The complexities of the dynamics involved in the onset and progression of land degradation complicate its assessment. The health impacts of desertification and drought pdf, 1. Nine main causes of land degradation are as follows. Degraded soil diminishes food production and leads to soil erosion, which in turn contributes to desertification. Pdf the impact of soil erosion as a food security and. Land degradation classes biophysical land degradation classes are identified by the combination of the overall status in provisioning biophysical ecosystem services and the trend of these services biomass, soil, water and biodiversity as described above. Cornelis encyclopedia of life support systems eolss desertification is generally viewed as an advanced stage of land degradation mainly occurring in the arid, semiarid and dry subhumid areas of the world. The combined reclassification is shown in the following map and table figures 4 and 5. It indicates the latitude, longitude and elevation of any point. An essential assessment of the current land degradation status. The united states of america, katharine vincent south africa. Figure 2 shows a regional african extent of the problem. Causes and impacts of land degradation and desertification. Africa latitude and longitude and relative locations.
A land degradation assessment and mapping method horizon ird. Land degradation the process of land degradation in southern africa is blamed on water and wind erosion, sedimentation, longterm destruction of vegetation and diminution of the bioresources. Working for land, working for wetlands, working on fire, landcare and national forestry programme. What is affecting our environment 29 what is affecting our environment 29 commonly, the relationship between human settlements and the environment is considered to be linear figure 3. Uptodate, quantitative information is needed to support policy and action for food and water security, economic development, environmental integrity and resource conservation. Desertification goes hand in hand with accelerated soil erosion. The natural factors are largely associated with climate variability especially droughts, while some human activities in the drylands is the major cause, especially in africa. Erosion frequently leads to the formation of badland features on. There has been outright loss of natural habitat, over 18 per. Eastern africa including ethiopia has experienced moderate to severe land degradation problems as shown in. Pdf the impact of land degradation on the quality of. Economics of land degradation in subsaharan africa. Defining land degradation and improvement land includes not only the soil resource, but also the water, vegetation, landscape, and microclimatic components ofan ecosystem land degradation refers to a temporary or permanent decline in the productive capacity ofthe land,2 or its potential for environmental management. Agricultural land makes up about 100 million hectares.
Mapping degradation in the terrestrial environment. University of cape town press, cape town, south africa. Experiences from the south african land degradation. Figure 1 shows global extent of droughts and desertification. Lines of latitude are often referred to as parallels. Land degradation is a global environment and development issue. Regional assessment of soil changes in africa south of the sahara. The worst situations can be found in africa, which is threatened because the land degradation processes affect about 46 percent of the whole continent and create a health risk to people living in the regions far beyond the affected areas. The term land degradation involves both soil and vegetation degradation. The aim of this paper is to reassess the land degradation and desertification problem in south africa. There has been an increase in land degradation and biodiversity loss in south africa. Land degradation and improvement in south africa 1. Land degradation, caused by soil erosion and deforestation, presents an obstacle on agriculture hence threatening the.
This is particularly worrisome since, according to the uns food and agriculture organization, some 83% of subsaharan african people depend on the land for their livelihood, and food production in africa will have to increase almost 100. Land degradation the process of land degradation in southern africa is blamed on water and wind erosion, sedimentation, longterm destruction. Land degradation in south africa is a significant environmental problem throughout the whole country meadows and hoffman, 2002. Pdf land degradation and soil erosion in the eastern highlands. An assessment of land degradation in the save catchment of. The nature, extent and causes of land degradation in south. Land degradation in subsaharan africa ssa is believed to be expanding at an alarming rate, accompanied. Land degradation here mainly refers to the loss of lifesupporting land resource through soil erosion, desertification, salinization, acidification, etc. Pdf land degradation impact on soil organic carbon and nitrogen. The ipbes assessment report on land degradation and restoration. Chapter 6 land department of environmental affairs.
Multifunctional utilisation of vegetation resources contributes to contemporary land cover changes in the peripheral high mountain region of southern africa. The human dimension of desertification in the drylands of. In this report, land degradation is defined as a negative trend 4 in land condition, caused by direct or indirect humaninduced processes. Ethiopia, situated in horn of africa, has an area of about 1. Many of these are in africa, acknowledging the severe. Young 1998 observes the lack of techniques to assess the extent and severity of land degradation. Desertification unccd as land degradation in arid, semiarid and dry subhumid areas through natural processes as well as human activities. The northeastern corner of the country lies within the tropics, astride the tropic of capricorn. Understanding the interactions between climate and land degradation. Desertification, a phenomenon referring to land degradation in arid, semiarid and dry subhumid regions as a result of climatic variations and human activities, is considered as one of the most severe environmental and socioeconomic problems of recent times.
Final submission land degradation in the limpopo province 1 c. Human activities include overcultivation, overgrazing, deforestation, poor irrigation practices and any other inappropriate land use and human management of ecosystems. Land degradation isaslow decline inalands productivity, forwhatever reason. The map of the study area is presented on the next page.
Forests play an important role in maintaining fertility of soil by shedding their leaves which contain many nutrients. Land degradation and ecosystem services uzh department of. In this linear system, nature provides inputs to the human. Land degradation impact on soil organic carbon and nitrogen stocks of sub tropical humid grasslands in south africa. These resources contain literature on water, soil and veld degradation in both commercial and communal areas of south africa. South africa is especially susceptible to iaps and this is nationally perceived as the countrys greatest land degradation threat, partly because it reduces national streamflow by 2. Land degradation can be viewed as any change or disturbance to the land perceived to be deleterious or undesirable eswaran, 2001. Indigenous peoples of africa coordinating committee. Land degradation is, usually, the result of complex interrelationships between biophysical and socioeconomic issues which affect many people and their land, specially in the tropics and developing countries.
The designations employed and the presentation of material in this information product do not imply the. Pushpam kumar, unep coordinator and technical editor. A new international report makes for bleak reading on the state of the worlds soils. Also, the most important socioeconomic reasons for land degradation.
It is based on the national land cover 2000 supplemented with more recent data from provinces and other sources where available. The country has a wide range of interrelated environmental and development challenges existing in a sociopolitical context recently subject to substantial change. It predicts that land degradation will displace up to 700 million people worldwide by midcentury. South africa has a land area of 122 million hectares. Subsaharan africa ssa has experienced the most severe land degradation in the world. Forests are also helpful in binding up of soil particles with the help of roots of vegetation. This book is an accessible summary of a technical report on land degradation and also discusses the impact of apartheid land division policies on the country as a whole. National level lada south africa and 5 other countries catchment level ewt riverine rabbit program in. Iii humaninduced land degradation donald gabriels, wim m. The impact of land degradation on the quality of soils in a south. Land degradation in south africa 745 while our study has obvious implications for policy, we were not commissioned to produce a policy document for the nap process. Deforestation accounts for the major land degradation problem as it results in severe soil erosion, flood, and loss of fertile soil. The fynbos and grassland biome are exceptionally vulnerable to iaps.
Dr c seymour sanbi, dr a skowno sanbi university for registration. Land degradation and improvement in south africa i main points 1. Forests, rangelands and climate change in southern africa. Given that livelihoods of the majority of the rural poor heavily depend on natural resources, countries in the region have designed a number of policies and strategies to address land degradation and to enhance productivity. With a population of 80 million, ethiopia is the second most populous country in africa argaw, 2005. Only 14% of agricultural land is suitable for crop production while the remainder is used for extensive grazing, forestry and nature conservation7. Unesco eolss sample chapters land use, land cover and soil sciences vol. In the past, much of the blame for land degradation has been placed on. South africa has a long history of desertification research which stretches back to the last century. Unlike previous investigations into land degradation in south africa this analysis suggests that climatic conditions, especially those since the late 1970s, might have had a more important influence on land degradation patterns in south africa than is currently appreciated. Land coveruse system developed for south africa 8 3. Results indicate that land degradation decreased soil aggregate stability. The principal aim of this study was to explore the impacts of desertification, degradation and drought on both the natural resources.
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