Featured Research

from universities, journals, and other organizations

Scientists develop improved fire management tools for Africa's savannas

Date:
February 14, 2013
Source:
World Agroforestry Centre
Summary:
Scientists have developed specialized graphs that map out fire behavior, known as nomographs, for landscape managers in Africa's savannas. The study pinpoints the optimal conditions for setting early-season prescribed fires -- a process that when executed and timed properly, reduces the risk and impact of late dry season bushfires in increasingly fragile ecosystems, both of which are exacerbated by climate change.

Scientists at the Nairobi-based World Agroforestry Centre (ICRAF) and partners have developed specialized graphs that map out fire behavior, known as nomographs, for landscape managers in Africa's savannas. The study, published in the February issue of the Journal of Arid Environments, pinpoints the optimal conditions for setting early-season prescribed fires -- a process that when executed and timed properly, reduces the risk and impact of late dry season bushfires in increasingly fragile ecosystems, both of which are exacerbated by climate change.

Researchers say the findings signify an important step for Africa's Sudanian and Sahelian savannas, which have historically relied on less accurate methods to time early-dry-season controlled fires. The study finds it is necessary to use tools that consider both fuel characteristics and weather conditions, when planning these prescribed fires.

Fire has been battled by land managers for decades, but that doesn't make it a foe. In seasonally-dry savanna ecosystems -- which dominate nearly half of Africa's surface area -- naturally-occurring wildfires are critical to maintaining biodiversity and ecosystem function.

"The key to fighting fire with fire is robust science," said Cheikh Mbow, senior climate change scientist with the World Agroforestry Centre. "In the past, forest managers did not have the tools and methods needed to define what to burn, when to burn it, and to what extent. Our research is helping transform an age-old practice into a modern-day tool for managing fires and ecosystems in West Africa. This is a simple statistical tool that can be replicated most anywhere."

The scientists selected three areas representative of Senegalese savanna ecosystems, ranging from the open savanna of the Sahel to the more treed south-Sudanian savanna. They worked with Senegal's Forestry Service to torch 231 prescribed 10-by-10 meter plots (an area roughly the size of three football pitches) in Senegal at the end of the 2010 rainy season. They recorded data on air temperature, relative humidity, wind speeds, fuel load and cover, fuel moisture content and the amount of dry matter present.

Researchers found that the best time to ignite preemptive fires was when fuel moisture content -- the amount of water a fuel holds, expressed as a percentage of its dry weight -- was close to 120 percent and relative air humidity was between 12 and 79 percent. This was equivalent to between 12 days and one month after the last rain, depending on the site. They also found that the fires' rate of spread was greater when wind speeds were fast and fuel moisture content, relative humidity and fuel load were all low.

Their results showed that a fuel load of 94 grams per square meter is sufficient to support savanna fires in West Africa -- less than half of what's required for savanna fires to propagate in South Africa. This is likely due to high grass cover and fast wind speeds.

"Fires have long been regarded as the enemies of the savanna, but since time immemorial, they have played a role in keeping these ecosystems functioning optimally, keeping the domination of some species over others in check," said Momadou Sow of the Environmental Sciences Institute of the Cheikh Anta Diop University in Dakar, Senegal. "Until now, we've lacked the accurate scientific knowledge to properly plan early season prescribed fires in West African savannas -- our research is a step towards filling that gap."

Wildfires, like the hundreds that ravaged southeast Australia and Tasmania in early January, can cause widespread environmental devastation and destruction of property. Once the infernos gather strength, aided by wind and ample fuel supplies, they become uncontrollable and can travel large distances, destroying infrastructure, wreaking havoc on ecosystems, releasing millions of tonnes of greenhouse gases into the atmosphere and costing billions of dollars in damage.

Wildfires also threaten biodiversity, including many unique plants and animals found only on the continent. Many animals that dwell in trees, bushes, deadfall or underground perish from the blazes or succumb later from lack of food and shelter or increased predation. In Australia for instance, the koala is especially vulnerable to wildfires that consume the tree canopy, as the animals are slow-moving and do not use hollows, in which they could shelter.

"In Senegal, the lack of equipment and qualified human resources for firefighting make late-season fires an especially large threat. But the outcomes of this study -- especially the ability to reliably predict fire rate of spread and fuel consumption -- should allow better planning of fires based on desired characteristics in the future," said Mbow.

Fast-moving savanna fires generally remain on the surface, inflicting only minimal damage on trees, barely heating the soil below and leaving roots, nutrients and microorganisms unharmed. These frequent, low-intensity fires are what forest managers attempt to mimic in order to limit dangerous fuel build-up.


Story Source:

The above story is based on materials provided by World Agroforestry Centre. Note: Materials may be edited for content and length.


Cite This Page:

World Agroforestry Centre. "Scientists develop improved fire management tools for Africa's savannas." ScienceDaily. ScienceDaily, 14 February 2013. <www.sciencedaily.com/releases/2013/02/130214194109.htm>.
World Agroforestry Centre. (2013, February 14). Scientists develop improved fire management tools for Africa's savannas. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2013/02/130214194109.htm
World Agroforestry Centre. "Scientists develop improved fire management tools for Africa's savannas." ScienceDaily. www.sciencedaily.com/releases/2013/02/130214194109.htm (accessed July 24, 2014).

Share This




More Earth & Climate News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Observation Boat to Protect Cetaceans During Ship Transfer

Observation Boat to Protect Cetaceans During Ship Transfer

AFP (July 22, 2014) As part of the 14-ship convoy that will accompany the Costa Concordia from the port of Giglio to the port of Genoa, there will be a boat carrying experts to look out for dolphins and whales from crossing the path of the Concordia. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
New Orleans Plans to Recycle Cigarette Butts

New Orleans Plans to Recycle Cigarette Butts

AP (July 21, 2014) New Orleans is the first U.S. city to participate in a large-scale recycling effort for cigarette butts. The city is rolling out dozens of containers for smokers to use when they discard their butts. (July 21) Video provided by AP
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
Spectacular Lightning Storm Hits London

Spectacular Lightning Storm Hits London

AFP (July 19, 2014) A spectaCular lightning storm struck the UK overnight Friday. Images of lightning strikes over the Shard and Tower Bridge in central London. Duration: 00:23 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins