Driving past Theewaterskloof Dam, sand and dust swirl in the air at huge heights. The dam is continually adapted to keep water flowing and there is now visible evidence that areas of the dam are unable to recover from the ongoing drought. The swirling dust indicates a significant change in the ecosystem that, while on a smaller scale, mirrors a natural phenomenon elsewhere: sand storms.
Sand storms date back 70 million years, however it is only in the last few decades that they have sparked curiosity and triggered deeper study.
The Sahara Desert, stretching across the northern third of Africa, is the world’s most important origin of sand storms. Every year, between November and March, the Harmattan wind carries around 182 million tons of sand and dust on a transcontinental journey over the Atlantic and Mediterranean Oceans to Europe and South America. Throughout its journey, the dust fertilizes both aquatic and terrestrial ecosystems and it is a vital supply of nutrients to the Amazon Rain Forest.
The sand comes from two main regions in the Sahara Desert: the Tibesti Mountain Region and the Bodele Depression in Chad, once a majestic lake named Mega Chad but now a barren lake bed. The sand from the Sahara and dust particles from rock erosion contain rich minerals composed of dead microorganisms filled with phosphorus. This nutrient is essential for plant proteins and the growth in forests, such as The Amazon, where it replaces nutrients flushed away by rainfall.
The sand also settles in the ocean, contributing to the health of marine life and the ocean floor.
Does the importance of the Saharan sand storms also apply to the dust clouds kicked up from Theewaterskloof Dam? What impact do the sand storms have on the surrounding area? What implication does it have for nearby residents, agriculture, and animal and plant life?
The sand storms of the Theewaterskloof Dam are obviously far smaller than those of The Sahara Desert, but the same principles apply. How is the ecosystem in Theewaterskloof adapting to the changes and what will the long-term effects be?
Check out the below links to find out more about the Sahara sand storms and their impact on Africa and the world: