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Toteng, E.N. (Springer http://www.springerlink.com/index/05CM7XY4DJGUEUQL.pdf, NaN, 2001)[more][less]
Abstract: For the last three and half decades, Botswana has been widely acclaimed to be one of sub-Saharan Africa's longest and most stable liberal democracies, coupled with and sustained by a growing economy. One of the major contradictions, however, within this development scenario, has been the neglect of environmental problems in the country in general, and urban environmental issues in particular. Part of the problem fueling the misconception of environmental issues in Botswana is the state's domination of the country's environmental agenda. This is linked to the power disjunction in decision-making and policy processes between state and nonstate actors over the most appropriate course of action to tackle the problems. Without adopting appropriate analytical frameworks, it is possible that the problem of urban environmental mismanagement in Botswana will persist. This article examines some of the major urban environmental issues in Botswana from neighborhood, citywide, and urban–rural interface perspectives. Further, the elite theory of public policy is used to explain constraints on policy change in the urban environmental management arena in Botswana URI: http://hdl.handle.net/10311/365 Files in this item: 1
Toteng_EM_2001.pdf (933Kb) -
Gwebu, T.D. (Pergamon, www.elsevier.com/locate/habitatint, NaN, 2002)[more][less]
Abstract: In most sub-Sahara African cities, rapid urbanization has placed a heavy burden on available human, financial and socioeconomic resources. The problem has been compounded by the intricate and interactive effects of rapid population growth, the inability of local authorities to handle the increasingly complex functions of metropolitan management, centralization of decision-making by Central Governments, economic structural adjustment programmes, and even unfavourable variations in weather patterns. This is a historical case study, covering the period of roughly from 1989 to 1995. It is based on secondary sources, participation by the author in water supply feasibility investigations for Bulawayo, Zimbabwe, and views expressed in stakeholders’ meetings. It illustrates specifically how civic response has challenged the Central Government of Zimbabwe to review and revise its long-term water provisioning strategy for this municipal authority. URI: http://hdl.handle.net/10311/495 Files in this item: 1
GWEBU2002urbanWaters.pdf (1.681Mb) -
Dikinya, O. (University of Botswana, Faculty of engineering and technology, http://www.ajol.info/index.php/bjt/index, NaN, 2008)[more][less]
Abstract: Characterisation of soil water, in particular water flow dynamics is fundamental in assessing the environmental implications to soil management. Soil water characterisation was assessed by measuring soil water content and soil water potential in a draining profile of sandy and loamy soils. Mercury manometers and Neutron probe meter were connected to a 1.2 m high metal-reinforced container filled with soil samples, to simultaneously measure soil water potential and volumetric water content, respectively. Soil water contents (SWC) were found to decrease monotonically with time, with a rapid decrease in the first 50 hrs of free drainage in both soils. Sandy soil was more prone to huge losses of water than loamy soil attributed to numerous large drainable pores in sandy soil. An appreciable difference of SWC in the upper layer (SWC= 0.22 cm3/cm3) and the bottom layer (SWC= 0.35 cm3/cm3), in the case of loamy soil was attributable to its poor drainage properties. URI: http://hdl.handle.net/10311/1006 Files in this item: 1
Dikinya_BJT_2008.pdf (116.4Kb) -
Dikinya, O.; Lehmann, P.; Hinz, C.; Aylmore, G. (Wiley http://www.interscience.doi.wiley.com/10.1002/hyp.6299, NaN, 2008)[more][less]
Abstract: A pore-scale model based on measured particle size distributions has been used to quantify the changes in pore space geometry of packed soil columns resulting from a dilution in electrolyte concentration from 500 to 1 mmol l 1 NaCl during leaching. This was applied to examine the effects of particle release and re-deposition on pore structure and hydraulic properties. Two different soils, an agricultural soil and a mining residue, were investigated with respect to the change in hydraulic properties. The mining residue was much more affected by this process with the water saturated hydraulic conductivity decreasing to 0Ð4% of the initial value and the air-entry value changing from 20 to 50 cm. For agricultural soil, there was little detectable shift in the water retention curve but the saturated hydraulic conductivity decreased to 8Ð5% of the initial value. This was attributed to localized pore clogging (similar to a surface seal) affecting hydraulic conductivity, but not the microscopically measured pore-size distribution or water retention. We modelled the soil structure at the pore scale to explain the different responses of the two soils to the experimental conditions. The size of the pores was determined as a function of deposited clay particles. The modal pore size of the agricultural soil as indicated by the constant water retention curve was 45 μm and was not affected by the leaching process. In the case of the mining residue, the mode changed from 75 to 45 μm. This reduction of pore size corresponds to an increase of capillary forces that is related to the measured shift of the water retention curve. URI: http://hdl.handle.net/10311/490 Files in this item: 1
