News / Africa

Fighting Fire with Fire

African savannah wildfire  (Credit: World Agroforesrtry Center)
African savannah wildfire (Credit: World Agroforesrtry Center)


Joe DeCapua
In African savannahs, or grasslands, wildfires can either be destructive or beneficial. It all depends on when those fires occur. Scientists at the World Agroforestry Center have developed a system to determine the best time to set the savannahs ablaze.

Savannahs stretch across many parts of Africa. But scientists concentrated their research on grassland conditions similar to the Sahel and South Sudan. When wildfires spread uncontrolled, the heat and flames can cause damage on several levels.

“Many components of the ecosystem can be affected. The biodiversity itself, the soil composition and structure and gas emission and greenhouse gas emission into the atmosphere,” said Cheikh Mbow, senior climate change scientist with the World Agroforestry Center in Nairobi, Kenya.

“Fire is seen as one of the biggest drivers of deforestation in some ecosystems. And it contributes widely to the reduction of the ecosystem services, which [are] the basis of most of the livelihoods in Africa in poverty conditions. So we are worrying about fire because of the many impacts and implications for the human beings.”

Fires in savannahs are common.

“If you look at African images from [a] satellite in the dry season, it appears that most of the ecosystem, which has some level of dryness, will have fires on a regular basis. There have been many attempts in the past, since colonial time actually, to, sort of, ban fire in our ecosystem, but they never succeeded. They never succeeded because fire is a tool,” said Mbow.

Fire is used as a tool by local populations, for instance, when they’re gathering honey, clearing land or desiring new vegetation growth. Mbow says nearly all of the fires in the savannahs are caused by humans. Nature plays a very small role.

“The conditions in which natural fire can occur [are] when lightning happens, for instance. In Africa, when lightning happens in these tropical areas that’s a period during which we have rain. It’s wet. When it’s raining, that’s the time we have lightning, and it’s very unlikely that when it’s raining fire can take place,” he said.

With climate change, he said, there’s concern the savannahs will become even more dry, making destructive wildfires much more likely.

That’s why scientists at the World Agroforestry Center and their partners developed a system to pinpoint the best times to intentionally set fires. It’s known as early burning. It consumes layers of biomass before they build-up to highly combustible levels. Efforts to prevent fires altogether can actually make things worse.

“If you protect this area for five years, let’s say, or 10 years, you’ll have a dangerous amount of biomass. Fire not only consumes the biomass, it also destroys all the characteristics of the ecosystem, which makes this ecosystem viable. I’m thinking about microorganisms in the soil, small animals. So it’s a bit dangerous to over protect the ecosystem,” he said.

So an early burn, Mbow said, needs to be done when the conditions are just right – not too wet or not too dry. Fires intentionally set at that time not only consume the biomass, but prevent dangerous fires later in the season.

“There are many factors in determining fires. The one factor is the grass moisture, but also the grass load. The biomass load is extremely important. The second important factor is the atmospheric parameters – air temperature and wind. And the third one is the topography. If you are in heavy conditions, it’s very risky sometimes to use fire. As they go uphill they become stronger and very difficult to control. So there are many, many aspects which should be in consideration. And there is no silver bullet or one-size-fits-all situation.”

The early burns are generally fast moving and stay mainly on the surface. They cause only minor damage to trees, soil nutrients or microorganisms.

The recommendations for controlled fires in African grasslands can be found in the February issue of the Journal for Arid Environments. Mbow said that he hopes African governments will consider implementing them. However, he added, few countries on the continent currently have resources for fire management.

You May Like

Video Americans, Tourists, Reflect on Meaning of Thanksgiving

VOA garnered opinions from several people soon after November 13 Paris attacks, which colored many of their thoughts

Video Thais Send Security Concerns Down the River

In northern Thailand, the annual tradition of constructing floating baskets to carry away the year’s bad spirits highlights the Loy Krathong festival

Video Tree Houses - A Branch of American Dream

Workshops aimed at teaching people how to build tree houses have become widely popular in America in recent years

By the Numbers

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Belgium-Germany Border Remains Porous, Even As Manhunt For Paris Attacker Continuesi
Ayesha Tanzeem
November 25, 2015 10:46 PM
One of the suspected gunmen in the Nov. 13 Paris attacks, Salah Abdeslam, evaded law enforcement, made his way to Belgium, and is now believed to have fled to Germany. VOA correspondent Ayesha Tanzeem makes the journey across the border from Belgium into Germany to see how porous the borders really are.

Video Belgium-Germany Border Remains Porous, Even As Manhunt For Paris Attacker Continues

One of the suspected gunmen in the Nov. 13 Paris attacks, Salah Abdeslam, evaded law enforcement, made his way to Belgium, and is now believed to have fled to Germany. VOA correspondent Ayesha Tanzeem makes the journey across the border from Belgium into Germany to see how porous the borders really are.

Video Islamic State Unfazed by Losses in Iraq, Syria

Progress in the U.S.-led effort to beat Islamic State on its home turf in Iraq and Syria has led some to speculate the terror group may be growing desperate. But counterterror officials say that is not the case, and warn the recent spate of terror attacks is merely part of the group’s evolution. VOA National Security correspondent Jeff Seldin has more.

