Abstract
Erosion rates on mine slopes and seed establishment of C.ciliaris grass at Otjikoto mine, Namibia.
The Otjikoto mine is located in the central area of Namibia. The mine has huge waste rock dumps that need to be covered with top soil as part of the rehabilitation process. The top soil on the mine is limited and needs to be used sparingly. The study focuses on top soil studies both in a greenhouse, under controlled conditions, and field trials. In the greenhouse experiment top soils dumped in the years 2012, 2013, 2014 and 2016 were collected. The nutrient contents were tested using ICP-MS machine. Cenchrus ciliaris grass was planted in the different top soils to test germination. In the natural environment the different top soils were laid on waste rock at different slope angles of 18º, 25º and 30º. C.ciliaris seeds were planted. This was to test erosion rate on the slopes and seed establishment. In the greenhouse the older top soils from 2012 and 2013 had 50% higher C. cilliaris germination as compared to the later soils of 2014 and 2016. In the natural environment the seeds planted on the 18º and 25º slope showed good germination and survival with minimal soil erosion during the rainy season as compared to the 30 degree slope.
Erosion rates on mine slopes and seed establishment of C.ciliaris grass at Otjikoto mine, Namibia.
The Otjikoto mine is located in the central area of Namibia. The mine has huge waste rock dumps that need to be covered with top soil as part of the rehabilitation process. The top soil on the mine is limited and needs to be used sparingly. The study focuses on top soil studies both in a greenhouse, under controlled conditions, and field trials. In the greenhouse experiment top soils dumped in the years 2012, 2013, 2014 and 2016 were collected. The nutrient contents were tested using ICP-MS machine. Cenchrus ciliaris grass was planted in the different top soils to test germination. In the natural environment the different top soils were laid on waste rock at different slope angles of 18º, 25º and 30º. C.ciliaris seeds were planted. This was to test erosion rate on the slopes and seed establishment. In the greenhouse the older top soils from 2012 and 2013 had 50% higher C. cilliaris germination as compared to the later soils of 2014 and 2016. In the natural environment the seeds planted on the 18º and 25º slope showed good germination and survival with minimal soil erosion during the rainy season as compared to the 30 degree slope.