In a world where the climate crisis looms large, Professor Ken Byrne’s research group at the University of Limerick (UL) are investigating key questions concerning the contribution of land use and soils to Climate Action. Ken contextualises this work as follows: “Sustainable land use is critical to Climate Action and Life on Land. My research group studies greenhouse gas balances and carbon sequestration in forest and peatland ecosystems. This contributes to understanding the role of land use in greenhouse gas emissions and in the development of climate goals. A key future challenge for land use is to balance the multiple social, economic, and environmental roles of the sector while achieving climate neutrality”. Despite decades of climate change research, our knowledge is incomplete with many unanswered questions, for example, how different types of land use impact carbon emissions and carbon uptake.

To advance our understanding of the role of carbon sequestration in the fight against climate change, we asked Ken some salient questions about the work of his research group.

What role do trees play?  

Trees, and forest ecosystems, play a key role as they live for a long time and can store, or sequester, carbon in biomass and soil. Therefore trees, and forest ecosystems, act as carbon stores and can help to mitigate or offset greenhouse gas emissions. In addition, when forests are managed sustainably, biomass and timber harvested from them can be used to replace fossil energy or energy intensive building materials. However, because forest ecosystems store vast amounts of carbon, deforestation release substantial amounts of carbon into the atmosphere.  

What is forest carbon balance and or carbon sequestration?  

The carbon balance in a forest ecosystem is the difference between carbon uptake (photosynthesis) and loss (e.g., respiration, organic matter decomposition, fire, timber harvesting). When uptake exceeds loss the carbon balance is positive, and the ecosystem is a carbon sink. On the contrary, when loss exceeds uptake the carbon balance is negative, and the ecosystem is a carbon source. A carbon source contributes to greenhouse gas emission and a carbon sink mitigates or reduces them.  

Are certain native species more effective at carbon balance? 

At present we have little information on carbon uptake in native woodland. Carbon uptake is linked to the rate of forest growth and exotic coniferous species grow quickly. Therefore, they have a high rate of carbon uptake. When considering the role of forest ecosystems in climate change mitigation we need to consider not just whether they are native, exotic, broadleaved or coniferous but also all aspects of the forest production cycle, from initial planning, through the management cycle, to harvesting and the end use of the timber.  

What types of smart technologies are you using to do your field work? 

For the purposes of this research project, we are using drones, sensors, aerial photography, and satellite imagery as well as traditional field techniques to investigate the carbon balance in a range of forest ecosystems.  

What type of impact do you think your work will have?  

Our work will improve our understanding of the carbon balance in Irish forests. It will enable the development of new methods to assess the carbon balance of all our forests across time and space. This will improve the national greenhouse gas inventory and inform national policy on climate action and land use.  

What types of trees should we be planting in our own gardens? 

As the saying goes ‘the best time to plant a tree was 20 years ago. The second-best time to plant a tree is now.’ I would encourage people to plant trees in their gardens. Plant a tree which is pleasing to look at (colour of foliage, bark, or flowers in spring) that will grow happily in your garden. It can also provide habitat. A garden centre or nursery should be able to advise. 

Ken and team have two key projects: 

  1. Terrain-AI which aims at improving our understanding of the impact of human activity on land use as a driver of climate change and is in the process of establishing benchmark sites at forest, cropland, grassland, peatland, and urban locations. The established sites — including the forest sites UL is jointly responsible for — are already collecting vast quantities of data using field-level sensors, drones, aircraft, and satellites. A data platform is collating all the datasets related to greenhouse gas (GHG) emissions and land use to enable further modelling and analysis.   
     
  2. AdaptForRes which aims to develop strategies — adapt, mitigate, and protect — to increase resilience of Irish forests so they can be effective natural climate solutions. UL will study the forest carbon balance to assess how the carbon sequestration by the forestry sector can be maximised and GHG emissions curbed. UL, through their contributions to Terrain-AI and AdaptForRes, are helping to find answers to pressing questions on climate change.

To find out more about Ken's work, you can contact ken.byrne@ul.ie