Dikinya_HP_2008.pdf (1.769Mb) -
Chipanshi, A.C.; Chanda, R.; Totolo, O. (Springer http://www.springerlink.com/content/p88867543584713, NaN, 2004)[more][less]
Abstract: This study examines the sensitivity of maize and sorghum crops to global warming in Botswana, a country with arid climatic conditions and shortfalls in locally produced grain. The vulnerability of the maize and sorghum crops to climate change were studied using crop simulation models while climate change scenarios were generated from Global Circulation Models. Simulated yields indicated that rain-fed crop production under the observed climate was a small fraction of what could be produced under optimal conditions. The gap was attributed to both physical (especially lack of rain) and socio-economic constraints. Using the southern African core climate change scenario, simulated yields declined by 36% in the case of maize and 31% for sorghum in the sand veldt region. Yield reductions from the hard veldt region were in the order of 10% for both maize and sorghum. The growing season became shorter, the average reduction in days in the sand veldt region being 5 and 8 days for maize and sorghum respectively, and correspondingly, 3 and 4 days over the hard veldt region. The food security option currently followed in Botswana was found to be a good adaptive strategy under a changed climate. URI: http://hdl.handle.net/10311/412 Files in this item: 1
chipanshi_CC_2003.pdf (1.144Mb) -
Masike, S.; Urich, P. (Academic journals http://hdl/handle.net/10289/973, NaN, 2008)[more][less]
Abstract: Cattle’s rearing in Botswana is undertaken in two sectors: the communal and commercial. The communal sector is exclusively free range and therefore depends on biomass production. This makes the systems highly susceptible to drought. One strategy that has been devised by farmers to adapt to drought has been to overstock. However, this strategy may not be the best adaptation strategy as it leads to overgrazing and quick depletion of scarce biomass during the drought years. Climate change may increase the vulnerability of the communal cattle sector in the country mostly through changes and variability of rainfall. In the article, we determine the reliability of the rainfall in the Khurutshe area, Botswana. Vulnerability of the cattle sector to system severe failure is also determined. Lastly, the effects of climate change on return period of drought are investigated. Results indicate that the reliability index of rainfall in the Kgatleng District is 0.5. The vulnerability index of the cattle is estimated at 8000 per year. Lastly, using SimCLIM computer model climate change will shorten the return period of mild drought from 2 years to 1.6 years by 2050. These findings have serious implications on the recovery period of the cattle to withstand the next drought period. URI: http://hdl.handle.net/10311/542 Files in this item: 1
Masike_JGRP_2008.pdf (555.0Kb) -
Mbaiwa, J.E. (Elsevier http://www.doi:10.1016/j.jenvman.2005.03.007, NaN, 2005)[more][less]
Abstract: This paper uses the concept of sustainable development to examine the utilisation of wildlife resources at Moremi Game Reserve (MGR) and Khwai community area (NG 18/19) in the Okavango Delta, Botswana. Using both secondary and primary data sources, results show that the establishment of MGR in 1963 led to the displacement of Khwai residents from their land; affected Basarwa’s hunting and gathering economy; marked the beginning of resource conflicts between Khwai residents and wildlife managers; and, led to the development of negative attitudes of Khwai residents towards wildlife conservation. Since the late 1980s, a predominately foreign owned tourism industry developed in and around MGR, however, Khwai residents derive insignificant benefits from it and hence resource conflicts increased. In an attempt to address problems of resource conflicts and promote sustainable wildlife utilisation, the Botswana Government adopted the Community-Based Natural Resource Management (CBNRM) programme, which started operating at Khwai village in 2000. The CBNRM programme promotes local participation in natural resource management and rural development through tourism. It is beginning to have benefits to Khwai residents such as income generation, employment opportunities and local participation in wildlife management. These benefits from CBNRM are thus having an impact in the development of positive attitudes of Khwai residents towards wildlife conservation and tourism development. This paper argues that if extended to MGR, CBNRM has the potential of minimising wildlife conflicts between Khwai residents and the wildlife-tourism sectors. This approach may in the process promote the sustainable wildlife use in and around MGR. URI: http://hdl.handle.net/10311/439 Files in this item: 1
Mbaiwa_JEM_2005.pdf (2.041Mb)
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