Silt loads in the Olifants and Sabie river systems inside the Kruger National Park, were monitored by collecting water samples every consecutive week for a period of 20 months. The variation in silt concentration, changes in selected physico-chemical water quality variables and fish mortalities during flushing (i.e. release of silt, by sluicing) of the Phalaborwa Barrage, were also monitored. The Olifants River inside the Kruger National Park carried high silt loads in summer; in the dry season the suspensoid load was greatly reduced. A similar pattern was observed in the Sabie River, but the silt loads were generally lower. It was apparent that silt loads released from the Phalaborwa Barrage led to large variations in the natural silt loads of the Olifants River. These increased amounts of silt (25 000 mg/1 to >70 000 mg/1) caused drastic reductions in the dissolved oxygen concentration of the water, ranging from >6 mg/1 to 0 mg/1. Depending on the severity and duration of the flushing, fish succumb to such silt loads. These findings, as well as published information, indicate that the management strategy of flushing to improve storage capacity is ecological unacceptable. It is therefore suggested that the use of the Phalaborwa Barrage as a future reservoir should be critically re-evaluated.

Inadequate supply of healthy food impacts negatively on household food consumption and consumers' well-being. Disproportionate income distribution in South African households results in several households that lack daily consumption of adequate healthy foods and reliance on low-cost staple foods. Households are confronted by various challenges, and reliance on highly processed staple foods is a public health concern. This study aimed to gain an understanding of the challenges and needs experienced by households with different food security statuses. A convergent mixed methods design was employed to collect data from income-earning households. The first quantitative phase obtained data on aspects of household food security employing interviewer-administered questionnaires while the face-to-face qualitative phase aimed to gain a better understanding of the challenges participants experience with food choices. The ethical aspects followed throughout the study ensured the continued safety of participants as well as the integrity of accumulated data. Households had experienced insufficient food supply to such an extent that the household was at risk of becoming food insecure or actually insecure among medium and high-income groups. Food insecure households indicated a significantly higher consumption of food, which they do not necessarily prefer, limited portion sizes and they borrowed money to purchase food. Households in the middle-income group applied this coping behaviour. It is thus clear that income alone is not enough to ensure food security. Participants indicated a need for budgeting and basic food knowledge. Promoting self-production, skills and knowledge regarding basic food needs may play a significant role to support households' food consumption and improve household food security. Future developments must aim at sustainable intervention programmes to support household food utilization and management to enhance consumers' well-being through education.

Trend surface analysis is employed to construct statistically significant trend maps of the areal variation in average grain size, sorting coefficient and roundness values of aeolian sand particles from the Namib sand sea, the Richtersveld and the Sandveld. All three parameters indicate that the sand is transported north in the Sandveld, west in the Richtersveld, and northeast in the Namib sand sea. This movement probably constitutes another minor source of Namib sand.

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