Video Taiwan Looks for Role in South China Sea Dispute

The Taiwanese government is one of several that claims territory in the hotly contested South China Sea, but Taipei has long been sidelined in the dispute, overshadowed by China. Now, as the Philippines challenges Beijing’s claims in an international court at The Hague, Taipei is looking to publicly assert its claims. VOA’s Bill Ide has more from Beijing.

Video Syrian Refugees in US Express Concern for Those Left Behind

Syrian immigrants in the United States are concerned about the negative tide of public opinion and the politicians who want to block a U.S. plan to accept 10,000 Syrian refugees. Zlatica Hoke reports many Americans are fighting to dispel suspicions linking refugees to terrorists.

Video After Paris Attacks, France Steps Up Fight Against IS

The November 13 Paris attacks have drawn increased attention to Syria, where many of the suspected perpetrators are said to have received training. French President Francois Hollande is working to build a broad international coalition to defeat Islamic State in Syria and in Iraq. Zlatica Hoke reports.

Video US, Cambodian Navies Pair Up in Gulf of Thailand

The U.S. Navy has deployed one of its newest and most advanced ships to Cambodia to conduct joint training drills in the Gulf of Thailand. Riding hull-to-hull with Cambodian ships, the seamen of the USS Fort Worth are executing joint-training drills that will help build relations in Southeast Asia. David Boyle reports for VOA from Preah Sihanouk province.

Video Americans Sharpen Focus on Terrorism

Washington will be quieter than usual this week due to the Thanksgiving holiday, even as Americans across the nation register heightened concerns over possible terrorist threats. VOA’s Michael Bowman reports new polling data from ABC News and the Washington Post newspaper show an electorate increasingly focused on security issues after the deadly Islamic State attacks in Paris.

Video World Leaders Head to Paris for Climate Deal

Heads of state from nearly 80 countries are heading to Paris (November 30-December 11) to craft a global climate change agreement. The new accord will replace the Kyoto Protocol on Climate Change that expired in 2012.

Video Uncertain Future for Syrian Refugee Resettlement in Illinois

For the trickle of Syrian refugees finding new homes in the Midwest city of Chicago, the call to end resettlement in many U.S. states is adding another dimension to their long journey fleeing war. Organizations working to help them integrate say the backlash since the Paris attacks is both harming and helping their efforts to provide refugees sanctuary. VOA's Kane Farabaugh reports.

Video Creating Physical Virtual Reality With Tiny Drones

As many computer gamers know, virtual reality is a three-dimensional picture, projected inside special googles. It can fool your brain into thinking the computer world is the real world. But If you try to touch it, it’s not there. Now Canadian researchers say it may be possible to create a physical virtual reality using tiny drones. VOA’s George Putic reports.

Video New American Indian Village Takes Visitors Back in Time

There is precious little opportunity to experience what life was like in the United States before its colonization by European settlers. Now, an American Indian village built in a park outside Washington is taking visitors back in time to experience the way of life of America's indigenous people. Carol Pearson narrates this report from VOA's June Soh.

Video Even With Hometown Liberated, Yazidi Refugees Fear Return

While the northern Iraqi town of Sinjar has been liberated from Islamic State forces, it's not clear whether Yazidi residents who fled the militants will now return home. VOA’s Mahmut Bozarslan talked with Yazidis, a religious and ethnic minority, at a Turkish refugee camp in Diyarbakır. Robert Raffaele narrates his report.

Video Nairobi Tailors Make Pope Francis’ Vestments

To ensure the pope is properly attired during his visit, the Kenya Conference of Catholic Bishops asked the Dolly Craft Sewing Project in the Nairobi slum of Kangemi to make the pope's vestments, the garments he will wear during the various ceremonies. Jill Craig reports.

Video Cross-Border Terrorism Puts Europe’s Passport-Free Travel in Doubt

The fallout from the Islamic State terror attacks in Paris has put the future of Europe’s passport-free travel area, known as the "Schengen Zone," in doubt. Several of the perpetrators were known to intelligence agencies, but were not intercepted. Henry Ridgwell reports from London European ministers are to hold an emergency meeting Friday in Brussels to look at ways of improving security.

Video El Niño Brings Unexpected Fish From Mexico to California

Fish in an unexpected spectrum of sizes, shapes and colors are moving north, through El Niño's warm currents from Mexican waters to the Pacific Ocean off California’s coast. El Nino is the periodic warming of the eastern and central Pacific Ocean. As Faiza Elmasry tells us, this phenomenon thrills scientists and gives anglers the chance of a once-in-a-lifetime big catch. Faith Lapidus narrates.

Video Terrorism in Many Forms Continues to Plague Africa

While the world's attention is on Paris in the wake of Friday night's deadly attacks, terrorism from various sides remains a looming threat in many African countries. Nigerian cities have been targeted this week by attacks many believe were staged by the violent Islamist group Boko Haram. In addition, residents in many regions are forced to flee their homes as they are terrorized by armed militias. Zlatica Hoke reports.

Video Study: Underage Marriage Rate Higher for Females in Pakistan

While attitudes about the societal role of females in Pakistan are evolving, research by child advocacy group Plan International suggests that underage marriage of girls remains a particularly big issue in the country. VOA’s Ayesha Tanzeem reports how such marriages leads to further social problems.

VOA Blogs