An assessment of the soil resources of africa in relation. The material moved by erosion is called sediment 3. Farmers from netherlands, france, and other european countries that settled in south africa became known as. Spatial and temporal aspects of soil erosion in mt ayliff. However, such quantitative data is available only from a few sites. Soil erosion is one of the unresolved problems of rural agriculture.
Soils of the limpopo river basin limpopo river awareness kit. Status and priorities of soil management in south africa liesl wiese 6 december 2012. North africa faces a great environmental problem caused by the erosion of fertile soil, a process known as. South africa, namibia and botswana and preland reforms zimbabwe. Key regional studies of soil erosion in south africa. An extreme storm event in march 2007 resulted in substantial damage to infrastructure and. Sateec estimates soil loss and sediment yield within river catchments using the revised universal soil loss equation rusle and a spatially distributed sediment delivery ratio. The proportion of an 1800 km 2 study area in the middleveld classified as high erosion class has increased from 6. In south africa rates of rill erosion have only been measured in association with sheetwash see above, but gullies, unless they are stabilised, may erode headwards or from the walls very rapidly and large sediment loads are common. Lines of latitude are often referred to as parallels. Slr in namibia and south africa 8 and regional impacts of climate change in the western cape 9 have recently been completed. Due to the absence of reliable data at appropriate resolution and differences in the methods used, there are discrepancies in soil erosion estimates at both continental and basin levels. A case study in the denku microwatershed oromia region by kassu kebede beyene submitted in accordance with the requirement for the degree of masters in human ecology at the university of south africa supervisor. Africa is a vast continent with a tremendous resource endowment and offers great potential for increased agricultural productivity fao, 1993.
Before rehabilitation begins, the cause of sheet erosion at a site needs to be understood and dealt with. The zandrivier deposit, pietersburg green belt, south. It is also participating in oecd work on base erosion and profit shifting. The impact of soil erosion on agricultural potential and. Land degradation in south africa is a significant environmental problem throughout the whole country meadows and hoffman, 2002. Effects of soil erosion on soil properties as related to. Large areas of africa are at present prone to soil erosion, although the actual rates of soil loss vary greatly from as little as 0. Monitoring soil erosion in south africa at a regional. Many of the policies that were implemented by the state have not been effective in reducing the rate of soil loss. The slope length and the amount of soil erosion have always been proportional to the steepness of the slope. This study is concerned with the physical and human causes of soil.
The deposit is unusual for an archaean mesothermal gold lode in southern africa with respect to the abundance of tourmaline rock that hosts large. A coastal vulnerability index for kwazulunatal, south. Soil erosion occurs when soil is removed through the action of wind and water at a greater rate than it is formed soil. This paper examines the soil loss spatial patterns in the keiskamma catchment using the gisbased sediment assessment tool for effective erosion control sateec to assess the soil erosion risk of the catchment. The south african context south africa is a nonmember with enhanced engagement with the oecd5 and an observer to the oecds committee on fiscal affairs. Some quantitative information on the magnitude of soil erosion for different ecoregions in south africa is available. This must of necessity be an important factor, and in mountainous country it is often only by reason of a strong vegetal mantle or artificial means that the soil, no matter what its nature, is kept in place at all. Wind erosion and aeolian deposits wind erosion is considered the major cause of irreversible land degradation in the arid environment of abu dhabi emirate where dry, noncohesive sandy soils, poor vegetation cover, strong wind, and hyperarid conditions prevail.
The 19 bantu land act and the development and trust land act of 1936 had the. The impact of soil erosion on both the environmental and social wellbeing of communities in east africa is to be explored in new research led by the university of plymouth. The dominant soil types in the limpopo river basin are generally broken down into two main groups older soils that have formed from deep weathering of parent material examples of such deeply weathered, old sediments are the soils occurring on the highveld plateaus of south africa and zimbabwe. Pdf the impact of soil erosion as a food security and. The secondary aim of the study was to determine whether combining the three independent variables and using a multivariate analysis. Protect the soil by controlling erosion farmers weekly. Soil erosion risk assessment of the keiskamma catchment. Soil erosion in maasai heartlands in tanzania photograph. Previous research indicates that over 70% of the countrys surface has been affected by varying inten. Soil erosion in south africa south africa is characterized by a wide biodiversity and distribution of the natural resources soil, climate, water and vegetation. Soil erosion is one of the major forms of land degradation in subsaharan africa ssa with serious impact on agricultural productivity.
Hudson observed that in simplest terms steep land is more vulnerable to water erosion than flat land for reasons that erosive forces, splash, scour and transport, all have greater effect on steep slopes. The paper investigates the relationship between geology, soils and slope aspects in four ciskei catchments. The highly exposed south african predominantly sandy coastline is going to be susceptible to increased erosion by wind, wave processes etc due to the expected increased storminess. Soil erosion generally is a function of slope attributes. Posteuropean settlement impacts on erosion and land degradation. Erosion frequently leads to the formation of badland features on. Three of south africa s major coastal cities, durban 1014, cape town 15 and port elizabeth have embarked on studies to understand and address these impacts. Terrain slope, soil characteristics, land use and climate have all been shown to be influential in their. South africas current responses to the challenges posed by base erosion. The kwazulunatal kzn coast, south africa, has experienced significant coastal erosion and damage from extreme storm events, which could be indicative of what is to come for this province given climate change predictions. In such areas the fall of the streams and rivers is rapid and.
If agricultural performance is measured in terms of per capita food production, there has been an alarming decline in the last few decades according to the world resources. Erosion is the process by which rocks and soil are transported from one location to another. Structured interview scheduled was used to collect data from 50 respondents using simple random sampling. Monitoring soil erosion in south africa at a regional scale.
Annually, were still losing an estimated 500 million tons of sediment, composed of mainly soil and topsoil. Sumnerc introduction soil erosion is a major problem confronting land resources throughout south africa. 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. Generally, in south africa, alien species require more water than the indigenous one. What aspect of africas physical geography drew european nations to want to colonize africa in. Badland and gully erosion in the karoo, south africa. Authordate location description key findings 1 talbot 1947 swartland sandveld, w cape air photo analysis of extent and type of erosion poor farming practices had resulted in wind and runoff erosion 2 scott 1951 kzn drakensberg soil loss. Department of agriculture directorate land use and. 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. Sheet erosion frits van oudtshoorn of the modimollebased africa land use services explains that the aim of sheet erosion restoration is to establish vegetation that protects the soil and then allows natural regeneration processes to take over. One objective of this thesis is to add to the existing data.
Without soil and plants the land becomes desertlike and unable to support life. In international symposium on sediment dynamics in changing environments, december 15, 2008, christchurch, new zealand. Since lindeques article in 2010, south africas erosion problem hasnt significantly worsened, but it has also not improved. Soil erosion, policy and peoples perceptions in a rural. The location of the surveyed area can be seen in figure 8. The distribution of soil erosion as a function of slope. Study of sand mining and related environmental problems. Once this nutrientrich layer is gone, few plants will grow in the soil again. How is south africa responding to growing concerns about. Considerably younger, shallower sediments from more recent erosional activities or deposited.
A number of political developments in the political and socioeconomic geography of south africa have helped to exacerbate soil erosion. A perspective on sea level rise and coastal storm surge. Geographic distribution of major erosion surfaces although multiplicity of erosion surfaces has been recognized in central africa, workers within the past two decades have demon strated that most of the landforms can be referred to a relatively small number of major erosion surfaces. Gravity pulls everything to the center of the earth gravity causes sediment, water and other material. Estimating soil erosion in subsaharan africa based on. The zandrivier mine on mount mare in the pietersburg greenstone belt exploited a goldbearing, arsenical tourmalinite that formed during episodes of ductile and brittle deformation associated with d 2 tectonism along the snymansdrift shear zone. Soil erosion, desertification and farming in southern africa. This study investigates the impact of soil erosion on the agricultural potential and performance of sheshegu community farmers in the eastern cape of south africa. An assessment of the soil resources of africa in relation to productivity. The nature, extent and causes of land degradation in south.
Status and priorities of soil management in south africa. As indicated by the classification in table 121, the texture of these soils is similar to fayette soils, but these soils differ by having a fragipan. This strategy is designed to reduce the potential impacts of crop. Causes of soil erosion erosion occurs when farming practices are not compatible with the fact that soil can be washed away or blown away. This study attempts to contribute to the existing regional soil erosion. Its surface area is 122 million ha, of which almost 86% is used for agriculture, 74% being natural veld and 14. Africa latitude and longitude and relative locations. Soil is formed at a rate of only 1 cm every 100 to 400 years and it takes 3 000 to 12 000 years to. Here farmers use a mixed farming system, keeping goats, sheep and cattle as well as growing crops.
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