Mpambira Kambewa is watching Malawi grow rapidly.
“There is massive urbanization, whereby the cities that are there, you know, are expanding in both size and then also in terms of the social economic activities that happen within the cities,” said Kambewa. “Also, much of the rural areas are also undergoing their own sort of urbanization.”
According to UN Habitat, the east African country is “one of the fastest urbanizing countries in the world with an annual urban growth rate higher than five percent.”
As cities grow in size and population, the amount and kind of waste produced has increased and changed.
Part of Kambewa’s job as community development specialist for the U. S. Forest Service International Program in Malawi is working with communities to find ways to properly manage waste.
“I can help engage the communities that I work with in managing the waste, some of which they've been used to, some of which are more traditional in the sense, but most of which are new because of the massive urbanization,” said Kambewa.
With that goal in mind, Kambewa traveled more than 8,400 miles from Malawi to the U.S. Forest Service Northern Research Station in Rhinelander to learn an additional tool to help.
International Phyto Academy
This is the second year the Northern Research Station has hosted the International Phyto Academy, a week-long hands-on class that teaches Forest Service partners around the world and the U.S. how to use plants to help manage waste that range from landfills to mine sites.
“Phytoremediation has been around for decades, late 80s/early 90s. It kind of became known as a bonafide science, but really for all of humanity, people have been using plants and trees to clean contaminated environments,” said Ron Zalesny, the supervisory research plant geneticist at the Northern Research Station.
He and his colleagues have refined a specific method called phyto-recurrent selection, which was endorsed by the United Nations as a good practice in 2023.
“It is adaptable enough so that folks from around the world can use phyto-recurrent selection to choose what species of trees and perhaps what varieties of trees to use for their particular projects,” said Zalesny.
Zalesny said it involves looking for trees that have extensive roots systems, grow fast, and have the ability to control the amount of water they use.
This Phyto Academy is a way for Zalesny and the Forest Service to teach people this method with the goal of them being able to implement it back home.
Liz Rogers is a Forest Service Pathways Intern and PhD candidate at the University of Missouri. She’s been working with Zalesny since 2016 on various phytoremediation projects and is helping teach the Phyto Academy.
Rogers says while there’s been published peer-reviewed manuscripts on these methods, that can’t replace the hands-on experience people are getting through this course.
“It reaches the scientific community, but it's not reaching practitioners in the way that it could be. Events like this, training academies, in which we have people come in and we give them hands on experience, we bring them to our phytoremediation field sites. It's totally different being in the field, being able to do the techniques hands on, versus reading about it in a paper or in a textbook,” said Rogers.
On the last full day of the academy, the participants are in the Northern Research Station lab handling hybrid poplar and hybrid willow trees that the Forest Service has found work well for phytoremediation.
Everyone gets their own set of seedlings to measure, count roots and leaves, and measure the SPAD, or the greenness of the leaves.
“This process that people are being exposed to, that are getting experience with it on the ground, hands on right now, is a process that was developed back in 2003 by Ron Zalesny and his team at the time, in order to select from these hundreds of varieties of trees, which ones are the best for cleaning up contaminated environments,” said Rogers as she explained each of the stations people were working at.
Bringing phytoremediation home
This is Semenyo Nyakokpa’s second time coming to the International Phyto Academy.
He’s from Togo and works for the U.S. Forest Service International Program in the Democratic Republic of the Congo in west Africa.
Nyakokpa wants to use phytoremediation to help clean up mining waste that has created human health concerns and ecological issues.
“Congo is one of the countries in the world where there are many resources underground,” said Nyakokpa.
He said after the first Phyto Academy, he struggled to find the resources and tools to implement the techniques like the Forest Service does in the U.S.
This second time around has made him realize he doesn’t necessarily need all the scientific tools to get started and make an impact.
“Now I can imagine, when I'm going back in my nursery, I can start implementing propagating sapling that have abilities to phytoremediate some pollutant, especially copper and also sulfate mercury as a contaminant from the soil,” said Nyakokpa.
Both Nyakokpa and Kambewa believe phytoremediation will be a great tool to be used in conjunction with the other work their doing to help communities in DRC and Malawi to manage waste.
“I've been getting skills and techniques, very practical, very practical delivery of the program, and definitely things that are going to stick with me,” said Kambewa.
Zalesny stresses that’s an important factor in this work, phytoremediation is often not the only solution to pollution.
“It might not be the be all, end all, but it's a vital component in how we can solve environmental challenges, and so it's a very good complement to traditional approaches. But why phytoremediation is so valued is because it's a nature-based solution, so it's very sustainable,” said Zalesny.
Zalesny says phytoremediation also tends to be more cost-effective compared to traditional approaches to cleaning waste.
Last year, eight people from four countries participated in the International Phyto Academy in Rhinelander.
Zalesny says participants have already been able to start implementing their phytoremediation projects.
“One success story from last year is a collaborator that we have from the Lebanon Reforestation Initiative. The academy took place in mid-August and by early October last year he had planted over 3,000 trees at a landfill in Lebanon,” said Zalesny. “That was just amazing to us, that he learned enough during that week to go and actually install a phytoremediation application.”
As much as Zalensy and his Forest Service colleagues are able to teach people during the International Phyto Academy, they all say the knowledge is an exchange.
Liza Paqueo is an urban ecologist with the U.S. Forest Service International Program who helped organize the academy.
“We learn from other people, so while we're bringing them over here, just being and creating a network of colleagues from around the world exposes us to the challenges and potential solutions that we don't have the majority of share in,” said Paqueo.
This year, 13 people from six different countries participated in the International Phyto Academy.
Zalesny hopes to see the program continue to grow.
“No matter where you are in the world, people have challenges in their local communities with pollution. That is pollution of the air, the soil, and the water,” said Zalesny. “This occurs both in rural areas and in cities and major metropolitan areas. It makes phytoremediation very applicable no matter where you are in the world.”
