Stratification regimes and thermodynamic modelling of a subtropical African reservoir

The stratification of a lentic water system is an important factor regulating its biotic activities and processes. The present study investigated changes in temperature and oxygen stratification regimes in Mazvikadei Reservoir 27 years after the first study was conducted during its filling phase. The FLake‐Global model was also tested as a predictive tool for the first time to analyse annual limnological trends in a subtropical reservoir. The lake‐modelling tool FLake‐Global enables an instantaneous estimation of the seasonal cycle of temperature and mixing conditions in shallow freshwater lakes around the world. The results of the present study illustrate that the reservoir was weakly stratified, with the overall thermal stratification patterns somewhat similar to those recorded during the filling phase (1992). The oxygen stratification patterns observed in the present study correspond well to those of thermal stratification. The depth‐integrated oxygen profiles for both the deep and shallow sampling sites exhibited the same pattern, with higher concentrations from July to September. The water column was well oxygenated, indicating the reservoir has matured since its filling phase in 1992, when there was significant hypolimnetic deoxygenation. The FLake‐Global model exhibited good results in predicting annual trends, with the results also indicating no differences in stratification levels in the reservoir for the current and Masundire (1992) filling phase studies. The model predicted lower surface and bottom temperatures, however, compared to those measured in the reservoir. There was lowering of the mixed layer depth from the hot‐wet (November–April) months through the cool‐dry (May–August) season. Latent heat fluxes agreed with the net longwave (LW) predictions for Mazvikadei Reservoir, which exhibited an overall net cooling effect. The stratification has not changed significantly since the previous study in 1988. The FLake‐Global model proved a useful predictive tool when tested in a subtropical system.     

The influence of green marketing strategies on business performance and corporate image in the retail sector

Green marketing strategies are employed by many enterprises to enhance their corporate image and business performance. Green marketing is perceived as the commitment of a business or an organisation towards the development of safe, eco‐friendly goods and services by employing recyclable and easily decomposed packaging, better pollution prevention methods, and a more efficient use of energy. Against this background, the study followed a case study approach using South Africa's retail giants, Woolworths and Pick n Pay. Stratified purposive sampling was used to carry out in‐depth interviews and administer questionnaires with senior management of the selected retailers. In addition, document and website analyses were used for triangulation purposes. Path analysis and content analysis were used to establish the correlation. The study established that green marketing strategy has a positive effect on corporate image and on business performance. The paper recommends that if enterprises are to sustain competitive advantage, particularly in the retail sector, it is in their best interest to adopt green marketing strategies.