Browsing Environmental Science by Title
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Areola, O.; Dikinya, O.; Mosime, L. (Global Science Books, http://www.globalsciencebooks.info/Journals/AJPSB.html, NaN, 2011)[more][less]
Abstract: This study compares soil quality parameters, and salinity and heavy metal levels in soils cultivated with different crops under secondary treated wastewater irrigation in the Glen Valley, near Gaborone City, Botswana. The hypothesis being tested is that the impact of wastewater on soil quality varies with soils and crop types. The study covers 4 selected crops, maize (Zea mays L.), spinach (Spinacia oleracea), olive (Olea europaea), and tomato (Solanum lycopersicum), most widely cultivated by the farmers. Three farm plots per crop type were sampled at 5 sampling points and at two soil depths, 0-15 and 15-30 cm. Samples were also collected at 5 sampling points from two control sites. Irrigation water samples were collected from microbiological analysis from 2 farms per crop type. The most significant differences and relationships are between those crop farms, such as maize and two of the spinach plots, with predominantly sandy soils (loamy sands – sand loams) on the one hand, and the olive, tomato and one of the spinach plots with sandy clay loams on the other. The importance of soil texture was confirmed by the strong correlations between the sand and silt contents, several soil quality parameters, heavy metals and other elements. With the exception of Cd and Hg, most soil heavy metal contents were lower on the irrigated plots than on the control plot. The EC values also show that soil salinity levels were still low on the irrigated fields, but SAR and ESP values were high. The secondary treated wastewater being used in the Glen Valley is biologically clean, but one recorded case of E. coli emphasizes the importance of avoiding sprinkler irrigation at all costs to protect human health. URI: http://hdl.handle.net/10311/1002 Files in this item: 1
Dikinya_AJPSB_2011.pdf (249.7Kb) -
Mbaiwa, J. E.; Ngwenya, B.N.; Kgathi, D.L. (Blackwell http://www.wiley.com/10.1111/j.1467-9493.2008.00332.x, NaN, 2008)[more][less]
Abstract: This paper reviews how state policy and regulatory instruments, including protected area alienations and concessions, have altered or denied the access to land and natural livelihood resources of the indigenous Basarwa and minority subsistence-oriented communities in the Okavango Delta (OD) in Botswana. Drawing on field research and guided by a sustainable rural livelihoods framework, the paper provides an overview of key institutional interventions – in particular the setting up of the Moremi Game Reserve, Wildlife Conservation Policy, Tourism Policy, Agricultural Development Policy and the erection of veterinary fences – that have served to privilege a foreign-owned and dominated commercialized wildlife and nature tourism sector and the export-oriented beef industry in the OD. The officially sanctioned barriers to customary and usufructory rights and access, and the non-recognition of historically embedded traditional land uses have decimated already marginalized resource-based subsistence livelihoods, and precipitated intergroup conflicts over preferential rights and access to resources and opportunities, notably wildlife, non-timber veld products, agriculture and community-based tourism schemes. Such outcomes, moreover, will have consequences for the longer-term sustainability of the OD both as a socioeconomic resource base and as a natural ecosystem. URI: http://hdl.handle.net/10311/483 Files in this item: 1
Mbaiwa_SJTG__2008.pdf (966.6Kb) -
Mbaiwa, J.E.; Sakuze, L. K. (Taylor and Francis http://dx.doi.org/10.1080/14766820902829551, NaN, 2009)[more][less]
Abstract: This paper uses the livelihoods framework to analyse how cultural tourism can diversify livelihoods at XaiXai village in the Okavango Delta, Botswana. Both primary and secondary data sources were used in this study. Primary data sources included household and key informant’s interviews conducted at XaiXai village and Gcwihaba Caves. Secondary data included both published and unpublished materials on cultural tourism, XaiXai village and Gcwihaba Caves. Results indicate that the San(Basarwa) of XaiXai’s traditional life of hunting and gathering has become a cultural tourism product in the Okavango Delta. Gcwihaba Caves’ geological formation particularly the stalagmites, stalactites and channels also attract tourists that visit the Okavango Delta. The caves also have a cultural history in that they were used as a hiding place by the Basarwa in times of wars, rainy season and cold winters. As such, the cultural values of the San of XaiXai and Gcwihaba Caves are cultural tourism products that can diversify livelihoods at XaiXai village. Therefore, policies and strategies that address cultural tourism and rural livelihoods in tourism destination areas need to be developed. The Gcwihaba Caves and Xaixai Village case study demonstrates that cultural tourism can be a tool for rural livelihoods diversification in tourism destination areas of developing countries. URI: http://hdl.handle.net/10311/482 Files in this item: 1
