Deforestation is seen as one of the biggest contributors towards overall forest carbon emissions, however the contribution of forest degradation has been largely unknown. Recent work has shed more light on this issue.
According to a recent study by Winrock International published in Carbon Balance and Management, a significant amount of carbon dioxide emissions are caused by rainforest degradation rather than deforestation. The authors argue that rainforest degradation has not been understood and studied properly as many international reduction programs have focused more on, the easier to detect, deforestation.
The work undertaken demonstrates that emissions from degradation has been a much higher proportion from expected. From the countries studied, a third of the forest degradation emissions were higher than the emissions of deforestation, and that degradation of forests comprise a quarter of combined emissions between forest degradation and deforestation. The researchers estimated the annual emissions of degradation is 2.1 billions tons of carbon dioxide, around half of that being timber harvest, 30% from wood fuel harvesting, and the remaining 17% coming from forest fires.
It was also found that degradation emissions seem to differ according to region, as the countries with the highest carbon emissions from forest degradation (Indonesia, Brazil, India, Malaysia, and the Philippines) all have different drivers. Where wood fuelling harvest dominates in Southern Asia (India) and East Africa (Kenya), selective logging for timber is the leader of emissions in South America (Brazil, Mexico) and Southeast Asia (Indonesia).
So what can we do?
Here at Carbomap we use LiDAR to help map both deforestation and degradation, however the approach we take for each is different. When mapping deforestation lower resolution data can be used as the difference between intact forest and deforestation is stark. Radar in particular is great for mapping deforestation, as the satellite data gives a low-cost synoptic view of large areas which making it very effective.
Mapping Degradation on the other hand is a more difficult task, as the indicators of degradation are often underneath the canopy. This is where Full-Waveform Lidar really comes into its own. Carbomap specialise in the processing of full-waveform Lidar to extract important metrics from the structurally complex undercanopy. This allows us to identify changes to the forest, due to degradation activities, that may not be possible to detect with satellite or discrete return Lidar.
Why is this important?
In addition to being a large source of carbon sequestration, forests provide other vital services including livelihoods, water, and habitats for millions of humans as well as flora and fauna. They are essential for combating climate change and are the focus of UN-backed international initiatives to provide evidence-based remuneration for forest protection such as REDD+. Reducing Emissions from Deforestation and forest Degradation (REDD+) is a mechanism with the aim of mitigating climate change by decreasing carbon emissions, whilst protecting forests and the ecosystem services they provide. REDD+ his a vehicle to financially reward developing countries for reducing emission through the conservation, sustainable management, and enhancement of forests.
So why is this relevant? The clue is in the name, deforestation and degradation. The ability to accurately monitor deforestation and forest degradation is vital for underpinning to basis on which schemes like REDD+ operate.