| dc.description.abstract | Land degradation and desertification are threatening the livelihoods of millions of people all over the world, especially those living in sub-Saharan Africa. The problem is mainly ascribed to climatic factors, exacerbated by anthropogenic factors such as bad management practices. To combat the problems associated with land degradation and desertification, various approaches and technologies have been developed and implemented by land users, managers and scientists. These approaches and technologies are, however, seldom summarized, analyzed and presented in a single document. This study has been initiated as part of the Desert Margins Program (DMP), which operates in nine countries in East, Southern and West Africa. The DMP aims to determine the causes, extent and severity of biodiversity loss and ecosystem degradation in selected arid and semi-arid regions in Africa. This study has been conducted in concurrence with the objectives identified by the DMP and consists of four parts: (1) an overview of National and International environmental legislation in SA pertaining to land degradation and desertification, and the mitigation thereof, (2) an overview of the approaches and technologies used for the restoration of degraded rangelands in South Africa in the DMP target areas, (3) a summary of conservation, restoration and alternative livelihood technologies used in the nine DMP partner countries, and (4) the evaluation of a drought tolerant grass species (Cenchrus ciliaris), commonly used in restoration technologies in South Africa and other countries. The first part of this study summarized environmental legislation in South Africa concerned with land degradation, conservation and the restoration of natural resources. The country has a comprehensive environmental legislative system that includes a range of International and National legislation. South Africa is also a signatory to a number of International conventions such as the United Nations Convention to Combat Desertification (UNCCD). In accordance with these conventions, various National Action Programs (NAPs) have been developed. Jointly with the NAPs and the Constitution of South Africa, a large number of environmental Acts, such as the National Environmental Management Act (NEMA), form the baseline for conservation and restoration activities in the country. It was, however, observed that, even though efficient environmental legislation is in place, the regulation of the actions set out by the legislation is often problematic and ineffective. The emphasis should therefore be on knowledge transfer and capacity building for all levels of stakeholder involvement to ensure the effective implementation and regulation of environmental legislation. In the second part of the study, the focus was on determining similarities and differences in perceptions about land degradation and desertification, as well as approaches towards the conservation and restoration of natural resources in three different land use systems, i.e. conservation areas, commercial farming and communal or small-holder farming. The study was carried out in the four DMP target areas in the Northern Cape and North West Provinces of South Africa, i.e. Molopo, Kalahari, Namaqualand and Suid Bokkeveld. The majority of land users from all land use types felt that land degradation is characterized by a change in plant species composition, the presence of bare areas and poor condition of livestock. Even though most land users indicated that land degradation is a problem, less than half of them have implemented any conservation and restoration technologies to address the problem. The technology most commonly used by land users from all sectors is resting, while active restoration technologies include the eradication of alien plants, the establishment of wind breaks in croplands and the over-sowing of perennial herbaceous species into natural rangelands. A lack of ownership and financial constraints are the most important factors limiting the adoption and implementation of conservation and restoration technologies in South Africa. The third part of this study investigated approaches and technologies implemented in the different DMP partner countries to mitigate the effects of land degradation and desertification and improve livelihoods. Each of the countries is signatory to one or more international conventions, which has lead to the development of various NAP documents. National environmental legislation in the countries deals with aspects relating to forestry, water, pasture, wildlife and agriculture. The technologies observed in this study have been divided into three different categories, i.e. restoration, conservation and alternative livelihood technologies. In the Southern and Eastern DMP partner countries, technologies have focussed on the conservation and the restoration of natural rangelands, such as resting, dune stabilization and the control of alien invader species. In these countries alternative livelihood technologies such as food gardens and bee keeping have been applied. In an attempt to increase the productivity of the natural resources, technologies in West African DMP partner countries included more restoration and alternative livelihood technologies, such as the Vallerani system and African Market Gardens. The major constraint in the adoption and implementation of all observed technologies is the limited technical and financial resources available to land users. The last part of this thesis dealt with the evaluation of the effects of drought stress on the germination, physiology and morphology of Cenchrus ciliaris. Cenchrus ciliaris is a popular cultivated pasture in semi-arid and arid areas and is often used in over-sowing technologies in South Africa and other African countries, as concluded from the previous parts of the study. Extreme environmental conditions however regularly hamper the germination, establishment and growth of this species. Seed of C. ciliaris was used in three different laboratory and glasshouse experiments. The laboratory experiments showed that the germination capacity decreased with an increase in drought stress. In addition, the seedlings suffered decreased morphological development of roots and stems. The physiological measurements taken on mature plants indicated that, even though this species showed sensitivity to drought stress, no significant changes occurred. It is therefore concluded that drought conditions negatively influenced germination, seedling establishment and morphology, while it had very little effect on the physiological processes of mature plants. This study provides a baseline document, summarizing information concerning legislation and technologies used for combating land degradation and the improvement of livelihoods. The information gained through this study can give land users the necessary 'know-how' to apply these technologies in their specific situations. It is, however, essential that the results of this research are implemented over the long-term as this would facilitate the adoption and implementation of the 'best-bet' technologies identified by this study. | |