Mbaiwa_JTCC_2009.pdf (899.2Kb) -
Meck, M.; Atlhopheng, J.; Masamba, W.R.L. (Elsevier http://www.linkinghub.elsevier.com/retrieve/pii/S1464343X09000491, NaN, 2009)[more][less]
Abstract: Alkaline rocks (phosphate deposits in particular) of igneous origin are currently being mined in Zimbabwe. Exploitation of these deposits, which are associated with metals and non-metals, provides a potential for changing the river water quality in the surrounding areas by increasing metal and phosphates levels in the water, thereby endangering the beneficial use of the river. The aim and objectives of this paper are to enumerate the current impacts associated with mining alkaline rocks on Save River water quality in Zimbabwe using the Dorowa mine as a case study. Though there are several impacts associated with the mining of alkaline rocks, this paper deals only with impacts on water quality. A preliminary assessment of the water quality in the Save River downstream of the Dorowa phosphate mine showed an increase in conductivity, iron content, manganese content, nitrates and hardness when compared to those taken before mining activity began. However, there was no notable increase in phosphate and metals except for Fe and Mn. A plausible explanation for the low phosphate values in the water is that the phosphates are precipitating and settling as sediments. Phosphate is known to effectively remove metals from the surface water through the formation of metal–phosphate minerals. Thus, various pollutants may be adsorbed into sediments accumulated on the bottom of the river. These sediments may accumulate pollutants over long periods and act as new pollutant sources to the overlying water when phosphate desorbs from sediments due to changes in water conditions. Therefore, the sediments can act as a source of water pollution in the future URI: http://hdl.handle.net/10311/409 Files in this item: 1
Meck_JAES_2009.pdf (495.8Kb) -
Dikinya, O.; Hinz, C.; Aylmore, G. (Elsevier http://www.linkinghub.elsevier.com/retrieve/pii/S0016706108001365, NaN, 2008)[more][less]
Abstract: The dynamics of the process of self-filtration in soil columns have been evaluated for two soils with different structural cohesion (Balkuling agricultural soil and a mining residue) by carrying out experiments focusing on microscopic particle behaviour during filtration. Soil column experiments were set up to simultaneously measure changes in hydraulic gradients (ΔH/ΔL) along the columns and outflow particle sizes and concentrations during pressure leaching with solutions of 100, 10 and 1 mmol/L NaCl and deionised water. The lowest ionic strength has resulted in more reduced hydraulic conductivity and relatively more release of colloids associated with hydrodynamic shear and dispersion. Steady increases in hydraulic gradient (ΔH/ΔL) and corresponding decreases in relative saturated hydraulic conductivity (K/Ko) with time were observed for both soils and follow similar trends at all column depths. The most severe increases in ΔH/ΔL and decreases in K/Ko always occurred near the inlet to the columns and the decline gradually decreased along the column. The decrease in K/Ko and increase in ΔH/ΔL were clearly influenced by the size as well as the concentration of migrating particles in the porous medium. The finer mobile particles in the mining residue were clearly more readily self-filtered at the lower concentration than the larger Balkuling soil particles producing more rapid increases in ΔH/ΔL and decreases in K/Ko. This was attributable to more effective self-filtration and more pore clogging probably due to increased development of the diffuse double layer, swelling and dispersion within the soil matrix at these concentrations. URI: http://hdl.handle.net/10311/488 Files in this item: 1
Dikinya_Geoderma_2008.pdf (1.429Mb) -
Bernard, T.; Moetapele, N. (Elsevier http://www.doi:10.1016/j.jaridenv.2005.02.001, NaN, 2005)[more][less]
Abstract: For at least 200 years, Gomoti River people and their neighbours lived interactively with the Okavango flood pulse system, travelling widely in dugout canoes, practicing flood recession agriculture, fishing, hunting, and collecting wild foods. Today they are wetlanders without wetlands. A major outflow channel of the eastern Okavango Delta in the 1930s, the Gomoti River rarely flows these days. This paper explores the Gomoti’s demise, through the lenses first of science and second of Gomoti basin residents. Models developed over the past 20 years attribute the Gomoti’s drying to a complex set of bio-hydrologic processes and feedback loops that begin with sedimentation and conclude with channel switching, peat fires, and purging of toxic salts. Such models essentially omit the long history of human habitation and ecological interaction with the delta. Local people, on the other hand, tell of deliberate and systematic management of channels and floodplains, and they argue this management kept the river healthy and flowing. The picture is confounded by colonial era interventions and by Botswana government policies partitioning the Gomoti and restricting access to its headwaters. We conclude with a model combining meso-scale scientific explanation with micro-scale indigenous constructions as a context for new thinking about Okavango Delta resource management. URI: http://hdl.handle.net/10311/467 Files in this item: 1
