering these programmes are highlighted. It concludes by outlining how regional development and planning programmes in the 21st Century are designed to equip graduates for employment in development oriented research, planning, education and management in both public and private sectors where they can contribute meaningfully to sustainable regional development
The application of geographic information systems (GIS) in the analysis of nutrient loadings from an agro-rural catchment
A large amount of data is usually generated during environmental monitoring programmes. The data need to be transformed into useful information that can be used for interpretation and analysis of problems. This paper outlines the feasibility of using geographic information system (GIS) techniques in the analysis of catchment nutrient yields with the aim of providing a knowledge base for effective decision-making. In this case the spatial and temporal distributions of the nutrient yields in the catchment were analysed. Interpolation with the GIS packages (Arc View Version 3.1 and Arc View Spatial Analyst) enabled the estimation of yields in areas without actual measurement thereof.
(WaterSA: 2003 29(2): 189-194
Improving the understanding of rainfall distribution and characterisation in the Cathedral Peak catchments using a geo-statistical technique
The characterisation of rainfall variability, spatially and temporally, is essential for hydrological and ecological analyses. Inherently, this variability is distinctly more obvious in mountainous areas compared to lowlands. The objective of this study was to ascertain if the use of the regression-Kriging technique would provide improved estimates and understanding of the rainfall distribution across the Cathedral Peak catchments in the Drakensberg escarpment region, South Africa. Findings showed longitude and altitude to be the overall best predictors of the distribution of rainfall for the annual period, wet season and dry season, with longitude explaining 72% and altitude explaining 26% of the rainfall variability for mean annual precipitation, 73% and 26% for the wet season and 50% and 22% for the dry season, respectively. The combination of both longitude and altitude showed a larger coefficient of determination, of 0.73, 0.74 and 0.51, for the annual, wet season and dry season, respectively. Long-term mean annual rainfall patterns showed an overall strong directional distribution from west to east with a distinct pattern observed during the dry season. It was concluded that regression-Kriging is a useful alternative method for characterising rainfall distribution as well as prediction errors for mountainous areas
Retracing Economic Impact of Climate Change Disasters in Africa: Case Study of Drought Episodes and Adaptation in Kenya
Valuation studies have shown that drought occurrences have more severe economic impact compared to other natural disasters such as floods. In Kenya, drought has presented complex negative effects on farming communities. The main objective of this chapter is to analyze the economic impacts of drought and identify appropriate climate change adaptation measures in Kenya. To achieve this objective, an empirical approach, combined with secondary data mined from World Bank Climate Knowledge Portal and FAOSTAT databases, has been used in three main steps. First, historical links between population size and land degradation, temperature and rainfall changes with drought events were established. Second, economic impacts of drought on selected economic indicators such as quantities of staple food crop, average food value production, number of undernourished people, gross domestic product, agriculture value added growth, and renewable water resources per annum in Kenya were evaluated. Third, different climate change adaptation measures among farmers in Makueni county were identified using focused group discussions and in-depth interviews, for which the use of bottom-up approach was used to elicit responses. Findings from the binary logistic regression model show a statistical relationship between drought events and a selected set of economic indicators. More specifically, drought events have led to increased use of pesticides, reduced access to credit for agriculture and the annual growth of gross domestic product. One of the main recommendations of this chapter is to involve farmers in designing and implementing community-based climate change adaptation measures, with support from other relevant stakeholders