Ndwamato, Ramabulana Cassius2024-01-262024-01-262024Hadebe, Nomsombuluko Dayanda Elizabeth. (2022). Influence of copper on the corrosion and mechanical properties of Grade 4 titanium for biomedical applications. [Master's dissertation, University of the Witwatersrand, Johannesburg]. https://hdl.handle.net/10539/37439https://hdl.handle.net/10539/37439A research report submitted in partial fulfilment of the requirements for the degree Master of Science to the Faculty of Science, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, 2023The sugar business in South Africa has a strong socioeconomic development focus in rural regions, creating jobs, giving a source of revenue, and constructing transportation and communication networks. Despite its benefits, the sugar sector has faced several obstacles mostly by Small-Scale Growers (SSGs), which have led to a decline in sugarcane production. This study analysed borehole water properties such as electrical conductivity, water levels, and temperature at the Makhathini Irrigation Scheme in KwaZulu-Natal. The quality of water from the Jozini/Pongola Dam used for irrigation was also analysed, in addition to the salinity levels of the soil at the irrigation scheme. Water from nineteen (19) boreholes within the irrigation scheme between 2016 and 2020 was collected every three months from January and tested. Annual water quality data collected upstream (PR1) and downstream (PR2) of the dam were obtained from the Department of Water and Sanitation. One kilogram of soil was collected from six sampling points, respectively, within the Makhathini Irrigation Scheme and sent for testing at the Agricultural Research Council Institute of Soil Water and Climate. Rainfall data and annual sugarcane yield data were obtained and analysed. The ANOVA results showed a significant (p < 0.05) difference in electrical conductivity (EC) between all 19 boreholes in the five-year data. The Tukey test also confirmed the electrical conductivity’s significant (p < 0.05) variation across all boreholes during dry and wet seasons. The borehole water level analysis shows that no significant (p > 0.05) difference was observed in dry seasons, but there was a significant difference in the wet seasons. The Tukey test also confirmed that the borehole water levels varied significantly during the wet season for the five-year study period, suggesting that the water levels were shallow in the wet seasons compared to the dry season. The borehole water temperature analysis indicates no significant (p > 0.05) difference for all seasons from 2016 to 2020. The water collected at PR1 suggests that the water from the dam is of acceptable quality for irrigation, while the return flow to the Pongola River at sampling point PR2 had high SAR, EC, and PO4 - concentrations. Samples collected downstream (PR2) show signs of pollution. This suggests that water contamination occurs when water passes through the Makhathini Irrigation Scheme. A t-test analysis reveals that pH, NO3 - , and NO2 have no significant (p > 0.05) difference, but SAR, EC and PO4 - were significant (p < 0.05). The measured parameters were compared to the Department of Water Affairs and Forestry standards for the quality of water used in agricultural irrigation. The correlation analysis between rainfall, borehole electrical conductivity, borehole water levels, and sugarcane yields revealed that while rainfall influenced borehole electrical conductivity, water levels, and sugarcane yield, the effect was minimal, possibly due to irrigation volumes. Rainfall had a positive effect on sugarcane production and EC but a negative effect on water levels. Soil salinity analysis demonstrated an increase in the soil's electrical conductivity with each passing year. The ANOVA analyses for sugarcane yield and soil salinity reveal statistically significant differences (p < 0.05). The accumulation of salts in the soil at the Makhathini Irrigation Scheme, also seen by the contaminated return flow to the Pongola River, reduces sugarcane yields. Water properties of the sugarcane irrigation water affect the soil salinity in the irrigation scheme and, consequently, the decline in sugarcane production by small-scale growers.en©2024 University of the Witwatersrand, Johannesburg. All rights reserved. The copyright in this work vests in the University of the Witwatersrand, Johannesburg. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of University of the Witwatersrand, Johannesburg.WaterloggingIrrigation water qualitySugarcaneSDG-6: Clean water and sanitationDissertationUniversity of the Witwatersrand, Johannesburg