Environmental impact of household solid waste disposal practices on plant growth in rural areas of KwaZulu-Natal : a case study of uThukela District Municipality

Abstract

The absence or unavailability of solid waste disposal facilities and service in rural areas of the UThukela District Municipality (UTDM) compelled residents to adopt many disposal practices. This included open burning of waste, which leaves residues in the form of waste ashes. Some heavy metal and hazardous substances remain active in these waste ashes. In this study, the impact of Solid Waste Disposal Practices (SWDP) on the environment was investigated by evaluating the effect of waste ashes on plant growth. The research was directed towards the evaluation of the environmental impact of solid waste disposal practices by households in these rural areas of KwaZulu-Natal (South Africa), on the growth of Zea Mays (Maize) plants. Rural maize farmers dominate the district of UTDM because it is a good agricultural area with great potential for high rainfall in summer, moderate temperatures, good soil and moderate slopes. The method selected to achieve research objectives was the evaluation of the influence of waste ashes, as by-products of SWDP, on plant growth. This was achieved by, determining soil fertility; collecting household solid waste from different rural families to determine the composition (including already burnt ash, plastic ash and wood ash; analysing the chemical composition of traditional ashes collected from sites where it was burnt (waste ashes); applying the evaporation pan test; mixing waste ashes and other additives with soil in planting pots in equal parts; planting Zea Mays in winter and summer; and lastly, monitoring and measuring agronomic parameters of plant growth on a regular basis. The selected additives to the in situ soil were fertilizer, compost, waste ash, plastic ash and wood ash. Pots with soil only (no additive added) served as control. The findings revealed that plants exposed to wood, waste and plastic ash struggled to grow when compared to plants grown with fertilizer, compost and soil only. The impact of all waste ashes on plant growth was negative in both seasons and some of the agronomic parameters were unable to sprout during the course of plant growth. The chemicals found after analysing the waste ashes included some of the heavy metals that remained active after burning. These were left behind in the environment. Consequently, it was concluded that household solid waste disposal practices in rural areas should be reviewed urgently, as they affect plant growth negatively. Recommendations were provided.