Bernard_JAE_2005.pdf (2.556Mb) -
Toteng, E.N. (Routledge http://dx.doi.org/10.1080/02508060802475415, NaN, 2008)[more][less]
Abstract: This article examines the adverse effects of a fragmented water management framework and the role of domestic water users on water conservation in Gaborone, the rapidly growing capital city of Botswana. There was a major drought in Botswana in 2004, which recurred in 2007. The drought seriously affected water availability in Gaborone, re-igniting the water conservation debate. Most urban households prior to 2004 did not practise water conservation, except in cases of enforced temporary measures, such as water restrictions and increased water tariffs imposed by the Water Utilities Corporation. From secondary evidence, the situation had not changed much in 2007. URI: http://hdl.handle.net/10311/363 Files in this item: 1
Toteng_WI_2008.pdf (851.6Kb) -
Mbaiwa, J.E. (Elsevier http://www.doi:10.1016/j.tourman.2003.11.005, NaN, 2005)[more][less]
Abstract: This paper draws on the dependency paradigm to explain the development of enclave tourism and its socio-economic impacts in the Okavango Delta, Botswana. Using both primary and secondary data source, the study indicates that international tourists, foreign safari companies and investors dominate the tourism industry in the Okavango Delta. The foreign domination and ownership of tourism facilities has led to the repatriation of tourism revenue, domination of management positions by expatriates, lower salaries for citizen workers, and a general failure by tourism to significantly contribute to rural poverty alleviation in the Okavango region. Tourism as a result has a minimal economic impact on rural development mainly because it has weak linkages with the domestic economy, particularly agriculture. Because of its nature, tourism in the Okavango Delta cannot be described as being sustainable from a socio-economic perspective. In order to address problems of enclave tourism development and promote more inclusive and beneficial tourism development in the Okavango, there is need to adopt policies and strategies that will ensure that substantial amounts of tourism revenue are retained in the Okavango and Botswana. These strategies should also ensure that tourism development in the Okavango Delta has strong linkages with the rest of the economy in Botswana. URI: http://hdl.handle.net/10311/429 Files in this item: 1
Mbaiwa_TM_2005.pdf (2.402Mb) -
Gwebu, T.D. (Kluwer Academic Publishers, http://www.springerlink.com/content/102895/, NaN, 2002)[more][less]
Abstract: Like most African countries, Botswana contributes almost insignificantly to global greenhouse emissions (GHGs). In this context, some have argued that energy policy and legislative measures to regulate emissions in Botswana should not be accorded high priority. This is a misguided view when one considers that each country, no matter how under-industrialized, contributes to the overall global emission problem. Moreover, the least developed countries will have to industrialize in order to meet the increasing economic and social needs of their growing populations. For rapidly growing economies like Botswana, whose annual energy demand is projected to increase by about 4% for the next ten years, the importance of compiling accurate inventories of sources and sinks of GHGs and formulating environmentally-friendly policies can hardly be over- emphasized. The United Nations Framework Convention on Climate Change (UNFCCC) provides the ideal basis for the country-by-country investigations and management of global climatic change; specifically its nature, properties, directionality, characteristics and probable consequences. Botswana was a founding signatory of UNFCCC in 1992 and ratified the Convention in 1994. The country is also involved in regional cooperation efforts, within the Southern African Development Community, to enforce regulatory mechanisms to minimize GHG emissions from the energy sector. There exist certain energy-related institutions, policies, and regulations in the country which could mitigate the impact of GHG emissions on global warming. This paper, based on government and other relevant documentation, critically analyses Botswana’s energy sector policies in as far as they affect climate change. It is clear that much still needs to be done about energy policies in terms of proper formulation, monitoring, co-ordination, energy pricing and the exploration of energy alternatives to mitigate potentially negative impacts on climate change. URI: http://hdl.handle.net/10311/958 Files in this item: 1
