Biogeosciences News

Does War Influence Forest Growth?

Research focused in South Sudan shows that armed conflict can have a subtle effect on regional ecology.


Over the past half century, wars in Sudan and what is now South Sudan killed more than 2 million people and displaced more than 4 million more. Although the human cost is the most tragic outcome of armed conflict, a 17 December presentation at AGU’s 2014 Fall Meeting in San Francisco, Calif., explored another facet of war: its effects on the environment.

The ecological aftereffects of war are far from straightforward. On the one hand, less governance can lead to an increase in banned practices like poaching and harvesting of protected natural resources. On the other hand, a lack of oversight can reduce destructive government-sponsored practices like mining and deforestation. In the demilitarized zone between North and South Korea, for instance, biodiversity has skyrocketed ever since human activity was banned there in 1953. Because a huge number of conflicts occur in biodiversity hot spots—80% of all conflicts from 1950 to 2000, according to one study—it is vital to understand how ongoing strife will affect the surrounding environment.

A Close Look at South Sudan from Space

For a case study, geographer Virginia Gorsevski from the Global Environment Facility turned to South Sudan, where satellites have imaged terrain during and after war. Her objectives were twofold: to determine the effects of conflict on the country’s forests and to evaluate the utility of data gathering using satellites.

A comparison of forest loss and gain during (left) and after (right) wartime. Image from Virginia Gorsevski.
A comparison of forest loss and gain during (left) and after (right) wartime. Image from Virginia Gorsevski.

“I was really interested in looking at how remote sensing could be used in these areas which are otherwise inaccessible,” she said. “It makes remote sensing an ideal technology to use to access this information.”

Gorsevski and her colleagues hypothesized that ongoing conflict led to increased tree growth in South Sudan. By their estimation, most residents would have fled to refugee camps, allowing vegetation to grow unhindered in villages and on agricultural land.

The team estimated forest cover in the county using algorithms designed to identify vegetation in satellite imagery. They calculated the changes in forest cover during wartime (1980s to 2001) and in the period at the end of the war leading up to South Sudan’s independence (2003–2010).

Trends in the extent of forests during the 30-year study period were subtle, resulting in a small net gain in the country’s forests, as the researchers had expected. However, some places still surprised the researchers—such as a forested area damaged both during and after the war because, as Gorsevski noted, the Sudan People’s Liberation Army permitted its unrestricted deforestation.

Surveying People Affected by War

To figure out why the effects were so slight, the researchers supplemented their data with surveys of people in South Sudan. Gorsevski interviewed locals using a strategy called participatory mapping. “I took some of the satellite imagery with me and I handed it out to a focus group,” she said. “I asked them to point out where did they go during the war, what did they do?”

Villagers, guides, and local lawmakers revealed hidden trends in how people relocated. For instance, after the war ended, many refugees remained in camps for their schools and hospitals, preventing rapid postwar redevelopment in village areas. Although the information gathered on the ground was predominantly qualitative, it helped to illuminate patterns the researchers could not have gleaned from satellite data alone.

Toward New Perspectives on Armed Conflict

This union of data and personal interaction was one reason NASA researcher Jamon Van Den Hoek invited Gorsevski to present her team’s research at an oral session on armed conflict and environmental change. Conflict study is decades old, he says, but environmental scientists are poised to offer new perspectives on the field.

“I think there’s a great opportunity to really fuse the kinds of data we have…with broader theoretical frameworks that are very mature and very developed,” Van Den Hoek said.

—Kerry Klein, Freelance Writer

Citation: Klein, K. (2014), Do wartime movements influence forest growth?, Eos, 95, doi:10.1029/EO020949.

© 2014. The authors. CC BY-NC 3.0