Mulele Nabuyanda earns PhD for research on the impact of minerals in Zambian wetlands
Mulele Nabuyanda from Zambia has been awarded a PhD. On 15 April, he successfully defended his PhD thesis entitled: ‘’Investigating cobalt, copper, and lead in sediments and phragmites mauritianus and Typha spp. in three Zambian wetlands. Professor Kenneth Irvine was his promotor and Dr. Peter Kelderman was his co-promotor.
Assessing the impact of minerals
My research was born out of my involvement in environmental work in Zambia. Little research has been done on the environmental impact of mining activities. I researched how much mining activities are polluting wetlands and how these minerals effect plants such as phragmites. The greenhouse study investigated how trace metals in the mining wastewater are attenuated by the wetlands. This involved assessing whether trace metals flow through or are deposited into the sediments and whether they are retained by plants.
The research also investigated the distribution of the trace metals in plant parts and whether the plants can be used to manage pollution in our wetlands. For certain plants it is possible to remove pollution from sediments or to stabilize the sediments so they do not release bound trace metals. Experiments in a greenhouse in Delft showed that wetlands are very effective in removing trace metals from the water column and sequestrating them in the sediments. They also showed that wetland plants take up trace metals from sediments.
Greenhouse and onsite studies
I was very fortunate because my studies enabled me to study in the greenhouses in the Netherlands and at three wetlands in Zambia. The academic board allowed me to take hundreds of samples from the field to analyse. This was very helpful for my study, but it was hard work. It took me more than six years to complete due to the complexity of my research. Nevertheless, I made a lot of friends in the laboratory and we had great fun and the time I spent writing papers has been very valuable.
Long working hours
My working hours were so long that my friends joked that I was doing three PhDs at the same time. I had a lot on my hands! The laboratory work was challenging. The chemical analyses were very complex and getting good results was a long process. It is not as simple as administering a questionnaire. I had to try many different methods and apply them throughout all the samples. During the laboratory work, when equipment stopped working, it had to be ordered from abroad which seemed to take a painfully long time.
Mitigate pollution of trace metals from wastewater
My PhD research could be very useful when trying to mitigate the effects of pollution by trace metals from wastewater in wetlands. It shows that we do not need to drain or dredge the wetlands to treat pollution. My work could potentially help form legislation to monitor the exposure of sediments to trace metals, the role of plants and what is going on in the wetlands. In the Netherlands, this legislation already exists, but Zambia still has a lot of work to do.
Advice to myself
I would say don’t be overambitious. I had a lot on my hands, but I am proud of what I achieved because I made a fully comprehensive and informative study of what is going on in the wetlands.
Related
News ·
Sebrian Beselly earns PhD for research that can help mangrove restoration succeed
On 12 July, Sebrian Beselly from Indonesia defended his PhD thesis on simulating mangrove forest growth and expansion. He presented a method to model mangrove forests’ trajectory and wetland development, which eventually can make mangrove restoration projects more likely to succeed. His promotor is Professor Dano Roelvink and his co-promotor Associate Professor Mick van der Wegen. Dr. Sebrian Beselly, who was awarded a doctoral degree for his research, shared a few insights as he embarks on a new chapter of his life.
News ·
Graduation: MSc Limnology and Wetland Management students are awarded degrees
After almost two years of intensive studies and research in Austria, Kenya and the Netherlands, a group of students were awarded their degrees last week – proof of their new knowledge and skills in limnology and wetland management.
News ·
IHE Delft project creates web application to assess nature-based solutions for climate adaptation
Choosing the right nature-based solutions for climate adaptation is tricky. Will measures such as blocking ditches, restoring wetlands or creating infiltration ponds give the best results? Or is tree planting or heathland restoration better? Or other measures, or a combination? A new application, developed by IHE Delft, in collaboration with Open University and the Province of Noord Brabant, helps decision-makers in the Dutch-Belgian Aa or Weerijs river catchment evaluate solutions.