Gwebu_GJ_2002.pdf (1.010Mb) -
Totolo, O.; Chanda, R. (Elsevier Science Ltd, http://www.elsevier.com/wps/find/journaldescription.cws_home/622855/description#description, NaN, 2003)[more][less]
Abstract: The collection of papers in this special edition of the Journal of Arid Environments is a sequel to a Workshop held in Maun, Botswana, in October 2000, on the theme Climate Change, Biodiversity and Multi-species Production Systems in the Kalahari Region. Constituting only about one-third of the workshop papers delivered, this set of articles survived a rigorous peer-review process and are being published as one of the planned outputs of the Maun meeting. Except for the keynote paper by Darkoh which is a review article with a continental purview, the collection is based on research conducted by natural and social scientists within the Southern African Kalahari region either as part of the Southern African Science Initiative (SAFARI 2000) co-ordinated from the University of Virginia in the U.S.A. or of the Kalahari Transect project based at the University of Botswana. URI: http://hdl.handle.net/10311/316 Files in this item: 1
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Gwebu, T.D. (Pergamon, www.elsevier.com/locate/habitatint, NaN, 2003)[more][less]
Abstract: This study investigates the profile, dynamics and dimensions ofenvironm ental problems at Old Naledi, a low income urban neighbourhood in Gaborone, the capital city ofBotsw ana. It is based on documentary and field research. The field research has a participatory component involving meetings, discussions and open- ended interviews with the interested and affected persons. It also involves the administration of a structured survey questionnaire to 171 resident respondents. The main findings ofthe study are that residents have made great efforts in improving the availability of the housing stock. However, in the process they have failed to abide by the stipulated Development Control code and Urban Development Standards. This essentially reflects the increasing non-affordability of land and costs of construction materials to urban low income groups due to evolving state policy in the provisioning ofshelt er. The direct result has been a congested, overcrowded settlement. Because ofthis , and a rapidly increasing population, there has been underservicing and the emergence oflif e-threatening home and neighbourhood environmental problems. URI: http://hdl.handle.net/10311/496 Files in this item: 1
GWEBU2003Environmental Problems.pdf (2.409Mb) -
Gumbricht, T.; Wolski, P.; Frost, P.; McCarthy, T.S. (Elsevier http://www.doi:10.1016/j.jhydrol.2003.11.010, NaN, 2004)[more][less]
Abstract: The pristine Okavango Delta wetland of northern Botswana is potentially under threat due to water abstraction from its tributaries. We have developed a statistical model which makes it possible to predict the extent of wetland loss which will arise from water abstraction. The model also permits prediction of the maximum area of flooding, and its spatial distribution, three months in advance of the flood maximum. The model was calibrated using maximum areas of seasonal inundation extracted from satellite imagery covering the period 1985–2000, which were correlated with rainfall and total flood discharge. A technique was developed to translate the modelled flood area into a flood map. The methodology can predict maximum area of flooding and its distribution with better than 90% accuracy. An important, although relatively minor, source of error in the spatial distribution of the flood arises from a secular change in flood distribution in the distal Delta which has taken place over the last 15 years. Reconstruction of flooding history back to 1934 suggests that the Delta may be subject to a quasi 80 year climatic oscillation. If this oscillation continues, the extent of flooding will increase in the coming decades. URI: http://hdl.handle.net/10311/428 Files in this item: 1
Gumbricht_JH_2004.pdf (1.267Mb) -
Mubyana, T.; Krah, M.; Totolo, O.; Bonyongo, M. (Journal of Arid Environments. http://www.elsevier.com/wps/find/journaldescription.cws_home/622855/description#description, NaN, 2003)[more][less]
Abstract: The effect of flooding on soil total nitrogen, phosphorus and microbial population in different vegetation zones (floodplain, island and woodland) and profile depth (0?1, 0?5, 2?0, 3?0, 4?0 and 5?0m) of the Okavango Delta was studied from February to July 1999. Total nitrogen significantly differed with soil profile depth, moisture regime and months. In the woodlands, insignificant total nitrogen was detected at all depths except at 0?1m, where 0?03% and 1?17% were detected in February and March, respectively. In the island samples, only 0?05% was detected at 4m in February. Nitrogen in the floodplain samples was concentrated in the A1 horizon where 0?12%, 0?61% and 0?03% were detected in February, March, and May, respectively. Organic phosphorus significantly differed with vegetation zone but not with months and depth. Although organic phosphorus was low (0?02–0?52%) at all sites, it was liberally distributed throughout the profiles. On the island, actinomycetes were only detected up to 2m in February and up to 3m in July. Fungi concentrated in the top 0?5m (103–105). In both the floodplain and island samples, bacteria concentrated in the upper 3m. However, after May, populations decreased significantly. In the floodplain, significant actinomycetes populations were only detected in the upper 0?5m. Generally, organic phosphorus showed positive correlations with fungal populations. This study indicates that these soils are low in total nitrogen and phosphorus. URI: http://hdl.handle.net/10311/293 Files in this item: 1
Influence of seasonal flooding.pdf (3.953Mb) -
Dikinya, O.; Hinz, C.; Aylmore, L.G. (Csiro, http://www.publish.csiro.au/nid/84.htm, NaN, 2007)[more][less]
Abstract: The paper examines the effects of electrolyte concentration and sodium adsorption ration (SAR) on the relative saturated hydraulic conductivity (RHC) and the ionic behaviour of calcium (Ca) and sodium (Na) ions in the Na-Ca echange complex. Batch binary exchange and saturated column transport experiments were carried out to quantify these effects using agricultural Balkuling soil and mining residue. Generally, RHC has been found to decrease with time, with increasing SAR and with decreasing electrolyte concentration. The more rapid decrease in RHC in the mining residue, particularly at the lowest concentration (1 mmol/L), was consistent at all SAR values. The decreases in RHC were likely to be caused by partial blocking of pores by dispersed clay particles, as evidenced by the appearance of suspended clay particles in the effluent during leaching. Significant differences in RHC were abserved in the passage of fronts of decreasing electrolyte concentration for CaCl2 and SAR 15 solutions through the soil columns. These differences were attributable to structural alterations (slaking) of the media and the nature of the particles released and mobilised within the porous structure at a given point in the column. Measurements at the critical threshold concentration and turbidity increase in SAR to 15 is initially accompained by erractic RHC, presumably due to the break up of soilaggregates under the increased swelling forces. The less coherent mining residue soil was substantially more vulnerable to blockage of pores than the Balkuling soil in which clay particles are likely to be more readily mobilised, and hence available to re-deposit and occlude the matrix pores. URI: http://hdl.handle.net/10311/312 Files in this item: 1
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Kgathi, D.L.; Bolaane, B. (Sage http://wmr.sagepub.com/cgi/content/abstract/19/4/342, NaN, 2001)[more][less]
Abstract: Sustainable solid waste management is a strategy for achieving environmental quality in both the developed and the developing world. Environmental quality is a necessary condition for an increase in per capita welfare over time. The paper suggests alternative instruments for solid waste reduction, re-use and recycling. But to be able to apply the suggested economic instruments, the quantities and composition of the waste must be known. Having identified the current instruments of Botswana’s solid waste management (regulatory measures, environmental education, and economic instruments of property rates, service levy, and sanitation fees), the paper argues that these do not go far enough in enhancing environmental protection. Alternative instruments such as solid waste collection and disposal levies, deposit refund schemes, and product levies are suggested. It is also suggested that public environmental education and regulatory measures should be strengthened. URI: http://hdl.handle.net/10311/480 Files in this item: 1
Kgathi_WMR_2001.pdf (1.278Mb) -
Swatuk, L. A.; Rahm, D. (Elsevier, http://www.linkinghub.elsevier.com/retrieve/pii/S1474706504001834, NaN, 2004)[more][less]
Abstract: Botswana is generally regarded as an African success story. Nearly four decades of unabated economic growth, multi-party democracy, conservative decision-making and low-levels of corruption have made Botswana the darling of the international donor community. One consequence of rapid and sustained economic development is that water resources use and demands have risen dramatically in a primarily arid/semi-arid environment. Policy makers recognize that supply is limited and that deliberate steps must be taken to manage demand. To this end, and in line with other members of the Southern African Development Community (SADC), Botswana devised a National Water Master Plan (NWMP) and undertook a series of institutional and legal reforms throughout the 1990s so as to make water resources use more equitable, efficient and sustainable. In other words, the stated goal is to work toward Integrated Water Resources Management (IWRM) in both policy and practice. However, policy measures have had limited impact on de facto practice. This paper reflects our efforts to understand the disjuncture between policy and practice. The information presented here combines a review of primary and secondary literatures with key informant interviews. It is our view that a number of constraints—cultural, power political, managerial—combine to hinder efforts toward sustainable forms of water resources use. If IWRM is to be realized in the country, these constraints must be overcome. This, however, is no small task. URI: http://hdl.handle.net/10311/405 Files in this item: 1
