An ISU professor’s work on soil erosion in Africa may have beneficial effects throughout the world.

Andrew Manu, associate professor of agronomy, has been working to prevent the loss of soil material and the formation of deep gullies in West Africa.

Manu’s work on erosion control methods is being used to restore the Sahel, the region just south of the Sahara Desert, and Niger River in West Africa.

“His work in Niger also illustrates the global perspective of the agronomy department,” said Melea Reicks Licht, communication specialist for agronomy.

“It will not only aid those in Africa, but the knowledge gained through his project will benefit other soil scientists throughout the globe.”

Manu said because of the Sahel’s closeness to the Sahara, its soil is very sandy and easily eroded.

Runoff has caused large amounts of soil to be deposited in the Niger River, he said, creating alluvial fans — fan-shaped deposits of water-transported material.

“The bad part is this soil is deposited to form alluvial fans, which are unproductive,” Manu said.

Rainfall causes the soil to be swept away and then deposited in the rivers, he said. Eventually, if nothing is done to prevent soil from being deposited in rivers, a bridge of sediment could be formed.

“I could be like Jesus and walk on the water if nothing is done to prevent this,” he said.

Manu and other researchers have devised prevention methods. They have created microcatchments, which are half-moon shaped trenches that are built up with soil, Manu said.

Microcatchments catch and slow down water and sediment, he said.

The material that is deposited in the stopped water can be used to help grow trees in barren areas, he said.

Trees and other structures that are being placed in the area also perform ecological and hydration functions, Manu said.

“They slow down runoff and material and nutrients are caught for tree growth,” Manu said. “The trees protect the soil from the impact of raindrops, which decrease erosion.”

Manu’s research is promoting environmental change through the growth of plants and grasses in the area. This growth has many benefits, including use for livestock feed, firewood and lumber. Starvation could also decrease as livestock are better fed by these grasses, Manu said.

Africa has benefited greatly by Manu’s research, but it could also benefit the rest of the world.

“The impact of this method is devised for the world’s community. We are protecting the world environment,” Manu said.

Erosion is a problem everywhere, including Iowa, Manu said, but his techniques cannot be used in Iowa because the state is too humid.

“This will benefit Iowa in an indirect way because we are all connected,” Manue said. “The impact on humans and the environment will benefit the whole world.”

Manu said he first became involved in erosion prevention in Niger while working as a soil chemist in the area. After going into the field to collect soil samples, he realized there were too many problems to be solved in just a lab.

Licht said research like Manu’s shows how agronomy research can improve the relationship between people and the environment.