Research Publications (Systems Science)
Permanent URI for this collectionhttp://ir-dev.dut.ac.za/handle/10321/842
Browse
Item Indigenous strategies and empirical models for adaptability of the maize-bean intercropping system to climate change(UZ Foundatoin, 2016-12) Mapanda, S.; Chitja, J. M.; Duffy, Kevin JanThis review article discusses on different ways of indigenous strategies and empirical models as an adaptation to climate change by smallholder farmers in Africa. Indigenous adaptation strategies are methods that enable individuals or communities to adjust to the impacts of climate change in local areas. Some of the strategies practiced are: zero tillage, mulching, soil management techniques, organic agriculture and fallow system of cultiva-tion, intercropping with legumes, early planting and use of tolerant varieties to drought, water conservation and crop diversification. Scientists developed many empirical models that are used to project the impact of climate change to agriculture. Some of the empirical models include: CERES-Maize Crop Model, Global Circulation Models (GCM) and histori-cal data records. There is also use of empirical evidence such as indigenous land unit framework, indigenous early warning systems, use of rainmakers, movement of birds, ants and crying of dogs by the indigenous smallholder farmers in Africa. Intercropping system is the best practice used as a strategy to climate change adaptability, and one of the most suitable intercropping systems is that of maize and bean. However, the current research findings revealed that there is a lack of consideration of indigenous knowledge that could enhance livelihoods that depend on natural resources directly affected by climate change.Item Microbiological water quality along Vaal Gamagara’s potable water distribution system(Business Perspectives, 2015) Mokhosi, Agnes; Dzwairo, BloodlessSafe drinking water is essential to all life forms. Thus analysis for microbiological parameters is critical as this assists in declaring the fitness of potable water for human consumption, among other sustainable and “green uses”. The aim of this paper is to investigate the microbiological quality of potable water along Vaal Gamagara Water Treatment Plant’s (VGWTP) distribution system. A total of 10 samples were collected weekly along the system. The samples were col-lected from January to December 2013 in order to analyze for Escherichia coli (E.coli), total coliforms (TC) and Hete-rotrophic plate counts (HPC). The results showed that only 0.1% and 0.4% of samples analyzed were positive for E. coli and total coliforms, respectively. However, HPC results showed that 40% of the samples analyzed from June to December 2013 had higher counts than the recommended standard limit. The chlorine residual showed an increase from June to December 2013. An assessment of the results indicated that the integrity of the system was compromised for the research period. Water quality failures in a distribution system are unacceptable because they threaten human health and sometimes result in loss of life. Thus the assessment called for an urgent need to boost chlorine residual especially at points further away from the treatment plant. This was envisaged to provide a safety net for microbial compliance while the system was critically and continuously monitored, and further investigations were performed. Studies on chlorine decay were recommended as a priority in order to optimize disinfection and maintain good quality drinking water throughout the system.