Swatuk_PCE_2004.pdf (1.142Mb) -
Gwebu, T.D. (Taylor & Francis (Routledge), http://jir.ucsur.pitt.edu/, NaN, 2008)[more][less]
Abstract: Based on the intergenerational wealth flows conceptual framework, this paper investigates how the AIDS pandemic threatens to disrupt the transfer of resources between generations by using a typical low income urban area in sub-Saharan Africa as a case study. It explores the everyday living conditions of orphans, their guardians, and the primary home caregivers, with the intention of gaining a deeper insight into their current and future life chances, as a result of parental morbidity and mortality due to HIV/AIDS. The research employs a qualitative methodology and relies on documentary information from secondary sources. Short- and long-term recommendations on how to mitigate the negative impacts of HIV/AIDS on wealth transfers among the affected populations are suggested based on the study findings. URI: http://hdl.handle.net/10311/1019 Files in this item: 1
Gwebu_JIR_2008.pdf (1.160Mb) -
Kalabamu, F.T. (Elsevier Science Ltd. http://www.elsevier.com/locate/landusepol, NaN, 2000)[more][less]
Abstract: Since attainment of independence, almost every country in East and Southern Africa has introduced some kind of land reform aimed at reconciling indigenous land tenure practices and those introduced by colonial regimes. The reforms have centred on modi"cation of tenurial rules on access, ownership, administration and transfer of land rights coupled with land redistribution and/or restitution in some countries. With the exception of a few countries, such as Botswana, land reforms have largely remained on statute books with little to show on the ground. The paper gives an overview of land reforms in East and Southern Africa, taking Botswana as a case study. It notes that although Botswana has largely been successful in implementing land reforms, it is currently experiencing land tenure problems, especially in peri-urban settlements and inner city low-income areas, despite government's enhanced control over local land administrative structures. The paper ends with suggestions on how to contain the current problems. URI: http://hdl.handle.net/10311/1134 Files in this item: 1
Kalabamu_LUP_2000.pdf (1.757Mb) -
Gwebu, T.D. (Taylor & Francis Ltd, http://www.tandf.co.uk/journals/cepe, NaN, 2002)[more][less]
Abstract: In sub-Saharan Africa, communal land resource utilization and management has reflected changes in sociocultural belief systems, population dynamics, and modes of societal administration and regulation. This paper, based on archival evidence, attempts to substantiate this assumption through an illustrative case study on biomass depletion around large settlements in Botswana. It also suggests that a revisit to certain traditional institutional and sociocultural practices on natural resource management might provide useful insights towards the sustainable utilization of wood resources. URI: http://hdl.handle.net/10311/959 Files in this item: 1
Gwebu_EPE_2002.pdf (597.0Kb) -
Atlhopheng, J.R.; Ekosse, G. I. E. (Bioline http://www.bioline.org, NaN, 2007)[more][less]
Abstract: A mineralogical investigation of duricrust suites in Letlhakeng valley, and five pans around Jwaneng in Botswana was undertaken in order to know the mineral assemblages and infer on their landscape formation. In Letlhakeng, duricrusts comprised calcretes, silcretes and ferricretes. Calcretes were dominated by the minerals: calcite, quartz and to a lesser extent dolomite. Silcrete mineralogy was dominated by quartz, opal, and some occurrences of palygorskite, microcline and rutile. The intermediate forms of cal-silcretes yielded quartz, muscovite, and kaolinite. Ferricretes occurred on an area of the valley capping, with minerals dominated by goethite and haematite. The indurates are believed to have been formed through groundwater mechanisms. The general lowering of the valley, led to precipitation of the duricrusts. The pans were dominated by calcrete and silcrete only. The calcretes mineralogy was mainly calcite, dolomite and quartz. Illite-montmorillonite and sepiollite were also present. Samples of pan clay floor, other than being dominated by calcite, dolomite and quartz, also had sepiollite ferrian. Pans and valleys are accumulation sites, with polygenetic modes of genesis. The duricrusts have undergone several alterations throughout time. URI: http://hdl.handle.net/10311/679 Files in this item: 1
Atlhopheng_JASEM_2007.pdf (494.4Kb)