http://hdl.handle.net/10311/454 2026-07-11T06:37:12Z http://hdl.handle.net/10311/409 Current impact of mining alkaline rocks on Save River water quality in Zimbabwe Meck, M.; Atlhopheng, J.; Masamba, W.R.L. 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 2009-01-01T00:00:00Z http://hdl.handle.net/10311/283 Natural resources accounting: A tool for water resources management in Botswana Hambira, W.L. Natural Resource Accounting (NRA) has become an important environmental/natural resources management tool in recent years. It provides information on stocks of a resource available at a particular point in time and what activities the resource is being used for. The conventional System of National Income Accounts (SNA) normally does not capture the cost of depletion, degradation or pollution of natural resources. This encourages unsustainable use of natural resources since the costs are not reflected when assessing the country’s economic performance or development progress. NRA is thus an attempt to integrate environmental issues into the conventional national accounts. The water sector is one sector that could greatly benefit from this natural resource management tool. Botswana has adopted NRA as a natural resource management tool and has so far developed accounts for minerals, livestock and water. The focus of this paper is on Water Accounting (WA) in relation to Integrated Water Resources Management (IWRM). IWRM is concerned with coordinated development and management of water in order to maximise economic and social welfare without compromising the sustainability of ecosystems. WA helps fill data gaps since it provides the required information for IWRM to be achieved. The aim of this paper therefore is to evaluate the Water Accounts of Botswana Report of 2006 to determine the extent to which it can contribute to integrated water resources management. The paper is based on literature review and the results show that: the available water stocks vary depending on rainfall patterns, well fields are over utilised, there has been growth in consumption, and more than 80% of the waste water produced is not being put to use. These results calls for changes in policies, role of institutions and practices pertaining to water resources management which is what IWRM is all about hence the paper concludes that indeed WA can contribute to the realisation of IWRM. 2007-01-01T00:00:00Z