Every year, deliberately set fires and wildfires burn millions of hectares of forests and other types of vegetation around the world. In 2015, approximately 98 million hectares of forest were affected by fires (FAO, 2020). These fires occurred mainly in the tropics, where they damaged about 4 percent of the forest area.

The immediate and long-term impacts of wildfires can be devastating to communities, economies and forest ecosystems. The increase in forest wildfires around the world also threatens the long-term permanence of carbon stocks in all types of forests, forest regeneration and restoration projects. Many countries in Asia-Pacific are vulnerable to this threat, including Timor-Leste. In order to protect its forests, the government is rethinking its fire management and monitoring techniques. Recognising remote sensing as a vital tool for burned area mapping, Timor-Leste is working on generating historical background and fire frequency maps. These critical steps will allow the country to review and analyse fire sources, agencies and motivations - all crucial for identifying risk reduction activities. 

Forest fires and Timor-Leste

Timor-Leste is considered to be one of the countries most at risk of experiencing a natural disaster. Around 80% of Timorese have experienced the effects of natural disasters, including wildfires, in their lifetime. The vulnerability of Timor-Leste is high due to a significant lack of institutional and community coping and adapting capacities. In addition, the country previously had no opportunity to assess the extent and origins of wildfires, both essential for any fire prevention strategies.

Despite the impact of fire on forest and land degradation, biodiversity, and agriculture productivity, there has been little discussion and awareness-raising activities of these challenges in Timor-Leste. As a result, the traditional swidden agriculture practices using fire, otherwise referred to as slash-and-burn, continue to persist.

Recognising the need to understand and quantify the key drivers and types of wildfires in Timor-Leste, the country is collaborating with the Food and Agriculture Organization of the United Nations (FAO) to improve its fire monitoring knowledge and capacities. With the support of FAO forest monitoring tools like SEPAL, the country is in the process of measuring the extent of damage from wildfires over the past 30 years. The gathered data will help the country identify the extent of forest fires and the location of wildfire hotspots. 

"It was assumed that unsustainable agricultural practices, including slash-and-burn and the crop residue burning, are among the main drivers of forest fires in Timor-Leste,” says Julian Fox, FAO NFM Team Leader. "Now, with SEPAL, we can finally have data going 30 years back to test this assumption and take data-driven actions to prevent possible future wildfires." 

The map based on Timor-Leste's fire study analysis showing the annual burned area over five years (2001-2005). ©FAO

The work would not be possible without SEPAL, FAO’s cloud computing platform comprised of a set of innovative open-source tools that provide comprehensive image processing capabilities and enables the detection of small-scale changes in forests, such as shifting cultivation activities. Harnessing cloud-based supercomputers and modern geospatial data infrastructure (such as Google Earth Engine), SEPAL allows for fast and easy processing of critical satellite data. In Timor-Leste, the team is working with Landsat 30-meter resolution imagery from the period of 1991-2020. Landsat data is freely available and contains historical images starting from 1983, which greatly facilitates the analysis of trends of fires and their impact on forests. Field, verification will be organized at the later stage of the project during fire season to calibrate the remote seeing work.  The data will be critical to gather information on the country’s shifting slash and burn agriculture. 

Tracking slash-and-burn shifting cultivation in Timor-Leste

One of the common agricultural practices in Timor-Leste is slash-and-burn shifting cultivation. The method involves cutting and burning vegetation or forest during the dry season, mostly in October and November. Newly opened land is cultivated for 1 to 7 years, depending on the initial soil fertility and slope, before it is left fallow.

According to FAO estimates, slash-and-burn agriculture has the highest productivity of any non-mechanized agriculture system, allowing farmers to obtain 40 kg of corn per labour day spent in their field. Considering a farm gate price of $0.35/kg, this represents $14 per labour day.

‘’Millennial ‘slash-and-burn’ agriculture is an efficient land management technique that the population of Timor-Leste has successfully used to ensure their food supply through the centuries,” says Raphy Favre, FAO’s fire study Team Leader. “However, with increasing population pressure, the practice is now being recognized as the top contributor to deforestation, land and environmental degradation, loss of biodiversity and water regime degradation. The practice is therefore stripping vital resources for future generations’ livelihoods’’.

At the moment, no official data on slash-and-burn shifting cultivation in Timor-Leste exists. However, studies suggest that 87% of farmers in Timor-Leste are using this practice. Given the pronounced dry season, running between June to October/November, the practice becomes a major source of wildfires in the country.

Remote sensing data can, in the future, further support assessment of the available fuel load for fires as well as the production of a vulnerability map. The collected remote sensing information can provide an important part of the basis for integrated fire management activities involving various government agencies and different administrative levels, including, importantly, local communities. In addition, as part of the project, focus group discussions with local communities were organised to better understand the nature of the fires and examine how the communities manage them. 

Left: Slash-and-burn field recently opened for cultivation. Alieu, October 2018. Right: same land abandoned the following year. June 2020

The impact of forest fires on climate change

In some ecosystems, natural fires are essential to maintain ecosystem dynamics, biodiversity and productivity. Fire is also an important and widely used tool to meet land-management goals. Most fires are caused by people, and sometimes they get out of control. 

“FAO considers that understanding fire in forest loss is important in identifying ways to reduce the risk of emissions from land use change and damaging wildfires. Recent analysis for forest loss and fires suggests that on average, about one third of forest loss was associated with fire” say Peter Moore, FAO Forestry Officer. “Therefore, being able to assess these changes using tools such as remote sensing is an important step in working with countries to distinguish between fires that are changing landscapes and forests, and those that are not, to inform addressing the risks.”

In the context of REDD+, forest fires can play a crucial role at the country level, and in one way or another they can affect (mostly negatively) all five of REDD+ activities - reducing emissions from deforestation, reducing emissions from forested degradation, sustainable management of forests, conservation and enhancement of forest carbon stocks. Forest wildfires not only compromise carbon permanence in countries, but can also negatively impact human health, livelihoods and biodiversity, all three of which are REDD+ co-benefits. 

In Timor-Leste, initiatives to reduce forest fires are an important part of the country's efforts to halt deforestation, as the efforts on fires become valid forest conservation activities and central environmental safeguards that have a potential to cut across all three phases of REDD+ activities (readiness, implementation and results assessment). 

In the future, climate change is expected to cause longer fire seasons and more-severe fires over much of the globe, including some areas where fire has not previously been a common problem. Oftentimes, damaging forest fires cannot be avoided but their occurrence and impacts can be significantly reduced. This can only be achieved by applying data-driven, integrated fire and fire-smart forest management and by taking sociocultural realities and ecological imperatives into account - for the benefit of the people, forests and climate.

Click for more